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Duplex scanning to evaluate the effect of compression on venous reflux.

AIM
The aim of this study was to demonstrate the usefulness of Duplex in measuring venous reflux and changes in reflux caused by leg compression.


METHODS
Twelve patients with severe incompetence of the great saphenous vein (GSV) were investigated. A special Duplex probe was fixed by tapes on the mid-thigh portion of the incompetent GSV and reflux elicited by tip toeing was measured. Elastic and inelastic compression material with an interface supine pressure around 20, 40 and 60 mmHg was applied on the lower leg and the reflux measurement was repeated.


RESULTS
Increasing compression of the leg led to a progressive reduction of the reflux in the GSV. Ultimately reflux was completely abolished by inelastic compression with a median pressure of 86 mm Hg in the standing position. Elastic material exerting this pressure can achieve similar results but is not tolerated by patients.


CONCLUSION
Duplex is able to demonstrate a reduction of GSV reflux caused by compression of the lower leg, which explains one major beneficial effect of compression on the disturbed haemodynamics in venous incompetence.