1015 Greenlight PVP: Safety and efficacy in large prostates >100ml

Photoselective vaporization of the prostate with the potassium-titanyl-phosphate laser in men with prostates of >100 mL

OBJECTIVES

To assess the efficacy of photoselective vaporization of the prostate (PVP) in men with prostates of >100 mL and causing bladder outlet obstruction (BOO), using the high-power 80 W potassium-titanyl-phosphate laser (GreenLight PV, Laserscope, San Jose, CA, USA), which offers rapid tissue ablation with minimal bleeding.

PATIENTS AND METHODS

We assessed 54 consecutive patients with prostates of >100 mL (mean 135, SD 42, range 100-300) who had PVP between May 2003 and August 2005. Evaluations before PVP included urine flowmetry, the International Prostate Symptom Score (IPSS), a quality-of life (QoL) score, prostate-specific antigen (PSA) level, and prostate volume measured by transrectal ultrasonography (TRUS).

RESULTS

The mean (SD, range) duration of PVP was 81.6 (22.9, 39-150) min, the mean energy used for PVP was 278 (60, 176-443) kJ and the mean duration of catheterization after PVP was 23.0 (17.1, 0-72) h. The mean (sd) maximum urinary flow rate improved from 8.0 (3.1) to 18.2 (8.1), 18.5 (9.2), 17.9 (7.8) and 19.3 (9.8) mL/s at 3, 6, 12 and 24 months, respectively. The IPSS and QoL scores showed similar improvements, and there was a statistically significant reduction in PSA level and prostate volume after PVP. There was no major complication and no patient had transurethral resection syndrome or a blood transfusion.

CONCLUSIONS

The 80 W KTP laser PVP offers rapid tissue ablation in patients with BOO caused by a large prostate. The short- and medium-term outcomes show that this technique can be a viable alternative to open prostatectomy.

Use of expired breath ethanol measurements in evaluation of irrigant absorption during high-power potassium titanyl phosphate laser vaporization of prostate

OBJECTIVES

To evaluate formally the risk and levels of irrigant absorption during high-power potassium titanyl phosphate (KTP) laser vaporization of the prostate by the Greenlight PV system using the expired breath ethanol technique.

METHODS

Forty consecutive patients underwent laser vaporization of the prostate. Of these patients, 17 had a preoperative transrectal ultrasound estimation of the prostate volume (mean 97 cm3). All procedures were performed under general anesthesia, by either of two consultants or a trainee. A 1% ethanol solution was used as irrigation fluid. Throughout the operation, the expired breath was analyzed for ethanol using a standard alcometer "plumbed" into the anesthetic circuit. Venous blood samples were taken immediately before and after the procedure for measurements of serum sodium and plasma alcohol levels.

RESULTS

On average, 155,000 J of laser energy was delivered in 47 minutes. In all patients and on all occasions, the expired breath ethanol remained at 0. No statistically significant change was found in the serum sodium concentration during the procedure (P = 0.42), and no patient displayed any clinical evidence of transurethral resection syndrome.

CONCLUSIONS

The results of this study have confirmed, for the first time, the lack of significant absorption of irrigation fluid during high-power KTP vaporization of the prostate using a recognized sensitive technique and the safety of using sterile water as that irrigant. This was the case even in those patients with very large prostates who are usually considered at high risk of experiencing the clinical consequences of fluid absorption during transurethral resection of the prostate and regardless of the experience of the surgeon.