Laser investigations of the strictured dog urethra.

The effects of the Neodymium:YAG laser beam on normal as well as on granulation tissue of the dog urethra were investigated in vitro. To determine the effectiveness of the laser beam special attention was paid to the size of the local spot and the pulse duration. After determination of the most favorable diameter of the focus and the pulse duration of the laser beam, endoscopic laser examinations were performed on normal and experimentally strictured urethrae in dogs. A suitable laser endoscope was designed and a surgical technique for laser-beam treatment of the strictured urethra was developed. The postoperative follow-up period was up to 6 weeks. There was no need for postoperative urinary diversion. Neither bleeding nor perforations were observed.