Category: V

  • Visual evoked response

    Stimulation of the retina of the eye with light causes changes in the electrical activity of the cerebral cortex. These changes can be measured from outside the skull and can give valuable information about the state of the visual pathway from the retinal ganglion cells to the occipital cortex. Not only can it determine that…

  • Viral haemorrhagic fever

    Viral Haemorrhagic Fever, or ebola virus disease. A usually fatal infection caused by a virus related to that of marburg disease. Two large outbreaks were recorded in 1976 (one in the Sudan and one in Zaire), with a mortality, respectively, of 50 and 80 per cent, and the disease reappeared in the Sudan in 1979.…

  • Vinorelbine

    A semi-synthetic vinca alkaloid cytotoxic drug used in the treatment of advanced breast cancer, when anthracycline cytotoxic antibiotics such as doxorubicin have failed. Vinorelbine is also used to treat advanced non-small-cell lung cancer. As with all vinca alkaloids, the drug has neurotoxic effects, usually affecting the peripheral nervous system and autonomic nervous system. It may…

  • Vinca alkaloids

    A group of powerful cytotoxic (anticancer) drugs used to treat acute leukaemia lymphoma and some solid tumours such as breast and lung cancers. Originally derived from the periwinkle plant, the latest vinca alkaloid (vinorelbine) is a semi-synthetic drug. These alkaloids, which are given intravenously, have potentially serious side-effects on the nervous system and also suppress…

  • Vestibulo ocular reflex

    Eye movement that occurs after or during the slow injection of 20 ml of ice-cold water into each external auditory meatus in turn, used as a test for inner ear function.  

  • Vertebrobasilar insuffiency

    Intermittent incidents of double vision, dizziness, weakness and speaking difficulties caused by a reduced blood supply to parts of the brain. The cause is usually obstruction in the basilar, vertebral and other arteries at the base of the brain. The condition is sometimes the precursor of a stroke.  

  • Version or turning

    Version or turning: the name given to an operation in obstetrics consisting of turning the fetus in the uterus if the former is lying in an abnormal position which may make eventual delivery difficult. In particular, version (which can take place spontaneously) may be done on a fetus between the 34th and 37th weeks of…

  • Van den bergh test

    A test done on serum from patients with jaundice to discover whether the excess bilirubin in the blood which causes the jaundice is conjugated or unconjugated. If conjugated, this indicates that haemolysis is causing the jaundice; if unconjugated, disease of the liver or bile duct is the likely diagnosis. A diagnostic procedure for measuring bilirubin…

  • Virtual colonoscopy

    A procedure that links computed tomography of the colon with techniques that produce three-dimensional views of the mucosa of the large bowel similar to those obtained during traditional colonoscopy. Early experience suggests that the new technique produces better results than barium enemas and is almost as effective as conventional colonoscopy. Virtual colonoscopy offers faster results, and…

  • Vulnerable adult

    A grownup with some perceived impairment, who requires special protection. The definition of vulnerable adult varies. In Minnesota, a “vulnerable adult” is defined as any person 18 years of age or older who is a resident or an inpatient at a licensed facility (hospital, nursing home) or who receives care from a licensed home care…