Priapism: pathophysiology and the role of the radiologist.

Priapism is defined as a penile erection that persists for 4 h or longer and is unrelated to sexual activity. Its identification is important as lack of timely treatment (particularly of the low flow/ischaemic subgroup) can result in persisting erectile dysfunction as a consequence of irreversible corporal fibrosis. This review describes the physiology and anatomy of the normal erection, the aetiology and pathophysiology of the different types of priapism, and the role of the radiologist in the management of the condition. The treatment of iatrogenic priapism following intracavernosal injection of pharmacostimulant is discussed.