measurement of variation in blood pressure
• (n.) The study, by means of the plethysmograph, of the variations in size of a limb, and hence of its blood supply.
measurement of changes in the volume of an organ or in the volume of blood within an organ
Method used to find problems with blood flow in the body. It works by detecting the electrical energy generated by blood flow.
(pleth″iz-mog´rә-fe) the determination of changes in volume by means of a plethysmograph. air-cuff plethysmography a technique for measuring changes in the circumference of a limb by recording the changes in pressure in an air-filled cuff surrounding the limb. ...
Pleth`ys·mog'ra·phy noun (Physiol.) The study, by means of the plethysmograph, of the variations in size of a limb, and hence of its blood supply. 
Type: Term Pronunciation: pleth′iz-mog′ră-fē Definitions: 1. Measuring and recording changes in volume of an organ or other part of the body by a plethysmograph.
plethysmography Measuring and recording changes in the volume of the body or of a body part or organ.