Diagnosis

Laboratory Tests

Blood Tests for Hormonal Abnormalities. Blood tests may be used to measure testosterone levels and, if necessary, prolactin levels to determine if there are hormone problems. The doctor may also screen for thyroid and adrenal gland dysfunction. In addition, various specific tests for erectile dysfunction can be performed.

Tests for Medical Conditions That May be Causing Erectile Dysfunction. Evidence of other medical conditions should be sought, particularly hypertension, diabetes, atherosclerosis, and nerve damage.

Monitoring Nighttime Erections

Tests that monitor nighttime erections may be used to determine if the causes of erectile dysfunction are more likely to be psychological. Neither of the following methods is helpful in determining a physical cause for erectile dysfunction.

Snap-Gauge Test. The snap-gauge test monitors the man's ability to achieve an erection during sleep. It is a very simple test.

• When the man goes to bed, he places bands around the shaft of his penis
• If one or more breaks during the course of the night, it provides evidence of an erection. In this case, a psychological basis for the erectile dysfunction is likely

RigiScan Monitor. A more sophisticated and expensive device is the RigiScan monitor, which makes repetitive measurements of rigidity around the base and tip of the penis. This test is quite accurate but may fail to detect mild cases of erectile dysfunction.

Penile Brachial Index

The penile brachial index is a measurement that compares blood pressure in the penis with the blood pressure taken in the arm. Problems with the arterial flow to the penis can be detected using this method.

Imaging Techniques

Imaging tests may be used in certain cases, but they are expensive and often limited to younger men. Anyone considering these tests should have them done in a specialized setting by professionals experienced in their use.

Dynamic Infusion Cavernosometry and Cavernosography. Dynamic infusion cavernosometry and cavernosography (DICC) is usually only given to young men in whom some blockage of the penis or physical injury of the pelvic area is suspected. After an erection is induced with drugs, the following four steps are taken: