Duplex ultrasound is used in erectile dysfunction to visualize the normal structure of the penis and the blood flow in the vessels of it. It also evaluates the thickening of the vessels (atherosclerosis),calcifications if any. It is also used therapeutically to inject injections and to estimate the effect of the drug by measuring the diameter of the dilated vessels in the penis. It has no side effects as it has no radiation issues. It can be used in any patient of any age to diagnose the condition and to rule out any abnormalities.

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