Instead of "Plethysmography": "Kenoseography" and "Plesmonegraphy"

Abstract

The recording of volume changes in health and disease has from old been designated as "Plethysmography." This was supposed to be a correct term for the recording (graphein) of an increase in volume (plethysmos). The present paper shows that the choice of this term was not felicitous, and suggests an alternative. The first "plethysmographic" recordings are ascribed to Glisson (1622) and Swammerdam (1737).¹ Since Glisson and Swammerdam did, in fact, record the volume of muscle to be constant on contraction, their measurements should probably have been referred to as "isography." This, however, is merely a historical matter. Presently venous outflow measurement is a common proce dure to establish the diagnosis of deep vein thrombosis. Venous outflow is deter mined by recording the decrease in volume of a limb which occurs after release of a congestion cuff. As this is quite the opposite of what is meant by "Plethys mography," another indication is needed for this examination. It appears that a suitable alternative can be taken from ancient Greek medical literature.