Vascular Factors are Important in Recovery of Sexual Function

Erectile function in men is the end result of a series of tightly coupled events: nerve stimulation, diatlation of arteries, and constritions of veins. Therefore, during radical prostatectomy it is important to preserve nerve function where possible. However, despite nerve preservation, some patients are still impotent following radical prosatatectomy. This may be secondary to arterial or venous problems. Men who are older or who have a history of vascular disease, diabetes, or hypertension are more likely to have a restrictions in the arterial blood supply to the penis. Potentcy in these patients may be maintainted by small acessory blood vessels that surround the prostate. Interruption of these blood vessels may be responsible for impotence. (We can test for this; these patients will not respond to injections with papaverine, a drug that relaxes smooth muscle).

Another important cause of impotence is a condition known as venous leak. In these patients, although the nerves and arteries are intact, the blood does not collect in the spongy tissues of the penis because the veins no longer constrict normally. These men note that they may start to have an erection but loose it. Fortunately, there is a simple treatment that helps most patients. By placing a soft tourniquet at the base of the penis, e.g. a "ponytail holder" or rubber band, the blood is held in the penis and the erection is not lost.

The recovery of sexual function following radical prostatectomy may take up to two years and patients report that sexual function often improves for two or more years thereafter. During this interval, vacuum constriction devices and injections with pharacologically active agents such as papaverine, phentolamine, or prostaglandin-E₁ should provide erections sufficient for intercourse.