The state of the penis when it is filled with blood and becomes rigid. The penis contains two chambers called the corpora cavernosa, which run the length of the organ, are filled with spongy tissue, and 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 and mental stimulation. Impulses from the brain and local nerves cause the muscles of the corpora cavernosa to relax, allowing blood to flow in and fill the open spaces. The blood creates pressure in the corpora cavernosa, making the penis expand. The tunica albuginea helps to trap the blood in the corpora cavernosa, thereby sustaining erection. Erection is reversed when muscles in the penis contract, stopping the inflow of blood and opening outflow channels.
- Penis, hypospadias of the
A birth defect in which the urethra opens on the underside of the penis or below the penis. Treatment involves surgery to repair and reconstruct the urethra.
- Penis, inflammation of the foreskin and glans
inflammation of both the glans and foreskin. Circumcision prevents balanoposthitis. Without a foreskin, there can of course be no posthitis and hence no balanoposthitis. An uncircumcised boy should be taught to clean his penis with care to prevent infection and inflammation of the foreskin and the glans penis. Cleaning of the penis is done by […]
- Penis, inflammation of the head of the
inflammation of both the glans and foreskin. Circumcision prevents balanoposthitis. Without a foreskin, there can of course be no posthitis and hence no balanoposthitis.
- Penis, small
A penis that is abnormally small, also known as micropenis. In medical practice, the dimension of the penis that is measured is the length. This measurement is taken along the upper surface of the shaft of the penis to the tip, using a measuring tape or preferably a ruler. The ruler is pressed firmly into […]
- Penrose drain
A soft tube-shaped rubber or silicone drain. Named for the American gynecologist Charles Bingham Penrose (1862-1925).