Impotence

Definition

Erectile dysfunction is defined as a sustained or recurrent inability to get the penis sufficiently erect for sexual intercourse. As a result, the penis is not able to penetrate the vagina. Although problems with erectile dysfunction may occur at any age, about 50% of men aged 40-70 experience it, and the complete loss of erection increases with age. In Germany, there are six million affected men, illustrating that this is a frequent condition. Around 50-80% of the disorders are of organic origin, 30% are attributed to purely psychogenic disorders and 20% of men have a mixed form. Organic erectile dysfunction can be divided into vascular and non-vascular causes (cause related to the blood vessels).

Causes and diagnosis

Psychogenic causes primarily affect younger men. In this context, psychogenic means that the psychological factors are the primary reason for the erectile dysfunction. To diagnose psychogenic causes, the patient's psychosexual behavior and thoughts are assessed and any organic disturbances which affect the body's function are excluded. With psychogenic erectile dysfunction, nocturnal swelling of the penis and morning erections are still present, which can make it easier to differentiate between psychogenic and organic causes.

Organic causes are divided into vascular (affecting the blood vessels), neurogenic (involving the nerves), iatrogenic (caused by medical treatment) or traumatic origins.

Vascular causes can affect the arteries or veins of the man. The penis has three erectile tissues (two corpora cavernosa and one corpora spongiosum) that fill with blood during an erection. They are supplied with blood by the deep penile arteries and thereby lead to an erection. The venous valves are responsible for keeping blood in the erectile tissues. Causes of arterial impotence include lipid metabolism disorders, diabetes mellitus, hypertension, and nicotine abuse, as these factors lead to vascular changes associated with circulatory disorders. This usually results in a gradual decline in erectile function over the years.

Venous or erectile tissue dysfunctions can lead to a progressive decline in erectile function, often resulting in premature or complete loss of erection. Venous erectile dysfunction constitutes approximately 70% of vascular erectile dysfunction cases. In this condition, muscle tissue in the erectile tissues is replaced by connective tissue. This leads to gradual deterioration. Due to this, the muscles can no longer relax sufficiently to allow the erectile tissues to fill with blood, resulting in a diminished erection.

In another type of dysfunction, known as venogenic erectile dysfunction or venous leak, the muscle cells within the erectile tissues are also functionally impaired. This condition affects both the necessary muscle relaxation for an erection and the mechanism that maintains closure of the erectile tissues. In turn, this results in difficulties achieving a full erection. True venous leaks may also occur, where blood needed for an erection escapes prematurely. This disorder typically happens when the veins are not in the proper position in the penis and typically affects younger men.

Neurogenic causes concern the nerves that are, among other functions, responsible for initiating and maintaining an erection. Some of these causes include herniated discs, multiple sclerosis, postoperative nerve lesions after surgeries in the pelvic area, accidents leading to nerve lesions, and nerve disorders due to alcohol or diabetes mellitus. Polyneuropathies induced by diabetes mellitus commonly lead to erectile dysfunction. Erectile dysfunction caused by endocrine disorders should always be checked, particularly in older men. In this case, the erection can be impaired by hypogonadism (hypofunction of the testicles), hypo- or hyperthyroidism (thyroid gland) or a prolactinoma (tumor of the anterior pituitary gland). Naturally reduced testosterone levels after the age of 50 can also be a cause of erectile dysfunction. Besides erectile dysfunction, a decline in testosterone can also cause loss of libido, depressive mood, lack of drive, feeling fatigued quickly, decreased performance and hot flushes. After excluding prostate cancer, testosterone deficiency can be treated with a substitution of testosterone which has to be monitored regularly.

Symptoms

As mentioned above, the duration and strength of the erection is not sufficient for sexual intercourse. There is also no ejaculation during sexual intercourse. However, both can be achieved during masturbation. Often, there is no arousal due to private or professional concerns. In addition, the lack of an erection may impact sexual desire.

Doctor and diagnosis

It is important that the patient is questioned about their sexual and medication history. Furthermore, it is also necessary to determine whether alcohol, drug or nicotine abuse is present. The relevant hormones are also measured, metabolic disorders are ruled out (diabetes, vascular disorders) and the patient's neurological status, or nerve function, is examined. The swelling of the penis at night is also measured (nocturnal penile tumescence), laboratory parameters (testosterone, blood sugar, FSH, LH, prolactin) are examined and a Doppler ultrasound is performed to examine the penis and blood vessels.

Treatment

Treatment is based on a combination of physical training, psychotherapeutic measures, testosterone substitution and treatment of neuropathy, or nerve dysfunction. Erectile dysfunction can also be treated with medication like sildenafil, tadalafil or vardenafil.  Another type of therapy is erectile tissue auto injection therapy, in which substances that promote the formation of an erection are injected. Additionally, vacuum pumps can be used to facilitate an erection, or surgery can be performed to implant prosthetic devices into the penis.