David I. Lee

A consensus document on robotic surgery

“Robotic surgery” originated as an imprecise term, but it has been widely used by both the medical and lay press and is now generally accepted by the medical community. The term refers to surgical technology that places a computer-assisted electromechanical device in the path between the surgeon and the patient. A more scientifically accurate term for current devices would be “remote telepresence manipulators” because available technology does not generally function without the explicit and direct control of a human operator. For the purposes of the document, we define robotic surgery as a surgical procedure or technology that adds a computer technology–enhanced device to the interaction between a surgeon and a patient during a surgical operation and assumes some degree of control heretofore completely reserved for the surgeon. For example, in laparoscopic surgery, the surgeon directly controls and manipulates tissue, albeit at some distance from the patient and through a fulcrum point in the abdominal wall. This differs from the use of current robotic devices, whereby the surgeon sits at a console, typically in the operating room but outside the sterile field, directing and controlling the movements of one or more robotic arms. Although the surgeon still maintains control over the operation, the control is indirect and effected from an increased distance. This definition of robotic surgery encompasses micromanipulators, remotely controlled endoscopes, and console-manipulator devices. The key elements are enhancements of the surgeon’s abilities—be they vision, tissue manipulation, or tissue sensing—and alteration of the traditional direct local contact between surgeon and patient.

Training, credentialing, proctoring and medicolegal risks of robotic urological surgery: recommendations of the society of urologic robotic surgeons.

PURPOSE With the exponential growth of robotic urological surgery, particularly with robot assisted radical prostatectomy, guidelines for safe initiation of this technology are a necessity. Currently no standardized credentialing system exists to our knowledge to evaluate surgeon competency and safety with robotic urological surgery performance. Although proctoring is a modality by which such competency can be evaluated, other training tools and guidelines are needed to ensure that the requisite knowledge and technical skills to perform this procedure have been acquired. We evaluated the current status of proctoring and credentialing in other surgical specialties to discuss and recommend its application and implementation specifically for robot assisted radical prostatectomy. MATERIALS AND METHODS We reviewed the literature on safety and medicolegal implications of proctoring and the safe introduction of surgical procedures to develop recommendations for robot assisted radical prostatectomy proctoring and credentialing. RESULTS Proctoring is an essential mechanism for robot assisted radical prostatectomy institutional credentialing and should be a prerequisite for granting unrestricted privileges on the robot. This should be differentiated from preceptoring, wherein the expert is directly involved in hands-on training. Advanced technology has opened new avenues for long-distance observation through teleproctoring. Although the medicolegal implications of an active surgical intervention by a proctor are not clearly defined, the role as an observer should grant immunity from malpractice liability. CONCLUSIONS The implementation of guidelines and proctoring recommendations is necessary to protect surgeons, proctors, institutions and, above all, the patients who are associated with the institutional introduction of a robot assisted radical prostatectomy program. With no current guidelines we anticipate this article will serve as a catalyst of interorganizational discussion to initiate regulatory oversight of surgeon certification and proctorship.

Tool Contact Acceleration Feedback for Telerobotic Surgery

Minimally invasive telerobotic surgical systems enable surgeons to perform complicated procedures without large incisions. Unfortunately, these systems typically do not provide the surgeon with sensory feedback aside from stereoscopic vision. We have, thus, developed VerroTouch, a sensing and actuating device that can be added to Intuitive Surgicals existing da Vinci S Surgical System to provide auditory and vibrotactile feedback of tool contact accelerations. These cues let the surgeon feel and hear contact with rough textures as well as the making and breaking of contact with objects and other tools. To evaluate the merits of this approach, we had 11 surgeons use an augmented da Vinci S to perform three in vitro manipulation tasks under four different feedback conditions: with no acceleration feedback, with audio feedback, with haptic feedback, and with both audio and haptic. Subjects expressed a significant preference for the inclusion of tool contact acceleration feedback, although they disagreed over which sensory modality was best. Other survey responses and qualitative written comments indicate that the feedback may have improved the subjects concentration and situational awareness by strengthening the connection between the surgeon and the surgical instruments. Analysis of quantitative task metrics shows that the feedback neither improves nor impedes the performance of the chosen tasks.

Positive surgical margins after robotic assisted radical prostatectomy: A multi-institutional study

PURPOSE Positive surgical margins are an independent predictive factor for biochemical recurrence after radical prostatectomy. We analyzed the incidence of and associative factors for positive surgical margins in a multi-institutional series of 8,418 robotic assisted radical prostatectomies. MATERIALS AND METHODS We analyzed the records of 8,418 patients who underwent robotic assisted radical prostatectomy at 7 institutions. Of the patients 323 had missing data on margin status. Positive surgical margins were categorized into 4 groups, including apex, bladder neck, posterolateral and multifocal. The records of 6,169 patients were available for multivariate analysis. The variables entered into the logistic regression models were age, body mass index, preoperative prostate specific antigen, biopsy Gleason score, prostate weight and pathological stage. A second model was built to identify predictive factors for positive surgical margins in the subset of patients with organ confined disease (pT2). RESULTS The overall positive surgical margin rate was 15.7% (1,272 of 8,095 patients). The positive surgical margin rate for pT2 and pT3 disease was 9.45% and 37.2%, respectively. On multivariate analysis pathological stage (pT2 vs pT3 OR 4.588, p<0.001) and preoperative prostate specific antigen (4 or less vs greater than 10 ng/ml OR 2.918, p<0.001) were the most important independent predictive factors for positive surgical margins after robotic assisted radical prostatectomy. Increasing prostate weight was associated with a lower risk of positive surgical margins after robotic assisted radical prostatectomy (OR 0.984, p<0.001) and a higher body mass index was associated with a higher risk of positive surgical margins (OR 1.032, p<0.001). For organ confined disease preoperative prostate specific antigen was the most important factor that independently correlated with positive surgical margins (4 or less vs greater than 10 ng/ml OR 3.8, p<0.001). CONCLUSIONS The prostatic apex followed by a posterolateral site was the most common location of positive surgical margins after robotic assisted radical prostatectomy. Factors that correlated with cancer aggressiveness, such as pathological stage and preoperative prostate specific antigen, were the most important factors independently associated with an increased risk of positive surgical margins after robotic assisted radical prostatectomy.

Urinary incontinence after robot-assisted radical prostatectomy: pathophysiology and intraoperative techniques to improve surgical outcome.

Robot‐assisted radical prostatectomy has been shown to have comparable and possibly improved postoperative continent rates compared with retropubic and laparoscopic radical prostatectomy. However, postoperative urinary incontinence has remained one of the most bothersome postoperative complications. The basic concept of the intraoperative technique to improve postoperative urinary continence is to maintain as normal anatomical and functional structure in the pelvis as possible. Therefore, improved knowledge of the normal structure in the pelvis should lead to a greater understanding of the pathophysiology of urinary incontinence, and further development of intraoperative techniques to improve the outcomes of urinary continence. It might be necessary to carry out three steps to realize improvement of the early return of urinary continence after robot‐assisted radical prostatectomy: (i) preservation (bladder neck, neurovascular bundle, puboprostatic ligament, pubovesical complex, and/or urethral length, etc.); (ii) reconstruction (posterior and/or anterior reconstruction, and/or reattachment of the arcus tendineus to the bladder neck, etc.); and (iii) reinforcement (bladder neck plication and/or sling suspension, etc.). On the basis of these steps, further modifications during robot‐assisted radical prostatectomy should be developed to improve urinary continence and quality of life after robot‐assisted radical prostatectomy.

Future perspectives in robotic surgery

Whats known on the subject? and What does the study add?

Novel approach to minimizing trocar sites during challenging hand-assisted laparoscopic surgery utilizing the Gelport: trans-gel instrument insertion and utilization.

PURPOSE We present a novel technique for modified application of a hand-assist device, the Gelport (Applied Medical Resources, Rancho Santa Margarita, CA), which uses a gel for intra-abdominal access. MATERIALS AND METHODS A 53-year-old woman with a history of rectal cancer treated by abdominoperineal resection, ileostomy, subsequent reanastomosis, chemotherapy, and radiation presented with a 6-cm upper-pole left renal mass. Staging was negative, and a CT scan showed no evidence of lymphadenopathy or renal vein involvement. The patient elected to undergo a hand-assisted laparoscopic radical nephrectomy. Numerous intra-abdominal adhesions were encountered during initial periumbilical hand port placement. The initial adhesions were taken down in an open fashion; however, the proposed trocar sites still could not be exposed. The Gelport was placed, and a laparoscope was passed directly through the established central opening and the gel. A working instrument was then passed through the gel itself, allowing adhesiolysis under direct laparoscopic vision. RESULTS The nephrectomy was completed laparoscopically in 4 hours and 15 minutes with lysis of adhesion occupying 90 minutes of the operative time. The estimated blood loss was 150 mL. Despite the technical difficulty of the case, the procedure was completed laparoscopically with two standard 12-mm trocars and a 5-mm lateral retraction trocar. CONCLUSION The Gelport permits simultaneous insertion of the surgeons hand and a working laparoscopic instrument. This allows for maximally efficient utilization of the incision made for hand-assist device placement and may minimize the need for additional trocars during challenging laparoscopic cases.

Laparoscopic Cyst Decortication in Autosomal Dominant Polycystic Kidney Disease: Impact on Pain, Hypertension, and Renal Function

BACKGROUND AND PURPOSE In patients with autosomal dominant polycystic kidney disease (ADPKD), laparoscopic cyst decortication (LCD) has been proposed as a means to relieve chronic cyst-related pain. We present our 7-year experience with LCD for ADPKD with regard to pain relief, hypertension, and renal function. PATIENTS AND METHODS Between August 1994 and February 2001, 29 ADPKD patients with chronic pain (N=29), hypertension (N=21), and renal insufficiency (N=10) underwent 35 LCD procedures. Every detectable cyst within 2 mm of the renal surface was treated. Pain relief was assessed using a pain analog scale; relative pain relief (RPR) equaled (preoperative pain score) - (postoperative pain score)/(preoperative pain score). Hypertension was evaluated using the antihypertensive therapeutic index (ATI): [(dose of blood pressure medication 1/max dose 1) + (dose med 2/max dose 2) + etc.] x 10. Renal function was assessed using the Cockcroft and Gault formula for creatinine clearance. RESULTS The mean operating room time was 4.9 hours (range 2.6-6.6 hours) with no conversions to open surgery. An average of 220 cysts (range 4-692) were treated per patient. The mean follow-up was 32.3 months (range 6-72 months). The RPR was 58%, 47%, and 63% at 12, 24, and 36 months, respectively. At 12, 24, and 36 months, 73%, 52%, and 81% of patients, respectively, noted >50% improvement in their pain compared with the preoperative situation. Five patients became normotensive, and patients improved their ATI by an average of 49% (range 11%-93%). However, six patients had worsening hypertension, with an ATI increase averaging 53% (range 11%-122%), and one patient who was not hypertensive preoperatively has since developed hypertension. The creatinine clearance changed +4%, +7%, and -2% at 12, 24, and 36 months, respectively. Only one patient had a >20% increase in creatinine clearance. The only patients with a >20% decrease in creatinine clearance were those who had a creatinine clearance <30 mg/dL preoperatively (average decrease 34% [range 20%-51%]). CONCLUSIONS For ADPKD patients with debilitating pain, extensive LCD can provide durable relief. In the majority of patients with pain and hypertension, a marked improvement in blood pressure also occurs. Cyst decortication was not associated with worsening renal function; indeed, renal function remained largely unchanged over the 3-year follow-up period.

Novel Use of Indocyanine Green for Intraoperative, Real-time Localization of Ureteral Stenosis During Robot-assisted Ureteroureterostomy

OBJECTIVE To present a novel method to intraoperatively localize ureteral strictures during robot-assisted ureteroureterostomy via indocyanine green (ICG) visualization under near-infrared (NIR) light. MATERIALS AND METHODS Seven patients underwent robot-assisted ureteroureterostomy for ureteral stricture by a single surgeon (D.D.E.). Intraoperative localization of ureteral stricture involved instilling ICG (25 mg in 10 mL distilled water) above and below the level of stenosis through a ureteral catheter or a percutaneous nephrostomy tube, or both. The fluorescent tracer was detected as a green color using the NIR modality on the da Vinci Si (Intuitive Surgical, Sunnyvale, CA). All patients consented to off-label use of ICG after full disclosure. RESULTS Intraoperative ICG injection and visualization under NIR light assisted in the performance of a tension-free anastomosis in all patients. At the time of surgery, mean age was 55.7 ± 12.4 years and mean body mass index was 30.3 ± 5.8 kg/m(2). Mean operative time was 171.3 ± 52.4 minutes, mean estimated blood loss was 175.0 ± 146.5 mL, and mean length of ureteral excision on pathologic analysis was 1.6 ± 0.7 cm. There were no immediate or delayed adverse effects attributable to intraureteral ICG administration. Mean hospital length of stay was 1.6 ± 1.5 days, with no postoperative complications. Mean follow-up was 5.9 ± 1.5 months, and all cases were clinically and radiographically successful at last follow-up. CONCLUSION Intraureteral injection of ICG with visualization under NIR light allows for real-time delineation of the ureter. Additionally, ICG administration aids in discerning healthy ureter from diseased tissue, further assisting successful robotic ureteral repair.

VerroTouch: High-Frequency Acceleration Feedback for Telerobotic Surgery

The Intuitive da Vinci system enables surgeons to see and manipulate structures deep within the body via tiny incisions. Though the robotic tools mimic ones hand motions, surgeons cannot feel what the tools are touching, a striking contrast to non-robotic techniques. We have developed a new method for partially restoring this lost sense of touch. Our VerroTouch system measures the vibrations caused by tool contact and immediately recreates them on the master handles for the surgeon to feel. This augmentation enables the surgeon to feel the texture of rough surfaces, the start and end of contact with manipulated objects, and other important tactile events. While it does not provide low frequency forces, we believe vibrotactile feedback will be highly useful for surgical task execution, a hypothesis we we will test in future work.