In making a diagnosis of erectile dysfunction (ED), your doctor will start by taking a detailed medical and psychosexual history and conducting a thorough physical examination. If possible, interviewing your partner also is very helpful in obtaining an accurate history, planning treatment and a successful outcome.
ED is often associated with various medical conditions, such as diabetes mellitus, coronary artery disease, hypertension, hyperlipidemia, spinal cord compression and pituitary tumors. Therefore, your doctor may conduct a variety of laboratory tests to determine the cause of your ED. These tests may include the following:
- Complete blood count
- Urine test
- Fasting blood glucose test
- Serum creatinine test
- Lipid profile
- Morning serum testosterone test
- Prolactin level test
Based on the results of these tests, your doctor will discuss with you — and if you would like, your partner — your goals, preferences and further diagnostic and therapeutic options. Experts at UCSF Medical Center believe that it is very important for patients (and their partners) to be well-informed and active participants in the decision making process regarding their care and treatment.
In some cases, your doctor may recommend that you have further testing for other medical conditions that may cause ED. In addition, if you are taking a drug, either prescribed or recreational, that is known to cause ED, or have vascular risk factors, a change in medication or lifestyle may be recommended.
A variety of self-report measures for assessing the levels of your sexual function are now available. These measures can be conducted on your own at home or in a private room at your doctor's office. The most commonly used test is the International Index of Erectile Function. It has 15 items and assesses erectile function, orgasmic function, sexual desire, intercourse satisfaction and overall satisfaction, as well as the severity of your ED.
Nocturnal Penile Tumescence (NPT) Test
Nocturnal erections occur in healthy males of all ages. Eighty percent of these happen during REM sleep. The average man has three to five episodes of NPT per night, lasting for 30 to 60 minutes each. With age, total nocturnal erection time decreases.
There are a variety of methods available for monitoring NPT. The monitoring is generally conducted with a simple outpatient device, rather than in NPT sleep labs. These devices electronically record the number, duration, rigidity and circumference of penile erections.
Psychological conditions, such as performance anxiety, a strained relationship, lack of sexual arousability and mental health disorders, including depression and schizophrenia, may cause erectile dysfunction. Therefore, your doctor may recommend an interview with a psychologist that focuses on current sexual problems, partner relationship and any psychiatric symptoms you may be experiencing.
At UCSF Medical Center, our urologists and neurologists work together to better understand and identify the causes of erectile dysfunction. Neurologic testing for ED is conducted at the UCSF Neurology Center at our Mount Zion campus.
The goal of neuro-urologic testing is to uncover neurologic disease, such as diabetes mellitus or pelvic injury, or diagnose reversible neurologic conditions, such as nerve damage caused by long-distance bicycling. These tests also help determine whether a referral to a neurologist is necessary. The most commonly used tests include:
- Combined Intracavernous Injection and Stimulation (CIS) Test This is the simplest, and most commonly used test for evaluating and diagnosing ED. It uses penile injections, visual or manual sexual stimulation and a subsequent erection.
- Color Doppler UltrasoundThis test uses harmless, non-invasive sound waves to produce a picture of the penile arteries, which enables experts to evaluate the arteries' functions.
- Pharmacologic Cavernosometry and Cavernosography These tests evaluate penile veins and help identify any venous leakages.
UCSF Health medical specialists have reviewed this information. It is for educational purposes only and is not intended to replace the advice of your doctor or other health care provider. We encourage you to discuss any questions or concerns you may have with your provider.