Erectile Dysfunction (Impotence)
Definition of ED
Erectile dysfunction (ED) is defined as the inability to achieve and/or maintain an erection that is suitable for sexual intercourse. Erectile dysfunction is often referred to as “impotence”. However this term is no longer used. It is important to distinguish erectile dysfunction from other forms of sexual problems such as low libido or premature ejaculation.
How an erection occurs
An erection is obtained by the spongy tissues in the penis becoming engorged with blood. This vascular process is initiated by a signal from the brain that travels down the spinal cord through the pelvis directing blood vessels in the penis to dilate. There are chemical factors involved in this vascular process and the mechanism that traps the blood in the penis is known as the veno-occlusive mechanism. When this does not work effectively the leakage of blood is known as “venous leakage”. This may occur as a psychological issue when anxiety is present during sexual activity or as a consequence of the physical changes of ageing and the effects of other medical conditions such as diabetes and coronary artery disease.
The causes of ED
The causes of ED may involve problems with the brain and nervous system, the arteries and veins in the penis and the penile spongy tissues (cavernosal tissues). Conditions such as high cholesterol, high blood pressure, diabetes and obstructive sleep apnoea may be associated with erectile dysfunction. Some medications used to treat these medical conditions may affect the erection process and these include blood pressure and cholesterol lowering tablets. Medications should never be stopped if is it suspected they are contributing to ED but the concern over the potential effect on sexual function should be raised with your treating doctor.
Peyronie’s disease may affect erections with the presence of painful scar tissue resulting in curvature of the erection. Excessive alcohol intake and substance abuse are other known factors. ED may occur after surgery to the abdomen, pelvis and prostate. ED can also associated in older men who have urinary changes from benign prostate enlargement. For further information, see the document on Peyronie’s disease.
ED due to psychological causes is called performance anxiety, often seen in younger men but can be present across all age groups. It may involve anxiety and lack of confidence at the beginning of a sexual relationship or may present with difficulty maintaining the erection when applying a condom. The anxiety with erections can result from relationship stress or other stresses like financial issues or as a result of other sexual issues such as premature ejaculation. Performance anxiety can improve in time but may require education and counselling and the use of medication.
Erections and ageing
The presence of ED in a younger man is often due to psychological causes but in some cases due to a congenital anomaly of the penile erection tissues or blood vessels, this is called veno-occlusive dysfunction or “venous leakage”. ED is an increasing issue in older men. About 1 in 3 men over the age of 50 complain of erectile difficulties. It is important to stress that the change in erections with age is not necessarily a physical disorder requiring treatment, often an understanding of the nature of these changes is sufficient treatment alone. The firmness of the erection changes with age and the time taken (the refractory period) to re-engage in sexual activity increases in time with age.
Investigation of ED
As ED may be associated with vascular conditions particularly present in the older man, it is thus important to carry out a full general health check including the heart. Overnight erection testing may assist in establishing in a younger man whether the cause is physical or psychological. It is usual for a man to experience during rapid eye movement sleep between 3 to 5 erections each night. High cholesterol and high glucose are checked with blood tests, which can also check the health of the liver, kidneys, iron stores, thyroid, prostate as well the level of the male hormone testosterone. Men with suspected venous leak undergo Duplex Doppler ultrasound scan of the penile blood flow to check the status of the arteries and erection tissues and a procedure called cavernosography or cavernosogram to view the site of the venous leakage and check penile pressures.
The treatment of ED
Counselling: Treatment of erectile dysfunction may simply involve counselling and explanation of the normal anatomy and physiology of erections. Counselling can benefit relationship issues that may be contributing to the erection problems.
Oral medication: A common and popular treatment these days is the use of oral medications known as PDE5 inhibitors. The products available on the Australian market include Viagra™, Cialis™ or Levitra™ tablets. These medications are taken as required 1-2 hours before planned sexual intercourse. These medications are effective in most situations but cannot be used if the patient is not fit enough to engage in sexual intercourse or is on nitrate medication. For further information, see document on PDE5 inhibitors.
Penile injections: When oral medication is not effective, penile injection therapy may work. The injection is self administered into the shaft of the penis, the dose needs to be carefully regulated so that a prolonged erection (priapism) does not occur. The injection medication may consist of a single chemical called prostaglandin (PGE1) or alprostadil known as Caverject Impulse™ available by a doctor’s prescription through a regular pharmacy. If the single medication injection is not adequate, then a compounded triple mixture that contains PGE1, phentolamine and papaverine is obtained through an approved compounding chemist. Priapism is defined as an erection lasting more than 4 hours and is treated with the application of ice packs and the taking of pseudo-ephedrine tablets (Sudafed™). Occasionally a visit is required to the local emergency room to drain the priapism.
Vacuum device: A less invasive treatment is the use of a vacuum erection device that allows an erection to occur by creating a vacuum with a plastic cylinder placed over the flaccid penis. The induced erection is then held in place by a constricting band placed around the base of the penis for a maximum time of 30 minutes.
Shock wave therapy: Low intensity extra corporeal acoustic shock wave therapy is a recent innovation relying on the effects of sound waves when applied to the shaft of the penis creating new blood vessels (angiogenesis). Shock wave therapy works best in men with ED arising from penile blood flow changes (vasculogenic ED). It may change a poor PDE5i responder to an improved PDE5i responder.
Surgery: In some cases regular treatments are not effective and a final treatment option is to insert a penile prosthesis or implant which is an internally placed hydraulic device that has no obvious external appearance of the genitals. This operation is performed by a urologist.
Vascular surgery is mainly performed in younger men when trauma has damaged the blood vessels leading to the genitals. Some men with venous leakage may benefit from erectile restoration veinsurgery or vein stripping surgery.