A Venous Reflux study uses a PPG probe affixed adjacent to the posterior tibial artery, at or above the ankle. Dorsiflexing the foot acts as a pump for venous augmentation. Recovery time is the time required for venous refilling to occur. Venous Reflux is used to assess valvular competence. PPG probes are available for the Bidop® 3, Smartdop® 45, Smartdop® 30EX, and Smartdop® 50EXF Dopplers.
Examination Procedure
Connect the PPG probe and make sure the Doppler is in DC or Venous mode.
Have the patient sit on an examination table so that the feet are not touching the floor. Use double-sided clear tape to affix the PPG sensor to the skin surface at the medial malleolus over the posterior tibial vein.
Ask the patient to dorsiflex the foot the specified number of time. The exercise should be performed forcefully, especially when lifting the foot upward.
After dorsiflexing, have the patient relax the foot. The waveform on the LCD will return to baseline and display the results.
Interpreting the Results
Normal refill time will exceed 21 seconds
Refill time between 18 and 21 seconds is questionable. Repeat the test.
If refill time is less than 18 seconds, a venous condition may exist.
Proper technique and patient cooperation are important factors when performing a venous reflux study.
The instructions provided above are intended as general guidelines. For specific instructions on performing a Venous Reflux study using your specific Doppler, please refer to the operation manual and/or inservice video provided.
