Erectile dysfunction is the inability to obtain or maintain an erection adequate for intercourse and long enough to  satisfy both partners. This spectrum extends from total inability to obtain an erection to the inability to consistently obtain an adequate erection for an adequate duration.
Erection
The penis has 3 chambers, 2 of which are the corpora cavernosa. The third is the corpus spongiosum and contains the urethra. With sensory or mental stimulation blood fills the corpora cavernosa bilaterally creating pressure in the chambers and  resulting in an erect penis.
Causes of Erectile Dysfunction
Neurologic damage secondary to disease is the number one cause of ED. These diseases may include diabetes, kidney disease, alcoholism, vascular disease and various neurologic diseases. Trauma either accidental or secondary to surgery is another neurologic cause.
Smoking, obesity and lack of exercise are other common causes of erectile dysfunction. Medications such as blood pressure medications, medications used for heart disease, some cholesterol medications, antidepressants and many recreational or illegal drugs are common causes of erectile dysfunction.
Psychological causes once thought to cause more then 80% of the cases of erectile dysfunction now account for less then 20%.
Diagnosis for Erectile Dysfunction
History and physical help define the cause of erectile dysfunction. The history should include questions about desire, last sexual encounter, use of legal or illegal drugs.
Physical exam including a neurological exam, size and consistency of the testes, secondary sex characteristics and finally any penile deformity (Peyronie’s).
Laboratory testing includes hormone levels, liver panel, lipids and renal function.
Treatment for Erectile Dysfunction
Treatment starts from the least invasive to most. First place to start is lifestyle changes, quitting smoking, decreasing alcohol consumption, weight loss and increase in exercise.
It is also very important to review all medications to see if there are any that are associated with erectile dysfunction. Today there are multiple drugs available to treat disease so changing medications is not as difficult as in the past.
Drug and Surgical Treatment
Drugs available to treat erectile dysfunction have changed rapidly in the last 10-15 years prior to the advent of sildenafil citrate (Viagra) type drugs, urologist routinely evaluated the patient and started them on yohimbine with questionable results. They progressed to vacuum devises and then to injections. These individuals were labled with psychogenic impotence 80% of the time.
Today it is common to use sildenafil citrate type medications to treat these  patients, after a thorough evaluation is done. If this fails many patients are given a trial with a vacuum tumescence devise or penile injections. The injections are self administered, injections into the corporal bodies. The resistant cases move onto surgical correction using inflatable cylinders placed in the corporal bodies.The cylinders are attached to a pump located in the scotum and a reservoir implanted in the abdomen. When a patient is ready for sexually activity several squeezes on the pump resuls in an erection. Afterward the fluid is released and returns to reservoir leaving a physiologically flaccid penis.
Related articles include. “Low Testosterone Levels”, Â “Symptoms of Male Menopause“, “Good Blood Flow Means Better Sex”, and “Testosterone Therapy“.
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