A radiofrequency method of thermal tissue ablation for benign prostatic hyperplasia.

OBJECTIVES: To evaluate the safety, feasibility, and efficacy of transurethral ablative prostatectomy (TURAPY), a radiofrequency method of thermal tissue ablation of benign prostatic hyperplasia (BPH). METHODS: Twenty men, ages 55 to 81 years (mean, 67), with symptomatic BPH and with peak flow rate 12 mL/s or less, were treated with the TURAPY device (Direx Medical Systems). A 2 cm long heating element and 2 thermoprobes (for simultaneous prostatic temperature monitoring) are mounted on a Foley-like catheter and used for TURAPY treatment administration. This TURAPY catheter was modified by placing an extra set of thermoprobes in the sphincter region to allow sphincteric temperature monitoring. The treatment was administered at a maximum temperature of 70 degrees to 75 degrees C for 1 hour under local anesthesia as a day case. RESULTS: All 20 patients completed the treatment. The maximum recorded rectal temperature was 39.5 degrees C. The maximum sphincter temperature was not allowed to exceed 42 degrees C. The post-treatment morbidity included dysuria and minor urethral bleeding in 12 patients. Three patients developed urinary infection requiring antibiotic treatment. All 20 patients were followed up 3 months after treatment. The mean International Prostate Symptom Score (IPSS) improved from 19.4 to 6.2 (68%), the mean peak flow rate increased from 7.9 to 12.9 mL/s (63%), and the mean postvoid residue decreased from 222 to 81 mL (64%). Overall, 80% of patients exhibited at least a 50% improvement in either the IPSS or the peak flow rate. There was a mean reduction in prostatic volume measured by transrectal ultrasound of 14 mL (29% reduction). The subjective and objective improvements, in 8 patients followed up 6 months after treatment, have been maintained. There was extensive coagulative heat necrosis of periurethral tissue with sparing of subcapsular tissue in prostate biopsy specimens taken from 1 patient 5 days after treatment. There was endoscopic and sonographic evidence of canalization of the obstructed prostatic urethra 3 months after treatment. CONCLUSIONS: Treatment with the TURAPY device was found to be safe, feasible, and effective in improving both subjective and objective measurements of benign prostatic obstruction in this pilot study on 20 patients.

A preliminary investigation of temperature distribution in the prostatic urethra during Thermex II thermotherapy.

In a random group of five patients undergoing thermotherapy with Thermex II (Direx Systems), the temperature in the region of the external sphincter was measured using a modified Thermex catheter. In all five patients the measured temperature exceeded 44.5 degrees C for more than half the duration of treatment. Further temperature mapping studies and studies on the assessment of sphincter function after Thermex II thermotherapy are in progress.