Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «T»:
Turner-Kieser syndrome: See Nail-patella syndrome....
TVS: Abbreviation for "transvaginal ultrasound," a technique in which sound waves are sent out by an ultrasound probe that has been inserted in the vagina. The waves go through the vaginal wall and bounce off the ovaries, and a computer uses the ultrasound echoes to create a picture (a sonogram).
Twelfth cranial nerve
Twelfth cranial nerve: The hypoglossal nerve. The twelve cranial nerves, including the hypoglossal nerve, emerge from or enter the skull (the cranium). The hypoglossal nerve supplies the muscles of the tongue. Paralysis of the hypoglossal nerve affects the tongue. It impairs speech (it sounds thick...
Twenty-twenty: Perfectly normal vision. From the ability to score 20/20 on the test of visual acuity with the eye chart. This familiar chart, called Snellen's chart after its inventor, is usually read while standing a distance of 20 feet from it. Visual acuity is traditionally represented as a fract...
Twilight sleep: A term applied to the combination of analgesia (pain relief) and amnesia (loss of memory) produced by a mixture of morphine and scopolamine ("scope") given by a hypodermic injection (an injection under the skin). The mixture of the two drugs created a state in which the woman, while ...
Twin: One of two children
produced in the same pregnancy and born during the same birth process.
Twins can develop from one ovum (egg) or from two ova (eggs):
Twins from one ovum: Twins that develop from a single
ovum are called monozygotic. They are said to identical twins and have
Twin, vanishing: See: Vanishing twin....
Twisted ankle: See: Ankle sprain...
Twitch: an involuntary contraction of a group of muscles, also known as a
Twitching: Involuntary contractions of groups of muscle fibers. Also known as
fasciculations. Fasciculations can occur in normal individuals without an
associated disease or condition and can also occur as a result of illness, such
as muscle cramps, nerve diseases, and metabolism imbalances. ...
Two-animal rule: A rule instituted by the US Food and Drug Administration (FDA) for the licensing of agents directed against diseases of low or no incidence. The two-animal rule states that, when agents such as an antibiotic or vaccine are needed for such diseases, these agents may be licensed if th...
Two-faced twin: Known medically as diprosopus, two-faced twins are conjoined twins (incompletely separated identical twins). The twins have almost complete fusion of their bodies with one set of limbs. Part or all of the face is duplicated. The condition usually results in stillbirth.
The ancient t...
TXA2: Thromboxane A2, the active form of thromboxane....
TXB2: Thromboxane B2, the inactive product of thromboxane....
Tylenol: See: Acetaminophen....