Venous outflow measurement in the diagnosis of deep vein thrombosis--principles and practice.

Venous outflow measurement (kenoseography) is increasingly applied in the diagnosis of deep vein thrombosis. Performance and interpretation of this examination have a considerable influence on the final result. The influence of congestion pressure, outflow determination, positioning of the patient and the site of measurement are discussed. One should be aware that figures obtained by one institution can not always be applied by others.