Modeling, Analysis, Force Sensing and Control of Continuum Robots for Minimally Invasive Surgery

This dissertation describes design, modeling and application of continuum robotics for surgical applications, specifically parallel continuum robots (PCRs) and concentric tube manipulators (CTMs). The introduction of robotics into surgical applications has allowed for a greater degree of precision, less invasive access to more remote surgical sites, and user-intuitive interfaces with enhanced vision systems. The most recent developments have been in the space of continuum robots, whose exible structure create an inherent safety factor when in contact with fragile tissues. The design challenges that exist involve balancing size and strength of the manipulators, controlling the manipulators over long transmission pathways, and incorporating force sensing and feedback from the manipulators to the user. Contributions presented in this work include: (1) prototyping, design, force sensing, and force control investigations of PCRs, and (2) prototyping of a concentric tube manipulator for use in a standard colonoscope. A general kinetostatic model is presented for PCRs along with identification of multiple physical constraints encountered in design and construction. Design considerations and manipulator capabilities are examined in the form of matrix metrics and ellipsoid representations. Finally, force sensing and control are explored and experimental results are provided showing the accuracy of force estimates based on actuation force measurements and control capabilities. An overview of the design requirements, manipulator construction, analysis and experimental results are provided for a CTM used as a tool manipulator in a traditional colonoscope. Currently, tools used in colonoscopic procedures are straight and exit the front of the scope with 1 DOF of operation (jaws of a grasper, tightening of a loop, etc.). This research shows that with a CTM deployed, the dexterity of these tools can be increased dramatically, increasing accuracy of tool operation, ease of use and safety of the overall procedure. The prototype investigated in this work allows for multiple tools to be used during a single procedure. Experimental results show the feasibility and advantages of the newly-designed manipulators

Novel application of simultaneous multi-image display during complex robotic abdominal procedures

BACKGROUND: The surgical robot offers the potential to integrate multiple views into the surgical console screen, and for the assistant's monitors to provide real-time views of both fields of operation. This function has the potential to increase patient safety and surgical efficiency during an operation. Herein, we present a novel application of the multi-image display system for simultaneous visualization of endoscopic views during various complex robotic gastrointestinal operations. All operations were performed using the da Vinci Surgical System (Intuitive Surgical, Sunnyvale, CA, USA) with the assistance of Tilepro, multi-input display software, during employment of the intraoperative scopes. Three robotic operations, left hepatectomy with intraoperative common bile duct exploration, low anterior resection, and radical distal subtotal gastrectomy with intracorporeal gastrojejunostomy, were performed by three different surgeons at a tertiary academic medical center. RESULTS: The three complex robotic abdominal operations were successfully completed without difficulty or intraoperative complications. The use of the Tilepro to simultaneously visualize the images from the colonoscope, gastroscope, and choledochoscope made it possible to perform additional intraoperative endoscopic procedures without extra monitors or interference with the operations. CONCLUSION: We present a novel use of the multi-input display program on the da Vinci Surgical System to facilitate the performance of intraoperative endoscopies during complex robotic operations. Our study offers another potentially beneficial application of the robotic surgery platform toward integration and simplification of combining additional procedures with complex minimally invasive operations.ope

Novel application of simultaneous multi-image display during complex robotic abdominal procedures

The surgical robot offers the potential to integrate multiple views into the surgical console screen, and for the assistant’s monitors to provide real-time views of both fields of operation. This function has the potential to increase patient safety and surgical efficiency during an operation. Herein, we present a novel application of the multi-image display system for simultaneous visualization of endoscopic views during various complex robotic gastrointestinal operations. All operations were performed using the da Vinci Surgical System (Intuitive Surgical, Sunnyvale, CA, USA) with the assistance of Tilepro, multi-input display software, during employment of the intraoperative scopes. Three robotic operations, left hepatectomy with intraoperative common bile duct exploration, low anterior resection, and radical distal subtotal gastrectomy with intracorporeal gastrojejunostomy, were performed by three different surgeons at a tertiary academic medical center. The three complex robotic abdominal operations were successfully completed without difficulty or intraoperative complications. The use of the Tilepro to simultaneously visualize the images from the colonoscope, gastroscope, and choledochoscope made it possible to perform additional intraoperative endoscopic procedures without extra monitors or interference with the operations. We present a novel use of the multi-input display program on the da Vinci Surgical System to facilitate the performance of intraoperative endoscopies during complex robotic operations. Our study offers another potentially beneficial application of the robotic surgery platform toward integration and simplification of combining additional procedures with complex minimally invasive operations

Current engineering developments for robotic systems in flexible endoscopy

The past four decades have seen an increase in the incidence of early-onset gastrointestinal cancer. Because early-stage cancer detection is vital to reduce mortality rate, mass screening colonoscopy provides the most effective prevention strategy. However, conventional endoscopy is a painful and technically challenging procedure that requires sedation and experienced endoscopists to be performed. To overcome the current limitations, technological innovation is needed in colonoscopy. In recent years, researchers worldwide have worked to enhance the diagnostic and therapeutic capabilities of endoscopes. The new frontier of endoscopic interventions is represented by robotic flexible endoscopy. Among all options, self-propelling soft endoscopes are particularly promising thanks to their dexterity and adaptability to the curvilinear gastrointestinal anatomy. For these devices to replace the standard endoscopes, integration with embedded sensors and advanced surgical navigation technologies must be investigated. In this review, the progress in robotic endoscopy was divided into the fundamental areas of design, sensing, and imaging. The article offers an overview of the most promising advancements on these three topics since 2018. Continuum endoscopes, capsule endoscopes, and add-on endoscopic devices were included, with a focus on fluid-driven, tendon-driven, and magnetic actuation. Sensing methods employed for the shape and force estimation of flexible endoscopes were classified into model- and sensor-based approaches. Finally, some key contributions in molecular imaging technologies, artificial neural networks, and software algorithms are described. Open challenges are discussed to outline a path toward clinical practice for the next generation of endoscopic devices

Development of a Highly Flexible and Stretchable Tubular Shape Tactile Sensor Array

University of Minnesota M.S.E.E. thesis. August 2016. Major: Electrical Engineering. Advisors: Jing Bai, Debao Zhou. 1 computer file (PDF); viii, 68 pages.Highly flexible skin-like sensors, such as electrical skin (e-skin) sensor for pressure measurement, have the potential to provide quantitative physical contact assessments, when equipped on household and medical devices to benefit human society. One of the promising applications is to monitor the contact pressure of a colonoscope to the colonic wall during a colonoscopy to reduce the possibility of perforation and hemorrhaging.Colon, as the largest intestine, is a long winding tube at end of human's digestive tract. Many disorders affect the colon's ability to work properly, thus the American Cancer Society suggests that citizens over 50 years old should be subject to a colon screen test. However, risks do exist during colonoscopy. A rate of 0.19% perforation occurs in the diagnostic colonoscopy. Many attempts have been made to fabricate highly stretchable electronic devices, but no effort has been made to design or investigate the mechanical behaviors of a tubular-shaped e-skin that meet the need for controlling the risks during colonoscopy. In this project, a high performance three-layer tactile sensor array was designed and fabricated, and a pressure detection system was set up as well. The operating mode was thoroughly investigated and the pressure detection on curved surface, such as a tube was realized. A detailed study about false positive error was performed to improve the sensor’s reliability and accuracy. Based on a tubular-shaped, highly flexible skin-like sensor array we developed, we conducted both modeling and experimental studies on the change of the maximum pressure distribution of a tubular e-skin sensor under various bending conditions with and without external compressive forces. These studies revealed the value of the maximum stress on a tubular shaped e-skin sensor array when bent. The measuring errors due to bending in pressure detection during colonoscopy can be quantified for compensation. Thus, high accuracy diagnose can be achieved. Based on all these work, the pressure detection in the colon-simulator was successfully realized. The results could also be used to address strategies on optimizing the design of tactile sensors for other medical application

Development of A Kinetic Model For Loop-Free Colonoscopy Technology

The colonoscope is an important tool in diagnosis and management of diseases of the colon. One of the ongoing challenges with this device is that the colonoscope may form a loop together with the colon during the procedure. The result of the loop is that further insertion of the scope in the colon may not be possible. The loop may also cause risks of perforation of the colon and pain in the patient. There are currently several existing devices to overcome loop formation in colonoscopy, some of which have been introduced in clinical work. However, empirical assessment shows that these devices do not work very well. This is the motivation for the research presented in this thesis. In this thesis, a new paradigm of thinking, “doctor-assisted colonoscopy,” is proposed to overcome loop formation. In this new approach, the physician’s role is enhanced with new information that is acquired by sensors outside the human body and inferred from the mathematical model. It is referred to as a kinetic model due to the fact that this model describes the kinetic behaviour of the scope. This thesis is devoted to development of this kinetic model. In this study, the model of the colonoscope and the model of the colon are developed based on the Timoshenko beam theory, and parameters in both models are determined by the experiments. The following conclusions then are made: (1) self-locking of the colonoscope is the most basic cause for a loop to occur, while structural instability of the colonsocope is dependent on the self-locking; (2) both the scope and the colon can be well represented with the Timoshenko beam elements and the Linear Complementary Problem (LCP) formulation derived from Signorini’s law, and Coulom’s law for representation of interactions between the colon and scope is adequate; (3) there are effects from the location, looping, and tip deflection of the scope on flexural rigidity of the scope. Approximately, the flexural rigidity of the CF-Q160L colonoscope ranges from 300 to 650 N•cm2, and its accuracy is proven by a good agreement between the model predicted result and experimental result; (4) Rayleigh damping for the CF-Q160L colonoscope depends more on the mass matrix [M] of the colonoscope than the stiffness matrix [K], which is evident by the large coefficient value of “alpha” (0.3864) and the small coefficient value of “beta” (0.0164). The contributions of this thesis are: (1) the finding that the main cause of the loop is not structural instability of the colonoscope but rather self-locking of the colonoscope, which could lead to design of a “new-generation” colonoscope to avoid the loop; (2) a systematic evaluation of the existing colonoscopy technologies based on the well-proven Axiomatic Design Theory (ADT), which will serve as a guideline for the development of future new colonoscopes in future; (3) an approach to developing a kinetic model of the colonoscope useful to modeling similar objects such as a catheter guide-wire; (4) a novel ex-vivo colonoscopy test-bed with the kinetic and kinematic measurements useful for validation of new designs in colonoscopy technology and also useful for training physicians who perform the colonoscopy procedure; and (5) a new paradigm of thinking for colonoscopy called “doctor-assisted colonoscopy,” which has potential applications to other medical procedures such as catheter-based procedures

Advanced Endoscopic Navigation:Surgical Big Data,Methodology,and Applications

随着科学技术的飞速发展，健康与环境问题日益成为人类面临的最重大问题之一。信息科学、计算机技术、电子工程与生物医学工程等学科的综合应用交叉前沿课题，研究现代工程技术方法，探索肿瘤癌症等疾病早期诊断、治疗和康复手段。本论文综述了计算机辅助微创外科手术导航、多模态医疗大数据、方法论及其临床应用：从引入微创外科手术导航概念出发，介绍了医疗大数据的术前与术中多模态医学成像方法、阐述了先进微创外科手术导航的核心流程包括计算解剖模型、术中实时导航方案、三维可视化方法及交互式软件技术，归纳了各类微创外科手术方法的临床应用。同时，重点讨论了全球各种手术导航技术在临床应用中的优缺点，分析了目前手术导航领域内的最新技术方法。在此基础上，提出了微创外科手术方法正向数字化、个性化、精准化、诊疗一体化、机器人化以及高度智能化的发展趋势。【Abstract】Interventional endoscopy (e.g., bronchoscopy, colonoscopy, laparoscopy, cystoscopy) is a widely performed procedure that involves either diagnosis of suspicious lesions or guidance for minimally invasive surgery in a variety of organs within the body cavity. Endoscopy may also be used to guide the introduction of certain items (e.g., stents) into the body. Endoscopic navigation systems seek to integrate big data with multimodal information (e.g., computed tomography, magnetic resonance images, endoscopic video sequences, ultrasound images, external trackers) relative to the patient's anatomy, control the movement of medical endoscopes and surgical tools, and guide the surgeon's actions during endoscopic interventions. Nevertheless, it remains challenging to realize the next generation of context-aware navigated endoscopy. This review presents a broad survey of various aspects of endoscopic navigation, particularly with respect to the development of endoscopic navigation techniques. First, we investigate big data with multimodal information involved in endoscopic navigation. Next, we focus on numerous methodologies used for endoscopic navigation. We then review different endoscopic procedures in clinical applications. Finally, we discuss novel techniques and promising directions for the development of endoscopic navigation.X.L. acknowledges funding from the Fundamental Research Funds for the Central Universities. T.M.P. acknowledges funding from the Canadian Foundation for Innovation, the Canadian Institutes for Health Research, the National Sciences and Engineering Research Council of Canada, and a grant from Intuitive Surgical Inc