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Ran Katz

Publications and source records attributed to Ran Katz.

23 records · Page 2Linked to original sources

Laparoscopic radical prostatectomy: description of the extraperitoneal approach using the da Vinci robotic system.

PURPOSE: We developed and assessed the feasibility of extraperitoneal laparoscopic radical prostatectomy performed using the da Vinci (Intuitive Surgical, Mountain View, California) robotic system. MATERIALS AND METHODS: In June 2002, 4 consecutive patients with clinically localized prostate cancer underwent extraperitoneal, robotic assisted laparoscopic radical prostatectomy. After development of the extraperitoneal space the surgeon performed laparoscopic prostatectomy from the remote control unit. The assistant aligned and exchanged robotic instruments and used conventional laparoscopic instruments to facilitate prostatectomy. Perioperative data and pathological results were recorded. RESULTS: No difficulties were noted when developing the extraperitoneal space. All additional steps were successfully performed with telerobotics. More distal placement of the robotic ports appeared to improve the feasibility of the extraperitoneal approach. The peritoneum acted as a natural bowel retractor and the distal port placement facilitated use of the assistant ports. Mean operative time was 274 minutes (range 124 to 360). Mean catheterization time and hospital stay were 2.7 and 5.3 days, respectively. A positive margin was observed in 1 patient and pathological stage was pT2 in 3 and pT3 in 1. No postoperative complications or open conversions were observed. CONCLUSIONS: The extraperitoneal approach was feasible with the da Vinci robotic system. Distal port placement for the robot appeared to create an ergonomic environment for the surgeon and assistant and more direct prostatic access. While additional clinical experience is required, the extraperitoneal approach may ultimately provide advantages for robotic and nonrobotic laparoscopic radical prostatectomy.

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Cadaveric versus porcine models in urological laparoscopic training.

INTRODUCTION: Laparoscopy performed on anesthetized pigs is an established training model. In this pilot study, we performed laparoscopy on cadavers as a training modality for urologists participating in a laparoscopic seminar. MATERIALS AND METHODS: We compared data from two consecutive laparoscopy seminars performed at our institution. The first included a laparoscopy session performed on pigs. The second was in the same setup, yet laparoscopy was performed on fresh cadavers. We analyzed and compared the trainees' perspectives regarding the 2 modalities using a 5-scale satisfaction questionnaire. RESULTS: Seven trainees attended the cadaveric and 9 the porcine laparoscopy session. The two groups were similar in terms of age and previous laparoscopic and urological experience. The general satisfaction of the two training modalities was high in the two groups, as well as their will for another session of the same kind. Yet the trainees ranked their understanding of the surgical anatomy, laparoscopic technique and use of instruments significantly higher in the cadaveric laparoscopy group (p values were 0.007, 0.006 and 0.032, respectively). CONCLUSIONS: Cadaveric laparoscopy may offer an ideal surgical environment allowing dissection and performance of complete procedures. In this pilot study, we conducted the first reported cadaveric laparoscopy training seminar in urology. The trainees preferred the cadaveric laparoscopy and found it superior to porcine laparoscopy. We believe that cadaveric laparoscopy is an important training tool, which may be added to the armamentarium of urological laparoscopy training courses.

Adult↗

Patient reported sexual function following laparoscopic radical prostatectomy.

PURPOSE: We evaluated the sexual function of patients who underwent laparoscopic radical prostatectomy. We assessed the effect of unilateral or bilateral preservation of the neurovascular bundle on the ability to achieve erections and have sexual intercourse postoperatively. MATERIAL AND METHODS: Between May 1998 and September 2001, 232 men underwent laparoscopic radical prostatectomy for localized prostate cancer at our institution. Sexual function questionnaires were given to the patients preoperatively. The study included 143 patients who were potent preoperatively. After the procedure the surgeon noted whether he performed unilateral, bilateral or no nerve sparing. Sexual function questionnaires were collected at 1, 3, 6 and 12 months after surgery. RESULTS: Of the 143 patients, 100, 80, 48 and 26 responded to the questionnaire at 1, 3, 6 and 12 months respectively. Of the nonnerve sparing group 11.7%, 11.1%, 16.6% and 30%, of the unilateral nerve sparing group 20%, 35%, 41.6% and 50% and of the bilateral nerve sparing group 32.5%, 41.1%, 29.1% and 87.5% respectively reported spontaneous erections 1, 3, 6 and 12 months after surgery, respectively. The overall incidence of positive lateral surgical margins in pT2 cases treated with a nerve sparing procedure was 8.4%. CONCLUSIONS: The overall rate of patients who had erections preoperatively and maintained erections after surgery (53.8%) is comparable to the results for open surgery. Patients with bilateral preservation did better than those with unilateral preservation. Our preliminary results show a promising rate of potency at 1 year after laparoscopic radical prostatectomy.

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Primary and postoperative retroperitoneal fibrosis-experience with 18 cases.

OBJECTIVES: Retroperitoneal fibrosis (RPF) is an uncommon disease complicated by ureteral entrapment. Its etiology includes several medications, periaortic inflammation, abdominal and retroperitoneal operations, radiotherapy, and malignancy. We present 18 patients, 14 of whom developed RPF after surgery and radiotherapy. METHODS: During the past 12 years, we treated 7 women and 11 men. The diagnosis was based on intravenous urography, retrograde pyelography, and computed tomography features. Computed tomography-guided or intraoperative biopsies were taken to differentiate benign from malignant fibrosis. In all patients, percutaneous stent nephrostomies or internal stents were inserted before surgery. The operation included ureterolysis with an omental flap or ureteral reimplantation. Follow-up included renal function tests, intravenous urography, and computed tomography. RESULTS: The mean patient age was 57.3 years (range 36 to 85). Fourteen patients developed RPF after abdominal or retroperitoneal surgery. Three had primary RPF and one malignant RPF due to metastatic disease. Six patients also underwent radiotherapy. The mean time between the insults to the diagnosis of RPF was 18.6 months (range 1 to 96). Ten patients had bilateral obstruction. Fourteen patients underwent surgery and four were treated with stenting only. Of the 14 patients who underwent surgery, 10 had a normal intravenous urogram postoperatively and 4 had decreased function of the formerly obstructed kidney. In 1 patient, re-entrapment of the ureter appeared owing to pelvic recurrence of tumor. At last follow-up, 1 patient waits with stents. The mean follow-up time was 22 months (range 4 to 52). CONCLUSIONS: The etiology of RPF varies. The unique feature of our series was the high incidence of patients who developed RPF after surgery and radiotherapy to the retroperitoneum. Nephrostomy drainage and ureteral stenting facilitated surgery. Ureterolysis combined with wrapping the ureter with an omental flap or re-implantation ensured good anatomic and functional results.

Adult↗

Urinary continence and erectile function: a prospective evaluation of functional results after radical laparoscopic prostatectomy.

OBJECTIVES: To evaluate prospectively functional results (urinary continence and erectile function) after laparoscopic radical prostatectomy. METHODS: From 1998 to 2001, 235 patients underwent laparoscopic radical prostatectomy for localized prostate cancer. All of them completed a confidential, self-administered questionnaire regarding urinary continence and erectile function before, and 1, 3, 6, and 12 months after surgery. Results were analyzed separately for day and night for urinary continence and status of neurovascular bundles as well as age for erectile function. RESULTS: To date, 100 consecutive patients have completed all questionnaires. Diurnal and nocturnal urinary continence have increased to 90% and 97% one year after surgery. Overall, 49.3% of the 77 patients, who were potent preoperatively, and did not receive any form of adjuvant therapy, had erections sufficient for intercourse one year after surgery. Potency rates were 38.4%, 53.8% and 58.8% after no, unilateral, and bilateral nerve bundle preservation, respectively. For younger patients (<60 years) with unilateral and bilateral neurovascular bundle preservation, potency rates were 75% and 83.3%, respectively. CONCLUSION: One year after laparoscopic radical prostatectomy, urinary continence rate is 90% during the day and 97% during the night. Overall potency rates after bilateral preservation of neurovascular bundles are 58.8% and 83.8% for the subgroup of younger patients (<60 years).

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