Erectile dysfunction


Erectile dysfunction (ED), sometimes called impotence, is the repeated inability to get or keep an erection firm enough for sexual intercourse. Impotence may also be used to describe other problems that interfere with sexual intercourse and reproduction, such as lack of sexual desire and problems with ejaculation or orgasm.
Estimates suggest that between 15 and 30 million (20-40%) Americans suffer from ED. There are approximately 26 new cases annually of ED in the United States per 1,000 population in men 40 to 69 years of age. Over 150 million men worldwide suffer from ED.
Although ED is more common in men older than 65, it can occur at any age. An occasional episode of erectile dysfunction happens to most men and is normal. As men age, it is also normal to experience changes in erectile function. Erections may take longer to develop, may not be as rigid or may require more direct stimulation to be achieved. Men may also notice that orgasms are less intense, the volume of ejaculate is reduced, and recovery time increases between erections.
Erection: The penis (male sexual organ) contains two chambers called the corpora cavernosa, which run the length of the penis shaft. The corpora cavernosa are surrounded by a membrane, called the tunica albuginea. The spongy tissue contains smooth muscles, fibrous tissues, spaces, veins, and arteries. The urethra, which is the channel for urine and ejaculate, runs along the underside of the corpora cavernosa. Erection begins with sensory or mental stimulation (either touch or image), or both. Impulses from the brain and local nerves cause the muscles of the corpora cavernosa to relax, allowing blood to flow in and fill the spaces. The blood creates pressure in the corpora cavernosa, making the penis expand. The tunica albuginea helps trap the blood in the corpora cavernosa, thereby sustaining erection. When muscles in the penis contract to stop the inflow of blood and open outflow channels, erection is reversed.

Related Terms

Adrenal gland, Alzheimer's disease, atherosclerosis, axillary, bulbocavernosus reflex test, cavernosography, cavernosometry, climax, coronary heart disease (CAD), corpora cavernosa, corpus spongiosum, diabetes, digital rectal examination (DRE), duplex ultrasound, ejaculate, erection, fibrous, glans, gynecomastia, hyperprolactinemea, hypogonadism, impotence, intraurethral, libido, Medicated Urethral System for Erection (MUSE), multiple sclerosis, neuropathy, nitrates, nitric oxide, nocturnal penile tumescence (NPT), orgasm, paraplegia, Parkinson's disease, penile biothesiometry, Peyronie's disease, pituitary gland, plaque, prolactin, quadriplegia, seminal fluid, sexual intercourse, sperm, stroke, substance abuse, testosterone, tunica albuginea, urethra, vascular, vascular reconstructive, surgery, vasoactive, venous leak.