[The value of postural plethysmography in the study of venous physiology and in the evaluation of vasotonic agents].

Venous physiology is generally neglected and badly studied. Knowledge of it is nevertheless essential in pathological cases such as venous incompetence and its treatment. It is this which is principally responsible for cardio-vascular adaptation after positional changes. Mercury gauge venous occlusion plethysmography has contributed certain progress. Postural mercury gauge plethysmography without venous occlusion answers the chief physiological preoccupations. No artefact impedes the physiology. The positional adaptation is tested. A DV/DP diagram is established and compared in normal subjects and patients with venous incompetence. A complementary procedure for a microcirculatory study is proposed: the measurement of cutaneous flux using laser Doppler or photoplethysmography and a study of the permeability of the capillary walls using fluorescein videodensitometry. This veritable testing stand of the venous system can serve as reference for procedures of therapeutic tests for all medication for venous tropism (vasotonics, vasodilators of venous location) or in studies on spatial medicine.