Venous leakage tests

There are a substantial number of men with organic ED, especially in the over-50 group, whose primary problem is a leak from the penile venous system during erections. For these men, blood flows through the penile veins at such a rate that not enough blood is trapped within the penis to cause engorgement and erection. It is now believed that the majority of venous leakage cases are associated with incomplete relaxation of the cavernous smooth muscle due to smooth muscle disease (diabetes, hypertension, high cholesterol, etc.), psychogenic sexual dysfunction, or weakening of the tunica; more rarely, a leak may be congenital or acquired. Increased inflow through the arteries and decreased outflow through the veins are necessary to develop and sustain a rigid erection.

A venous leak can be demonstrated, or even strongly suspected, if, during a natural erection or following an intracorporeal vasodilator injection, it becomes difficult to maintain the erection by continuous infusion of saline solution into the corpora. If the erection cannot be maintained with a small volume of infusion, or if the intracorporeal pressure drops rapidly and the erection is lost when the infusion is stopped, a venous leak is likely. A cavernosography, in which dye is injected into the corpora cavernosa to visualize the vasculature, may show the leaking vessels.

During testing for venous leakage, it is important to ensure that the smooth muscles of the corpora are completely relaxed, with a full erection, to avoid a false-positive result. There is still no consensus on established techniques, standards, and data norms for these tests, so their results should be cautiously interpreted. Furthermore, injection of hyperosmolar (highly concentrated) contrast material may cause severe corporal inflammation and scarring, possibly even leading to ED.

The identification of such a leak and its subsequent surgical repair could yield minimal success in a few selected cases, although results have been disappointing in the majority of cases on long-term follow-up. If the site and extent of a venous leak can be found, it can be treated by perineal exercises, intrapenile injections, constrictive rings, or vacuum devices. It can also be treated surgically by ligating the abnormal vessels, or by sclerotherapy, which consists of injecting sclerosing solutions into the abnormal veins to scar and obstruct them.

The success rate is, however, very low for most of these methods: in the vicinity of about 20% to 30%, which may, in selected rare cases, reach about 50% to 60%, depending on the veins and procedures involved. Surgery for venous leakage has been largely abandoned and is very seldom performed, especially because such leaks are generally attributed nowadays to diseased corporeal tissue and an inability of the vascular sinuses to dilate properly for normal obstruction of the leaking veins.