Abnormally low levels of the male sex hormone testosterone in the blood. Testosterone is produced by the testes and to a lesser extent by the adrenal glands. Testosterone encourages the development of male sexual characteristics at puberty, stimulates the activity of the male secondary sex characteristics, drives the production of sperm, and is involved in regulation of muscle mass and sex drive. Testosterone levels are highly regulated by a complex glandular system. Abnormally low testosterone levels can occur due to a number of conditions affecting the glands that regulate and produce this hormone. Symptoms of low testosterone include decreased libido, impotence or erectile dysfunction, breast enlargement, and a lowered sperm count. Low testosterone levels may be treated with hormone therapy.
- Low vision
A visual impairment, not corrected by standard glasses, contact lenses, medicine, or surgery, that interferes with the ability to perform everyday activities. Low vision can be a result of eye conditions such as nystagmus, intraocular trauma, inflammation or retinal conditions such as diabetic retinopathy or age-related macular degeneration (AME). Low vision primarily affects people over […]
- Low vision device
A devise to help to improve visual ability of a person with low vision. Low vision devices may be optical or non-optical. Optical devices such as a magnifying glass involve the use of lenses to improve vision whereas non-optical devices such as large print help bring images closer to the eyes.
- Low-grade lymphoma
A lymphoma that tends to grow and spread slowly, in contrast to an intermediate- or high-grade lymphoma which tends to grow and spread more quickly. Low-grade lymphomas include chronic lymphocytic lymphoma and follicular small cleaved cell lymphoma. Also called an indolent lymphoma.
- Low-set ear
A minor anomaly in which the ear is situated below the normal location. Technically, the ear is low-set when the helix of the ear meets the cranium at a level below that of a horizontal plane through both inner canthi (the inside corners of the eyes). The presence of two or more minor anomalies such […]
- Lower GI series
Short for lower gastrointestinal series. A series of x-rays of the rectum, colon and lower section of the small intestine taken after the patient has a barium enema. Barium is a white, chalky substance that coats the organs so they will show up on the x-ray. Also called a barium enema or a barium enema […]