Recently, a college student underwent urologic evaluation for erectile dysfunction (ED), and the urologist suggested that a “venous leak” might be causing the problem. Can you clarify?
— Thomas McGrath, MD, Storrs, Conn.
The physiology of erection is well-described in the eighth edition of Campbell’s Urology (Walsh PC, Retik AB, eds. Philadelphia, Pa.: WB Saunders; 2002: chap 45). In the flaccid state, the smooth muscles of the erectile tissue are tonically contracted. With sexual stimulation, neurotransmitters are released from the cavernous nerve terminals, resulting in relaxation of these smooth muscles. This is followed by arterial dilatation, sinusoidal relaxation (which traps incoming blood), and venous compression (which reduces venous outflow—thus the description of possible “venous leak” as an etiology for ED). Although a crucial part of the erectile cycle is veno-occlusion, there is no consensus that veno-occlusive surgery (removing veins outside the corpora cavernosa) is an effective therapy.
—David T. Noyes, MD (108-10)