How Does a Man Get an Erection?
An erection is the result of increased blood flow into the penis. Blood flow is usually stimulated by either sexual thoughts or direct contact with the penis.
When a man becomes sexually excited, muscles in the penis relax. This relaxation allows for increased blood flow through the penile arteries. This blood fills two chambers inside the penis called the corpora cavernosa. As the chambers fill with blood, the penis grows rigid. Erection ends when the muscles contract and the accumulated blood can flow out through the penile veins.
ED can occur because of problems at any stage of the erection process. For example, the penile arteries may be too damaged to open properly and allow blood in.
Potential causes of ED are numerous. They include:
How is Erectile Dysfunction Diagnosed?
Medical and sexual histories help define the degree and nature of ED. Your medical history can disclose diseases that lead to ED, while a simple recounting of sexual activity might distinguish among problems with sexual desire, erection, ejaculation, or orgasm.
A physical exam can give clues to systemic problems. For example: if the penis is not sensitive to touching, a problem in the nervous system may be the cause. Abnormal secondary sex characteristics, such as hair pattern can point to hormonal problems which would mean the endocrine system is involved. The examiner might discover a circulatory problem or unusual characteristics of the penis that could suggest the source of the problem.
Several test can help diagnose Erectile Dysfunction. These include blood counts, urinalysis, lipid profile, and measurements of creatine and liver enzymes. Measuring the amount of free testosterone in the blood can yield information about problems with the endocrine system and is indicated especially in patients with decreased sexual desire.