I’ve already had an ultrasound, elsewhere, why do I need another one?
- Posted on: Sep 22 2020
There are many different types of ultrasound studies available to help your doctor diagnose and treat your condition. The first question we would then ask is, “What type of ultrasound exam did you have?”. Was it a venous or arterial study? If it was venous a exam, we would then want to know if it was a reflux study or was it done to rule out a blood clot? We have found that many patients have had an ultrasound to rule out a blood clot but they were not checked for reflux.
Our veins have one-way valves to keep blood flowing towards the heart. Normal venous flow should go upward against the force of gravity. When valves become weaken over time they can cease to close properly causing the blood to also flow backwards. This backwards flow is called reflux and this is what we are looking for during your doppler ultrasound exam at our office. This reflux is responsible for the varicose veins that can cause pain, swelling, achiness, ropy like veins and night time cramp just to name a few of the common symptoms. To adequately measure reflux, the exam should be done in a standing position. This is another reason we may have to repeat an exam as we commonly find that many outside ultrasound exams were done completely with the patient in a seated or lying position.
Another common question is, “So how can you tell the difference between an arterial versus a venous exam?”. If the exam is to check the arterial flow, at some point the ultrasound technician will put a blood pressure cuff on your arms and ankles to take your blood pressures and will then compare the pressures in your arms to that in your legs. In a typical exam in our office, we will also place a cuff on your legs that resembles a blood pressure cuff but the difference is that a blood pressure cuff for the arterial exam gets tight just like when you get your blood pressure checked and the cuff that we use to check for reflux is just a quick, light squeeze.
If you’ve had an exam to rule out a DVT blood clot, they you will notice some similarities to our exam. In an ultrasound exam to rule out DVT the ultrasound technician will run the probe down your leg pressing with the ultrasound probe. A reflux ultrasound exam will start the same way. The difference is, that after we have evaluated the deep veins we will have you stand and will then check for reflux by squeezing the lower leg with a blood pressure cuff, hands or legs.
Please note that during a doppler exam to check for venous reflux, the standing portion of the exam is extremely important. Standing allows us to get a more accurate picture of the presence of a reflux.
When do your veins stick out the most? When do your legs swell? When do they hurt the most? It is most likely after you have been standing. Gravity is always pulling in a downward direction, it is thus much easier to see reflux or backwards flow when you are standing and your veins are running vertically than when you are lying down and the veins are thus perpendicular to the direction of gravitational force. This is why your veins are larger when you’ve been standing. We also need to document accurate sizes of the veins as many insurances have size requirements before they will cover vein treatments. Taking measurements in a standing position allows us to see what is really going on and thus get more accurate dimensions. We find that many outside exams do not properly document the measurements required by insurance companies.
At Northern Michigan Vein Specialists, we are accredited in vascular testing. This means we have met the accreditation commission guidelines and standards specifically for the doppler exams that we provide in our office for testing for venous reflux, and rule-out DVTs (blood clots). In addition, our ultrasound technicians need to be a RVT (Registered Vascular Technician). Dr. Heeringa and Bill Holland also have the RPhS (Registered Phlebology Sonographer) credential. This means we are dedicated to the diagnosis of vein related issues.
Please feel free to contact our office directly at 231-946-1488, if you have any questions about venous ultrasound testing. Thank you.
– Bill Holland, RVT RPhS