Setting the Standard for Care…
The most up-to-date techniques
A variety of techniques are used to diagnose CCSVI. Some, like Doppler ultrasound (DUS) and Magnetic Resonance Venography (MRV) are screening tests that can non-invasively determine whether there is a likelihood that a patient has CCSVI. These non-invasive tests make sense because they are less expensive and take less time, maximizing the number of patients who can learn whether or not they have the condition without risk. Zamboni and colleagues have reported that the presence of at least two of the criteria separates healthy controls from patients with CCSVI.
The majority of Interventional Radiologists at American Access Care have chosen Doppler Ultrasound as the primary screening test for a variety of reasons, mainly because it has been well tested and shown to detect CCSVI. It is so non-invasive that it can be completed without intravenous, sedation or holding still in a long tube with loud noises – just a little jelly on the neck! Our centers use the Zamboni Doppler Protocol for ultrasound diagnostic screening.
However, the test requires that the operator use specific techniques and pay strict attention to details to get a reliable result. All of our technologists have undergone at least one week of rigoroustraining to become proficient in administering the test. The training has allowed our technologists to standardize their approach to diagnosis, making it possible to undergo screening in one location and follow-up imaging at another, a great convenience for patients who do not want to be confined to one location throughout the year.
While DUS and MRI are helpful screening tests, the definitive test for evaluating CCSVI remains the catheter based venogram. Considered the Gold Standard it has provided direct real time visualization of the inner space of the vein and detected narrowing of the veins implicated in chronic cerebrospinal venous insufficiency for more than forty years. The procedure is minimally invasive with little cutting, performed under local anesthesia. Most patients are awake and relaxed during the procedure. This reduces risks.
A superficial vein in the left leg, usually the femoral vein, is punctured by a small needle with precise ultrasound guidance. The needle hole is enlarged to allow the introduction of a sheath by stretching with dilators rather than cutting, reducing injury to the vein and promoting rapid healing. Our physicians have recently modified the technique to puncture a smaller vein next to the femoral vein, called the saphenous vein so that the risk of injury to the main leg vein is diminished.
Using fluoroscopy or X-ray guidance, small tubes called catheters are navigated within the circulation into the neck and chest veins. Venography creates images by injecting a radio-opaque dye into the veins to help identify any narrowing or blockages. We generally perform the following venograms: right and left internal jugular veins, the azygous vein, the left renal vein, the left ascending lumbar vein, the left iliac vein and inferior vena cava. We sometimes check the dural sinuses to assure that the outflow veins in the brain have a good connection with the veins outside the brain. We will also study the external and anterior jugular veins, and the vertebral veins as needed.
Venography requires considerable expertise and experience to successfully and safely traverse through the veins into the proper channels. Identification of the proper blood vessels and recognition of abnormal veins requires familiarity with the many normal and abnormal presentations of these veins. Our physicians are specialists in venous interventions and perform more venous angioplasties than any other group in the United States.
However, venography is not perfect and some abnormalities may go unrecognized. American Access Care is at the forefront in assessing the value of intravascular ultrasound (IVUS) as an second test for evaluating venous pathology. An ultrasound device on a guidewire replaces the diagnostic catheter. It bounces sound waves off the interior of the vein and shows excellent characterization of the interior of the vein including the valves that are so commonly diseased in CCSVI. This technique increases the accuracy of the overall venous evaluation while allowing more precise measurements of the diameter of the veins and more precise selection of balloon size.
At the first annual meeting of the International Society for Neurovascular Disease, American Access Care Physicians using IVUS were the first to clearly demonstrate that venous narrowings were most commonly the result of valves that could not open rather than scar tissue in the vein wall. Our physicians were the first to treat CCSVI by IVUS alone without xray dye, enabling treatment of patients who had been told by other physicians that they could not be treated because of severe venogram dye allergies.
If a narrowing is observed, a balloon on a catheter can be placed in the constricted part of the vein and inflated to dilate the narrowing. This procedure, commonly known as angioplasty, helps stretch the stenosed veins and open constricted valves.
Restoring normal vein size allows proper blood flow through the vein. No expense is spared in selecting balloon design. We use balloon catheters with the highest burst pressure rating as high pressure is commonly necessary in order to overcome the forces that are causing the narrowing. Underpressurizing the balloon will only stretch the narrowed area temporarily, often causing elastic recoil to occur and result in restenosis.
In the rare cases where the balloon angioplasty does not eliminate the stenosis, a small stent may be needed to help open the vein and restore normal vein size and blood flow. American Access Care considers stenting to be an unusual requirement as high pressure angioplasty is usually sufficient to open stenoses. Stents are indicated for recurrent restenosis, angioplasty injury that retards flow, and for stenoses that do not respond to angioplasty, the so-called elastic stenosis.
Our goals for treatment are three-fold: safety, improved quality of life, and stabilization of neurological deterioration. First, we have worked diligently to develop a treatment protocol that reduces thrombosis and bleeding risks, while working toward retardation of restenosis and prolonging the effects of angioplasty.
American Access Care believes that stenoses of the outflow veins of the brain and spine is a distinct clinical entity. We suspect that venous obstructions can result in distinct clinical problems such as fatigue, spasticity, balance issues, and memory and cognitive problems. We do not think that what we do reverses the effects of demyelinization. How else to explain sudden return of color vision, hearing or reduction in spasticity?
Many of our patients have enjoyed improved quality of life by reducing spasticity, improving memory and reversing chronic fatigue. We do not make outlandish claims and long term outcome results will take time to determine. We are committed to using our experience to help understand CCSVI better.