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Most techs see the order for a venous insufficiency study and cringe.  What follows is a simplified approach to the exam.  I hope it's helpful.  Chris  

Venous Insufficiency Duplex Imaging

 A simplified guide

Christine A. Unger, RVT, RPhS

Perform a full DVT study - be sure to measure the diameter of the SFJ and SPJ (if applicable) during compressions to avoid having to come back and do them again.  Be observant:  while in the groin scan up and down looking for accessory saphenous veins as well as the location of the proximal thigh GSV.  While in the popliteal fossa observe the presence or absence of the SPJ.

1. Obtain compression images of the CFV (prox and distal), SFJ, DFV, FV (prox, mid and distal), popliteal vein (prox and distal), PTVs and peroneal veins.
2. Obtain color filling images of the tibial veins, if you can, and of the common femoral and popliteal veins.
3. Obtain valsalva maneuver images in the CFV, SFJ , FV and popliteal vein.
4. Obtain augmentation images of the CFV (prox and distal), SFJ, DFV, FV (prox, mid and distal) and popliteal vein (prox and distal).

Do a contralateral study of the common femoral vein if the study is unilateral.

1. Obtain a compression image of the CFV.
2. Obtain an augmentation image that also shows phasicity before the augment.
3. Obtain a valsalva maneuver image.

Whatever order you use to obtain the above images is acceptable, as long as they are all there.  I generally do all my compression images from the groin to the popliteal fossa, turn my probe around and turn on the color and Doppler, then do all my augmentation and valsalva images from the popliteal fossa to the groin.  After completing that portion I concentrate on the calf veins – seems good economy of movement and I don’t have to augment with a slippery calf.

If acute DVT is found, perform a full bilateral DVT study and defer the reflux exam.

Of note:  We are professionals who find disease and document it accurately and honestly.  We perform these studies as we see them and would never document inaccurate information just to pander to the insurance companies.  But in the back of our minds, while performing the duplex, know that the insurance companies will not authorize treatment for the most mundane reasons.  Try to obtain images and measurements that fit in the guidelines if possible.  For instance, if you obtain a measurement of 5.2 mm of the proximal GSV, look around and make sure it is the widest measurement you can get.   Most insurance companies follow similar guidelines such as:

1. The SFJ must measure 5.5 mm or greater in diameter.
2. The proximal GSV must measure 5.5 mm or greater in diameter.
3. The accessory saphenous veins must measure 5.0 mm or greater in diameter.
4. The small SSV must measure 5.0 mm or greater in diameter.
5. Reflux of greater than 500 ms duration should be measured and documented.
6. Branches that are candidates for phlebectomy must measure 3.5 mm or greater in diameter, although that figure can vary from company to company.
7. Perforators must measure 3.5 mm or greater in diameter.
8. Perforator reflux of greater than 350 ms duration must be measured and documented.

Again, we are not pandering to the insurance companies, but if the patient has documentable findings that fit the above criteria, we must use due diligence in finding and documenting them.

Now that DVT has been ruled out, it’s time to do the reflux study.  The exam should be performed in the reverse trendelenberg  position or standing.  I would suggest  if your table does not tilt and you do not find significant reflux when varicosities or evidence of venous insufficiency are present, stand the patient and repeat augmentations of the superficial system in key spots above and below the knee.  If you can, check with the physician – some prefer all superficial measurements be performed in the standing position.  If I find significant vein dilation or significant reflux with the patient supine, I don’t stand them.

Return to the proximal thigh and do a split screen with compression and diameter measurement of the prox, mid, distal and above knee GSV.  As you’re scanning down the thigh, be observant and measure the diameter of any branches that look greater than 3.0 or 3.5 mm and indicate the level on the image.  Repeat for accessory saphenous veins if present.  Also , while scanning the thigh GSV, look for perforators in the distal thigh and document diameter in the same fashion.

 Follow the GSV below the knee and obtain prox, mid and distal diameter measurements with the split screen observing and measuring any branches.  I often find with advanced disease it can be difficult to discern between the GSV and branches below the knee – if that occurs, measure the diameter of all larger branches and indicate on your worksheet “the GSV was lost to multiple branches below the knee”.

 While below the knee, you should look for perforators.  They can be easily seen in transverse coursing between the deep and superficial system.  If you’re having a lot of difficulty finding them, let’s face it, they’re normal.  Don’t angst and just move on.  Sometimes perforators course between the deep system and branches.  Note that on the image and in your report -that information may influence whether the physician will treat the perforator or not.  Obtain diameter measurements and augmentations of perforators, measuring any significant reflux.

Now perform augmentations of the GSV.  You need three above and three below knee images (if the GSV can be followed below the knee).  Since I’m already below the knee I do those augments first.  For the distal BK GSV I squeeze the foot or the fleshy space below the medial malleolus.  You can also do a proximal compression at this level.  I do two more augmentation images below the knee, then clean off the medial calf and do augmentations above the knee.  Valsalva is very successful in producing reflux above the knee when you’re having trouble with distal compressions.  If the patient cannot perform valsalva for any reason, you can press with your hand the pelvic region for a few seconds and achieve valsalva that way.  If you observed any perforators above the knee, augment them when you’re in the closest proximity to them.

All that’s left is the SSV.  You should already know if the SFJ is present.  Use the same protocol as the GSV.  Obtain three compression images with split screen view and take diameter measurements, observing and measuring diameters of branches if present.  Obtain augmentations in the same fashion.  Often perforators exist, especially with advanced disease, between the gastrocnemius veins and the superficial system.  While scanning the posterior calf, scan through the posterior gastrocnemius muscle and document perforators if abnormal. 

Also observe any varicose vein clusters that are generally away from the saphenous system.  You can sometimes see a muscular perforator that can be documented.  It will appear as a vein that dives deep into the muscle away from the cluster and will usually be too small for treatment – but still it’s nice to find the cause of the cluster.

And now - you’re done. 

If you look at reflux studies as incremental scans and not an overwhelming task in front of you they will certainly be easier to handle.  I find professional pleasure in these studies, finding the root of the patient’s problem and becoming a part of the healing process.

Scan on sons and daughters of Hippocrates!