[Limitations of venous function diagnosis using laboratory apparatus - possibility of errors]

The authors discuss some questions concerning the limitations and the errors of methods involving the Sonar Doppler, Plethysmography and Phlebodynamics in phlebology diagnosis. The Doppler technique is the most useful one in detecting a valvular insufficiency or a venous obstruction of the thigh. Plethysmography is a simple method of detecting a pelvic or femoral thrombosis. It does not make it possible, on the level of the calf, to make a distinction between a recent thrombosis or a post-thrombotic state. It cannot be used when there is a large edema. It is inadequate for studying the function of the muscular pump of the calf, which can also be done by phlebodynamics. This method is now the most precise technique for quantitatively studying the total function of the muscular pump of the calf. It can be easily reproduced, and the effect of therapeutic measures can thus be anticipated.