Ablation of canine prostate using transurethral intraprostatic absolute ethanol injection

Objectives. Despite extensive research involving numerous treatments for be nign prostatic hyperplasia (BPH), the ideal modality has yet to be discover ed. This study evaluated chemoablation of the prostate using transurethral intraprostatic absolute ethanol injection (AEI) in an in vivo canine model. Methods. Eight mongrel dogs, 7 to 10 years old, underwent transurethral int raprostatic AEI with various ethanol volumes (10 to 26 mL/animal, mean 19.9 ). Injection was performed using a 20-gauge, passive deflection, hollow-cor e needle, introduced cystoscopically by way of a perineal urethrotomy. Oral antibiotics were administered perioperatively. Blood alcohol levels were d etermined. The canines were kept alive for 1 hour (n = 1), 7 days (n = 2), and 21 days (n = 5) after the treatment. The dogs were observed twice daily for a minimum of 50 minutes to determine continence. At least one spontane ous voiding was recorded at each observation. Before the dogs were sacrific ed, the prostate and surrounding tissues were harvested, with gross and mic roscopic examination performed by a single pathologist. Results. Seven and 21 days after AEI, the prostates demonstrated necrosis a nd cavity formation. Deep injection resulted in cavity formation in a subca psular location. Superficial injection resulted in cavity formation that wa s confluent with the urethra and resulted in a widened urethral lumen. No c omplications directly related to AEI were seen, and systemic absorption of ethanol was minimal Conclusions. AEI can effectively ablate prostatic tissue in canines with mi nimal systemic absorption. No disruption of the prostatic capsule or injury to the bladder urothelium and urethral sphincter was identified. Human stu dies of intraprostatic AEI for BPH adenomatous tissue chemoablation are ong oing at our institution. (C) 1999, Elsevier Science Inc.