Low-power v high-power KTP laser: improved method of laser ablation of prostate

Abstract

Background and objective: Current treatment technique for laser prostatectomy involve Nd:YAG wavelength at 60 to 80 W. Use of the KTP wavelength in addition to Nd:YAG allows for vaporization of more tissue, decreasing the amount undergoing coagulation necrosis. In this study, we compared 20 W and 40 W of KTP laser energy in conjunction with the Nd:YAG wavelength for the treatment of benign prostatic hyperplasia (BPH).

Patients and materials: A total of 50 consecutive patients underwent laser ablation of the prostate, with 38 patients (Group I) receiving treatment with 20 W of the KTP and 60 W of the Nd:YAG wavelengths. The other 12 patients (Group II) underwent treatment with 40 W of KTP and 60 W of Nd:YAG laser energy. The patients had an initial evaluation consisting of American Urological Association (AUA) Symptom Score, uroflowmetry, transrectal ultrasonography for prostate volume measurement, and assay of prostate specific antigen (PSA) serum level. The patients were seen in follow-up at 1, 3, and 6 months.

Results: The mean symptom score decreased from 23.4 to 8.9 from Group I and from 18.2 to 3.5 for Group II at the 6-month follow-up. The mean peak urinary flow rate increased from 8.4 to 15.4 mL/sec Group I and from 8.3 to 16.5 mL/sec in Group II at the 6-month follow-up.

Conclusions: The patients treated with the 40 W of KTP laser energy experienced a more rapid and sustained improvement in symptom score than those treated at 20 W. The improvement in peak urinary flow rate was approximately the same in the two groups.