Dr. Fox, an American neurologist from the Cleveland Clinic, was in the press in Canada last week, commenting on Dr. Laupacis' meta analysis. Dr. Fox has been conducting his own research, utilizing doppler technology. I'll break down the abstract below (abstract in italics, my comments in normal type.
http://registration.akm.ch/einsicht.php?XNABSTRACT_ID=138456&XNSPRACHE_ID=2&XNKONGRESS_ID=150&XNMASKEN_ID=900
Chronic cerebro-spinal venous insufficiency (CCSVI) 2
Friday, October 21, 2011, 15:30 - 17:00
Ultrasound assessment of chronic cerebrospinal venous insufficiency
R. Fox, L. Baus, C. Diaconu, A. Grattan, I. Katzan, S. Kim, M. Lu, L. Raber, A. Rae-Grant (Cleveland, US)
Background: Chronic cerebrospinal venous insufficiency (CCSVI) is a new theory of MS pathogenesis involving alterations in extracranial and intracranial venous outflow. Proposed diagnostic criteria for CCSVI is derived from ultrasound assessments, although different studies have found varying incidence of MS patients and non-MS controls meeting CCSVI criteria.
This is very true....Dr. Zamboni's diagnostic criteria found CCSVI in 100% of pwMS. But it was not utilized in most of the later doppler studies. Dr. Fox's group has tried to replicate Dr. Zamboni's diagnotic procedure.
Objective: To perform an independent, blinded study of CCSVI in MS and non-MS controls.
Methods: After obtaining formal training in ultrasound assessment for CCSVI, we performed CCSVI assessment in MS and non-MS controls. All ultrasounds were conducted using a Biosound MyLab25Gold machine, which included Quality Doppler Profiles (QDP) technology for assessment of flow in the deep cerebral veins. The internal jugular, vertebral, and deep cerebral veins were assessed in both supine and sitting positions. Both QDP and traditional Doppler were used to assess intracranial venous flow in the deep cerebral veins. Ultrasound technicians were blinded to diagnosis, including the use of separate research staff to position patients prior to arrival of the technician. All ultrasounds were over-read by a trained physician, who was also blinded to the MS diagnosis.
This is important to note: this study utilized the same manufacturer of transcranial doppler that Dr. Zamboni has created, the Esaote Biosound, which BNAC has used, as well. The QDP is the complete protocol.
Results: The study is ongoing, but initial pooled results from the first 20 subjects found that 6 (30%) met >=2 criteria for CCSVI. 1 subject met 3 criteria. Four subjects met no criteria. No subjects met criteria for reverted postural control of cerebral venous outflow. Nine subjects (45%) had a flap and/or septum/abnormal valve. No flow in the IJV was observed in only one patient. Deep cerebral vein reflux was observed in 7 (35%) of subjects using QDP, but never using transcranial color Doppler (TCCD).
Additional ultrasound evaluations are ongoing, and results according to diagnosis (MS vs. non-MS controls) will be presented.
This is a small study, only 20 patients tested, but it is being blinded, which is important. A couple more important notes: Intraluminal defects were noted in 45% of the subjects. And deep cerebral reflux is noted when the FULL Zamboni protocol is used....which means the transcranial doppler PLUS the Quality Doppler Profile. The studies which do not include Dr. Zamboni's FULL QDP analysis will miss deep cerebral vein reflux. This complete protocol is a must, and there is a learning curve with it (which is why the BNAC studies did not include it at the start.) BNAC stated that it took them six months to completely incorporate the full Zamboni technique....this is not simple, and the amount of time doing the diagnostics may have affected the results in this preliminary trial.
Conclusion: Initial pooled results found that 30% of subjects met criteria for CCSVI. A high proportion of subjects (45%) had valvular or intraluminal abnormalities on B-mode. Surprisingly, no subjects were found to have reverted postural control. Identification of deep cerebral vein reflux depended upon the ultrasound technique: QDP found reflux in half of subjects, but traditional Doppler found reflux in none. This observation highlights the importance of ultrasound methodology in performing and interpreting deep cerebral vein assessments. Ongoing studies will help clarify the potential relationship between CCSVI and MS.
Dr. Fox has received speaking and consulting fees from Biogen Idec, Genentech, Novartis, and Teva Neuroscience, and grant or research support from Biogen Idec and Genentech. Dr Rae-Grant has received honoraria for speaking from Biogen IDEC and Teva Neurosciences within the past year. Dr. Katzan has received speaking honoraria-Genentech Inc. Dr. Kim has been involved in consulting for Philips with compensation, and received financial support for research from American College of Cardiology supported by GE. Dr. Lu, Diaconu, Baus, Gratten and Raber have nothing to disclose. Current study is supported by the National MS Society (RC 1004-A-5).
So, one correctly done, preliminary study amidst dozens of negative studies will be presented at ECTRIMS this year....I hope that Dr. Fox continues to keep an open and independent mind.
Joan