There is no correlation between erectile dysfunction and dose to penile bulb and neurovascular bundles following...

We evaluated the relationship between the onset of erectile dysfunction and dose to the penile bulb and neurovascular bundles (NVBs) after real-time ultrasound-guided prostate brachytherapy.

One hundred forty-seven patients who underwent prostate brachytherapy met the following eligibility criteria: (1) treatment with 125I brachytherapy to a prescribed dose of 160 Gy with or without hormones without supplemental external beam radiation therapy, (2) identification as potent before the time of implantation based on a score of 2 or higher on the physician-assigned Mount Sinai Erectile Function Score and a score of 16 or higher on the abbreviated International Index of Erectile Function patient assessment, and (3) minimum follow-up of 12 months. Median follow-up was 25.7 months (range, 12-47 months).

The 3-year actuarial rate of impotence was 23% (34 of 147 patients). An additional 43% of potent patients (49 of 113 patients) were using a potency aid at last follow-up. The penile bulb volume receiving 100% of the prescription dose (V(100)) ranged from 0-0.05 cc (median, 0 cc), with a dose to the hottest 5% (D(5)) range of 12.5-97.9 Gy (median, 40.8 Gy). There was no correlation between penile bulb D(5) or V(100) and postimplantation impotency on actuarial analysis. For the combined right and left NVB structures, V(100) range was 0.3-5.1 cc (median, 1.8 cc), and V(150) range was 0-1.5 cc (median, 0.31 cc). There was no association between NVB V(100) or V(150) and postimplantation impotency on actuarial analysis.

Penile bulb doses are low after real-time ultrasound-guided prostate brachytherapy. We found no correlation between dose to either the penile bulb or NVBs and the development of postimplantation impotency.