Overview
Impotence is defined as the inability to achieve or maintain an erection suitable for sexual intercourse. More than 20 million men are affected with impotence, and it has been estimated that greater than 35 percent of men over the age of 60 suffer with some degree of impotence.
Penile erection occurs when nerve signals are received in the penis resulting in dilation of arteries causing an increased blood flow to the erectile tissue of the penis. The erectile bodies are known as the corporal bodies or corpora cavernosa. The blood that flows into the penis must then be trapped within the corporal bodies by a passive process which results in occlusion of the veins which drain the penis.
Impotence (sometimes referred to as erectile dysfunction) is commonly divided into two categories: psychogenic and organic. We now appreciate that most cases of impotence have a significant organic component and that few patients have pure psychogenic impotence. Based upon our knowledge of the physiology of penile erection, organic impotence can be divided into cases caused by diseases of the nervous system (e.g., diabetes), disorders of the circulatory system (e.g., arteriosclerosis) or disorders allowing the blood to leak out of the penis prematurely (so-called venous leak impotence).
Evaluation
Patients who present with complaints of impotence are evaluated with a detailed medical history to identify obvious causes such as medications known to be linked to impotence. Further information is obtained regarding lifestyle issues such as smoking and illicit drug use which may affect a man's ability to obtain an erection. Obvious physical problems like diabetes are addressed at this time. Certain historical factors are also of importance. For example, a man who relates a history of decreased libido (sex drive) may have deficient production of the male hormone testosterone.
After a thorough history and physical examination are performed, baseline testing is done. We generally recommend that a blood sample be obtained to determine if the patient's testosterone level is adequate. In some cases nocturnal penile tumescence monitoring is done to evaluate the quality of the patient's nocturnal erections. This test helps determine whether or not the patient is experiencing nighttime erections. This is important because men normally have multiple erections during various phases of the sleep cycle and if a significant decrease in this activity is noted, the impotence is more likely to be organic than psychogenic.
Treatment
Following complete evaluation, treatment recommendations are made. Although some men will be found to have psychogenic impotence and will be referred for counseling, most men will be found to have organic impotence and at this point we review various treatment options. Generally speaking, the options can be divided into nonsurgical and surgical treatments.
Men who are found to be producing inadequate amounts of testosterone are begun on replacement therapy. Testosterone therapy can be either in the form of biweekly injections or patches which are applied to the skin.
One very effective treatment option is a product called Caverject®. The medication is directly injected into the penis resulting in dilation of the penile blood vessels and an erection.
Another popular form of nonsurgical treatment is the vacuum erection device. This system utilizes a plastic cylinder which is placed over the penis temporarily while a small pump is used to create negative pressure. The blood which is "pulled" into the penis is then trapped with a rubber band around the base of the penis and the vacuum is released allowing removal of the cylinder from the erect penis.
The first oral medication for the treatment of impotence was approved by the FDA in the last week of March, 1998. The drug is called Viagra® (sildenafil). Since the introduction of Viagra, Cialis® and Levitra® have been approved by the FDA. These medications are taken orally, and when the patient is sexually stimulated, the drug causes the penile blood vessels to dilate resulting in an erection.
Surgical therapy for erectile dysfunction consists mainly of the penile prosthesis. Although both semi-rigid and inflatable devices are available, most men choose an inflatable prosthesis because it results in a much more normal looking penis in both the flaccid and the erect state.
For more information on erectile dysfunction and its treatment, please visit our frequently asked questions page where links to manufacturers of many of the products listed above can be found.