Cessation of flow on Valsalva maneuver:

Another technique to assess the patency and absence of thrombus in the part of the venous system above the point of examination is to use the Valsalva maneuver. During deep inspiration and holding of breath, there is normal abrupt cessation of flow in the vein. In image above, the superficial femoral vein shows total cessation of flow. This is therefore, normal.


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