Laser Ablation Of Prostate Research Articles

New device for visual neodymium:YAG laser prostate ablation: acute and chronic canine evaluation.

This canine study (n = 6) evaluated the acute and chronic effects of Nd:YAG laser prostatectomy using a Prolase II fiber. The Prolase II device consists of a 1,000 microns quartz fiber which directs a cone of Nd:YAG laser energy, at 45 degrees to the axis of the fiber, into the prostatic urethra under direct visual guidance [visual laser ablation of prostate, (VLAP)]. Under visual guidance and saline irrigation, 60 seconds of 60 watts of laser power was delivered at 3, 6, 9, and 12 o'clock positions (14,400 J). One canine was instrumented but received no laser energy (control). One prostate was harvested acutely. The remaining four laser-treated dogs were evaluated at 6 to 16 weeks. The histopathology of acute laser effects shows areas of necrosis with loss of glandular structures and stromal edema. Surrounding this area was a zone of degenerative glandular structures extending up to 12.6 mm into the prostate. Two of the four dogs developed urinary retention at 6.5 and 9 weeks. On examination, both were found to have fibrotic strictures at the distal prostatic urethra with markedly dilated proximal prostatic urethral lumens (1.98 and 2.8 cm). Two other dogs showed no signs of urinary retention at sacrifice. Histopathology, both the 6 and 16 week laser-treated animals without urinary retention demonstrated dilated prostatic urethras with maximum cross-sectional diameters of 1.52 and 1.50 cm, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Serial endoscopy following visual laser ablation of prostate (VLAP)

Visual laser ablation of the prostate (VLAP) was evaluated by serial video-endoscopy and six months of clinical correlation in 7 men suffering from advanced prostatism and urinary retention. Images of the prostatic urethra were obtained before and at various intervals from two to nineteen weeks after the procedure. A substantial tissue defect evolved within three months; complete healing required an even longer period. Except in the 1 patient with middle lobe obstruction, spontaneous urination was restored in all patients (including 2 cancer patients additionally treated with androgen deprivation). No operative complications were encountered. Thus, a safe and visually successful prostatectomy was the usual result of VLAP in the present patients. As a minimally invasive method to remove an obstructing prostate, laser treatment warrants further study.