Glossary

Packed Red Blood Cells – Concentrated red blood cells used for blood transfusion to improve the blood’s oxygen carrying capacity. When prepared the white blood cells and much of the plasma components of the volume of blood being processed are removed.

Pro re nata – Latin for “as the circumstance arises” or “in the circumstance”. In common medical use its meaning is “as needed” or “as the situation arises” and it is typically used in prescribing medications to be used as needed..

Proximal Range of Motion. This is the range of motion of a body part achieved when it is moved by an outside force such as an examiner moving an arm or leg of a person they are examining.

A hyper-coagulable state.  A propensity for blood clotting or coagulating in the veins as would be seen with an abnormality in the blood’s coagulation system.

Planning treatment volume – a term used when discussing radiotherapy that describes the gross tumor volume (the tumor bed at risk for recurrence or progression) plus a margin around it to account for 1) microscopic infiltration by tumor cells plus 2) the daily variation in targeting that is inherent in the equipment being used.

Periventricular leukomalacia. A white-matter brain injury seen in infants that is characterized by the periventricular (lateral ventricles) necrosis (usually coagulative) of white matter. Subsequent coalescence leads to porencephaly. Commonly seen in children with cerebral palsy, it is a marker for a brain injury occurring early in the third trimester.

Perfusion weighted imaging- A variety of MRI techniques used to measure blood flow and volume within the brain and generate maps about this perfusion of blood within the brain.

Pleomorphic Xanthoastrocytoma – a rare glial tumor occurring mostly in the supratentorial brain and having a very indolent behavior.

Quality Of Life

RApid Gradient Echo is a echo gradient MRI sequence used for a wide range of applications including angiography and perfusion techniques.