History taking should begin with a brief survey of the patient's demographics, including his age, his partner's age, the duration of his relationship with his partner, and the specific dynamics of that relationship.
Obtaining a good sexual history is imperative. Firstly, it is important to define which sexual dysfunction the patient is complaining of. It is not uncommon for patients to confuse ED with other sexual dysfunctions such as premature ejaculation, delayed ejaculation, or even retrograde ejaculation. Defining a patient's (and partner's) expectations and goals is also of value.
With regard to erectile dysfunction (ED), the key questions include duration of ED, degree of ED, erectile spontaneity, erectile sustainability, early morning/nocturnal erections, timing of last sexual intercourse, and whether the erectile dysfunction is situational or not. A brief assessment of the patient's psychological status is also critical. Specifically, it is important to define if there are overt risk factors for psychogenic ED.
History taking should then move to the medical and surgical history of the patient. Specific attention should be focused on vascular, neurological, and endocrinological issues that may represent risk factors for sexual dysfunction. Obtaining a good medication history is important. Many pharmacologic agents have been associated with erectile dysfunction; however, it is often difficult to determine whether it is the drug itself or the condition for which the patient is being treated that is the primary etiologic factor. A comprehensive social history is also important, which includes questions regarding tobacco, alcohol, and illicit drug use.
There are a number of validated questionnaires available that obtain information regarding a patient's sexual function. These include the International Index Of Erectile Function (IIEF), Sexual Health Inventory For Men (SHIM), and Men's Sexual Health Questionnaire (MSHQ), which are questionnaires routinely used at the Sexual Medicine Program in the Department of Urology at Weill Cornell Medicine.
The physical examination should focus on (1) secondary sexual characteristics, (2) abdominal examination, (3) major pulse examination, (4) S2-4 neurological assessment, and (5) external genitalia examination.
Examination of the penis should focus primarily on the presence of plaques and fibrosis. Examination of the testicles is aimed primarily at defining the presence or absence of masses, and at ascertaining the testicular volume and consistency. All men over the age of 40 years and those with lower urinary tract symptoms undergo digital rectal examination for prostate assessment.
All patients presenting with ED should have their blood pressure measured and a basic laboratory analysis.
The laboratory evaluation should include a lipid panel to assess for elevated cholesterol levels and serum glucose estimation in an effort to rule out the presence of diabetes. A serum testosterone level, although not imperative, is often also measured. Assessment of liver function tests and thyroid function tests are best reserved for those patients who manifest symptoms and/or signs suggestive of hepatic or thyroid dysfunction. ED is now recognized as a warning sign of silent cardiovascular disease. Certain at-risk patients should be considered for additional testing of cardiac status with an EKG, echocardiogram, or stress test. These should be ordered on a case-by-case basis.
In routine clinical practice, the majority of men presenting with erectile dysfunction do not require any further testing. However a number of investigations exist which are available to aid the clinician in assigning a cause to the patient's ED. Such investigations include (1) vascular testing, such as duplex penile ultrasound and dynamic infusion cavernosometry/cavernosography, (2) neurological testing, such as a biothesiometry, somatosensory evoked potentials and pudendal electromyography, and (3) nocturnal penile tumescence and rigidity analysis.
Adjunctive investigations may be useful for the following groups of patients: (1) patients with psychogenic ED, (2) young males with traumatically induced pure arteriogenic erectile dysfunction, (3) young males with isolated crural venous leak, and (4) patients with penile curvature prior to undergoing penile reconstructive surgery.