Experimental model of human corpus cavernosum smooth muscle relaxation.

PURPOSE: To describe a technique for en bloc harvesting of the corpus cavernosum, cavernous artery and urethra from transplant organ donors and contraction-relaxation experiments with corpus cavernosum smooth muscle. MATERIALS AND METHODS: The corpus cavernosum was dissected to the point of attachment with the crus penis. A 3 cm segment (corpus cavernosum and urethra) was isolated and placed in ice-cold sterile transportation buffer. Under magnification, the cavernous artery was dissected. Thus, 2 cm fragments of cavernous artery and corpus cavernosum were obtained. Strips measuring 3 x 3 x 8 mm(3) were then mounted vertically in an isolated organ bath device. Contractions were measured isometrically with a Narco-Biosystems force displacement transducer (model F-60, Narco-Biosystems, Houston, TX, USA) and recorded on a 4-channel Narco-Biosystems desk model polygraph. RESULTS: Phenylephrine (1 microM) was used to induce tonic contractions in the corpus cavernosum (3-5 g tension) and cavernous artery (0.5-1 g tension) until reaching a plateau. After precontraction, smooth muscle relaxants were used to produce relaxation-response curves (10(-12) M to 10(-4) M). Sodium nitroprusside was used as a relaxation control. CONCLUSION: The harvesting technique and the smooth muscle contraction-relaxation model described in this study were shown to be useful instruments in the search for new drugs for the treatment of human erectile dysfunction.

Experimental model of human corpus cavernosum smooth muscle relaxation

PURPOSE: To describe a technique for en bloc harvesting of the corpus cavernosum, cavernous artery and urethra from transplant organ donors and contraction-relaxation experiments with corpus cavernosum smooth muscle. MATERIALS AND METHODS: The corpus cavernosum was dissected to the point of attachment with the crus penis. A 3 cm segment (corpus cavernosum and urethra) was isolated and placed in ice-cold sterile transportation buffer. Under magnification, the cavernous artery was dissected. Thus, 2 cm fragments of cavernous artery and corpus cavernosum were obtained. Strips measuring 3 x 3 x 8 mm3 were then mounted vertically in an isolated organ bath device. Contractions were measured isometrically with a Narco-Biosystems force displacement transducer (model F-60, Narco-Biosystems, Houston, TX, USA) and recorded on a 4-channel Narco-Biosystems desk model polygraph. RESULTS: Phenylephrine (1µM) was used to induce tonic contractions in the corpus cavernosum (3 - 5 g tension) and cavernous artery (0.5 - 1g tension) until reaching a plateau. After precontraction, smooth muscle relaxants were used to produce relaxation-response curves (10-12M to 10-4 M). Sodium nitroprusside was used as a relaxation control. CONCLUSION: The harvesting technique and the smooth muscle contraction-relaxation model described in this study were shown to be useful instruments in the search for new drugs for the treatment of human erectile dysfunction.

Laparoscopic-assisted radical cystectomy with U-shaped orthotopic ileal neobladder constructed using nonabsorbable titanium staples.

INTRODUCTION: Recently, nonabsorbable staples have been safely used in a variety of urologic open and laparoscopic extirpative and reconstructive procedures. We report the surgical steps of our technique of U-shaped orthotopic ileal neobladder created with titanium staples. TECHNICAL CONSIDERATIONS: Using stay stitches, a 45 to 50-cm ileal segment is arranged in a U shape with two segments of approximately 20 cm and an afferent limb of 5 or 10 cm. An opening is made at the lowest point of the U-ileal segment on its antimesenteric border. The jaws of the 80 x 3.5-mm nonabsorbable mechanical stapler are accommodated within the bowel loop and fired twice, bringing together and detubularizing approximately 15 cm of each arm of the U. To complete the pouch detubularization, another small opening is made at the bottom of the chimney on its medial border. After this, a third nonabsorbable mechanical stapler had its jaws introduced through this opening and through the open end of the bowel segment on the right side and the stapler is fired, completing the U pouch. Subsequently, the open ends of the U segment and the opening made at the base of the afferent limb are closed with absorbable running sutures. CONCLUSIONS: Our technique is feasible and may represent an alternative to expand the spectrum of continent urinary reservoirs that could be expeditiously created with nonabsorbable staples. Continued surveillance is mandatory to determine the lithiasis-inducing potential of these titanium staples within the urinary tract.

Stapleless laparoscopic assisted radical cystectomy with ileal neobladder in a male and with ileal loop in a female: initial report from Brazil.

INTRODUCTION: Here, we report our initial experience with laparoscopic assisted radical cystectomy without the use of surgical staples. CASES REPORT: A 70 year old male and a 55 year old female were diagnosed to have T2G3 transitional cell carcinoma of the bladder with negative metastatic work-out. Both patients were scheduled and agreed to a laparoscopic assisted radical cystectomy. In both cases, urinary diversion (orthotopic ileal Studer neobladder in the male and ileal conduit in the female) was performed extracorporeally following radical cystectomy. In both cases control of the bladder vascular pedicle was accomplished with a combination of metallic and hem-o-lock clips. The total surgical time was 6.5 hours in both cases. Estimated intra-operative blood loss was 500 cc and 350 cc respectively, however both patients required postoperative blood transfusions. No intraoperative complications occurred. In both cases, pathology revealed negative surgical margins. CONCLUSIONS: Extracorporeal creation of urinary diversion decrease the overall operative time. Laparoscopic pelvic lymphadenectomy can be performed following the extended template. The use of surgical clips instead of vascular Endo-GIA titanium staples to control the bladder vascular pedicles is feasible and safe in selected patients, thus reducing intraoperative surgical costs. Considerable experience with laparoscopic radical prostatectomy is necessary before one attempts laparoscopic radical cystectomy.

Stapleless laparoscopic assisted radical cystectomy with ileal neobladder in a male and with ileal loop in a female: initial report from Brazil

INTRODUCTION: Here, we report our initial experience with laparoscopic assisted radical cystectomy without the use of surgical staples. CASES REPORT: A 70 year old male and a 55 year old female were diagnosed to have T2G3 transitional cell carcinoma of the bladder with negative metastatic work-out. both patients were scheduled and agreed to a laparoscopic assisted radical cystectomy. In both cases, urinary diversion (orthotopic ileal Studer neobladder in the male and ileal conduit in the female) was performed extracorporeally following radical cystectomy. In both cases control of the bladder vascular pediclewas accomplished with a combination of metallic and hem-o-lock clips. The total surgical time was 6.5 hours in both cases. Estimated intra-operative blood loss was 500 cc and 350 cc respectively, however both patients required postoperative blood transfusions. No intraoperative complications occurred. In both cases, pathology revealed negative surgical margins. CONCLUSIONS: Extracorporeal creation of urinary diversion decrease the overall operative time. Laparoscopic pelvic lymphadenectomy can be performed following the extended template. The use of surgical clips instead of vascular Endo-GIA titanium staples to control the bladder vascular pedicles is feasible and safe in selected patients, thus reducing intraoperative surgical costs. Considerable experience with laparoscopic radical prostatectomy is necessary before one attempts laparoscopic radical cystectomy.