[Photoselective vaporization of the prostate (PVP) using 80 watt high power potassium-titanyl-phosphate (KTP) laser for benign prostatic hyperplasia: the first fifty-seven patients in Japan]

Abstract

Objective: To assess the safety and efficacy of photoselective vaporization of the prostate (PVP) using 80 watt high power potassium-titanyl-phosphate (KTP) laser for benign prostatic hyperplasia (BPH).

Methods: Fifty-seven patients with lower urinary tract symptoms secondary to benign prostatic hyperplasia underwent 80 W KTP laser vaporization of the prostate. According to their International Prostate Symptom Score Index (IPSS) and Quality of life (QOL) score as well as measurements of their peak flow rate and postvoiding residual urine volume (RUV), they fulfilled the diagnostic criteria of BPH. Vaporization was performed with the GreenLight PV ADDStat fiber, which was inserted through a 22.5Fr. continuous flow laser cystoscope, and a saline solution was used for irrigation. KTP laser energy was generated by a GreenLight PV (Minnetonka, Minnesota) generator. The end point of the procedure was to create a cavity like in TURP. Once vaporization was completed, an18Fr Foley catheter was inserted and was removed the next morning, as a rule. Patients were evaluated preoperatively, and at 2 weeks and 1, 3 and 6 months postoperatively.

Results: The procedure could be performed without any intraoperative complication. None of the patients required continuous bladder irrigation or blood transfusion postoperatively. The mean age was 71.0 +/- 8.3 years (range 52 to 86). The preoperative prostate volume was 41.0 +/- 24.9 (mean +/- SD, range 6.7 to 107.2) and the preoperative serum PSA was 4.5 +/- 4.1 ng/ml. Preoperative and immediate postoperative serum sodium concentration was 141.9 +/- 1.8 mEq/L and 142.2 +/- 1.8 mEq/L, respectively (p = 0.23). The hemoglobin value changed from 14.0 +/- 1.4 mg/dl preoperatively to 13.4 +/- 1.4 mg/dl postoperatively. The operating time was 68.3 +/- 35.0 minutes (range 21 to 170) and total laser energy was 171.1 +/- 80.3 kJ (range 18.1 to 484.8). The catheter indwelling time was 18.6 +/- 3.3 hrs (range 15 to 48). At 2 weeks and 1, 3 and 6 months the International Prostate Symptom Score decreased from 20.2 +/- 8.9 to 11.4 +/- 7.8, 9.3 +/- 6.0, 6.6 +/- 5.0 and 6.1 +/- 5.0, respectively. The maximum urinary flow increased from 7.2 +/- 2.9 mL/s to 13.6 +/- 7.6, 12.2 +/- 6.1, 15.3 +/- 7.4, and 15.3 +/- 7.5 mL/s, respectively.

Conclusions: Photoselective vaporization of the prostate (PVP) using the high power (80 W) potassium-titanyl-phosphate laser for benign prostatic hyperplasia (BPH) proved to be an effective and safe procedure for our patients.