Canine Transurethral Laser-Induced Prostatectomy

Abstract

We report our experience with ultrasound-guided transurethral laser-induced prostatectomy (TULIP) in a canine model. The device used is composed of a 22F plastic sheath with a 36F low-pressure balloon at the distal end. A probe containing a 7.5-MHz ultrasonic sector transducer and a 90° angled laser port is placed inside the sheath, which is passed into the prostatic urethra. The balloon is inflated in this area. Neodymium:yttriumaluminum-garnet (Nd:YAG) laser energy, 25 W or 35 W, is directed at four quadrants in the prostatic urethra using ultrasonic guidance. The operator uses a spring-loaded handle grip to pull the laser through the prostatic urethra at a specific rate. Twelve adult male fox hounds, 5 to 7 years old, received laser treatments, and groups of four animals were humanely sacrificed 3,7, and 12 weeks after therapy. A control animal was euthanized at 7 weeks and one at 12 weeks after undergoing a sham procedure. Light microscopic analysis of the laser-treated prostates demonstrated glandular atrophy and near-complete re-epithelialization at 3 weeks and glandular atrophy, mild chronic inflammation, and complete re-epithelialization at 7 and 12 weeks. The prostates of the control animals had areas of mild chronic inflammation but no glandular atrophy. Defects in the prostatic urethra similar to those found after transurethral prostatectomy (TURP) were present in the laser-treated animals but were absent in the controls. This technology may prove to be a reasonable alternative to TURP.