Glossary

A narrowing of arteries due to vasoconstriction (persistent tightening of vessels).  This can be present after a subarachnoid hemorrhage.  It can alter the amount of blood through an involved vessel and, in some cases, completely block flow.  When severe it leads to ischemia in the tissues perfused by the vessel and can culminate in a stroke.

An association (syndrome) of birth defects consisting of Vertebral anomalies, Anal atresia, TracheoeEophageal fistula and Renal and/or Radial anomalies. This association has been enlarged to VACTERL to include Cardiovascular anomalies and Limb defects.

Voiding CystoUrethroGram – A procedure used to observe how the bladder accumulates and empties urine. The test is done by introducing a catheter into the bladder then injecting contrast agent into the bladder while watching with fluoroscopy (video x-ray). After filling the bladder with contrast, the patient is asked ot empty the bladder. During the test the examiner looks for how well the bladder can hold the injected urine, any indication of contrast entering the ureters that connect the bladder with the kidneys (reflux) and how successfully the bladder is emptied on command.

Vascular endothelial growth factor – This is a signaling protein in the platelet-derived growth factor family that stimulates vasculogenesis and angiogenesis. It is secreted by cells where there is oxygen deprivation in the normal state and also are secreted by rapidly growing population of cells such as occur with cancers.

Vascular Endothelial Growth Factor Receptor. A family of receptor tyrosine kinases that play a crucial role in regulating angiogenesis (blood vessel formation) and lymphangiogenesis (lymphatic vessel formation). Abnormalities in these proteins with associated disruption in signaling pathways are instrumental in many diseases.

VI = FHI /ID, where the FHI or frontal horn index is the largest width of the frontal horns and ID is the internal diameter from inner table to inner table at this level.

Vertical Expandable Prosthetic Titanium Rod.  This curved, metal rod that attaches to ribs or the spine using hooks present at each end of the rod.  It is used to straighten the spine and correct chest deformities by separating the ribs.

von Hippel Lindau – VHL is an autosomal dominant genetic condition (mutation of the 3p25.3 chromsome’s von Hipple-Lindau suppressor gene) associated within central nervous system, the retina of hte eye and the kidneys. It is rare with a prevalence fo 1 in 35,000 to 50,000 individuals. There are other associated pathologies including renal angioma, renal cell carcinoma (clear cell variety) and pheochromocytoma.

an intermediate filament found in cells. It was once thought to found only in mesenchymal cells and as a consequence staining for this element was thought ot be specific for sarcomas dn other mesenchymal cell tumors. This has not proven to be the case and it has been shown to be present in many tumors to a point that it’s routine use is diminishing.

Ventriculo-peritoneal – as in ventricular peritoneal shunt, a hydrocephalic shunt whose distal catheter drains into the peritoneal cavity.