Physician Interview
The physician typically interviews the patient about many physical and psychologic factors. The patient must be as frank as possible for his physician to make a diagnosis. He should not interpret these questions as intrusive or too personal if he expects to obtain help. These questions are very relevant and important for determining the proper approach. Even when erectile dysfunction has a clear physical cause, relationships and psychological factors can also have an effect.

Medical and Personal History. The physician should take a medical and personal history and may ask about the following:

 
• Past and present medical problems.  
• Medications or drugs being used.  
• Any history of psychological problems, including stress, anxiety, or depression.

Sexual History. In addition the physician will ask about the patient’s sexually history, which may include the following:

 
• The nature of the onset of the dysfunction.  
• The frequency, quality, and duration of any erections, and whether they occur at night or in the morning.  
• The specific circumstances when erectile dysfunction occurred.  
• Details of technique.  
• The patient’s motivation for and expectations of treatment.  
• Whether problems exist in the current relationship.

Interviewing the Sexual Partner. If appropriate, the physician might also interview the sexual partner. In fact, including the partner in the interview process may help the physician to better decipher underlying causes and in turn better recommend treatment choices.

Physical Examination
The physician should perform a careful physical exam, including examination of the genital area and a digital rectal examination (the doctor inserts a gloved and lubricated finger into the patient’s rectum) to check for prostate abnormalities.

Trials Using Erectile Function Treatments
Physicians now usually recommend a trial of sildenafil (Viagra) to test for an erection response. This often can replace more invasive and expensive tests, such as an injection of papaverine or prostaglandin E1, medications that dilate blood vessels in the penis. After the injection in men with normal blood circulation in the penis, an erection will occur in 10 to 15 minutes. The physician then observes the erectile response, curvature of the penis, and response after erection. (A 1999 study suggested that many men with normal erectile function fail a first injection of prostaglandin E1 because of apprehension.)

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 problems of the endocrine system. A 1999 study suggests that testosterone level is an inadequate measure of sexual drive and that more research is needed to determine the value of routine assessments of this hormone in erectile dysfunction or low sexual drive. The physician 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 night-time 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 more 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 with professionals experienced in the use of the diagnostic instruments and in analyzing the data from them.

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:

 
• The penile brachial index is taken.  
• The storage ability of the penis is gauged.  
• An ultrasound of the penile arteries is performed.  
• An x-ray of the erect penis is taken.

Unfortunately, this test and other similar imaging techniques used to determine blood flow in the penis are currently not very effective or accurate in diagnosing and determining treatment.

Ultrasound. Ultrasound alone may prove to be useful in detecting some causes of erectile dysfunction, such as leakage from blood vessels.