Robot surgery

Robot Surgery

Robot Surgery

Edited by

Seung Hyuk Baik

Intech

IV

Published by Intech

Intech Olajnica 19/2, 32000 Vukovar, Croatia Abstracting and non-profit use of the material is permitted with credit to the source. Statements and opinions expressed in the chapters are these of the individual contributors and not necessarily those of the editors or publisher. No responsibility is accepted for the accuracy of information contained in the published articles. Publisher assumes no responsibility liability for any damage or injury to persons or property arising out of the use of any materials, instructions, methods or ideas contained inside. After this work has been published by the Intech, authors have the right to republish it, in whole or part, in any publication of which they are an author or editor, and the make other personal use of the work. © 2010 Intech Free online edition of this book you can find under www.sciyo.com Additional copies can be obtained from: [email protected] First published January 2010 Printed in India Technical Editor: Teodora Smiljanic Robot Surgery, Edited by Seung Hyuk Baik p. cm. ISBN 978-953-7619-77-0

Preface Robotic surgery is yet in the early stages even though robotic assisted surgery is increasing continuously. Thus, exact and careful understanding of robotic surgery is necessary because chaos and confusion exist in the early phase of anything. Especially, the confusion may be increased because the robotic equipment, which is used in surgery, is different from the robotic equipment which is used in the automobile factory. The robots in the automobile factory just follow a program. However, the robot in surgery has to follow the surgeon’s hand motions. I am convinced that this In-Tech Robotic Surgery book will play an essential role in giving some solutions to the chaos and confusion of robotic surgery. The In-Tech Surgery book contains 11 chapters and consists of two main sections. The first section explains general concepts and technological aspects of robotic surgery. The second section explains the details of surgery using a robot for each organ system. I hope that all surgeons who are interested in robotic surgery will find the proper knowledge in this book. Moreover, I hope the book will perform as a basic role to create future prospectives. Unfortunately, this book could not cover all areas of robotic assisted surgery such as robotic assisted gastrectomy and pancreaticoduodenectomy. I expect that future editions will cover many more areas of robotic assisted surgery and it can be facilitated by dedicated readers. Finally, I appreciate all the authors who sacrificed their time and effort to write the book. I must thank my wife NaYoung for her support and also acknowledge MiSun Park’s efforts in helping complete the book.

Editor

Seung Hyuk Baik, MD, PhD Yonsei University, Seoul, Korea

Contents Preface

V

SECTION I

1. Classification, Design and Evaluation of Endoscope Robots

001

Kazuhiro Taniguchi, Atsushi Nishikawa, Mitsugu Sekimoto, Takeharu Kobayashi, Kouhei Kazuhara, Takaharu Ichihara, Naoto Kurashita, Shuji Takiguchi, Yuichiro Doki, Masaki Mori, and Fumio Miyazaki

2. Extreme Telesurgery

025

Tamás Haidegger and Zoltán Benyó

3. Telementoring and Telesurgery: Future or Fiction?

045

Vitor da Silva, Tom McGregor, Reiza Rayman, Patrick PW Luke

4. Simulation Model for the Dynamics Analysis of a Surgical Assistance Robot

057

Hans-Christian Schneider and Juergen Wahrburg

SECTION II

5. Robotic Assisted Colorectal Surgery

073

Seung Hyuk Baik, M.D.

6. Robotic Surgery of the Colon: The Peoria Experience

095

Steven S Tsoraides, M.D., M.P.H., Franziska Huettner, M.D., P.h.D., Arthur L Rawlings M.D., M.Div. and David L Crawford, M.D.

7. Robotic Sacrocolpopexy and Sacrocervicopexy for the Correction of Pelvic Organ Prolapse

109

James C Brien, Michael D Fabrizio and James C Lukban

8. Robotic Assisted Laparoscopic Hysterectomy Khaled Sakhel

123

VIII

9. Robotic Surgery for Lung Cancer

135

Joao-Carlos Das-Neves-Pereira, Marc Riquet, Françoise Le-Pimpec-Barthes, Paulo-Manuel Pego-Fernandes and Fabio Biscegli Jatene

10. Robotic Surgery in Ophthalmology

149

Irena Tsui, Angelo Tsirbas, Charles W. Mango, Steven D. Schwartz and Jean-Pierre Hubschman

11. Robot-assisted Laparoscopic Central Pancreatectomy with Pancreaticogastrostomy (Transgastric Approach) Chang Moo Kang, M.D.

165

SECTION I

1 Classification, Design and Evaluation of Endoscope Robots Kazuhiro Taniguchi1, Atsushi Nishikawa2, Mitsugu Sekimoto3, Takeharu Kobayashi4, Kouhei Kazuhara4, Takaharu Ichihara4, Naoto Kurashita4, Shuji Takiguchi3, Yuichiro Doki3, Masaki Mori3, and Fumio Miyazaki2 1Graduate

School of Engineering, The University of Tokyo, School of Engineering Science, Osaka University, 3Graduate School of Medicine, Osaka University, 4Research & Development Center, Daiken Medical Co., Ltd. Japan

2Graduate

1. Introduction With development of endoscopic surgery and medical robotics, surgery using endoscope robots has become a representative of robotic surgery. This chapter describes classification, design methods and evaluation methods of endoscope robots. Expectations for a minimally invasive surgery have increased year by year with the dramatic advancement of image diagnosis technology, including CT and MRI. A camera (endoscope) and surgical instruments are inserted into tiny holes made in the patients’ abdomen or chest region for surgical procedures. Compared to abdominal or open chest surgery, endoscopic surgery has less pain and has a greater advantage in cosmetic appearance as well as the economic advantages, resulting in its growing popularity. The most distinctive feature of endoscopic surgery is that the surgical field is observed through images taken by an endoscope, rather than the naked eye. The most important element to surgical safety and efficient operating is how well an endoscope reveals the field of view during surgery. Generally, a camera assistant operates the endoscope. The operation of the endoscope needs fine adjustment for the angle of the field of view and the distance of the surgical area as well as correct aiming of the endoscope at the surgical field. Camera assistants sometimes operate the endoscope according to instructions of a surgeon; however, camera assistants need to operate the endoscope using their judgment in understanding the surgeon’s intentions so that they can move the endoscope according to how the surgery is progressing moment to moment. The operation of an endoscope by camera assistants requires as much proficiency as that of surgeons. There are not many surgeons who have sufficient proficiency in endoscopic surgery, which requires special techniques. In fact, it is not unusual for surgery to be interrupted due to a camera assistant not being sufficiently proficient in using the endoscope and is unable to obtain the exact field of surgery required. To solve this problem, "endoscope robots that can hold and position an endoscope instead of a human camera assistant" (Fig. 1) have been developed. Fig. 1(a) shows a usual endoscopic

2

Robot Surgery

surgery where a human camera assistant operates an endoscope and Fig. 1(b) shows an endoscopic surgery using an endoscope robot. Among endoscope robots reported so far, NaviotTM (Kobayashi et al., 1999, Tanoue et al., 2006) made by Hitachi in Japan, AESOPTM (Sackier & Wang, 1994) made by Computer Motion (Intuitive Surgical) in the U.S.A and EndoAssistTM (Finlay, 2001) made by Prosurgics in England have been commercialized and widely used. The commercialized endoscope robots operate according to surgeon’s instructions with switches by hand or voice recognition technology. There are some robots, still being studied, which automatically position the endoscope while the robot itself interprets the surgeon movements. The endoscope positioning system (Nishikawa et al., 2006, Nishikawa et al., 2008)developed by Nishikawa et al. represents an automatic endoscope positioning robot.

(a)

(b)

Fig. 1. Endoscopic surgery (a) A human camera assistant operates the endoscope. (b) An endoscope robot operates the endoscope.

Fig. 2. Endoscope robot as an interactive media

Classification, Design and Evaluation of Endoscope Robots

3

As shown in Fig. 2, we have developed endoscope robots by separating them into two systems: System A, which receives information (intention) from surgeons, and System B, which positions the endoscope and provides information, to the surgeons, including images taken by the endoscope. System A is the human interface and controller and System B is the manipulator, endoscope equipment and navigation equipment. Upon developing endoscope robots, we develop System A and System B separately and evaluate and review them separately. Then, System A and System B are integrated and evaluated comprehensively. When System A and System B are evaluated separately, a manipulator system where System B is simulated is used for System A and a human interface where System A is simulated is used for System B. More specifically, a robot with only necessary degrees of freedom is realized and commercially available endoscope equipment are used for System A and joystick interface is used for System B in most evaluations. In Fig. 2, a loop (LoopSAB) of "surgeon → System A → System B → surgeon" interaction is built between an endoscope robot and the surgeon. That is, an endoscope robot is treated as a part of the interactive media. In the endoscope robot, a surgeon works on System A (intention), System A receives the intention from the surgeon and outputs a control signal (intention) to System B. As a result, System B is properly controlled and sends new information to the surgeon. Hence, surgeons can "expand their human abilities" through this interactive media. "Intention" means information to make an effect on items sent and received. We call mutual information flow between humans and the system which is performed to expand human abilities as an interaction loop. Proper information flow in the interaction loop establishes a strong link between humans and robots, resulting in cooperative work between humans and robots more efficient than that between humans and humans. There is a loop (LoopSPB) of "surgeon → patient → System B → surgeon" in Fig. 2. This loop is an interaction loop between surgeons and patients through systems (System B) such as manipulators. Analysis of this interaction loop enables evaluation of surgery or robots. This chapter focuses on LoopSAB for endoscope robot design methods and on LoopSPB for their evaluation methods.

2. Classification of endoscope robots Table 1 and Fig. 3 demonstrate classification results of the following 27 kinds of endoscope robots which are commercialized or published in article for referee reading as of September 2009: a) A460 CRS Plus (Hurteau et al., 1994), b)AESOPTM (Sackier & Wang, 1994), c)LARS(Taylor et al., 1995), d)EndoAssistTM (Endosista) (Finlay, 2001), e)Staubli Rx60(Munoz et al., 2000), f)ERM(Munoz et al., 2005), g)LapMan(Polet & Donnez, 2004), h)RES(Mizhuno, 1995), i)NaviotTM (Kobayashi et al., 1999, Tanoue et al., 2006), j)PASEO(Nishikawa et al., 2003), k)HISAR(Funda et al., 1995), l)ViKY(LER)(EndoControl, 2009, Long et al., 2007), m)5-DOFs Laparoscopic Assistant Robot(KaLAR) (Lee et al., 2003), n)FIPS(Buess et al.,2000), o)Imag Trac(Kimura et al., 2000), p)Wide-Angle View Endoscope(Kobayashi et al., 2004), q)Dual-View Endoscopic System(Yamauchi et al., 2002), r)Automatic Tracking And Zooming System(Nakaguchi et al., 2005), s)COVER(Taniguchi et al., 2006), t)P-arm(Sekimoto et al., 2009), u)Free hand(Prosurgics, 2009), v) Robolens (Sarkaret al., 2009), w)Swarup Robotic Arm (SWARM) (Deshpande, 2004), x)MST Laparoscope Manipulator(Szold et al., 2008, NGT, 2009), y)ROBOX(Rininsland, 1999, KIT, 2009, FZK, 2009), z) FELIX (Rininsland, 1999, FZK, 2009), aa) Paramis (Graur et al., 2009).

4

Robot Surgery

Endoscope robots are treated as interactive media described in the previous section and separated by LoopSAB and LoopSPB. For LoopSAB, a human machine interface was examined for System A and a manipulator was examined for System B. Table 1 demonstrates the results of the human machine interface and Fig. 3 indicates the manipulator.

a) A460CRS Plus b) AESOPTM c) LARS d) EndoAssistTM (Endosista) e) Staubli Rx60 f) ERM g) LapMan h) RES i) NaviotTM j) PASEO k) HISAR l) ViKY(LER) m)5-DOFs Laparoscopic Assistant Robot(KaLAR) n) FIPS endoarm o) I magTrac p) Wide-Angle View Endoscope q) Dual-View Endoscopic System r) Automatic Traking And Zooming System s) COVER t) P-arm u) FreeHand v) Robolens w) Swarup Robotic Arm (SWARM) x) MST Laparoscope Manipulator y) ROBOX z) FELIX aa) Paramis

Loop SAB System A Remote hand switch Voice recognition, remote hand switch, foot pedal Tool mounted switch

Loop SPB

Head control

Human

Voice recognition Voice recognition Tool mounted switch Head control, equipment tracking , hand and foot switches Tool mounted switch, head pose Face gesture Tool mounted switch voice recognition, foot control

Animal Human Product Product Animal Model Human

Voice, equipment tracking

Animal

Tool mounted switch, voice recognition Tool mounted switch, voice recognition

Model Human

Remote hand switch

Animal

Remote hand switch

Animal

Automatic tracking

Animal

Face gesture Joystick, automatic operation, touch screen, voice recognition Head pose Voice recognition

Animal Product Human

Remote controller

Human

Equipment tracking

Animal

Voice recognition, mouse, foot pedal, Equipment tracking Voice recognition Voice recognition

Human Product Animal

Model

Animal

Human Model Model

Table 1. Classification results of endoscope robots and human machine interface

Classification, Design and Evaluation of Endoscope Robots

5

Fig. 3. Classification results of characteristics of endoscope robots and manipulation: A)A460 CRS Plus, b)AESOP, c)LARS, d)EndoAssist(Endosista), e)Staubli Rx60, f)ERM, g)LapMan, h)RES, i)Naviot, j)PASEO, k)HISAR, l) ViKY(LER),m)5-DOFs Laparoscopic Assistant Robot(KaLAR), n)FIPS, o)Imag Trac, p)Wide-Angle View Endoscope , q)DualView Endoscopic System, r) Automatic Tracking And Zooming System, s)COVER, t)P-arm, u)FreeHand, v) Robolens, w)Swarup Robotic Arm (SWARM) , x)MST Laparoscope Manipulator, y)ROBOX, z) FELIX , aa) Paramis Among "safety", "compact and lightweight", "cleanliness" and "usability: popular general endoscopes can be used" which are required on the medical front, "safety" should be independently discussed as a necessary condition for a medical robot; therefore, System B of each endoscope robot is classified according to "compact and lightweight", "cleanliness" and "usability". The definition of "compact and lightweight" is that a manipulator is attached with a general-purpose endoscope holder or an endoscope and manipulator are combined. The definition of "cleanliness" is that the endoscope robot parts which are used in clean fields can be sterilized. Robots that maintain cleanliness using a sterilized drape is classified as unclean. The most popular general endoscopes are OLYMPUS and KARL STORZ, which are commercially available. Table 1 also shows the subject of endoscope robots of LoopSPB. We examined whether each endoscope robot has been commercialized, whether an endoscope robot is used in human surgery, whether an endoscope robot is used only on animals, whether an endoscope robot is used only in in-vitro experiment or whether an endoscope robot model has been completed and has not been evaluated. We described them as product, human being, animal and model respectively in the table. Fig. 3 shows that endoscope robots satisfying all items are l) ViKY(LER), t)P-arm ,and x)MST Laparoscope Manipulator only. Endoscope robots satisfying two out of three items of "compact and lightweight", "cleanliness" and "usability" are o)Imag Trac, p)Wide-Angle View Endoscope , q)Dual- View Endoscopic System, r) Automatic Tracking And Zooming System, s)COVER,

6

Robot Surgery

and u)FreeHand. A special endoscope for robots are used in o)Imag Trac, p)Wide-Angle View Endoscope, q)Dual-View Endoscopic System and high resolution CCD camera with a resolution of one million pixel (general pixel is four hundred thousand) is used in r) Automatic Tracking And Zooming System.

3. Design of endoscope robots and implementation examples This section describes specificity of endoscope robots and required items for endoscope robots based on specificity. Examples of endoscope robots developed based on the required items are desmonstrated. Design of endoscope robots is design of LoopSAB shown in Fig. 2. Information that surgeons output to System A feeds back to surgeons from System B in the form of image taken by the endoscope. A variety of useful systems have been developed for System A of an endoscope robot with remote control techniques, voice recognition, and image processing technology.In contrast, the development for System B has been slow due to the complication of the system with regard to specificity of purpose and the extensive contact it is required to have with patients on the medical front. This section explains System B, especially manupulator design. 3.1 Specificity of endoscope robots Industrial robots operate under environments where the robots are isolated from humans; however, endoscope robots support surgery coming in contact with patients while the robots and surgeons closely interact. Industrial robots perform work which has been planned in advance under a closed, unvaring environment; however, endoscope robots are used for surgery in the medical front with high entoropy, where mistakes or failures are unacceptable. In addition, even though the surgery methods may be the same, the surgery contents vary in each case since the patients having the surgery vary. Hence, required items for robots of industry and endoscope robots are entirely different. Robots for industry required "high power", "high speed" and "high accuracy". Endoscope robots requires "safety" and "cleaness" since the robots come into physically contact with humans. Upon designing robots, which work with humans, such as endoscope robots, "robot physical ability" and "robot computational ability" are points for designing the robots. It is necessary to design robots which have enough physical and computational abilities (artificial intelligence) to work with humans. To design a robot which does the housework including cleaning, washing or cooking, very high physical ability and computational ability are necessary for the robot. Physical and computational abilities of endoscope robots can be limited since the robots work with surgeons who have high intelligence for special tasks under special environments. A study group of Nishikawa et al. described before, have given much attention to interaction between humans and robots and realized the automatic operation of endoscope robots (Nishikawa et al., 2006, Nishikawa et al., 2008). For automation, Nishikawa analyzed the relatonship between endoscope images and surgical instruments in actual surgeries, and invented simple computation algorithms for endoscope robots specialized for specific tasks, without attempting to create endoscope robots that could understand the flow of the surgery, context of procedures or reasons behind actions. This algorithm has been designed focusing on the expansion of the ability of surgeons, and has obtained high reliability with introducing the concept of "fluctuation" as a characteristics of living bodies. This can be a good example of information in an interacton loop being

Classification, Design and Evaluation of Endoscope Robots

7

optimized between the surgeons and the endoscope robots. To design endoscope robots, it is important to consider the specificity of the endoscope robots and optimize LoopSAB interaction. 3.2 Required items for endoscope robots Necessary elements for the construction of endoscope robots are broken into "required items", "basic items" and "enhancement items". The required items are necessary conditions for the endoscope robots. The basic items are strongly influential in the basic concepts of endoscope robots, and enhancement items are items that provide additional functions to the endoscope robots. 3.2.1 Required items The required items are degree of freedom necessary for endoscope operations and safety as a medical equipment. It cannot be called an endoscope robot unless required items are met. First of all, we will describe degree of freedom. As shown in Fig. 4, since an endoscope operation during surgery is performed with insertion / retraction of an endoscope, roll around the insertion direction, and pitch and yaw based on the insertion site, the necessary degree of freedom for endoscope robots are four degrees of freedom. Roll is used to correct the top and bottom of image for direct-viewing endoscope and to observe the back of the organs for a oblique-viewing endoscope. Roll is not always necessary in surgery which targets narrow operation fields such as laparoscopic cholecystectomy. Among robots developed for the purpose of compact and to be lightweight, robots (Taniguchi et al., 2006) with three degrees of freedom with pitch, yaw and inserting, excluding roll, have been developed under conditions where the surgery target positions are limited. Degree of freedom as well as safety are the most important items for design of System B.

Fig. 4. Movement of endoscope: Since the endoscope is limited due to the insertion site, the endoscope has four degrees of freedom. Next, we will describe safety. Suggestions on the safe use of medical robots include suggestions by Leveson et al (Leveson & Turner, 1993) learn from "Therac-25 accidents" and suggestions (Taylor & Stoianovici, 2003) by Taylor et al. Referring to the suggestions, we have the following points for securing safety when using endoscope robots. • It is essential to secure mechanistic safety, and furthermore, the safety is secured by a control program (software) . • Several completely independent safety devices are used.

8 •

Robot Surgery

While endoscope robots are being developed, documents are created and managed, and examinations are steadfastly performed and discussed with the results being thoroughly managed. The quality of the products is fastidiously managed. • Several emergency cease functions are equipped. The emergency cease functions shall be installed at positions where the surgeons or nurses can immediately stop a endoscope robot. • Considering the environment where medical staff will use the robots, clinicians, medical staff, medical device manufacturers and engineers, in coordination, assess the risks. Opinions from the related meetings are emphasized. • The systems are designed so that surgeons can respond to stalled or runaway endoscope robots due to robot failure or dramatic environment changes, such as natural disasters, including earthquakes. Mechanisms to secure the above safety are equipped with System A and System B separately and each relationship shall be clarified. When study phases progress and practical use of endoscope robots is aimed at, it is necessary to comply with international standards including ISO and IEC on safety and JIS, Europe and U.S.A standards. The methods to secure safety of endoscope robots which are being studied and developed are described below. AESOP, which were commercialized in the 90’s and have been used worldwide, uses two control safety securing methods, "low limit setting" and "control disable function". The low limit setting is a function to secure safety, in which the lowest descendent position of a robot arm is set before surgery and the software controls the arm so it will not descend below the position crushing a patient’s body during surgery. The control disable function stops the arm movement when the patient moves, stress is applied to the arm movement, or the magnet for installing the endoscope is dislocated when something hits the tip of the endoscope or shear stress is applied to the endoscope installation portion of the arm. AESOP is safety managed by a control program and mechanical safety is not secured. In addition, safety mechanism of System A and System B is not independent and we judge that safety is not sufficiently secured. Next, we will describe how to secure safety for NaviotTM. As methods to secure mechanical safety, "optical zoom mechanism", "five joints link mechanism" and "limitation of degree of freedom" are introduced. In addition, the safety for System A and System B is completely independent. The optical zoom mechanism does not have a direct acting movement toward the interperitoneal direction by endoscopes and there is no possibility of interference with organs. The driving range of five link mechanisms is mechanically limited. Even when the endoscope robots malfunction or operate incorrectly, the robots do not move violently, the upper space of the abdominal cavity is secured and the surgery field is not interrupted. Limiting the degree of freedom and simplifying mechanisms cause less malfunction or incorrect movements. To secure control safety, a "status monitor function" is equipped. This function has function checkout functions before surgery and emergency cease functions when an overload (interference between patients or medical staff and robots) is observed during surgery. In addition, NaviotTM has a measure against electric insulation and an emergency cease switch. With all things considered, it is very safe. Many endoscope robots have been studied and developed, some of which do not secure sufficient safety; only mechanical safety is secured by processing values of a pressure sensor with software, or, only a degree of freedom around the insertion site is mechanically realized, resulting in insufficient safety.

Classification, Design and Evaluation of Endoscope Robots

9

3.2.2 Basic items The basic items include the dimension of the endoscope robot, methods to secure cleanliness, installation methods and the kinds of endoscopes used. Determining these items lead to determine concepts of endoscope robots, especially in System B. Changing the basic items often leads to changing the basic structure of System B of an endoscope robot. Changing the basic items makes an endoscope robot totally different. First of all, the dimension of endoscope robots is described. In Japan, development of compact and lightweight robots is popular. Compact and lightweight endoscope robots have advantages, such as they can be easily installed, cleanliness can be easily secured or it does not interrupt the surgery. Next, installation area of endoscope robots is described. There are four areas to be installed, the floor near a surgical table in the operating room, hanging from the ceiling near the surgical table, on the surgical table or on the abdomen of the patient. In many studies, the endoscope robot is installed on the floor of the operating room or on the surgical table. Efficiency when an endoscope robot is installed on the abdomen of the patient has been studied recently. It is better to discuss installation positions and installation methods of an endoscope manipulator while considering that a surgical table height or slant is sometimes adjusted during surgery. Then, a method to secure cleanliness is described. There are two kinds of methods to secure cleanliness of the endoscope robots, one of which is to cover the endoscope robot with a sterilized drape and the other is to sterilize only the mechanism used in the clean fields. A sterilized drape may tear during surgery due to the robot’s movement. Covering the robot with a sterilized drape would be a big burden to medical staff. Finally, the kinds of endoscopes used are described. Either commercially available endoscopes or endoscopes developed for a specified endoscope robot are used. We think the former is preferable. Compared to the ones developed for endoscope robots, it is better to use economic and high image quality endoscopes appropriate for the medical front which has been developed by endoscope manufacturers, and apply them to the endoscope robots. This has the advantage when the endoscopes are comprehensively evaluated from a point of view of cleanliness, economic efficiency and securing stability of the field of view. 3.2.3 Enhancement items Enhancement items include easy installation, re-installation and removal of endoscope robots, high availability (troubleproof), easy operation and easy installation and removal of endoscopes during surgery. Easy installation, re-installation and removal of endoscope robots mean easy preparation for surgery and clean up, leading to improved safety. When emergency situations such as the failure of an endoscope robot, occurs, it is preferable that the endoscope robot is rapidly removed from the operation field and the surgery can be switched to traditional abdominal surgery. Since it takes time to install large endoscope robots and which need sterilization drapes, the dimension of endoscope robots or methods to secure cleanliness influences the ease of installation, re-installation and removal of endoscope robots. It is necessary to clean the lens at the tip of an endoscope several times during surgery because of blood, mists or tarnish. A function that the endoscope can be easily installed or removed to or from the robot is important to secure stable field of view. A human camera assistant can clean the lens of an endoscope for 20 sec. during surgery; therefore, the same performance is required for endoscope robots.

10

Robot Surgery

Operability of endoscope robots depends on System A. To avoid malfunctions it is preferable that System A with which surgeons directly give instructions to the robots, can be viscerally operated and can operate endoscope robots freely without using major equipment. The key to optimize LoopSAB is enhancement items of System A. It is preferable that endoscope robots be designed considering affordance and the directions on how to use the endoscope, be quickly and easily understood. It is also preferable that special training or skills are not necessary to use endoscope robots and people using them for the first time can use them easily. 3.2.4 Others The endoscope robots shall be designed so as not to be regarded as an alternative to the human camera assistant, but as an expansion of the surgeon’s skill. The surgeons should be made to feel comfortable; reassuring them that they will always be in control of the robots. It is necessary that surgeons viscerally understand all movement of the robots. Finally, it is understood that developing endoscope robots is not to imitate the hand movements of surgeons. The work done by surgeons follows the hand movement of humans; movement that is not suitable for robots. Upon developing endoscope robots, the goals shall be correctly specified, considering the optimized mechanism, or optimized system to obtain the goals and how to optimize each interaction group (LoopSAB and LoopSPB). 3.3 Implementation example of endoscope robot This section describes P-arm (disposable endoscope positioning robot) that we developed as an implementation example of endoscope robots. 3.3.1 Basic concepts We mainly focus on "safety", "cleanliness" and "usability" and have defined the basic concept of endoscope robots as follows: • The robots are equipped with a mechanism that if the endoscope robot, coming into contact with patients or doctors, applies a force that may cause harm, a structure that joins of the mechanism manipulator is dislocated and the force is mechanically released. Even if the joints of the manipulator are dislocated, the endoscope can be positioned (safety). • Parts that operate in clean fields shall be disposable. Disposable parts enable "secure cleanliness" and "warranty of quality of endoscope robots". Since maintenance is unnecessary, inconvenience to the medical front can be reduced (cleanliness) (quality: safety). • Endoscope robots shall be compact and lightweight. Endoscope robots shall weight less than the endoscopes (usability). • Endoscope robots are mounted on the surgical table. A mechanism which can freely change endoscope robots’ position and posture on a surgical table according to surgical targets is equipped (usability). • Generally commercially available endoscopes (direct-view endoscope and obliqueviewing endoscope) can be operated (usability). The critical matter of having endoscope robots that can be disposable is dependent upon the economic efficiency of the endoscope robots. Disposable endoscope robots require that they

Classification, Design and Evaluation of Endoscope Robots

11

can be manufactured at a competitive cost. As a method to realize endoscope robots manufacture at a competitive cost, we decided that "the interface and control equipment of the endoscope robots shall be used repeatedly, and the manipulators used in the clean fields, are to be disposed of after each surgery". 3.3.2 Mechanism of endoscope robot Fig. 5 shows the endoscope robot that we developed. System A of this robot is composed of a joystick interface and controller (control equipment). System B is composed of a disposable manipulator and general endoscopic device. The disposable parts are the manipulator, the tube and cylinder which send water to an actuator shown in Fig. 6. Since this endoscope robot was developed while System B was studied and developed, the joystick interface was used as a human machine interface so that System B could be easily evaluated and discussed. Human machine interfaces of this robot include automatic operation, voice recognition and a touch screen. Their explanation will be omitted.

Fig. 5. System configuration

Fig. 6. Disposable part

12

Robot Surgery

In our endoscope robot, the manipulator is composed of the Stewart-Gough Platform (six degrees of freedom parallel mechanism) (Tsai, 1999) and a linear actuator we developed and which can be sterilized is used for each element of the parallel mechanism. Our endoscope robot uses redundant six degrees of freedom. There have been some opinions that redundant degrees of freedom are unnecessary from the point of view of safety. This is because the runaway of a controller leads to unexpected movement of a manipulator since many of the endoscope robots developed so far use a serial mechanism or parallel linkage mechanism. Even if one of the actuators goes out of control, the parallel mechanism can suppress the runaway actuator with the other actuators; therefore, redundant degree of freedom will lead to safety. Hence, we selected six degrees of freedom of parallel mechanism focusing on safety. The parallel mechanism uses a smaller space with movement and can be more compact, trimmed weight and simplified, causing low cost compared to the serial mechanism when a tool (including an endoscope) operates in the narrow space such as in the human abdomen. Although high speed and accuracy are noticeable advantages in the parallel mechanism, we pay more attention to safety than high speed or high accuracy. To enhance ease of installing the endoscope robot, we used a method where it can be installed to the surgical bed using a general abdominoscope holding arm which surgeons are familiar with, instead of using an installation table exclusively for endoscope robots. The advantages to this method are that medical staffs do not have to learn or have training on a new installation method and the endoscope robots can be easily installed or re-installed. Since the existing arm is used, development cost can be reduced, resulting in a competitive cost. As a method for attaching the endoscope to the manipulator, we developed a way by using a permanent magnet. This method enables the endoscope to be installed during surgery and then, to possibly be removed during the same surgery, for cleaning the lens of the endoscope, resulting in securing the stability of the field of view (Fig.7). We have developed a medical-use hydraulic disposable linear actuator for endoscope robots. Since this actuator can be sterilized and is disposable, it can be used in clean fields of surgery, without previous sterilizating. This actuator, supplying air of 0.4MPa from the tube to the actuator, applies force to a direction where an actuator is stretched continuously and the water is sent from the cylinder or pump installed outside of the clean field through the tube. Consequently the amount of the water pressure is controlled to shrink the actuator. It

Fig. 7. Endoscope installation and removal mechanism using a permanent magnet

Classification, Design and Evaluation of Endoscope Robots

13

Fig. 8. Hydraulic linear actuator is completely safe as there is no possibility of ground leakage in the clean field. This actuator measures 185.0 mm in length and 112.5 mm in amount of extension. This actuator maximally stretches when no control is applied to the cylinder (Fig. 8). When it is mounted in a robot, an endoscope is outstretched when no control or setting is performed (default) to the robot. Before surgery, a site for an endoscope is made on the patient’s body, an endoscope is inserted into the site and the internal cavity is surveyed with the widest vision; therefore, providing a wide vision as a default can make settings easier and more efficient. Since force is applied to a direction where the endoscope is kept away from viscera, safety is improved. As described above, the parallel mechanism is very safe. There is no chance of electrification and force is applied to a direction where an endoscope is kept away from the viscera all the time, resulting in extreme safety. As a method to improve the safety of an endoscope further, "shock absorber" and "up to three emergency stop switches" are added. The shock absorber, a permanent magnet spherical bearing is used for connection between the end plate of the manipulator and each actuator. This disconnects the actuators from the endplate and absorbs the shock when an endoscope interferes with organs or the manipulator contacts with a doctor (Fig.9). Since the endoscope robot has redundant six degrees of freedom, four degrees of freedom necessary for the endoscope operation is secured even though up to two actuators are dislocated. Actuators dislocated due to shock can be reinstalled at the original position with a single movement due to the permanent magnet spherical bearing. As independent and different systems, three emergency stop devices can be installed. We prepared two kinds of emergency stop devices. One of them is a pushbutton type installed near the joystick and is used when a camera assistant performs an emergency stop. The other one are foot pedals installed under the foot of the surgeon and assistant. Either of them could operate in case of emergency. Each parameter of the manipulator is described below. These parameters are set for laparoscopic cholecystectomy. • Dimension: Base plate radius: 48.5 mm, end plate radius: 63.75 mm, height when all actuators contract: 207 mm • Weight: About 580 g (The weight of endoscope and camera is not included.) • Movement: Insertion/retraction: 112.5 mm, movable maximum range: 26 deg • Movement speed of actuators: 8 mm/sec at a maximum

14

Robot Surgery

Fig. 9. Shock Absorber

4. Evaluation methods of endoscope robots 4.1 Evaluation methods of endoscope robots Endoscope robots are evaluated using the information flow of LoopSAB and LoopSPB shown in Fig. 2. At the design stage, LoopSAB is evaluated and LoopSPB is mainly evaluated for test models. At this stage, the evaluation of each system in the LoopSAB is important and it is necessary to evaluate surgery results while facing up patients in the LoopSPB during the test model stages. For LoopSPB, information quality, information density, the period when information is output, stability of the Loop, each element of the surgeons, patients and manipulators are evaluated. Information quality indicates the image quality taken by the endoscope, information density indicates the range of the field of view, and the period when the information is output means the surgery time. The state of the surgeons is evaluated by the psychological stress of the surgeons who use the robot. The state of the patients is evaluated by the degree of perfection of the surgery and the state of manipulators is evaluated by the amount of space occupied for movement and the operation experiments over a long period of time. The followings are details of experiments of test models of endoscope robots with attention to information flow and their evaluation. • in-vitro experiments using animals or human organs: Whether or not the range of the field of view of the endoscope robots (operation range) is sufficient is evaluated. Also, in order to check whether or not the manipulators will obstruct the movement of the surgeons during surgery, the amount of space used when the manipulators operate is evaluated. In addition, the psychological stress of the surgeons who use endoscope robots is evaluated. In this experiment, the evaluation standard is if endoscope robots can be used for laparoscopic cholecystectomy. Surgery time and degree of perfection of the surgery are also evaluated. Pig livers with cholecyst are mainly used in this experiment (amount, quality and period of information and each element). • in-vivo experiment using animals: Details of the evaluation is the same as in in-vitro experiments where animals or human organs are used. In these experiment, fluctuation due to bleeding or breathing, particular to a living body, which cannot be evaluated in in-vitro experiment are evaluated (amount, quality and period of information and each element) • Clinical test: Comprehensive evaluation is performed using endoscope robots for laparoscopic cholecystectomy of a human patient (amount, quality and period of information, each element).

Classification, Design and Evaluation of Endoscope Robots

15

•

Operation experiments over a long period of time: Durability of endoscope robots is evaluated. As an index time for the extensive operation experiment, we set the duration length, for three times the length of time that a manipulator is continuously used without maintenance (each element). • Setup experiment: To evaluate if LoopSPB is easily constructed, the length of time for endoscope robot setup is evaluated. Whether medical staff who are using the endoscope robots for the first time can easily set up the robot without error is also evaluated (Loop stability) • Endoscope lens cleaning experiment: Quality or stability of information in the LoopSPB depends on the cleanliness of the endoscope’s lens. During in-vitro or in-vivo experiments, the time required for cleaning the endoscope lens and how easily the lens can be cleaned is evaluated. The index time for cleaning is 20 sec (quality and stability of information) • Correspondence experiment in emergencies: Assuming emergency situations such as an endoscope robot becoming out of control, the time required to switch from the surgery using the endoscope robot to surgery without the endoscope robot being used including halting and removal of the endoscope robot is evaluated (Loop stability). • Evaluation of cleanliness of the endoscope robots: Quality of cleanliness is evaluated after cleaning or sterilization (each element) For evaluation of LoopSAB, the strength of the endoscope robots, the operation range, the space required to operate the manipulators and the accuracy of movement with the human interface are evaluated during computer simulations at the design stages. The details of each evaluation methods are described below. 4.2 in-vitro experiment using pig livers with a cholecyst Laparoscopic cholecystectomy is normally used to evaluate endoscope robots [Yen et al., 2006, FDA, 2006]. This experiment frequently uses pig organs, not human organs. There are problems in ethical issues when human organs are used and pig organs have a relatively similar structure to human organs anatomically. This experiment simulates the environment by using a liver with a cholecyst to reproduce pseudo in-vivo environment and laparoscopic cholecystectomy where the cholecyst is removed from the liver. The experiment is performed in two cases where a camera assistant operates an endoscope and where a robot operates an endoscope and the results are compared. Livers equal to three times the number of experiments are prepared. Among the livers, the ones whose shapes and level of difficulty of surgery are similar are selected. The livers are placed in a surgery training box where an abdominal cavity is simulated to reproduce pseudo in-vivo environment. As examples, Fig. 10 shows an in-vitro experiment using a pig organ with P-arm as an endoscope robot and Fig. 11 shows an example of the device installation. Next, specific details of evaluation are described. • Whether images taken by an endoscope operated by a robot provides the same range of images as those taken by an endoscope operated by a camera assistant is evaluated. We aim at there being no difference in the images taken by endoscopes operated by robots and those operated by camera assistants. Surgeons evaluate whether there is no essential difference in a scale of enlargement of the image taken by endoscopes, the range of field of view and the angle of view for the surgery. Cholecystectomy is separated into three phases, bile duct treatment, cholecyst (body area) removal and treatment of the bottom of the cholecyst. Fig. 12 shows images taken by an endoscope in each phase during the experiment.

16

Robot Surgery

Fig. 10. in-vitro experiment

Fig. 11. Installation of devices in in-vitro experiment

(a)

(b)

(c)

Fig. 12. Images taken by an endoscope during in-vitro experiment: a) Bile duct treatment, b) cholecyst (body area) removal, c) treatment of the bottom of the cholecyst •

Whether the space occupied by the manipulators obstructs the surgery or not is evaluated. Surgeons operate while they watch a monitor where the images are taken by an endoscope. If manipulators widely move and obstruct the hands of the surgeons, it is difficult for the surgeons to know the movement of the manipulators in advance. Manipulators and the hands of the surgeons are videoed during this experiment to

Classification, Design and Evaluation of Endoscope Robots

•

•

17

make sure that there is no interference. After the experiment, we investigate whether the manipulators had interrupted the surgeons with questionnaires. Surgeons compare cases where the camera assistant operates the endoscope and where the robot operates the endoscope and evaluate whether the operation of an endoscope by the robot is not inferior to that of the camera assistant. Surgeons also evaluate the degree of perfection of the surgery. Surgeons’ psychological stress during the experiment is measured when a camera assistant operates the endoscope and when a robot operates the endoscope. Whether surgeons have psychological stress or not by using an endoscope robot during surgery is objectively evaluated. The stress is measured using surgeons’ salivary component and acceleration pulse wave. To evaluate whether surgeons are subjected to psychological stress due to the use of an endoscope robot during surgery, surgeons’ saliva and acceleration pulse wave before and after surgery are measured. Then, they are analyzed and evaluated. Saliva cortisol and saliva α amylase are measured. The details are in a chapter of the In-Tech book"Advances in Human-Robot Interaction" (Taniguchi et al., 2009) for reference.

4.3 in-vivo experiment using a pig Efficiency of endoscope robots are evaluated by performing a laparoscopic cholecystectomy on a pig based on problems including bleeding or fluctuation due to the patient’s breathing, which is particular to living bodies. It is better to evaluate laparoscopic assisted distal gastrectomy and laparoscopic anterior resection as an advance surgery which needs a wide range of view. These procedures require a wide operation range and do not use endoscope robots since endoscope robots will interrupt surgery unless they are compact. As an example, Fig. 13 shows an in-vivo experiment where a pig is used and P-arm is used as an endoscope robot and Fig. 14 shows the installation location of devices. This laparoscopic cholecystectomy started when a trocar was placed on an anesthetized pig and cholecystectomy was performed and ended when the insertion site was sutured. The process during surgery was the insertion of an endoscope, adjustment of the range of view, movement of the field of view and removal of the cholecyst (gallbladder). Fig. 13 shows an in-vivo experiment with one surgeon and one camera assistant and a fixing supporting arm is used to hold the liver instead of a surgery assistant.

Fig. 13. in-vivo experiment

18

Robot Surgery

Fig. 14. Device installation for in-vivo experiment Evaluation items for this experiment are the same in the in-vitro experiment using a pig liver with cholecyst described in section 4.2. The time for surgery to be measured is from when surgery started with the forceps inserted into the abdominal cavity to when the cholecyst is removed outside of the abdominal cavity (including robot setup time). Fig. 15 shows images of bile duct treatment, cholecyst (body area) removal and removal of the bottom of cholecyst taken by an endoscope. Surgeons evaluate scale of enlargement, angle of field of view and range of view necessary for cholecystectomy. Fig. 16 shows images of laparoscopic assisted distal gastrectomy taken by an endoscope. Fig.17 shows laparoscopic anterior resection. The number from 1 to 9 in Fig. 16 and 17 indicates progress of procedures.

(a)

(b)

(c)

Fig. 15. Images taken by an endoscope during in-vivo experiment A)Laparoscopic image of the bile duct in an experiment, b)Laparoscopic image of the body of gallbladder in an experiment , c)Laparoscopic image of the fundus of gallbladder in an experiment

Classification, Design and Evaluation of Endoscope Robots

Fig. 16. Laparoscopic image of laparoscopic assisted distal gastrectomy (LADG)

Fig. 17. Laparoscopic image of laparoscopic low anterior resection

19

20

Robot Surgery

4.4 Robot setting experiment, switching experiment from endoscope robot operation to manual operation assuming emergencies such as failure of a robot, endoscope lens cleaning experiment Details of evaluation items on LoopSPB stability and quality of information are described below. • Robot setting experiment: The time it takes the surgeons to install the manipulator to the surgical table, the endoscope to the manipulator, and the endoscope to be positioned, is measured. This experiment is performed several times and the learning curve is analyzed and evaluated. It is desirable that the setup be easily performed in a short amount of time and that the time required for setting up should be shorter after the surgeons have become accustomed to the operation (LoopSPB stability) • Switching experiments from endoscope robot operation to manual operation: This experiment is performed to simulate handling when an emergency such as the failure of an endoscope robot occurs. The following time was measured; the endoscope robot was made to stop by pressing the emergency stop switch and the manipulator was moved, by the holding arm, to an area where the robot does not interrupt the surgery. Then, a normal surgery started where a human camera assistant positions the endoscope holding position. It is desirable that the above procedure is performed within 30 sec. (LoopSPB stability) • Endoscope lens cleaning experiment: The following time is evaluated; the endoscope is removed from the robot, the endoscope lens is cleaned, the endoscope is re-installed to the endoscope robot and the field of view is secured by the endoscope. The endoscope lens cleaning time when a human camera assistant operates the endoscope is about 20 sec. It is desirable that the lens cleaning time with the robot is also within 20 sec. (quality of information, LoopSPB stability) 4.5 Operation experiment over a long period of time To discuss the durability of endoscope robots, continuous operation of the robot is performed for longer than three times that of an actual surgery. In this experiment, an endoscope, camera head and optical fibre cable are installed to an endoscope robot and the endoscope is inserted into the trocar which is installed to a human body model to simulate the usage environment of an actual surgery. For the robot movement, a control program

Fig. 18. Operation experiment over a long period of time

Classification, Design and Evaluation of Endoscope Robots

21

developed for operation experiments over a long period of time moves four degree of freedom where speed and movable range is variously changed. Fig. 18 shows this experiment using P-arm as an example. 4.6 Evaluation on cleanliness Sterilization methods include sterilization drape, gaseous sterilization, autoclave sterilization and electron-ray beam sterilization. When the sterilization drape is used, it is necessary to evaluate whether the sterilization drape does not tear due to the robot operation or the contact with medical staff. When gaseous sterilization, autoclave sterilization or electron-ray beam sterilization is used, specialized institutions evaluate and discuss cleanliness. 4.7 Presenting at exhibitions Presentations of test models of endoscope robots at medical institute exhibitions should be made to gather opinions from others in the medical field, such as doctors, nurses or ME, It would also be advisable to make presentations of test models of endoscope robots at engineering exhibitions and to obtain opinions from the point of view of engineers.

5. Development into the future Generally speaking, medical robotics is an academic framework of robots which provide "new eyes and hands" beyond the ability of human surgeons. Medical robots can be classified into treatment robots (surgical CAD/CAM systems), which perform surgery with image guidance and surgical assistant robots (surgical assistant systems), which assist in the treatment by the surgeons. Endoscope robots are classified into the surgical assistant robot [34]. This chapter treated endoscope robots as an interactive media and described the design and evaluation methods of endoscope robots. Our goal was to get a better understanding of endoscope robots while considering endoscope robots as interactive media, since endoscope robots closely interact with humans and assist with the surgery, coming in contact with patients around surgeons. Research and development of endoscope robots is striving for maintenance-free, compact, lightweight, automated, safe, clean and low cost endoscope robots; for the purpose of applying them to advanced surgeries. Diversion to NOTES of endoscope robots or single port surgery is not envisioned in the future. It is possible to make endoscope robots operate surgery devices such as forceps instead of endoscopes; however, easy diversion is a mistake. The reason is that methods to secure the required safety, accuracy or speed are totally different between the operation of an endoscope and the operation of forceps. Development of endoscope robots has been well-established for the last 20 years and endoscope robots have been commercialized and active on the medical front. This chapter is written hoping that further study and development of endoscope robots spreads to all medical institutions where endoscopic surgery is performed and that endoscope robots will become partners with surgeons, for the benefit of many precious lives.

6. Acknowledgement This research was supported in part by “Special Coordination Funds for Promoting Science and Technology: Yuragi Project” of the Ministry of Education, Culture, Sports, Science and

22

Robot Surgery

Technology, Japan, Grant-in-aid for Scientific Research (A) (No. 19206047 ) of the Japan Society for the Promotion of Science.

7. References Kobayashi, E.; Masamune, K.; Sakuma, I.; Dohi, T. & Hashimoto, D. (1999). A New Safe Laparoscopic Manipulator System with a Five-Bar Linkage Mechanism and an Optical Zoom. Computer Aided Surgery, Vol.4, 182-192. Tanoue, K.; Yasunaga, T.; Kobayashi, E.; Miyamoto, S.; Sakuma, I.; Dohi, T.; Konishi, K.; Yamaguchi, S.; Kinjo, N.; Takenaka, K.; Maehara Y. & Hashizume, M. (2006). Laparoscopic cholecystectomy using a newly developed laparoscope manipulator for 10 patients with cholelithiasis. Surgical Endoscopy, Vol.20, No.5, 753-756, ISSN 0930-2794 (Print) 1432-2218 (Online). Sackier, J. M. & Wang, Y. (1994). Robotically assisted laparoscopic surgery form concept to development. Surgical Endoscopy, Vol.8, No.1, 63-66, ISSN 0930-2794 (Print) 14322218 (Online). Finlay, P. A. (2001). A Robotic Camera Holder for Laparoscopy. Proceedings and Overviews of ICAR2001 Workshop 2 on Medical Robotics. Proceedings of the 10th International Conference on Advanced Robotics, 129-132. Aug. 2001, Budapest, Hungary Nishikawa, A. ; Ito, K. ; Nakagoe, H. ; Taniguchi, K. ; Sekimoto, M.; Takiguchi, S. ; Seki, Y. ; Yasui, M. ; Okada, K. ; Monden, M. & Miyazaki, F. (2006). Automatic Positioning of a Laparoscope by Preoperative Workspace Planning and Intraoperative 3D Instrument Tracking. MICCAI2006 Workshop proceedings, Workshop on Medical Robotics:Systems and Technology towards Open Architecture, 82-91. Nishikawa, A.; Nakagoe, H.; Taniguchi, K.; Yamada, Y.; Sekimoto, M.; Takiguchi, S.; Monden, M. & Miyazaki, F. (2008). How Does the Camera Assistant Decide the Zooming Ratio of Laparoscopic Images? -Analysis and Implementation-. Proceedings of the 11th International Conference on Medical Image Computing and Computer Assisted Intervention (MICCAI 2008) , New York, USA, Sep.2008. Hurteau, R.; DeSantis, S.; Begin, E. & Gagner, M. (1994). Laparoecopic Surgery Assisted by a Robotic Cameraman: Concept and Experimental Results. Proceedings of IEEE International Conference on Robotics & Automation, 2286 – 2289. Taylor, R. H.; Funda, J.; Eldridge, B.; Gomory, S.; Gruben, K.; LaRose, D.; Talamini, M.; Kavoussi, L. & Anderson, J. (1995). A telerobotic assistant for laparoscopic surgery. IEEE Engineering in Medichine and Biology, vol.14. no.3, 279 – 288. Munoz, V. F.; Vara - Thorbeck, C.; De Gabriel, J. G.; Lozano, J. F.; Sanchez-Badajoz, E.; Garcia-Cerezo, A.; Toscane, R. & Jimenez-Garrido, A. (2000). A medical robotic assistant for minimally incasive surgery. Proceedings of IEEE International Conference on Robotics & Automation, 2901 – 2906. Munoz, V. F.; Gomez De Gabriel, J.; Garcia-Morales, I.; Fernandez-Lozano, J. & Morales, J. (2005). Pivoting motion control for a laparoscopic assistant robot and human clinical trials. Advanced Robotics, vol.19, no.6, 694 – 712. Polet, R. & Donnez, J. (2004). Gynecologic laparoscopic surgery with a palm-controlled laparoscope holder. The Journal of the American Association of Gynecologic Laparoscopists, 73–78. Mizhuno, H. (1995). Robotic Endo-Surgery System. Robot symposium 5th, 115 - 118 (in Japanese)

Classification, Design and Evaluation of Endoscope Robots

23

Nishikawa, A.; Hosoi, T.; Koara, K.; Negoro, D.; Hikita, A.; Asano, S.; Kakutani, H.; Miyazaki, F.; Sekimoto, M.; Yasui, M.; Miyake, Y.; Takiguchi, S. & Monden, Morito. (2003). FAce MOUSe: A Novel Human-Machine Interface for Controlling the Position of a Laparoscope. IEEE Transactions on Robotics and Automation, vol.19, no. 5, 825-841. Funda, J.; Gruben, K.; Eldridge, B.; Gomory, S. & Taylor R. H. (1995). Control and evaluation of a 7-axis surgical robot for laparoscopy. Proceedings of IEEE International Conference on Robotics & Automation, 1477-1484. EndoControl (2009). http://www.endocontrol-medical.com/ [accessed October 10, 2009 ] Long, J. A.; Cinquin, P.; Troccaz, J.; Voros, S.; Berkelman, P.; Descotes, J. L.; Letoublon, C. & Rambeaud. J. J. (2007). Development of Miniaturized Light Endoscope-Holder Robot for Laparoscopic Surgery. Journal of Endourology, vol.21, no8, 911-914. Lee, Y. J.; Kim, J.; Ko, S. Y.; Lee, W. J. & Kwon, D. S. (2003). Design of a Compact Laparoscopic Assistant Robot : KaLAR. Proceedings of the International Conference on Control Automation and Systems, 2648-2653. Buess, G. F.; Arezzo, A.; Schurr, M .O.; Ulmer, F.; Fisher, H.; Gumb, L.; Testa, T. & Nobman, C. (2000). A new remote-controlled endoscope positioning system for endoscopic solo surgery The FIPS Endoarm. Surgical Endoscopy, vol.14, 395 - 399. Kimura, T.; Umehara, Y. & Matsumoto, S. (2000). Laparoscopic cholecystectomy performed by a single surgeon using a visual field tracking camera. Surgical Endoscopy, vol.14 , 825 - 829. Kobayashi, E.; Sakuma, I.; Konishi, K.; Hashizume, M. & Dohi, T. (2004). A robotic wideangle view endoscope using wedge prisms. Surgical Endoscopy, vol.18, 1396-1398. Yamauchi, Y.; Yamashita, J.; Fukui, Y.; Yokoyama, K.; Sekiya, T.; Ito, E.; Kanai, M.; Fukuyo, T.; Hashimoto, D.; Iseki, H. & Takakura K. (2002). A dual-view endoscope with image shift. Proceedings of CARS2002, 183 - 187. Nakaguchi, T.; Makino H.; Igarashi T.; Kamimura K.; Tsumaru N. & Miyake Y. (2005). An Automatic Tracking and Zooming System for Laparoscopic Surgery. Transactions of Japanese Society for Medical and Biological Engineeing, vol. 43, no. 4 685-693. Taniguchi, K.; Nishikawa, A.; Yohda, T.; Sekimoto, M.; Yasui, M.; Takiguchi, S.; Seki, Y.; Monden, M. & Miyazaki, F. (2006). COVER: Compact Oblique Viewing Endoscope Robot for laparoscopic surgery. Proceedings of CARS2006, 207. Sekimoto, M.; Nishikawa, A.; Taniguchi, K.; Takiguchi, S.; Miyazaki, F.; Doki, Y. & Mori, M. (2009). Development of a Compact Laparoscope Manipulator (P-arm). Surgical Endoscopy, ISSN0930-2794 (Print) 1432-2218 (Online) Prosurgics (2009). http://www.freehandsurgeon.com/about.php [accessed October 10, 2009] Sarkar, S.; Abolhassani, M. D.; Farahmand, F.; Ahmadian, A. R. & Saber, R. (2009). Research Activities at the Research Centre for Science and Technology in Medicine, Iranian J Publ Health, vol. 38, suppl. 1, 153-157. Deshpande, S. (2004). http://www.lapindianrobot.com/robot1.htm [accessed October 10, 2009 ] Szold, A.; Sholev, M.; Matter, I. (2008). Smart and slim laparoscopic robotic assistant. Proceedings of the 20th International Conference of Society for Medical Innovation and Technology (SMIT2008), 211.

24

Robot Surgery

NGT, (2009). http://www.ngtnazareth.com/viewProject.asp?i=14 [accessed October 10, 2009] Rininsland H. (1999). ARTEMIS: A telemanipulator for cardiac surgery. EuropeanJournal of Cardio-thoracic Surgery, vol.16, suppl. 2, 106-111. KIT, (2009). http://www.iai.fzk.de/www-extern/index.php?id=352&L=1 [accessed October 10, 2009 ] FZK, (2009). http://bibliothek.fzk.de/zb/Videolabor/hbm/Tabellen/Jahrg_00_fix.htm [accessed October 10, 2009 ] Graur, F.; Plitea, N.; Vlad, L.; Pisla, D.; Vaida, C.; Furcea, L. & Neagos, H. (2009). A Muresan, Experimental laparoscopic cholecystectomy using paramis parallel robot, Proceedings of the 21st International Conference of Society for Medical Innovation and Technology (SMIT2009). Leveson, N. G. & Turner, C. S. (1993). An Investigation of the Therac-25 Accidents. IEEE Computer, vol.26, no.7, 18-41. Taylor, R. H. & Stoianovici, D. (2003). Medical Robotics in Computer-Integrated Surgery IEEE Transactions on Robotics and Automation, vol. 19, no. 5, 765-781. Tsai, L. W. (1999). Robot Analysis: The Mechanics of Serial and Parallel Manipulators. Wiley. Yen, D.; Roxolana, H. & Neil, O. (2006). US FDA regulation of computerized and robotics surgical systems. Proceedings of CARS2006. FDA, (2006). http://www.jscas.org/guideline/FDA_CARS2006_Talk.pdf [accessed October 10, 2009] Taniguchi, K.; Nishikawa, A.; Sugino, T.; Aoyagi, S.; Sekimoto, M.; Takiguchi, S.; Okada, K.; Monden, M. & Miyazaki, F.(2009). Method for objectively evaluating psychological stress resulting when humans interact with robots. In-Tech book: Advances in Human-Robot Interaction, IN-TECH Education and Publishing.

2 Extreme Telesurgery Tamás Haidegger and Zoltán Benyó

Budapest University of Technology and Economics Hungary 1. Introduction The technological development of the last decades resulted in the rise of entirely new paradigms in healthcare. Within interventional medicine, first Minimally Invasive Surgery (MIS) and later robot-assisted surgery redefined the standards of clinical care. The concept of telemedicine dates back to the early 1970s, and in the late ‘80s, the idea of surgical robotics was born on the principle to provide active telepresence to surgeons. With the help of mechatronic devices physicians were first able to affect remote patients with the Green telepresence system in 1991. Soon after, many new research projects were initiated, creating a set of instruments for telesurgery. Visionary surgeons created networks for telesurgical patient care, demonstrated trans-continental surgery and performed procedures in weightlessness. The U.S. Army has always been interested in this technology for the battlefield, and currently the Telemedicine and Advanced Technology Research Center (TATRC) enforces research to test and extend the reach of remote healthcare. However, due to the high business risk, not many surgical robots succeeded to pass clinical trials, and barely some become profitable. Beyond intercontinental operations, probably the most extreme field of application is medical support of long duration space missions. With a possible foundation of an extraplanetary human outpost either on the Moon or on Mars, space agencies are carefully looking for effective and affordable solutions for life-support and medical care. Teleoperated surgical robots have the potential to shape the future of extreme healthcare. Besides the apparent advantages, there are some serious challenges of robotic healthcare that must be dealt with. The primary difficulty with teleoperation over large distances or beyond Earth orbit is communication lag time. Even in the case of intercontinental teleoperation—assuming the usage of commercial communication lines—latency can be in the order of several hundred milliseconds. While military satellite networks show better performance, these are not accessible for regular use. Surgery robot control communication protocols must be robust and false-tolerant, while advanced virtualization and augmented reality techniques should help the human operators to better adapt to the special challenges. A novel virtual reality based, extended surgical environment control concept is proposed. To meet safety standards and requirements in space, a three-layered architecture is recommended to provide the highest quality of telepresence with the provisional exploration missions. Today’s extreme telesurgery concept may well find a way to common civil applications for the benefit of many patients.

26

Robot Surgery

2. Concept of telemedicine and telesurgery 2.1 Advanced medical technology Telemedicine allows physicians to treat patients geologically separated from themselves. Pilot networks have been installed and tested in the second half of the 20th century, and the first intercontinental procedures were conducted in the 1990s (Rosser et al., 2007). Telemedicine in general can be broken down to three main categories based on the timing and synchrony of the connection. Store-and-forward telemedicine means there is only one way communication at a time, the remote physician evaluate medical information offline, and sends those back to the original site at another time. Next, remote monitoring enables medical professionals to collect information about patients from a distance with different modality sensors. Finally, interactive telemedicine services provide real-time communication between the two sites, which might be extended with different forms of interactions, achieving real telepresence. According to the functionality, three levels of telepresence can be defined within telemedicine based on the actual capabilities of the physician at the remote location. If instant and unlimited access is provided to the medical site, that is real-time teleoperation (or telesurgery, in the case of surgical procedure). Telementoring means the use of telecommunications technology— including the internet—to support and guide locally operating medics. Consultancy telemedicine (or telehealth consultancy) requires only limited access to the remote site, and as a result, the distant group cannot use real-time services or information updates. The advantages of telemedicine are various, in the case of short-distance operations, the technology involved can mean great added value, such as an externally controlled tool holder or surgical robot (Herman 2005). In long-distance telementoring, the time/cost effectiveness and the provided higher level of medical care are the most important benefits, while in extreme telemedicine, such as space exploration it may be the only available form of adequate medical aid.

Fig. 1. Integration of different modality feedback information to the concept of telesurgery. Interaction is only possible through a system of sensors and human-machine interfaces. Modified from (Hager et al., 2008). Beyond the possibility to observe the remote site, the quality of telepresence has always been paramount for the surgeons to be able to perform a procedure. The availability of

Extreme Telesurgery

27

different modalities combined, such as 2D/3D visual, tactile/haptic, acoustic, etc. has been proved to dramatically increase human performance. Figure 1 shows the integration of different modalities to the control diagram of telesurgery concept. Currently, the dominant form of sensory feedback is visual, as that provides highest density of information. The resolution of video cameras has been increasing in the past years, and currently full HD resolution is available with most systems, accompanied with a high fidelity 3D stereoscopic view. Although haptic feedback was provided with the first robot prototypes, the commercially available systems miss this modality due to the complexity (and additional cost) of the hardware and the challenges to provide life-like tactile feedback to the surgeon. 2.2 History of telehealth There have been several experiments conducted in the past two decades to verify the usability of remote health care paradigms. Due to the fact that surgeons navigate based on a camera image, telementoring techniques are well applicable in laparoscopy, MIS. It is considered to be one of the most important breakthroughs in medicine in the past decades (Ballantyne, 2007). In 1997, laparoscopic colectomy and laparoscopic Nissen fundoplications were the first procedures performed with the aid of professional telementoring, from over 8 km distance (Rosser et al., 1997). The same group performed the first international telementoring between the John Hopkins Medical Institute (Baltimore, MD) and Innsbruck, Austria and Bangkok, Thailand (Lee et al., 1998). In 1999, they telementored from Maryland five laparoscopic hernia repairs, performed on board of the USS Abraham Lincoln aircraft carrier in California (Cubano et al. 1999). Later, several intercontinental telementorig experiments have been performed, mainly from the USA to Italy, France, Singapore, Nepal and Brazil (Fabrizio et al., 2000). The U.S. Department of Defense (DoD) got interested in the feasibility of telesurgery even earlier; aimed to develop a system that allows the combat surgeons to perform life saving operations on wounded soldiers from a safe distance (Satava, 1995). The idea of robotic support in space dates back to the early ‘70s, proposed in a study for the National Aeronautics and Space Administration (NASA) to provide surgical care for astronauts with remote controlled robots (Alexander, 1973). This is particularly desirable, as the specific, high level medical education of the flight surgeons might be impossible to achieve. Proficiency in MIS, laparoscopic surgery requires extreme amount of practice, and maintenance of skills is only possible with continuous training.

3. Robotic telesurgery In most of the cases, mechatronic systems and cameras are the remote hands and eyes of the surgeon, and therefore key elements of the operation. Out of the 370 international surgical robotic projects listed in the Medical Robotic Database (MeRoDa, 2009), there are several dozens with the capability of teleoperation. In general, robots can be involved in medical procedures with differnet level of autonomy (Nathoo et al. 2005). Many of the developed systems only serve as a robust tool holding equipment, once directed to the desired position. Systems that are able to perform fully automated procedures—such as CT-based biopsy or drilling—are called autonomous, or supervisory controlled. (A human supervisor would always be present to intervene if deviation occurs compared to the surgical plan.) This can be combined with the classic tools of image guided surgery, once the robot is registered to the patient.

28

Robot Surgery

When the robot is entirely remote-controlled, and the surgeon is absolutely in charge of the motion of the robot, we call it a teleoperated system. These complex systems typically consist of three parts; one or more slave manipulators, a master controller and a sensory (e.g. vision) system providing feedback to the user. Based on the gathered visual (and haptic, acoustic, etc.) information, the surgeon guides the arm by moving the controller and closely watching its effect. By modifying the teleoperation control paradigm, we can introduce cooperative (also called compliant) control. It means that the surgeon is directly giving the control signals to the machine through a force sensor, performing hands-on operation. 3.1 First telesurgery systems Funded by the DoD, the first prototype of telesurgery robot was developed at Stanford Research International (SRI) (Menlo Park, CA) called the Green Telepresence System (Green et al., 1991). It was assembled by 1991, primarily aimed for open surgery. The idea to use it with MIS came with the rapid spread of laparoscopic technique. A series of ex-vivo and invivo trials were performed by 1995 (Bowersox et al., 1996). NASA Jet Propulsion Laboratory (JPL) (Pasadena, CA) also started to develop a system in the early times, and by 1993 they created the RAMS (Robot-Assisted Microsurgery System), targeting high-precision ophthalmic procedures (Schenker et al., 1995). Based on the experience at SRI and NASA, the Defense Advanced Research Projects Agency (DARPA) of DoD initiated the Trauma Pod project in 1994. The main goal was to “enhance battlefield casualty care by developing autonomous and semi-autonomous mobile platforms through the integration of tele-robotic and robotic medical systems. The initial phase has successfully automated functions typically performed by the scrub nurse and circulating nurse… The next phase of the program will develop methods for autonomous airway control and intravenous access... Finally, these systems will be miniaturized and incorporated into a tactical platform capable of operating in a battlefield or mass casualty environment.” (Trauma Pod, 2009). The robots developed with the help of DARPA have already been tested under extreme circumstances, in weightlessness and at NASA Aquarius underwater habitat. 3.2 Commercialized systems The most well known commercialized robots are the da Vinci Surgical System from Intuitive Surgical Inc. (Sunnyvale, CA) and the discontinued Zeus from Computer Motion Inc. (Santa Barbara, CA). While these robots inherited the structure and features that make them capable of performing telesurgical operations, most commonly they are used for on-site surgery. Their primary advantage is easing the complexity of laparoscopic procedures, providing better visualization, control and ergonomics to the surgeon, and higher precision to the patient. Presently, the market leader (and the only available) complete teleoperated robot is the da Vinci, created with roughly 500M USD investment. The patient side consists of two or three tendon-driven, 6+1 degree of freedom (DOF) slave manipulators. These are designed with a Remote Center of Motion (RCM) kinematics, resulting in an inherent safety regarding the stability of the entry port. The camera holder arm allows 3 DOF navigation controlled with the same master interface. The system provides high quality 3D vision with stereoendoscopes, adjustable tremor filtering (~6 Hz) and motion scaling (1:1 – 1:5).

Extreme Telesurgery

29

In 1995, Intuitive licensed technology from NASA, SRI, IBM and several universities, and by 1997, the first prototype—Lenny—was developed for animal trials. Next, Mona was made for the very first human trials involving vascular and gynaecological procedures in the Saint-BlasiusHospital (Dendermonde, Belgium) in March 1997. As the system was originally intended for cardio-vascular (beating-heart) surgery, specific clinical trials were performed in Paris and Leipzig in May 1998 (Ballantyne et al., 2004). Based on the initial experience, the market-ready version of the robot (named da Vinci honouring the great inventor) got advanced control and ergonomic features compared to the Mona. Final clinical tests began in 1999, and the U.S. Food and Drug Administration (FDA) approved the system for general laparoscopic surgery (gallbladder, gastroesophageal reflux and gynecologic surgery) in July 2000, followed by many other approvals. Once the system was on the market, Intuitive continued perfecting it, and the second generation—the da Vinci S—was released in 2006 (Figure 2). The latest version, the da Vinci Si became available in April 2009 with improved full HD camera system, advanced ergonomic features, and most importantly, the possibility to use two consoles for assisted surgery.

Fig. 2. Master controllers and the patient side manipulators of the new da Vinci Si surgical system. (Photo: Intuitive Surgical Inc.) Currently, there are more than 1300 da Vinci units around the world, ¾ of them in the U.S. The number of procedures performed is well over 300,000, the most successful application of the robot became prostatectomy. Around 70% of all radical prostate removal procedures were performed robotically in the U.S. in 2008. The concept of the da Vinci theoretically allows remote teleoperation, but that has not been the primary focus of Intuitive. The previous versions of the robot used a proprietary shortdistance communication protocol through optic fibre to connect the master and the slave, while the latest Si facilitates further displacement of the two units. In 2005, TATRC presented collaborative telerobotic surgery on animals with modified da Vinci consoles, being able to overtake a master controller with a remote one through public internet connection (Flynn, 2005). During the experiment, the average roundtrip latency was 500 ms from Denver to Sunnyvale, which was disturbing for the physicians. Another similar robot was the Zeus Telesurgical System developed by Computer Motion Inc. (Santa Barbara, CA). It was based on the AESOP (Automated Endoscopic System for Optimal Positioning) camera holder arm (FDA approved in December 1993). The Zeus received FDA clearance in 2001. The Zeus was controlled in master-slave setup, and used

30

Robot Surgery

UDP/IP (User Datagram Protocol over Internet Protocol) for communication. This facilitated various experimental telesurgery procedures as described later (Kumar & Marescaux, 2008). After long litigation with Intuitive over mutual intellectually property violations, the whole company was bought by Intuitive, and first the production, then the support of the Zeus system was suspended. 3.3 Light-weight prototypes Although some systems never got commercialized, they were created with the aim to facilitate extreme telesurgery. NASA JPL and MicroDexterity Systems Inc. (Albuquerque, NM) developed the RAMS (Robot-Assisted Micro-Surgery) system (Das et al., 1998). The RAMS consists of two 6 DOF arms, equipped with 6 DOF tip-force sensors, providing haptic feedback to the operator (Figure 3). It used the concept of telesurgery for control; however, the operator sat right next to the slave arms. The robot was originally aimed for ophthalmic procedures, especially for laser retina surgery. It is capable of 1:100 scaling (achieving 10 micron accuracy), tremor filtering (8-14 Hz) and eye tracking. Currently the prototype rests idle at JPL, as the project was discontinued.

Fig. 3. The RAMS robot developed at NASA JPL in laboratory trials and in-vivo animal tests in 1998. (Photo: NASA) Doctors and scientists at the BioRobotics Lab., University of Washington (Seattle, WA) have developed a portable surgical robot that can be a compromised solution to install on spacecrafts with its 22 kg overall mass (Rosen & Hannaford, 2006). The DARPA supported robot—called Raven—works along the same principle as the da Vinci. It has two articulated, tendon driven arms, each holding a stainless steel shaft for different surgical tools. It can easily be assembled even by non-engineers, and its communication links have been designed for long distance remote-control. The system has participated in multiple field tests, and now several units are being built for large scale clinical trials (Lum et al., 2009). Realizing the importance of a light, but stiff structure, SRI started to develop the M7 in 1998 (Figure 3.). The system weights only 15 kg, but able to exert significant forces compared to its size. It is equipped with two 7 DOF arms, motion scaling (1:10), tremor filtering and haptic feedback. The end-effectors can be changed very rapidly, and even laser tissue welding tool can be mounted. The controller has been designed to operate under extremely different atmospheric conditions, e.g. it only contains solid-state memory drives. The

Extreme Telesurgery

31

software of the M7 has been updated lately to better suit the requirements of teleoperation and communication via Ethernet link. The M7 performed the world’s first automated ultrasound guided tumor biopsy in 2007. The German Aerospace Center (DLR) Institute of Robotics and Mechatronics (Wessling, Germany) has already built several generations of light-weight robotic arms for ground and space applications. They have also taken part in many telerobotic space experiments in the past decades. The KineMedic and the most recent MIRO 7 DOF surgical robots are considered for real teleoperation—even in extreme locations—as one arm is only 10 kg and capably of handling 30 N payload with high accuracy (Hagn et al., 2008). Small scale, in-body robots offer great advantages, as they are always remote controlled, opening the possibility of spatial displacement of the physician from the patient. Engineers at the University of Nebraska (Lincoln, NE) together with the physicians of the local Medical Center developed a special mobile in-vivo wheeled robot for biopsy (Rentschler et al., 2006). Equipped with a camera, the coin-sized robot can enter the abdominal cavity through one small incision and move teleoperated around the organs. The robot is able to traverse the abdominal organs without causing any damage, therefore reduces patient trauma. More recently, the group has developed various swallowable robots that can be controlled with external magnets. The CRIM group at Scuola Superiore Sant'Anna (Pisa, Italy) leads a European Union FP7 founded international research collaboration to develop tethered, partially autonomous robots to perform surgery in the endolumen (Menciassi & Dario, 2009). Another EU project—Vector—aims for the creation of effective capsule robots for local surgical procedures throughout the GI tract (Eirik et al., 2009).

Fig. 4. The Zeus robot during the first intercontinental surgery, the colecystectomy was performed on the patient in Strasbourg from New York. (Photo: IRCAD)

4. Remarkable experiments 4.1 Long distance telesurgery The Zeus robot proved to be a solid platform to test and experiment different telesurgical scenarios. Between 1994 and 2003 the French Institut de Recherche contre les Cancers de l'Appareil Digestif (IRCAD) (Strasbourg, France) and Computer Motion Inc. worked together in several experiments to learn about the feasibility of long distance telesurgery and effects of latency, signal quality degradation. After six porcine surgeries, the first

32

Robot Surgery

transatlantic human procedure—the Lindbergh operation—was performed with a Zeus 7. September, 2001 (Marescaux et al., 2002). The surgeons were controlling the robot from New York, while the patient laid 7,000 km away in Strasbourg (Figure 4). Based on previous research (Fabrizio et al., 2000), it was estimated that the time delay between the master consol and the robot should be less than 330 ms to perform the operation safely, while above 700 ms, the operator may have real difficulties controlling the Zeus. A high quality, dedicated 10 Mbps ATM fibre optic link was provided by France Telecom, transmitting not just the control signals and video feedback, but also servicing the video conferencing facilities, and an average of 155 ms communication lag time was experienced. Out of that roughly 85 ms was the communication lag through the transmission, and 70 ms the coding and decoding of the video signals.

Fig. 5. Network Route Director (NRD) designed for CMAS by Bell research in 2002 to support the telesurgical network in Canada. In Canada, the world’s first regular telerobotic surgical service network was build and managed routinely between the Centre for Minimal Access Surgery (CMAS), a McMaster University Centre (Hamilton, Ontario) and a community hospital in North Bay some 400 km away, using the Zeus robot (Anvari, 2005). The average latency recorded was about 150 ms using commercial high-speed internet link Virtual Private Network (VPN) protocol (Figure 5). CMAS performed 22 telerobotic cases with North Bay General Hospital and over 35 telementoring cases with North Bay General Hospital, Ontario and the Complexe Hospitalier La Sagamie, Quebec. The network was eater extended to include more centers in Canada. While the FDA only permitted the single case of telesurgery of the Lindbergh operation in the USA, Canadian health authorities cleared the methodology for routine procedures.

Extreme Telesurgery

33

A remotely-controlled catheter guiding device guided by a robot was used in Milan in 2006 to automatically perform heart ablation, initiated and supervised by a group of professionals from Boston, MA. The robot uses high magnetic fields to direct the catheter to the desired location, taking advantage of the pre-operative CT scans of the patient and real time electromagnetic navigation. Initial trials were performed on 40 patients before the telesurgical experiment took place. The novelty of the system was that it could create the surgical plan on its own based on an anatomical atlas including 10,000 patients (Pappone et al., 2006). 4.1 Underwater trials NASA has conducted several experiments to examine the effect of latency on human performance in the case of telesurgery and telementoring. The NASA Extreme Environment Mission Operations (NEEMO) take place on the world’s only permanent undersea laboratory, Aquarius. It operates a few kilometers away from Key Largo in the Florida Keys National Marine Sanctuary, 19 meters below the sea surface. A special buoy provides connections for electricity, life support and communication, and a shore-based control center supports the habitat and the crew. Twelve NEEMO projects have been organized since 2001, and three were focusing on teleoperation recently. The 7th NEEMO project took place in October 2004. The mission objectives included a series of simulated medical procedures with an AESOP robot, using teleoperation and telementoring (Thirsk et al., 2007). The four crew members (one with surgical experience, one physician without significant experience and two aquanauts without any medical background) had to perform five test conditions: ultrasonic examination of abdominal organs and structures, ultrasonic-guided abscess drainage, repair of vascular injury, cystoscopy, renal stone removal and laparoscopic cholecystectomy. The AESOP was controlled from the CMAS (Ontario, Canada) 2,500 km away. A Multi-protocol Label Switching (MPLS) VPN was established, with a minimum bandwidth of 5 Mbps. The signal delay was tuned between 100 ms and 2 s to observe the effects of latency. High latency resulted in extreme degradation of performance: a single knot tying took 10 minutes to accomplish. The results showed that the non-trained crew members were also able to perform satisfyingly by exactly following the guidance of the skilled telementor. They even outperformed the non-surgeon physician, but fell behind the trained surgeon. Scientists also compared effectiveness of the telementoring and the quality of teleoperated robotic procedures. Even though the teleoperation got slightly higher grades, it took a lot more time to complete (Doarn et al., 2009). During the 9th NEEMO in April 2006 the crew had to assemble and install an M7 robot, and perform real-time abdominal surgery on a patient simulator. Throughout the procedure a microwave satellite connection was used, and time delay went up to 3 s to mimic the MoonEarth communication links. Each of the four astronauts had to train at least 2 hours with the wheeled in-vivo robots designed at the University of Nebraska. In another experiment, preestablished two-way telecom links were used for telementoring. The crew had to prove the effectiveness of telemedicine through the assessment and diagnosis of extremity injuries and surgical management of fractures. The effects of fatigue and different stressors on the human crew’s performance in extreme environments were also measured. Latency was set up to 750 ms in these experiments. The significant performance degradation of the microwave connection was noticed during stormy weather, causing a jitter in latency up to 1 s (Doarn et al., 2009).

34

Robot Surgery

Fig. 6. The Raven robot performing FLS tasks on board of NASA Aquarius in Florida, while guided by a surgeon from Seattle. (Photo: University of Washington) The 12th NEEMO project ran in May 2007, and one of its primary goals was to measure the feasibility of telesurgery with the Raven and the M7 robots (Figure 6). NASA sent a flight surgeon, two astronauts and a physician into the ocean. Suing operations were performed on a phantom in simulated zero gravity environment to measure the capabilities of surgeons controlling the robots from Seattle. This time the Aquarius was connected to the mainland through a Spectra 5.4 GHz Wireless Bridge, allowing for a minimum of 30 Mbps bandwidth, and average latency of 70 ms. The HaiVision CODEC was used for video compression giving very good quality, but also introduced significant latency, up to 1 sec. A group of three professionals guided the robot using commercial internet connection, and the communication lag time was increased till up to 1 s. Several simple tasks were performed, as part of the Fundamentals of Laparoscopic Surgery (FLS). The M7 demonstrated the first image-guided autonomous surgery (using a portable ultra sound system). It was live broadcasted at the American Telemedicine Conference 2007 (Nashville, TN). The M7 was able to insert the needle into a tissue phantom by itself. 4.2 Surgery in space To facilitate exploration missions beyond Earth, space agencies have always been pushing for more advanced telehealth concepts. Surgical experiments (laparotomy and celiotomy on rabbits) were first reported from Russian cosmonauts in 1967. The first survival procedure was performed on STS-90 Neurolab mission on rats in 1998 (Campbell el al., 2001). The world’s first human operation was a cyst removal from a patient’s arm, on board of the European Space Agency’s Airbus A-300 Zero-G aircraft. The plane performed 25 parabola curves, providing 20–25 s of weightlessness every time (New Scientist Space & AFP, 2006). ESA had plans to perform teleoperation in 2008 with a robot controlled through satellite connection, but the mission was postponed. NASA had its first zero gravity robotic surgery experiment in late September 2007 (Kamler, 2007). On a DC-9 hyperbolic aircraft suturing tasks were performed with the M7 (Figure 7). The performance of classical and teleoperated robotic knob tying was measured. Both the master and the slave devices were equipped with acceleration compensators, otherwise it would have been almost impossible to succeed

Extreme Telesurgery

35

with the tasks. The results showed that humans can still better adapt to extreme environments, however, advanced robotic solutions do not fall far behind.

Fig. 7. The M7 on board of a NASA parabolic flight, and the robot performing autonomous ultrasound-guided tissue biopsy. (Photo: NASA, SRI)

5. Challenges in teleoperation Effectiveness of surgical care heavily relies on the prompt delivery of treatment, and extreme teleoperation serves this principle. Beyond the obvious challenges of reduced medical equipment, constrained resources and probably limited experience of the on-site staff, several technical difficulties arise with extreme telesurgery. Significant delay in the sensor feedback can totally distract the surgeon and cause serious safety hazard, as examined by different research groups. Engineering methods have been developed to overcome the difficulties originating from the absence of communication infrastructure, unpredictable propagation condition changes and hardware failures. The U.S. Robotics roadmap points to robotic telesurgery as a major focus of research in order to improve quality of care (Christensen et al., 2009). It calls for engineering solutions to ensure natural interaction between the human operator and the remote robot through specific patient models, from whole-body level to tissue characteristics. This would allow for advanced off-site surgical planning, automated guidance and also for realistic training opportunity. 5.1 Effect of latency The primary difficulty with teleoperation over large distances or low quality network infrastructure is the communication lag time. The continuous development of the internet backbone infrastructure has resulted in a significant reduction of typical delays. Using commercial services, delay may be around 85 ms, across the United States, and lag time might be anywhere from 20-400 ms world-wide. Due to the Transmission Control Protocol (TCP/IP) and the routing algorithms latency can vary over trials, and this further degrades user performance. Satellite based internet connections can use a fleet of Low or Medium Earth Orbit (LEO/MEO) satellites such as the commercial constellations of Orbcom, Globalstar or Iridium. Typical roundtrip delays are 40 ms, but the bandwidth is only 64 kbps per channel. Currently developing O3b Networks (scheduled for deployment late 2010) would provide 1 Gbps with approximately 125 ms lag time. Geosynchronous satellites provide higher latency

36

Robot Surgery

due to their 36,000 km altitude above the equator. Round trip latency is 540-700 ms typically. Understandably, designated military satellites can provide a lot faster communication channel, the minimum latency per satellite hop is expected to be 4.3–7.8 ms one way (Berlocher, 2009). Despite the recent improvement in surface line speed, satellite communication has the potential to overcome ground lines primarily in speed, with a reasonable quality of service and availability. Beyond Earth orbit radio and microwave frequency signals propagate at almost the speed of light in space, however already in the range of long distance manned space missions, several minutes of latency can be experienced. Planet Mars orbits 56,000,000 km to 399,000,000 km from Earth which means a 6.5 to 44 minutes of delay in transmission. In addition, for about two weeks every synodic period, direct communication can be blocked, as the Sun stays in between Earth and Mars, direct. 5.2 Adaptation to latency Most humans are capable of adapting to sensory feedback latency up 500 ms (Anvari, 2004) and some experiments suggest that individuals might be able to perform tasks even with a consistent 1000 ms delay (Lum et al., 2008). Researchers showed that varying latency significantly reduces the operators’ performance both with robotic telesurgery and virtual reality (VR) applications (Thomson et al., 1999). It is advisable to use the consistent, maximum latency of system to achieve performance continuity. General approach to handle latency is to slow down the surgeons’ movements, allowing time for the visual feedback to confirm the intended move. However, in extreme cases this prevents the effective work and firm reaction to unexpected events. The on-site medical assistant can also help with imminent moves and minor tasks (Hanly et al., 2009). While keeping the stereo vision system’s two video channels synchronized is crucial for high quality performance, other modalities might be useful delivered earlier. By reflecting e.g. forces sooner back to the operator (bypassing the time video coding/decoding takes), they can improve their ability to compensate for latency. The compression and decompression of the video stream can be reduced by the use of novel CODECs and stateof–the-art computing hardware, but it still takes significant time, generally 100-700 ms. Approaching from the control theory point of view, several strategies have been developed to overcome the difficulties on the master side. One solution is to realize communication delays as force reflection for the human operator (Nohmi, 2003). It feels as if the remote manipulator was controlled through a virtually coupled spring, applying adequate forces. This method can be well used to provide information on the remote manipulator’s movement while there is no real feedback due to the latency, however it is not precise enough (and may alter the surgeons decisions by occasionally providing unreal forces) to approve it for surgical applications. When humans are adapting to asynchronous sensory feedback, they tend to create a virtual representation of the remote site to predict the consequences of their moves and project the tools ahead. A similar concept has been proposed for virtual reality based simulators (Frank, 1986). This has been successfully extended with sensory fusion for VR control (Kadavasal & Oliver, 2007), where the operator controls the model of the remote system in a virtual environment, and the lag time between the simulated and the real setup is handled by the environment model. We propose to apply this concept to telesurgery, where robot commands could be sent to a simulator that predicts the dynamic state of the virtual surgical site, including the robot’s position, and acceleration along with the patient’s body and tissue

Extreme Telesurgery

37

properties and reactions (Figure 8). The optimal control of the robot is calculated autonomously with high frequency on the patient site, while the Intelligent Surgical Interpreter provides an interface to the master controller. Sensory updates are processed by the simulators at the surgeon site, and the virtual environment is updated according to the new measurements. This framework allows the smooth integration of different modalities, but require a very precise 3D model of the patient, gained from pre-operative MRI, CT and PET scanning. The models might be continuously updated through intra-operative imaging techniques. A variety of operations and possible outcomes could be simulated and analyzed before the actual surgery takes place, reducing the risk of complications.

Fig. 8. The concept of virtual reality extended control of surgical robots in order to locally deal with the disturbing effects of latency. 5.3 Communication protocol Further difficulties may arise with the data protocol of the robots that links the master consol and the slave arms. Presently, the majority of telepresence systems communicate through Transmission Control Protocol (TCP) that is used along with the Internet Protocol (IP) to send data in the form of individual units–packets. Another common type is the User Datagram Protocol (UDP), a connectionless protocol that—like the TCP—runs on top of IP networks. UDP/IP provides very few error recovery services, offering instead a direct way to send and receive datagrams. Asynchronous Transfer Mode (ATM/AAL1), which encodes data traffic into small fixed sized packets is also frequently used, but lacks advanced security services, just as the UDP/IP. In the case of communication breakdown, the recovery time may be critical, therefore redesigned gateway architecture should be added to allow TCP transfers to survive a long duration blockage. The Zeus and the da Vinci were designed to discard each packet that has any sort of internal error; they do not correct bit-level errors. If several packets are lost, or there is a breakdown, the robots suspend their operation. To meet the special communication requirements

38

Robot Surgery

through satellites, the Space Communications Protocol Standards (SCPS) was developed and tested by DoD and NASA (Wang & Horan, 2009). SCPS uses similar architecture to TCP/IP, but it is more effective in handling latency created by long distance transmissions and the noise associated with wireless links. The SCPS exists as a full ISO standard, and also meets the U.S. Military Standards. To ensure superior quality visual and tactile feedback, high sampling rate must be used on the patient site (app. 1 ms). Along with the high definition video feedback this has a significant bandwidth demand. Under regular circumstances a 10 Mbps connection is already suitable for teleoperation, however in the case of high definition, multimodal equipment, a 40 Mbps two-channel link would be required (Spearing & Regan, 2005). This may not cause much problem on the International Space Station (ISS) that was equipped with a 150 Mbps connection in 2005, but in the case of a Mars mission, NASA only plans to develop a 5 Mbps connection as a part of the new space communication architecture relying on the reconfigurable Space Telecommunications Radio System (STRS), and upgrade it to 20 Mbps by 2020 (Reinhart & Johnson, 2008).

6. Long duration space mission support While advanced internet based communication networks enables effective telesurgery all over the Earth (with the discomfort of latency), serious technological problems arise in the case of long-haul space exploration missions. Space medicine and health care have always been a critical issue for aerospace agencies and several comprehensive studies reckon with the technological capabilities and challenges (Campbell & Billica, 2008). Despite the current financial difficulties, the overall goal and future direction in exploration is towards the continuous human presence on the Moon and on Mars. The previously proposed MARS mission by NASA would have required the support of a 6 member crew for 18 months. The team’s designed healthcare module is a subsystem within the prefabricated habitat providing 15.9 m2 space, and 2,500 kg payload (Drake, 2009). The presently used communication systems have serious limitations concerning the achievable minimum communication lag time, maximum bandwidth and robustness. Based on recent experiments illustrated above, we have a better understanding of the effects and drawbacks of extreme long distance telesmedicine that also apply for telementoring. As long as a new level of machine automation is not reached, it seems inevitable to have a flight surgeon on board of the spacecraft, to adapt to any unforeseeable event. Flight surgeons should receive special training for a better command over computer integrated surgical technology to be provided on board. The rest of the crew should also undergo comprehensive medical training to attain the skills required to monitor any surgical procedure, and to interact in the case of immediate danger. It is also important to practice the skills with the surgery robot throughout the mission, even if no accident occurs. Based on the pre-described conditions, difficulties and system requirements, a three-layered mission architecture is proposed to achieve the highest degree of performance possible, by combining robotic and human surgery (Figure 9). Depending on the physical distance between the space ship and the ground control centre, different telepresence technologies may end up with the best result. Basically, with the accession of the latency, real-time control strategies and communication techniques’ effectiveness decreases significantly. By adaptively switching, different levels of surgical service can be provided throughout the mission.

Extreme Telesurgery

39

Fig. 9. Concept of telehealth support to provide maximum level of available medical care to astronauts during long distance exploration missions. Mainly within the range of 380,000 km (app. the Earth-Moon average distance), regular telesurgery techniques can be used in space to provide medical support in the case of emergency. Leaving the Earth orbit, special control strategies have to be applied, to extend the feasibility of telesurgery up to a maximum of 2 s of delay. With robot assisted surgery, a shared control approach should be followed, integrating high-fidelity automated functions into the robot, to extend the capabilities of the human surgeon. For example, to automatically follow the movements of the organs (the beating heart and breathing lung), the robots should be equipped with adequate visual and force sensors, and the precise control algorithms have to be built in on the slave side. Assuming the minimum expertise of the crew to be equivalent of Emergency Medical Technician in these missions, telepresence systems should only rely on assistance and support from the crew. Successful methods have been developed recently to provide automatic movement compensation (Ortmaier et al., 2006). This concept could be most beneficial for long duration on-orbit missions, primarily on board of the ISS. Presently, there is no other option than the immediate evacuation of the affected astronaut, which poses bigger health risk and huge costs. Flying further from the Earth and having reached the limits of pseudo real-time communication, the procedures should be performed by the flight surgeon, or by any other trained astronaut, under the telementoring guidance of the master surgeons on the ground. Telementoring requires exchange of still images, motion video, digital image editing, voice conferencing, electronic chat and data file transfer. As showed by the NASA undersea experiments (Thirsk et al, 2007), telementoring can be an effective alternative to direct teleoperation, allowing the controller to perform the tasks based on the visual and voice

40

Robot Surgery

commands of the ground centre. With adequate training and practice, the astronauts with a basic surgical training should be able to successfully accomplish complete procedures. As tested on USS Abraham Lincoln carrier in 1998, 9.6 28.8 kbps connection can already be enough to transfer images at 2-4 fps speed (Cubano et al. 1999). Telementoring may extend the boundaries of telepresence, as it can still be effective with a 50-70 s delay (within the range of app. 10,000,000 km). Upon this phase, the built-in semi-automatic functions of the surgical robot may have a significant role to improve the overall quality of the surgery. Motion scaling, adaptive tremor filtering, the automated following of the organ’s movement, automated suturing could significantly improve the less practiced crew members’ performance on one hand, while special security measures could also be applied. On the other hand, the setting of virtual boundaries for the robot, tool limitations and speed constraints may reduce the risk of accidents. Astronauts should also benefit from advanced imaging technologies (e.g.: accurately matched anatomic atlases for better navigation around the organs.) With the use of augmented reality systems, live and virtual images can be merged in real time to make the operation even smoother. Surgical malpractice can be reduced significantly by applying safe zones (virtual fixtures) that allow the robot to operate only within the predefined area (Lin et al., 2006). The safeguard teleoperation concept developed originally for mobile space robots could be useful in surgery. The robot can autonomously perform the routine tasks with the real time supervision of a human, however in the case of any malfunction or sudden events, the human operator can take over the control. There is no crisp boundary between the application of telementoring and consultancy telemedicine. Above a certain signal delay, the terrestrial medical support crew will not be able to react in time to unforeseeable events during the procedure; the flight surgeon will be left alone for longer and longer periods. Above around one minute of delay, it is inconvenient and impractical for the crew to wait for the guidance of the ground after every step, and in some cases, it would endanger the success of the operation. For these missions, the physician must be trained to conduct the operation and make decisions on its own. It was shown during the NEEMO missions that the general performance of telesurgery is higher than of the telemedicine, and a team of experts may do better than flight surgeons. Therefore depending on the feasibility, telesurgery should be preferred over telementoring. With a complete remote controlled robot on board of a vessel, high quality surgical assistance could be provided for long duration space missions. Besides, the astronauts would be able to conduct several material and life science experiments and research, using the robots for micro-manipulations, and assist post-operative interventions. Advanced system design will help to deal with signal delays and to extend human capabilities.

7. Conclusion In the case of telepresence surgery, intercontinental procedures, space missions and other highly complex exploration tasks and telehealth may mean the only sustainable solution to provide complete medical support. Telemedicine gains increasing importance as technology provides new and more effective means of telepresence to gain access to distant places. Medical robotic systems are already able to widely extend the human surgeons’ capabilities, to provide high fidelity support for a great variety of procedures. The new generation of robots will lead to a breakthrough in general healthcare.

Extreme Telesurgery

41

Extensive effort has been put into the exploration of this new domain of telemedicine, as reviewed in this chapter. To meet the special requirements, completely new and innovative structures are built for long distance telesurgery. The most extreme example of teleoperation is in space applications. Long duration missions and venturing beyond Earth orbit mean new technological challenges, especially considering life-support systems. By integrating cutting-edge mechatronic equipment, semi-autonomous robots could ensure the medical support for a 2-3-year-long mission through telehealth technology. With the combination of real-time teleoperation, telementoring and consultancy telemedicine, the overall mission safety can be greatly increased, assuming a limited level of autonomy to improve the usability. The next few years of research will lead to breakthroughs in the interdisciplinary field of Computer-Integrated Surgery, opening further opportunities for telesurgical application. Robots and smart tools controlled through communication networks are soon to answer the special needs of remote patients.

8. Acknowledgment The research was supported by the National Office for Research and Technology (NKTH), Hungarian National Scientific Research Foundation grants OTKA T69055, CK80316.

9. References Alexander, A.D. (1973). Impacts of Telemation on Modern Society, Proc. of Human Factors and Ergonomics Society Annual Meeting, Vol., 17, No., 2, 1973 , pp.299-304 Anvari, M. (2004). Robot-Assisted Remote Telepresence Surgery, Surgical Innovation, Vol.,11, No., 2, pp.123-128 Ballantyne, G.H.; J. Marescaux & P. C. Giulianotti (eds.) (2004). Primer of Robotic & Telerobotic Surgery, Lippincott Williams & Wilkins, 2004, ISBN 0-7817-4844-5 Ballantyne, G.H. (2007). The Future of Telerobotic Surgery, Chapter 18 in Patel, V.R. (editor), Robotic Urologic Surgery, 2007, pp.199-206, ISBN: 978-1-84628-545-5 Berlocher, G. (2009). Minimizing Latency in Satellite Networks, Via Satellite, Published at: www.viasatellite.com, September 2009, Accessed: September 2009 Bowersox, J.C.; Shah, A.; Jensen, J.; Hill, J.M.; Cordts, P.R. & Green, P.S. (1996). Vascular applications of telepresence Initial feasibility studies in swine surgery, Journal of Vascular Surgery, Vol., 23, Issue 2, February 1996, pp.281-287 Campbell, M.R.; Kirkpatrick, A.W; Billica, R.D.; Johnston, S.L.; Jennings, R.; Short, D.; Hamilton, D. & Dulchavsky, S.A. (2001). Endoscopic surgery in weightlessness: The investigation of basic principles for surgery in space, Journal of Surgical Endoscopy, Vol., 15, pp.1413–1418 Campbell, M.R. & Billica, R.D. (2008). Surgical Capabilities, Chapter 6 in Barratt, M.R.; Pool, S.L. (eds.), Principles of Clinical Medicine for Space Flight, Springer, 2008, ISBN: 978-0387-98842-9 Christensen, H.I. et al. (2009). A Roadmap for US Robotics: From Internet to Robotics, Available online: http://www.us-robotics.us/reports/CCC%20Report.pdf Accessed: September, 2009 Cubano, M., Poulose, B.K., Talamini, M.A., Stewart, R., Antosek, L.E., Lentz, R., Nibe, R., Kutka, M.F. & Mendoza-Sagaon, M. (1999). Long distance telementoring: A novel

42

Robot Surgery

tool for laparoscopy aboard the USS Abraham Lincoln, Surgical Endoscopy, Vol., 13., No., 7., 1999, pp.673-678, ISSN 0930-2794 Das, H.; Ohm T.; Boswell, C.; Steele, R. & Rodriguez, G. (1998). Robot Assisted MicroSurgery Development at JPL; Technical Report, NASA JPL, Pasadena Doarn, C.R.; Anvari, M.; Low, T. & Broderick, T.J. (2009). Evaluation of Teleoperated Surgical Robots in an Enclosed Undersea Environment, Journal of Telemedicine and eHealth, Vol., 15 No., 4, May 2009, pp.325-335 Drake, B.G. (editor) (2009). Human Exploration of Mars Design Reference Architecture 5.0, Mars Architecture Steering Group, NASA HQ, July 2009, NASA/SP–2009–566 Eirik, L.; Johansen, B.; Gjelsvik, T. & Langø T. (2009). Ultrasound based localisation of wireless microrobotic endoscopic capsule for the GI tract, Proc. 21st Conference of the Society for Medical Innovation and Technology (SMIT2009), Sinaia, Romania Fabrizio, M.D.; Lee, B.R.; Chan, D.Y.; Stoianovici, D.; Jarrett, T.W.; Yang, C. & Kavoussi, L.R. (2000). Effect of time delay on surgical performance during telesurgical manipulation, Journal of Endourology, Vol. 14, No. 2, March 2000 Flynn, E. (2005). Telesurgery in the United States, Homeland Defense J., June 2005, pp.24-28 Frank, L.H., (1986). Effects of visual display and motion system delays on operator performance and uneasiness in a driving simulator, PhD Thesis, Virginia Polytechnic Institute and State University, 1986 Green, P.E.; Piantanida, T.A.; Hill, J.W.; Simon, I.B. & Satava, R.M. (1991). Telepresence: dexterous procedures in a virtual operating field (Abstr), American Journal of Surgery, Issue 57, 1991, pp.192 Hager, G.D.; Okamura, A.M.; Kazanzides, P.; Whitcomb, L.; Fichtinger, G.; Taylor, R. (2008). Surgical and Interventional Robotics Part III; IEEE Robotics & Automation Magazine, Vol., 15, Issue 4, December 2008, pp. 84-94 Hagn, U., Nickl, M.; Jorg, S.; Passig, G.; Bahls, T.; Nothhelfer, A.; Hacker, F.; Le-Tien, L.; Albu-Schaffer, A.; Konietschke, R.; Grebenstein, M.; Warpup, R.; Haslinger, R.; Frommberger, M. & Hirzinger, G. (2008). The DLR MIRO: a versatile lightweight robot for surgical applications, International Journal of Industrial Robot, Vol., 35 No., 4, pp.324–336 Hanly, E.J. & Broderick, T.J. (2005). Telerobotic Surgery, Operative Techniques in General Surgery, Vol., 7, Issue 4, December 2005, pp.170-181 Herman, B.C. (2005). On the Role of Three Dimensional Visualization for Surgical Applications in Interactive Human Machine Systems, Master thesis, Computer Science, The Johns Hopkins University, May 2005 Kadavasal, M.S. & Oliver, J.H. (2007). Sensor Enhanced Virtual Reality Teleoperation in Dynamic Environment, Proc. of IEEE Virtual Reality Conference (VR’07), pp.297-298, Charlotte, NC Kamler, K. (2007). How I Survived a Zero-G Robot Operating Room: Extreme Surgeon; Popular Mechanics—online edition, November 2007 Kumar, S. & Marescaux, J. (eds.) (2008). Telesurgery, Springer, 2008, ISBN 978-3-540-72998-3 Lee, B.R.; Caddedu, J.A.; Janetschek, G.; Schulam, P.; Docimo, S.G.; Moore, R.G.; Partin, A.W. & Kavoussi, L.R. (1998). International surgical telementoring: our initial experience, Studies in health technology and informatics, Issue 50, 1998, pp.41-47 Lin, H.C.; Marayong, P.; Mills, K.; Karam, R.; Kazanzides, P.; Okamura, A. & Hager, G.D. (2006). Portability and Applicability of Virtual Fixtures Across Medical and

Extreme Telesurgery

43

Manufacturing Tasks. Proc. of the 2006 IEEE International Conference on Robotics and Automation, pp. 225-330, Orlando, FL Lum, M.J.H.; Rosen, J.; Lendvay, T.S.; Wright, A.S.; Sinanan, M.N. & Hannaford, B. (2008). TeleRobotic Fundamentals of Laparoscopic Surgery (FLS): Effects of Time Delay Pilot Study, Proc. of 30th Annual International IEEE EMBS Conference Vancouver, Canada, August 2008 Lum, M.J.H.; Friedman, D.C.W.; Sankaranarayanan, G.; King, H.; Fodero, K.; Leuschke, R.; Hannaford, B.; Rosen, J. & Sinanan, M.N. (2009). The RAVEN: Design and Validation of a Telesurgery System, International Journal of Robotics Research, Vol., 28; No., 9, pp.1183-1197 Marescaux, J.; Leroy, J.; Rubino, F.; Vix, M.; Simone, M. &. Mutter, D. (2002). Transcontinental Robot-Assisted Remote Telesurgery: Feasibility and Potential Applications; Annals of Surgery, Vol. 235, No. 4., pp.487-492 Menciassi, A. & Dario, P. (2009). Miniaturized Robotic Devices for Endoluminal Diagnosis and Surgery: A Single-Module and a Multiple-Module Approach, Proc. of the 31st Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBS), Minneapolis, MN, August 2009 MeRoDa (2009). Medical Robotics Database, http://www.ma.uni-heidelberg.de/apps/ /ortho/meroda/ Accessed: September 2009 Nathoo, N.; Cavusoglu, M.C.; Vogelbaum, M.A. & Barnett, G.H. (2005). In Touch with Robotics: Neurosurgery for the Future, Journal of Neurosurgery, Vol., 56. No., 3., March 2005, pp.421-433, ISSN 1524-4040 New Scientist Space & AFP (2006). Doctors remove tumor in first zero-g surgery; New Scientist, 27. September, 2006 Nohmi, M. (2003). Space Teleoperation Using Force Reflection of Communication Time Delay; Proc. of IEEE/RSJ Intl. Conf. on Intelligent Robots and Systems, Las Vegas, NV Ortomaier, T.; Groger, M.; Boehm, D.H.; Falk, V. & Hirzinger, G. (2006). Motion Estimation in Beating Heart Surgery; IEEE Trans. on Biomedical Engineering, Vol. 52., No. 10., October 2005, pp. 1729-1740, ISSN: 0018-9294 Pappone, C.; Vicedomini, G.; Manguso, F.; Gugliotta, F.; Mazzone, P.; Gulletta, S.; Sora, N.; Sala, S.; Marzi, A.; Augello, A.; Livolsi, L.; Santagostino, A. & Santinelli, V. (2006). Robotic Magnetic Navigation for Atrial Fibrillation Ablation, Journal of the American College of Cardiology, Vol., 47, No., 7, 2006, ISSN 0735-1097 Reinhart, R.C. & Johnson, S.K. (2008). SDR/STRS Flight Experiment and the Role of SDRBased Communication and Navigation Systems Communications Division, IDGA 6th Annual Software Radio Summit, Vienna, VA, February 2008 Rentschler, M.; Dumpert, J.; Platt, S.; Oleynikov, D.; Farritor, S. & Iagnemma, K. (2006). Mobile In Vivo Biopsy Robot, Proc. of the 2006 IEEE International Conference on Robotics and Automation, pp. 4155-4160, Orlando, FL Rosen, J. & Hannaford, B. (2006). Doc at a distance, IEEE Spectrum Magazine, Vol. 8., No. 10., October 2006, pp.34-39 Rosser Jr., J.C.; Wood, M.; Payne, J.H.; Fullum, T.M.; Lisehora G.B.; Rosser, L.E.; Barcia, P.J. & Savalgi, R.S. (1997). Telementoring. A practical option in surgical training, Surgical Endoscopy, Vol., 11., No., 8., August 1997, pp.852–855, ISSN 0930-2794

44

Robot Surgery

Rosser Jr., J.C.; Young, S.M. & Klonsky, J. (2007). Telementoring: an application whose time has come, Surgical Endoscopy, Vol., 21., No., 8., August 2007, pp.1458–1463, ISSN 0930-2794 Satava, R.M. (1995). Virtual reality, telesurgery, and the new world order of medicine. Journal of Image Guided Surgery, Issue 1, 1995, pp.12–16 Schenker, P.S.; Das, H. & Ohm, T.R. (1995). A New Robot for High Dexterity Microsurgery, Proc. of the First International Conference on Computer Vision, Virtual Reality and Robotics in Medicine, Springer Lecture Notes In Computer Science (LNCS), Vol., 90, 1995, pp.115-122, ISBN:3-540-59120-6 Spearing, R. & Regan, M. (2005). 4.0 NASA Communication and Navigation Capability Roadmap, Executive Summary, 2005 Thirsk, R.; Williams, D. & Anvari, M. (2007). NEEMO 7 undersea mission, Acta Astronautica, Vol. 60., Issue 4-7, February – April 2007, pp.512-517 Thomson, J.M.; Ottensmeyer, M.P & Sheridan, T.B. (1999). Human Factors in Telesurgery: Effects of Time Delay and Asynchrony in Video and Control Feedback with Local Manipulative Assistance, Telemedicine journal, Vol., 5, No., 2, pp.129-137 Trauma Pod (2009). http://www.darpa.mil/dso/thrusts/bio/tactbio_med/traumapod/ /index.htm Accessed: September, 2009 Wang, R. & Horan, S. (2009). Protocol Testing of SCPS-TP over NASA's ACTS Asymmetric Links, IEEE Transactions on Aerospace and Electronic Systems, Vol., 45, Issue 2, April 2009, pp.790-798, ISSN: 0018-9251

3 Telementoring and Telesurgery: Future or Fiction? Vitor da Silva, Tom McGregor, Reiza Rayman, Patrick PW Luke

CSTAR, Department of Surgery and Biomedical Physics The University of Western Ontario, Schulich School of Medicine London, Ontario, Canada

1. Introduction Over the last two decades, minimally invasive surgery (MIS) has emerged as an attractive alternative to traditional open surgical procedures. MIS has been shown to provide excellent surgical outcomes with the added benefit of decreased procedure-related morbidity. Minimal bleeding, reduced blood transfusion rates, shorter hospitalization, and shorter recovery times are all proven advantages for laparoscopic procedures. [1-3] However, many MIS procedures are more technically challenging than the traditional open counterpart, and the learning curve to proficiency is markedly steeper than standard open procedures. Several factors including establishing adequate access, two dimensional vision, decreased depth perception, restricted instrument maneuverability, decreased dexterity and dampened tactile feedback are all unique limitations that make laparoscopic surgery challenging for surgeons trained in traditional open approaches. To the laparoscopically naïve surgeon, this translates into a loss of confidence in performing a procedure in which they were previously skilled. Appropriate training and education are therefore essential for a surgeon to develop the necessary skills required in order to comfortably perform a surgery adequately and safely. Unfortunately, resources are limited. Time, monetary and geographical constraints often limit the ubiquitous dissemination of new surgical knowledge, skills and techniques. The inability to provide adequate training opportunities and support for surgeons in the community continues to be the limiting factors determining the success and widespread availability of laparoscopic surgeries. Thankfully, with the ever-increasing push to incorporate technological advances into the medical field, we are now able to overcome these barriers. In this chapter we outline how the recent progress in technology and telecommunication has led to the advent of telemedicine – an ingenious solution to our current problem, which will allow for the widespread availability of MIS and improve patient care.

2. What is telemedicine? Defined as “medical care at a distance”, telemedicine is a broad term referring to a physician’s ability to practice medicine and directly influence patient care without being physically at the bedside. The underlying principle of telemedicine involves advanced

46

Robot Surgery

telecommunication systems for data acquisition, processing and display allowing the physician or health care worker to transfer their expertise from a remote location. This opens the door for a wealth of applications, transcending geographical barriers when participating in patient care. Of particular interest to our discussion are the two main branches of telemedicine for surgeons – telementoring and telesurgery.

3. Telementoring As cutting edge technology evolves, new surgical techniques are developed. This has occurred with the development of laparoscopy, laser, and robotic surgery. Surgeons already established in their community or academic practices have limited time to re-train or take sabbaticals to learn new skills necessary to carry out novel complex operative procedures. In part, this may have contributed to prolonged operative times and alarmingly high complication rates associated with the early development in laparoscopic radical prostatectomy (LRP) [4]. In general, the ability to efficiently train a surgeon to become facile at LRP has requires fellowship training, or recruitment of an experienced surgical mentor. However, when local expertise is not available, it is a challenge to recruit a mentor to teach novel operative techniques, as there rarely exists an established remunerative or academic reward to lure the mentors away from their regular patient-care and academic activities in order to travel and teach others. Therefore, telementoring has been developed to allow longdistance training utilizing mentors from a different hospital, city or continent. Telementoring involves procedural guidance of one professional by another from a distance using telecommunications. This has involved interactions involving audio dialogue, video telestration (video tablet and pen), and even guidance of a camera or laparoscope with a surgical robot such as AesopTM (Computer Motion, Santa Barbara, CA). In order to send audiovisual data, connections using WAN (wide area network), LAN (local area network), integrated services digital network (ISDN) or internet protocol (IP) links have been utilized. Security has been established through virtual private networks (VPNe) to prevent others to access and manipulate connections. At first, telementoring was developed by surgeons from the Johns Hopkins University group utilizing rudimentary teleconferencing audiovisual equipment and a video sketch pad to provide telestration (Cody Sketchpad, Chryon Corp., Melville, NY). Trainees were provided mentorship from the staff surgeons situated 1000 feet away [5]. This developed into telementoring studies involving the USS Abraham Lincoln Aircraft Carrier Battle Group. Five laparoscopic inguinal hernia repairs were performed under telementored guidance from land-based surgeons from Maryland and California [6]. This established the ability to perform long-distance telementoring across bodies of water in times of war. Furthermore, Kavoussi’s group utilized the AesopTM robot as well as the Socrates telestration system (Intuitive Surgical) to telementor 17 urologic operations (including laparoscopic nephrectomy) between Baltimore, Maryland to Rome, Italy. However, the procedures were associated with a half second image delay between sites, and a high technical failure rate (5/17) due to an inability to establish connections through their 4 ISDN lines during times of heavy traffic [7;8]. In its early development, most of the procedures utilizing telementoring have required that an experienced surgeon was situated at the patient’s operative tableside. Accordingly, in March 2003, our group from London, Ontario, Canada harnessed SOCRATESTM and AESOPTM telerobotic technology through 4 ISDN lines to successfully telementor

Telementoring and Telesurgery: Future or Fiction?

47

laparoscopic nephrectomy and pyeloplasty with the mentor situated over 200 km away. Since our intent was to test the ISDN connections and the robotic platforms, we ensured that the bedside surgeon was equally as experienced as the mentor, and could complete the operation in case of communicative technical failure. Subsequently, our group has prospectively tested telementoring in a ‘real-world’ situation, with a truly ‘inexperienced’ trainee with a ‘complex’ new procedure. As we have stated in the past, LRP is one of the most technically challenging operations in urology, with a steep learning curve associated with prolonged operative times, complications and poor oncologic outcomes during the early development of the procedure [4]. It has been stated that surgeons need to complete 50-300 cases in order to obtain operative proficiency for LRP. For the first time, we described the experience utilizing long-distance telementoring to facilitate the performance of the LRP with a trainee surgeon naïve to LRP. It should be mentioned, however, that although the trainee had never performed LRP, he had a high volume laparoscopic surgical practice. Utilizing an ISDN telecommunications network, the LRPnaïve trainee observed 6 LRP performed by a trainer located 200 km away from Hamilton to London Ontario (group1) (Figure 1). Using the same network, the trainee performed 6 LRP under the supervision of the remote trainer (group 2). The next six LRP procedures were performed by the trainee independently (group 3). The trainer and trainee were able to communicate back and forth using audio equipment and visual demonstration of anatomy and techniques were communicated via a pen and tablet video screen. The audiovisual feeds were facilitated by simple Polycom technology and ISDN lines. Due to weather issues, telecommunications failed in 1 case. Audiovisual communication was excellent and although visual delays were experienced, this did not greatly impact upon the success of the cases. The median operative times for the three groups were 200 min, 285 min vs. 250 min respectively (p = NS between groups 2 and 3). Median blood loss was not different between groups and no blood transfusions were performed. No anastomotic leaks, open conversion or intraoperative complications occurred. Of the patients with confined disease (pT2), only one patient had a local positive surgical margin (group 2) with all patients having undetectable disease at 1 year. At the 1 year follow-up mark, 11/12 patients in group 2 and 3 have achieved complete urinary continence. Of 8 patients in the groups 2 and 3 that underwent bilateral nerve sparing, 38% of patients achieved potency by 12 months. It was concluded that telementoring could be performed to teach complex operative procedures such as LRP to surgeons. Similarly, Schlacta’s group from our centre had successfully trained less-experienced community-based general surgeons (through direct local and telementoring) to perform laparoscopic colon surgery. Although 33% of cases were converted to standard open procedures, the group concluded that there was excellent incorporation of laparoscopic colon surgery into this community-based practice [9]. We conclude that performance of telementoring is feasible and that it is possible to teach complex operations with current technology. We also believe that telementoring does not need to be limited to MIS procedures. Although the majority of hospital administrators are facile with teleconferencing, and telemedicine has been explored by a number of physician groups for patient care and education, surgeons have been slow to adapt to the same technology. We have shown that telementoring using ISDN lines is feasible and relatively inexpensive, utilizing existing communication lines. However, its eventual adaptation in healthcare will depend on further education and an evolution in surgical thinking.

48

Robot Surgery

Fig. 1. Telementoring set-up. The set up in our telementoring procedures involved 4 ISDN lines as well as audiovisual Polycoms, and video screen telestrator. The AESOP laparoscope holding robot was used during early, but not later clinical use. The mentor is pictured on the left while the trainee along-side the OR table is pictured on the right hand side.

4. Telesurgery Telesurgery involves a surgical procedure with the surgeon being situated remotely from the patient. The history of telesurgery dates back to the first commercial application in laparoscopy. The Automated Endoscopic System for Optimal Positioning (AESOPTM) was FDA approved in the United States in 1993 and was used solely to guide the laparoscope. When it was initially introduced, the surgeon controlled the robotic arm either manually or remotely with hand or foot switches. Later versions were modified and equipped with voice controls. Although the use of has been associated with ‘telementoring procedures’, its development gave way to the complex three armed robotic technology that integrated instrument manipulating arms as well. The manufacturer of the AESOPTM, Computer Motion Inc., would later introduce the three armed ZEUSTM robotic system onto the U.S. market in 1998. Concurrently, Intuitive Surgical (Sunnyvale, California) released yet another 3-arm surgical robot, the da Vinci®. Developed from technology designed by NASA, the da Vinci® was originally intended for use by the U.S military, but was quickly adopted for civilian use. In 2003, a merger between Computer Motion Inc. and Intuitive surgical paved the way for the da Vinci® robot, along with it’s newly FDA approved EndoWristTM technology, to dominate the surgical robot market worldwide. The large majority of published literature on robotic-assisted surgery to date, has employed the use of the da Vinci® system. Currently, it is the only commercially available surgical robotic system. The da Vinci® consists of separate components. The surgeon sits at the console where he/she is able to visualize the surgical field in 3D and operate several hand and foot controls. The surgeon’s motions are processed by a computer system and relayed to the

Telementoring and Telesurgery: Future or Fiction?

49

robotic arms. The robot has three arms. The central arm holds the camera and 2-3 outer arms hold the surgical instruments, which articulate at the EndoWristTM. This allows the instruments to move with seven degrees of freedom and two degrees of axial rotation, eliminating many of the difficulties associated with standard laparoscopic procedures. Initially, commercial surgical robots were intended to perform minimally invasive cardiac procedures. However, since the initial description for robot assisted closed-chest coronary artery bypass grafting at our centre in 1999 [10], applications for robotic surgery have been rapidly growing. Since its inception, robotic surgery has not only expanded to other cardiac surgical procedures such as left internal mammary artery take-down and mitral valve repair, but also several gastrointestinal, gynecological and urological procedures. These included: cholecystectomy, Nissen fundoplication, Heller myotomy, pancreatectomy, hepaticojejunostomy, gastric banding, distal gastrectomy, Roux-en-Y gastric bypass, colectomy, tubal re-anastamosis, hysterectomy, nephrectomy, pyeloplasty, adrenalectomy, aneurysm repair and radical prostatectomy, among others. Due to the increased precision and dexterity that the robot contributes to the case, the robot has been exploited for radical prostatectomy more than any other procedure, since it has allowed laparoscopically naïve surgeons to perform laparoscopic suturing to perform critical anastomotic maneuvers with relative ease. We have shown that the robot improves the performance of experienced laparoscopic surgeons as well [11]. Of relevance to telesurgery, these robotic platforms were designed using connections that permitted surgery to be performed with the surgeon at a console remote from the bedside robot and patient. In fact, the original intent was to permit the surgeon to perform surgery just as easily in another room, another building, another continent, or in outer space. Indeed, any surgical procedure with the surgeon sitting remotely from the patient could be considered remote telesurgery. However, it is the possibility of performing long-distance telesurgery that stirs the imagination. Most notably, in 2001, Marescaux et al. revolutionized surgery by performing a transAtlantic robotic assisted cholecystectomy using the ZEUSTM robot [12]. The surgeon and console were located in New York, and the patient and effector arms were in Strausbourg, France. Asynchronous transfer mode (ATM) technology was used to establish connections via high-speed terrestrial fiberoptic networks with a bandwidth of 10Mb/s. These connections were reserved exclusively for the procedure that ran a round-trip distance of 14000 km. Although there was a lag time of 155 ms, the laparoscopic cholecystectomy was completed without incident over 54 minutes. It should be noted that although audiovisual interactions and robotic arm movements were performed through the trans-Atlantic connections, the application of ‘electrocautery’ to dissect the gall bladder, placement of clips, introduction of the ports, and closure of port-sites had to be performed by the bed-side assistants. As well, laparoscopic cholecystectomy is a relatively simple laparoscopic procedure and could have been easily completed by the bed side surgeons with greater ease and in less time. Although the cost of this solitary operation was astronomical, it demonstrated that ‘real world’ long-distance telesurgery was feasible, and if the lag time could be limited to