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PubMed2006

Radical cystectomy with ileal conduit diversion: early prospective evaluation of the impact of robotic assistance.

OBJECTIVE: To compare the performance of radical cystectomy with ileal conduit diversion by standard methods with that using the assistance of the daVinci robotic system (Intuitive Surgical, Sunnyvale, CA, USA). PATIENTS AND METHODS: From November 2003 to August 2005, we performed 30 radical cystectomies with ileal conduit urinary diversions on patients with bladder cancer. Seven patients (one woman) had a cystectomy with the daVinci system and 23 (nine women) had a standard cystectomy. Data were collected prospectively, including estimated blood loss (EBL), transfusion requirement, operative duration, hospital stay and body mass index (BMI), and compared. RESULTS: The mean EBL and transfusion requirements for standard and daVinci-assisted cases was 1109 and 479 mL (P = 0.002) and 2.7 and 1.6 units (P = 0.14), respectively. Four of seven patients received a transfusion in the robotic group, and 20 of 23 in the standard group (P = 0.084). The mean operative duration was 638 and 507 min (P = 0.005) for the daVinci and standard group, respectively, with respective mean hospital stays of 11 and 13 days (P = 0.52). There was no difference in patient BMI between the groups (P = 0.22). CONCLUSION: The daVinci-assisted cystectomy appears to offer some advantages over standard cystectomy. Larger randomized studies are needed to confirm these findings.

Aged↗

PubMed2006

Does obesity influence the operative course or complications of robot-assisted laparoscopic prostatectomy.

OBJECTIVE: To determine if obesity is associated with prolonged surgery or more complications during and after surgery in patients undergoing robot-assisted laparoscopic prostatectomy (RALP). PATIENTS AND METHODS: Between December 2003 and September 2005 data were collected prospectively for all patients undergoing RALP. Obesity was defined as a body mass index of > or = 30 kg/m2. The duration of surgery was recorded, determining the duration of steps, including overall, robotic assistance, and vesico-urethral anastomosis. In all, 285 patients had RALP by one of two surgeons; 236 were classified as not obese and 49 as obese. RESULTS: The characteristics of the two groups were similar before and after RALP (mean age 60.7 vs 60.3 years, prostate-specific antigen level 7.9 vs 7.9 ng/mL, prostate weight 47.3 vs 45.3 g, length of stay 3.2 vs 3.5 days, and indwelling catheterization 8.3 vs 7.9 days). The mean duration of surgical steps was less for the non-obese than the obese group, with urethral dissection requiring 16 vs 19.3 min (P < 0.05), anastomotic time 30 vs 36 min (P < 0.01), and port closure 11 vs 14.5 min (P < 0.001), but the total duration of surgery, at 190 vs 205 min, was not significantly different (P = 0.07). In the non-obese group there were seven (3%) prolonged drain tube leaks, vs four (8%) in the obese group (P = 0.08). CONCLUSIONS: Obesity was associated with longer anastomotic times, but the overall duration was similar. Overall complication rates were not significantly different. The continuing follow-up will determine if obesity predisposes patients to greater long-term morbidity after RALP.

Aged↗

PubMed2006

Robotic implantation of a multichamber cardiac resynchronization therapy defibrillator.

Transvenous implantation of a cardiac resynchronization therapy defibrillator (CRT-D) may not be feasible due to anatomic constraints. One of the most notable advances in minimal-access heart surgery has been the introduction of robotic telemanipulation systems. We present a challenging case in which a CRT-D system was implanted using a robotic approach. Feasibility of such an approach expands the horizons for delivery of CRT-D therapy.

Defibrillators, Implantable↗

PubMed2006

Novel robotic catheter remote control system: feasibility and safety of transseptal puncture and endocardial catheter navigation.

OBJECTIVES: The aims of this study were to demonstrate the safety and the feasibility of the robotic catheter remote control system (CCS) in endocardial navigation in all cardiac chambers, as well as facilitation of the transseptal puncture. BACKGROUND: CCS has been developed to facilitate control and precise positioning of catheters within the cardiovascular system. METHODS: CCS consists of a remote catheter manipulator, a set up joint, a physician workstation, and a steerable guide catheter (SGC) and sheath. A conventional 4-mm tip catheter was inserted through the SGC to perform mapping of five predefined targets in each cardiac chamber. Seven mongrel dogs were used in this study. Intracardiac echocardiography and three-dimensional (3-D) electroanatomical mapping were integrated with CCS to facilitate catheter manipulation and to guide transseptal puncture. The time to complete the transseptal puncture and the time to complete access to the predefined targets in each cardiac chamber were measured. Gross and microscopic examinations of the accessed and ablation sites were performed to evaluate safety. RESULTS: Transseptal puncture was performed successfully in all animals with a mean time of 7 +/- 3 minutes. Procedure times to access the five targets in the right atrium, right ventricle, left atrium, and left ventricle were 5.6 +/- 1.7, 4.6 +/- 1.5, 13.5 +/- 11.0, 7.0 +/- 2.9 minutes, respectively. There were no intracardiac damages associated with catheter manipulation noted in the excised hearts. CONCLUSIONS: Endocardial catheter navigation and mapping using the robotic catheter remote control is safe and feasible. Moreover, the CCS could be used to perform transseptal puncture and left atrial instrumentation.

Animals↗

PubMed2003

Robotic mitral valve surgery: a technologic and economic revolution for heart centers.

A renaissance in cardiac surgery is occurring. Cardiac operations are being performed through smaller incisions with enhanced technologic assistance. Specifically, minimally invasive mitral valve surgery has become standard for many surgeons. At our institution, we have developed a robotic mitral surgery program with the da Vinci telemanipulation system, which has recently gained Food and Drug Administration approval. This system allows the surgeon to perform complex mitral valve operations through small port sites rather than a traditional median sternotomy. Our techniques and initial results are reported. Despite procedural success, these devices are not inexpensive and hospitals will have to justify their purchase. The implementation of robotic surgery has forced us to compare costs and benefits compared with conventional cardiac surgery. Nevertheless, our desire for improved and less traumatic patient care will drive this new technology, which will serve as a good model for us to study over the next several years.

Aged↗

PubMed2005

Automated knot tying for fixation in minimally invasive, robot-assisted cardiac surgery.

Cardiovascular disease (CVD) is perhaps the most significant worldwide health issue. While open-heart surgery remains the predominant treatment, significant advancements have been made in minimally invasive surgery (MIS) and minimally invasive robot-assisted (MIRA) surgery. MIRA techniques offer many advantages over open-heart procedures and have extended the capabilities of MIS. However, these benefits come at the cost of increased operating times due to time spent tying knots. The additional bypass time limits patient access and is the most significant barrier to the adoption of MIRA techniques. This research seeks to overcome this barrier by designing a device for MIRA cardiac procedures that automates the knotting of sutures. If this task can be automated while ensuring the delivery of high-quality knots, great progress can be made in transforming the field. MIRA cardiac procedures can move from novel procedures performed by a select group of surgeons on a limited pool of patients to a viable alternative available to the majority of patients with CVD. In this research we propose a design for a self-contained device that delivers a locking knot. Results suggest that consistent knots can be delivered at a time savings of 12.5% and 26.4% over manual knots for trained and untrained users of a surgical robot, respectively.

Cardiac Surgical Procedures↗

PubMed2006

An efficient robotic tendon for gait assistance.

A robotic tendon is a spring based, linear actuator in which the stiffness of the spring is crucial for its successful use in a lightweight, energy efficient, powered ankle orthosis. Like its human analog, the robotic tendon uses its inherent elastic nature to reduce both peak power and energy requirements for its motor. In the ideal example, peak power required of the motor for ankle gait is reduced from 250 W to just 77 W. In addition, ideal energy requirements are reduced from nearly 36 J to just 21 J. Using this approach, an initial prototype has provided 100% of the power and energy necessary for ankle gait in a compact 0.95 kg package, seven times less than an equivalent motor/gearbox system.

Achilles Tendon↗

PubMed1993

The use of robotics technology to study human joint kinematics: a new methodology.

Robotics technologies have been modified to control and measure both the force and position of synovial joints for the study of joint kinematics. One such system was developed to perform kinematic testing of a human joint. A 6-axis articulated robotic manipulator with 6 degrees of freedom (DOF) of motion was designed and constructed; a mathematical description for joint force and position was devised; and hardware and software to control forces applied to the joint, as well as position of the joint, were developed. The new methodology was utilized to simulate physiological loading conditions and to perform an anterior-posterior (A-P) translation test on a human cadaveric knee. Testing showed that this new system can stimulate complex loading conditions and also measure the resulting joint kinematics.

Algorithms↗

PubMed1991

Dynamics and control of robotic systems worn by humans.

This article describes the dynamics, control, and stability of extenders, robotic systems worn by humans for material handling tasks. Extenders are defined as robot manipulators which extend (i.e., increase) the strength of the human arm in load maneuvering tasks, while the human maintains control of the task. Part of the extender motion is caused by physical power from the human; the rest of the extender motion results from force signals measured at the physical interfaces between the human and the extender, and the load and the extender. Therefore, the human wearing the extender exchanges both power and information signals with the extender. The control technique described here lets the designer define an arbitrary relationship between the human force and the load force. A set of experiments on a two-dimensional non-direct-drive extender were done to verify the control theory.

Arm↗

PubMed2006

Resampling: an optimization method for inverse planning in robotic radiosurgery.

By design, the range of beam directions in conventional radiosurgery are constrained to an isocentric array. However, the recent introduction of robotic radiosurgery dramatically increases the flexibility of targeting, and as a consequence, beams need be neither coplanar nor isocentric. Such a nonisocentric design permits a large number of distinct beam directions to be used in one single treatment. These major technical differences provide an opportunity to improve upon the well-established principles for treatment planning used with GammaKnife or LINAC radiosurgery. With this objective in mind, our group has developed over the past decade an inverse planning tool for robotic radiosurgery. This system first computes a set of beam directions, and then during an optimization step, weights each individual beam. Optimization begins with a feasibility query, the answer to which is derived through linear programming. This approach offers the advantage of completeness and avoids local optima. Final beam selection is based on heuristics. In this report we present and evaluate a new strategy for utilizing the advantages of linear programming to improve beam selection. Starting from an initial solution, a heuristically determined set of beams is added to the optimization problem, while beams with zero weight are removed. This process is repeated to sample a set of beams much larger compared with typical optimization. Experimental results indicate that the planning approach efficiently finds acceptable plans and that resampling can further improve its efficiency.

Computer Simulation↗

PubMed2001

Unsupervised learning and temporal context to recall complex robot trajectories.

An unsupervised neural network is proposed to learn and recall complex robot trajectories. Two cases are considered: (i) A single trajectory in which a particular arm configuration (state) may occur more than once, and (ii) trajectories sharing states with each other. Ambiguities occur in both cases during recall of such trajectories. The proposed model consists of two groups of synaptic weights trained by competitive and Hebbian learning laws. They are responsible for encoding spatial and temporal features of the input sequences, respectively. Three mechanisms allow the network to deal with repeated or shared states: local and global context units, neurons disabled from learning, and redundancy. The network reproduces the current and the next state of the learned sequences and is able to resolve ambiguities. The model was simulated over various sets of robot trajectories in order to evaluate learning and recall, trajectory sampling effects and robustness.

Algorithms↗

PubMed2001

Adaptive control of mobile robots using a neural network.

A Neural Network - based control approach for mobile robot is proposed. The weight adaptation is made on-line, without previous learning. Several possible situations in robot navigation are considered, including uncertainties in the model and presence of disturbance. Weight adaptation laws are presented as well as simulation results.

Neural Networks, Computer↗

PubMed1997

Real-time neural network based camera localization and its extension to mobile robot control.

The feasibility of using neural networks for camera localization and mobile robot control is investigated here. This approach has the advantages of eliminating the laborious and error-prone process of imaging system modeling and calibration procedures. Basically, two different approaches of using neural networks are introduced of which one is a hybrid approach combining neural networks and the pinhole-based analytic solution while the other is purely neural network based. These techniques have been tested and compared through both simulation and real-time experiments and are shown to yield more precise localization than analytic approaches. Furthermore, this neural localization method is also shown to be directly applicable to the navigation control of an experimental mobile robot along the hallway purely guided by a dark wall strip. It also facilitates multi-sensor fusion through the use of multiple sensors of different types for control due to the network's capability of learning without models.

Algorithms↗

PubMed2003

A basal ganglia inspired model of action selection evaluated in a robotic survival task.

The basal ganglia system has been proposed as a possible neural substrate for action selection in the vertebrate brain. We describe a robotic implementation of a model of the basal ganglia and demonstrate the capacity of this system to generate adaptive switching between several acts when embedded in a robot that has to "survive" in a laboratory environment. A comparison between this brain-inspired selection mechanism and classical "winner-takes-all" selection highlights some adaptive properties specific to the model, such as avoidance of dithering and energy-saving. These properties derive, in part, from the capacity of simulated basal ganglia-thalamo-cortical loops to generate appropriate "behavioral persistence".

Animals↗

PubMed2000

Combining dynamic and static robotic telepathology: a report on 184 consecutive cases of frozen sections, histology and cytology.

The aim of this paper is to describe the experiments carried out to evaluate the diagnostic efficacy of a dynamic-robotic telepathology system for the delivery of pathology services to distant hospitals. The system provides static/dynamic features and the remote control of a robotized microscope over 4 ISDN lines. For evaluation purposes, 184 consecutive cases of frozen sections (60), gastrointestinal pathology (64), and urinary cytology (60) have been diagnosed at a distance using the system, and the telediagnosis obtained in this way has been compared with the traditional microscopic diagnosis. Diagnostic agreement ranged from 90% in urinary cytology to 100% in frozen sections. The results obtained suggest that such a system can be considered a useful tool for supporting the pathology practice in isolated hospitals.

Digestive System↗

PubMed2002

Robot-assisted endoscopic intrauterine myelomeningocele repair: a feasibility study.

BACKGROUND: Animal experiments have suggested that the intrauterine environment causes secondary injury to the congenitally dysplastic spinal cord. This in turn suggests that early closure of the myelomeningocele sac might prevent secondary injury and therefore improve neurologic outcome. This study was designed to examine the technical feasibility of performing intrauterine myelomeningocele repair using a robot-assisted endoscopic system in an animal model. METHODS: Six fetal sheep underwent creation and repair of a full-thickness skin lesion using the da Vinci system. RESULTS: With the device's advanced articulated instruments and three-dimensional optics, it was possible to endoscopically repair the induced skin defects. CONCLUSION: We conclude that, with the recent evolution in robotics and minimally invasive techniques, intrauterine endoscopic surgery has become a realistic goal that promises to reduce the associated risks of fetal surgery and extend the indications for its use.

Animals↗

PubMed1990

Configuration of a robot dedicated to stereotactic surgery.

The design of a robot for functional stereotactic surgery which is under construction in our laboratory is described. The main features include operation inside the computed tomographic (CT) scanner, the possibility of intraoperative CT scanning and complete handling of the stereotactic probes by the robot.

Brain Diseases↗

PubMed2001

Evolving control metabolisms for a robot.

This article demonstrates a new method of programming artificial chemistries. It uses the emerging capabilities of the system's dynamics for information-processing purposes. By evolution of metabolisms that act as control programs for a small robot one achieves the adaptation of the internal metabolic pathways as well as the selection of the most relevant available exteroceptors. The underlying artificial chemistry evolves efficient information-processing pathways with most benefit for the desired task, robot navigation. The results show certain relations to such biological systems as motile bacteria.

Metabolism↗