Sonography of the penis/erectile dysfunction.

Erectile dysfunction (ED) is defined as the persistent inability to achieve and/or maintain an erection for a satisfactory sexual activity. It is secondary to several organic, psychogenic, and combined causes, and represents a serious health dilemma affecting both men and their partners. The diagnostic approach to erectile dysfunction has significantly changed in the last years with the advent of phosphodiesterase-5 (PDE5) inhibitors, and with the recognition that surgical treatment of both arterial insufficiency and penile venous leak have poor long-term clinical outcomes. Although imaging modalities have diminished in importance, differentiating among causes of erectile dysfunction remains mandatory in good medical practice, and ultrasound (US) still remains the cornerstone of the diagnostic workup. US provides an objective, minimally invasive evaluation of penile hemodynamics. Moreover, it provides an excellent depiction of the penile anatomy and of its changes in pathological conditions such as in patients with Peyronie's disease, priapism, and posttraumatic erectile dysfunction.