Dr Robert Fox, an MS specialist at the Cleveland Clinic, explains in video below why recent  ultrasound studies on CCSVI have failed to replicate Zamboni’s findings. Dr Fox has found at least nine parameters that could seriously affect the diagnosis of CCSVI. Ultrasounds depend heavily on how the machine is set up, the skill of the radiologist, whether the study is blinded, patient positioning, the patient's hydration status,  respiration, heart rate, as well as pulse repetition frequency and other "knobology" factors.

Changing any one of these parameters can show that a patient is experiencing venous reflux or normal flow. For instance:

A relatively dehydrated patient could show up with abnormal velocity of blood flow and width of internal jugular vein.

If the radiologist pushes the transduser too hard on the neck could wrongly diagnose CCSVI.

If the ultrasound machine is wrongly calibrated patients could show blood flow reflux, even when there is none.

Lack of standardization in the ultrasound protocols, and their reporting, likely accounted for the vastly different results claimed by different research groups. Dr Fox is suggesting to reach a consensus on how exactly docs should test for CCSVI using ultrasounds. At the moment, Dr Fox argues, there is no enough information on how exactly Professor Zamboni has set up his ultrasound machine and the right parameters for not misdiagnosing.

You can watch the exclusive interview to Dr Fox at:

http://www.medpagetoday.com/Neurology/MultipleSclerosis/25931

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