Robotic Forceps Research Articles

Robotic Artificial Chordal Replacement for Repair of Mitral Valve Prolapse

Artificial chordal replacement (ACR) has emerged as a superior method of mitral valve repair with excellent early and late efficacy. It is also ideal to combine with robotic techniques for correction of mitral prolapse, and this article presents a current method of robotic Gore-Tex ACR. Patients with isolated posterior leaflet prolapse are approached with the fourth-generation DaVinci robotic system and endoaortic balloon occlusion. A pledgetted anchor stitch is placed in a papillary muscle, and a 2-o Gore-Tex suture is passed through the anchor pledget. After full annuloplasty ring placement, the Gore-Tex suture is woven into the prolapsing segment and positioned temporarily with robotic forceps. Chordal length is then "adjusted" by lengthening or shortening the temporary knot over 1-cm increments as the valve is tested by injection of cold saline into the ventricle. After achieving good leaflet position and valve competence, the chord is tied permanently. The "adjustable" ACR procedure preserves leaflet surface area and produces a competent valve in the majority of patients. Postoperative transesophageal echo shows a large surface area of coaptation. Patient recovery is facilitated by the minimally invasive approach, while long-term stability of similar open ACR techniques have been excellent with a 2% to 3% failure rate over 10 years of follow-up. Robotic Gore-Tex ACR without leaflet resection is a reproducible procedure that simplifies mitral repair for prolapse. The outcomes observed in early robotic applications have been excellent. It is suggested that most patients with simple prolapse might validly be approached in this manner.

Design Optimization of Single-Port Minimally Invasive Intervention Devices

Despite the success of multiple-port minimally invasive intervention (MII) systems, current research is fast moving away from standard, kinematically rigid MII instruments toward more flexible, highly articulated devices, such as robotic catheters, probes, and forceps. These new devices afford surgeons the same dexterity and range of motion as multiple-port systems while using only a single incision. Single-port MII devices hold the promise of facilitating procedures in small, geometrically complex spaces, such as those seen cardiothoracic surgery, with even lower risks of infection and patient discomfort than possible with multiple-port systems. However, the mechanical sophistication of these robotic devices requires careful consideration of morphological design to ensure that the complexity and cost of design is not economically prohibitive enough to outweigh the clinical benefits of improved robot flexibility. This study focuses on the intelligent design of a kinematically redundant, single-port MII robot architecture by way of morphological optimization. This MII device morphology is optimized to access the cardiothoracic cavity through a single 12 mm subxiphoid port and reach several regions of interest, consistent with procedures such as epicardial ablation and therapeutic substance injection, with minimal physiologic disturbance. The optimization process employs a recently developed morphological fitness metric to measure a candidate morphology's ability to navigate the cardiothoracic environment and perform surgical maneuvers with high end-effector flexibility while maintaining safe distances from anatomical structures. This fitness metric uses a Jacobian-based formulation to quantify a robot's capacity to avoid collisions with motion impediments and to minimize the mechanical torque required for the intended task. In addition to performance-based criterion, this optimization process also considers design factors such as part manufacturability and expense which heavily influence economic feasibility. Morphological optimization is performed by searching the mechanical design parameter space, which consists of part dimensions and linkage types, using genetic algorithms. The execution of specific surgical maneuvers is simulated for each candidate morphology until the fitness metric is maximized. Final simulations of the optimized device morphology working in the cardiothoracic cavity are performed to demonstate the functional advantages of the optimized single-port robot over current multiple-port systems.

Development of multi‐degree‐of‐freedom bilateral forceps robot system using FPGA

AbstractFast growing use of minimally invasive endoscopic surgeries called for development of robots assisting in such procedures. However, existing surgical robots cannot transmit tactile sensation to the operator. To overcome this shortcoming, a bilateral teleoperation method was developed making it possible to accurately convey tactile sensation in single‐degree‐of‐freedom forceps robots. This paper deals with the development of a multi‐degree‐of‐freedom bilateral forceps robot system for surgical procedures which can adapt to actual conditions of the surgery.Bilateral teleoperation of multi‐degree‐of‐freedom robots requires exchange of environmental information between master and slave devices in common coordinates. In this study we adopted mode coordinates which are better related to the motion of the robot. We also proposed a method to decouple the mechanical interference in mode coordinates. An FPGA‐based controller introduced in this study makes it possible to reduce data processing time and to use hardware‐based real‐time control. As a result, multi‐degree‐of‐freedom force feedback is attained. The experimental results show the viability of the proposed method. © 2008 Wiley Periodicals, Inc. Electron Comm Jpn, 91(6): 23–33, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10118

Improvement of Tactile Sensation of a Bilateral Forceps Robot by a Switching Virtual Model

Interest in tele-operation started many decades ago. Today, tele-operation is becoming a reality with improved tele-communication systems. Bilateral control is also a subset of tele-operation. Usually in bilateral control, force position information is exchanged between a master and a slave. This structure successfully transmits tactile sensation from the slave environment to the master operator. A bilateral control system is capable of transmitting tactile sensation to the master side. This capability is also known as the transparency of the system. If bilateral control is used in a surgery, ideally the medical doctor should sense the feeling coming from the body tissue together with the reaction force of the special surgical tool. We have previously proposed a method to eliminate the special surgical tool with a simple tool tip and a virtual tool model. However, a physical tool as well as the proposed virtual tool add impedance to the system. Even if a virtual model is used, impedances are essential to carry out the tool action. In this paper, a novel method is proposed to switch off and on the virtual tool model when the tool action can be replaced by the environmental reaction forces. An experiment was carried out using a bilaterally controlled forceps robot. Results show the applicability of the idea.

Virtual tool for bilaterally controlled forceps robot‐for minimally invasive surgery

Bilateral control enables an operator to be placed away from the working environment. A slave manipulator usually works at a remote site or in a hazardous environment while the master operator senses the environment through the slave manipulator. Bilateral control can be used in surgeries. Usually doctors are very sensitive to the tactile sensation they feel through medical tools. If bilateral control is used in a surgery, ideally the doctor should perceive the sensation of both the body tissue and the reaction force from the specialized tool. Many surgical instruments are essentially similar at the tool tip while showing some structural differences at the gripping end. Therefore, it is advantageous for an expensive tool to be replaced by a virtual tool together with a simple tool. With the virtual tool, the surgeon should be able to perceive the feeling of the actual tool together with the reaction force coming from the body tissue; this may also reduce the time taken for a tool change during the surgery. In this study, above ideas were implemented in a bilaterally controlled forceps robot and experiments were carried out to test the applicability of the concept. Bilateral control is used as the method of tactile feedback. Disturbance observer is used for robust control. Reaction force observer is used in place of a force sensor. Virtual model is used in place of the special tool properties. A virtual spring acting at the end of the forceps, was implemented to a bilateral control system, so that the operator at the master side could perceive the feeling of the spring together with reaction forces from the surgical environment. Operator could feel the vivid sensation of the environment through the master manipulator. The virtual model adds a load to the system. The master and slave responses are slightly different, but the result is good enough for the application. This novel approach could be used in many master-slave applications.

1A1-M04 ファジィコーチ・プレイヤーシステムによる音声指示を用いたロボット鉗子の操作(人間機械協調)

1A1-M04 ファジィコーチ・プレイヤーシステムによる音声指示を用いたロボット鉗子の操作(人間機械協調)

Development of Robotic Forceps for Laparoscopic Surgery

Minimally invasive surgery accelerates postoperative recovery, but can only be applied by surgeons having advanced conduct skills. We developed a master-slave manipulator, i.e., robotic forceps for laparoscopic surgery that enhances surgical skill. Robotic forceps consists of a master-slave manipulator, a support component, a controller, an operating conditions display, and a foot switch for changing operating conditions. This paper details specifications and components of robotic forceps and evaluates conductance, such as measurement of the slave hand’s grip and suturing and ligaturing, conducted on a sponge stomach model. A comparison of support function in experiments demonstrates their effectiveness.

1A1-A12 深部脳神経外科手術支援システムの高機能化に関する研究

In neurosurgery, surgeons have to perform minute and precise manipulation with poor visibility due to blood or cerebrospinal fluid, and it is particularly difficult to operate in the deep surgical field. To overcome these difficulties, the authors have developed a robotic system to support micro-neurosurgery. Based on the evaluation, sophistication of the system is implemented. To ensure the sterilization of the forceps, and to respond to many kind of surgical tools, the authors have developed robotic forceps which are composed of the three components. The connection of these components can be performed with simple operation. And not to prevent visual system, the diameter of the forceps is reduced to 2.5[mm].

2A1-N-114 腹腔鏡下手術支援用ロボット鉗子システムの開発(医療福祉ロボティクス・メカトロニクス3,生活を支援するロボメカ技術のメガインテグレーション)

2A1-N-114 腹腔鏡下手術支援用ロボット鉗子システムの開発(医療福祉ロボティクス・メカトロニクス3,生活を支援するロボメカ技術のメガインテグレーション)

外科医による腹腔鏡下手術支援用ロボット鉗子の操作性評価(医療・福祉ロボティクス・メカトロニクス4)

外科医による腹腔鏡下手術支援用ロボット鉗子の操作性評価(医療・福祉ロボティクス・メカトロニクス4)