U. Engelmann

Vasectomy reversal in central Europe: results of a questionnaire of urologists in Austria, Germany and Switzerland

A detailed questionnaire was sent to urologists in Austria, Switzerland and West Germany on the frequency of contraceptive vasectomies, vasectomy reversal, technique and success rates. The response rate was 859 of 2,137 (40.2%). The rate of annual contraceptive vasectomies averaged 28,519 or 378 vasectomies per million inhabitants. The rate of vasovasostomies and vasoepididymostomies was 8.3 and 3.8 procedures per million inhabitants, respectively. A macroscopic technique was used by 9.5% of the responding urologists, loupes were used by 58.5% and an operating microscope by 32%. The majority (74.1%) preferred a 1-layer technique and an unstented anastomosis (84.4%). The average patency and pregnancy rates were 73 and 47%, respectively, for vasovasostomy and 45 and 18%, respectively, for vasoepididymostomy. A total of 78 alloplastic spermatoceles was reported, with detection of motile spermatozoa in 19 and pregnancy in 1.

Laser welded vascular anastomosis

SummaryA comparative study was undertaken to investigate the application of a specially adapted microsurgical Neodymium Yag Laser system with a wavelength of 1,319 μm and a CO2 laser system for laser assisted microvascular end-to-end anastomosis (LAMA) of the rat femoral artery. Conventionally sutured anastomoses served as controls. Postoperative investigations included patency tests, light microscopy and tensile strength measurements. Both laser systems seem to be equally suitable for LAMA: The patency rates do not differ from those of sutured anstomoses and formation of microscopically small aneurysms occurred predominantly in control animals and only once in laser groups. The clamp time needed for LAMA was half the time that was needed for sutured anastomoses. Wound healing in all groups was similar with less fibrotic reactions and less foreign body granulomas in laser groups. At all intervals tensile strength was significantly higher for sutured anastomoses while differences between the CO2- and the ND: Yag-laser groups were not statistically significant. Potential applications in urology include microvascular anastomoses in erectile dysfunction, pediatric and reconstructive urology.

Microsurgical arteriovenous revascularization in the treatment of vasculogenic impotence

We studied 35 patients with vasculogenic impotence who underwent an operation since 1986 and who were followed postoperatively for a minimum of 1.5 years. In all patients a microsurgical anastomosis was performed between the inferior epigastric artery and the arteriovenous shunt of the dorsal penile vessels. Potency was restored or improved in 77% of the patients during the long-term observation. Doppler or duplex sonography confirmed the same percentage of patent anastomoses. Through microsurgical modifications of the Hauri procedure and the interposition of free venous grafts, it was possible to operate further in 3 patients with short epigastric arteries and to treat intraoperative complications effectively in 1.

Laser Assisted Urethral Closure in the Rat: Comparison of CO2 and Neodymium-YAG Laser Techniques

In 65 male rats a comparative study was undertaken to investigate a Neodymium-YAG and CO2 laser system for the microsurgical repair of longitudinal incisions of the rat urethra. Postoperative investigations included patency tests, necropsy and light microscopy. Use of the laser systems did not reduce operation time. The highest rate of postoperative strictures (90%), urethral fistulas (30%), urinomas (20%) and postoperative deaths (70%) was seen in the Neodymium-YAG laser group. CO2 laser repair was almost as efficacious as microsuture repair, except for a higher rate of urethral fistulas resulting from the initially weak laser weld. Based on these findings, the Neodymium-YAG laser seems unsuitable for urethral repair. Further studies in larger animals are warranted using a CO2 laser in combination with postoperative cystostomy for urinary diversion in order to avoid fistulas in the early postoperative period.

Laser-Assisted Vasovasostomy in the Rat

A comparative study was undertaken to investigate the Nd:YAG and CO2 laser systems for laser-assisted vasovasostomies (LAVs). In 32 rats 64 vasovasostomies were performed, either conventionally sutured (CSV) or laser-welded (LAV-CO2 and LAV-Nd:YAG). Postoperative investigations included patency tests, gross examination, light and electron microscopy. The highest rate of sperm granulomas (50%) and the lowest patency rate (50%) was seen in the LAV-Nd:YAG group. LAV-CO2 showed the lowest rate of sperm granulomas (12.5%) and had a patency rate (82%) which was comparable to that of CSV (88%). Laser-assisted vas anastomosis is time saving and technically easy to perform. Contrary to microvascular anastomoses, where both laser types offer the same results, vas anastomosis is better done using a CO2 laser system.

CO2 and Nd:YAG laser systems in microsurgical venous anastomoses

SummaryA comparative study was undertaken in 81 rats to investigate a CO2 and Nd:YAG laser system for laserwelded anastomosis of the femoral vein. Conventionally sutured anastomoses (CMSA) served as controls. Laserwelded anastomosis (LAMA) was easier and could be performed 30% faster than CMSA. Postoperative investigations included patency tests, postmortem examinations and light and electron microscopy. Aneurysms were not seen. Foreign-body reaction was more pronounced in CMSA. Patency rates for CO2-LAMA and CMSA were equal, whereas Nd:YAG-LAMA resulted in significantly higher rate of early postoperative thrombosis (P<0.01). Because of its physical properties, the CO2-laser system seems to be better suited for laser welding of delicate structures such as the rat femoral vein.

Sex-Dependent Urolithiasis in the Portacaval Shunt Rat

The portocaval shunt rat represents an interesting experimental model of endogenous stone formation.

Bursting Strength of the Rat Aorta: Comparison of Suture and Laser Anastomoses

The bursting strength of sutured and laser-welded vascular anastomoses were assessed in a rat aorta model. Postoperative investigations included postmortems, light and scanning electron microscopy and measurements of bursting strength at set intervals (30 min, 3, 14 and 28 days postoperatively, p.o.). Laser-bonded anastomoses consistently demonstrated lower bursting strengths than suture controls, with statistically significant differences at 30 min and 3 days p.o. (p less than 0.01). Laser anastomosis was easier and faster to perform, the foreign body reaction was markedly lower than in sutured controls. Formation of aneurysms was not observed.