Glossary

The ration of the length of the line from the basion (anterior, midline rim of Foramen Magnum) to the posterior arch of C1 divided by the distance of the line from the anterior arch of C1 to the opisthion (posterior, midline rim of the Foramen Magnum).  An equal length in the two lines (quotient of one) is normal, whereas a ratio or quotient of first line divided by the second suggests a possible atlanta-occipital dislocation, ann odontoid fracture or a fracture of the ring of the atlas (C1).

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.

Refers to breaking apart or destroying a protein.

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.

Prothrombin Time – a laboratory blood test for a component of the body’s blood clotting system.

Partial Thromboplastin Time – a laboratory blood test of a component of the body’s blood clotting 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.