Changes in Penile Morphometrics in Men with Erectile Dysfunction after Nerve-Sparing Radical Retropubic Prostatectomy

Area of Science:

• Urology
• Andrology
• Surgical Oncology

Background:

• Anecdotal reports suggest penile size reduction in men with erectile dysfunction (ED) post-nerve-sparing radical retropubic prostatectomy (NSRRP).
• Understanding postoperative penile changes is crucial for patient counseling and managing sexual health after prostate cancer treatment.

Purpose of the Study:

• To objectively quantify changes in penile size (length and circumference) in men with ED following NSRRP.
• To compare sexual function inventory scores of men with post-NSRRP ED to control groups.

Main Methods:

• Penile measurements (flaccid and erect length/circumference) were taken from 100 men with ED post-NSRRP.
• Erections were induced via intracorporeal Trimix injections.
• Sexual function was assessed using a validated inventory and compared to age-matched controls.

Main Results:

• A significant decrease in penile dimensions was observed post-NSRRP, with an 8-9% reduction in length and circumference.
• The most pronounced penile volume changes (19-22%) occurred between 4 and 8 months postoperatively.
• Men with post-NSRRP ED reported more severe ED but better libido compared to men with ED from other causes.

Conclusions:

• Nerve-sparing radical retropubic prostatectomy is associated with a significant decrease in penile size in men with ED.
• Potential etiologies include denervation, smooth muscle atrophy, apoptosis, or hypoxia-induced damage to the corpora cavernosa.
• Further research is warranted to fully understand the mechanisms behind these postoperative penile alterations.