Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «V»:
Varicella vaccination: See Chickenpox immunization....
Varicocele: A common scrotal condition characterized by elongation and enlargement of the network of veins leaving the testis which join to form the testicular vein. (This venous network is called the pampiniform plexus.) A varicocele develops because of defective valves that normally let blood flow...
Varicose vein: A dilated (widened) tortuous (twisting) vein, usually involving a superficial vein in the leg, often associated
with incompetency of the valves in the vein. These visible and bulging veins are
often associated with symptoms such as tired, heavy, or aching limbs. In severe cases, var...
Varicose veins: See: Varicose vein....
Varicosity: 1. An enlarged and tortuous vein, artery, or lymphatic vessel.
2. Specifically, a varicose vein....
Variola: Smallpox, a highly
contagious and frequently fatal viral disease characterized
by a biphasic (double-humped) fever and a distinctive skin
rash that (if the patient survived) left pock marks in its
wake. The English physician Edward Jenner (1749-1823)
exploited the fact that cowpox c...
Variolation: The old practice of inoculating someone with the virus of smallpox to produce immunity to the disease. Lady Mary Wortley Montagu introduced this practice into England from Turkey in 1721. Unfortunately, the identification of a suitable strain of the virus was not an exact science and gr...
Varix: An enlarged and convoluted vein, artery or lymphatic
Varum: See: Varus....
Varus: (vara, varum) Angled inward, bent or twisted inward, as in cubitus varus, hallux varus, talipes equinovarus, genu varum, and coxa vara....
Vas deferens: The tube connecting the testes with the urethra. The vas deferens is a coiled duct that conveys sperm from the epididymis to the ejaculatory duct and the urethra....
Vasa previa: A condition in which blood vessels within the placenta or the umbilical cord are trapped between the fetus and the opening to the birth canal, a situation that carries a high risk the fetus may die from hemorrhage due to a blood vessel tearing at the time the fetal membranes rupture or ...
Vascular: Relating to the blood vessels of the body. The
blood vessels of the body, as a group, are referred to as the
The blood vessels are composed of arteries, veins and capillaries
-- arteries that pass oxygen-rich blood to the tissues of the body;
veins which return oxyge...
Vascular bed: The vascular system, or a
part thereof: for example, the pulmonary vascular bed
describes the blood vessels of the lungs....
Vascular dementia: A common form of dementia in older persons that is due to cerebrovascular disease, usually with stepwise deterioration from a series of small strokes and a patchy distribution of neurologic deficits affecting some functions and not others. Risk factors include high blood pressure,...