brocktoon wrote:Are you going to be at the Sherbrooke conference this weekend? I am eager to present and discuss our latest findings with you. I will have to read up on the Trabbaloussee research in the meanwhile.
brocktoon wrote:Another big problem with this study is that the MS group is not separated in any way, which hinders the ability to analyze the data properly. Our group has already replicated the bar graph with our recent MRI flow findings and we have observed similar findings to the Rodger paper, but when the MS group is separated into stenotic and non-stenotic subgroups, we see lower IJV flow in the stenotic group compared to the controls and non-stenotic MS groups. We still have to work on the statistics for the data set though and hope to have a paper on it within a few months.
Classification of Venous Outflow in the Extracranial Vessels in a Large Cohort of MS Patients
Sean Sethi, MS, David Utriainen, Robert Loman, MD, Imran Saqib, E. Mark Haacke, Ph.D. – MR Innovations, Inc., Wayne State University
Background: MRI is a viable modality for evaluating structure and function of the extracranial vessels.
Objectives:To re-evaluate extracranial vessel blood flow using in-house software SPIN (Detroit, MI), and to classify venous collateral flow in MS and normal control populations using MS data from four different imaging sites using MRI.
Methods: A group of 67 healthy control (HC) subjects as well as 761 multiple sclerosis (MS) subjects from four different imaging sites were imaged with 3T MRI scanners using a comprehensive CCSVI protocol. Phase contrast flow quantification (PC-FQ) and MR Venography imaging were exclusively used to quantify blood flow of the extracranial vessels and to anatomically characterize subjects into stenotic (ST) and non-stenotic groups. Venous vessel flows were normalized to arterial flow at the C2/C3 and C5/C6 vertebral level. Data were analyzed and subjects were classified into different venous collateral groups based on four different pathways. Determination of delay between IJV peak flow and carotid systolic peak flow was analyzed to determine whether there were differences in time delay for each group.
Results: In the MS cohort, more than 50% of the subjects were ST. Normalized IJV flow for the ST-MS group was similar for each site, and lower than the NST group and the HC groups—which were found to have similar normalized IJV flow. The ST group also showed higher flow in Type 3 and Type 4 venous collaterals, indicating a longer transit time for extracranial venous blood to drain back to the heart.
Conclusion: This shows further evidence for abnormal flow in the MS cohort not only in the IJVs, but non-primary venous pathways as well.
Quantitative Flow Differences between Multiple Sclerosis and Healthy Control Subjects
Sean Sethi, MS, David Utriainen, BS, Wei Feng, PhD, Ana M. Daugherty, MA, Naftali Raz, Ph.D., J. Joseph, Hewett, MD, E. Mark Haacke, Ph.D.
Background: MRI is a reliable method for quantifying blood flow and visualizing head and neck vasculature in 3D.
Objectives: To provide a retrospective, statistical analysis on a group of healthy control (HC), stenotic MS (ST), and non-stenotic MS (NST) subjects to determine the optimum flow thresholds to differentiate HC from MS.
Methods: A group of 138 MS and 67 HC subjects were imaged on 3T Siemens scanners between two sites. Both 2D TOF MRV and 3D time resolved CE MRAV were used to determine if IJV stenosis was present, subdividing the MS group into ST and NST. The 2D PC was used to quantify flow through the major arteries and IJVs at both C2 and C6 levels. The ratio between the larger IJV flow (dJ) versus the smaller IJV flow (sdJ) was calculated as sdJ/dJ. IJV flow was then normalized to the total arterial flow (tA), providing two major criteria for both levels, the tIJV/tA, where tIJV is the sum of both IJV flows, and sdJ/tA. MANOVA and ROC curve analysis were done. Significance was determined at p=0.05.
Results: In the MS sample, 66 (48%) were NST and 72 (52%) were ST. When comparing the ST and HC groups, optimum thresholds were determined to be: 0.62 for C6tIJV/tA, 0.66 for C2tIJV/tA, 0.16 for C6sdJ/tA, 0.10 for C2sdJ/tA, 0.31 for C6sdJ/dJ, and 0.14 for C2sdJ/dJ. The subjects that meet both: tIJV/tA criteria are 9% HC, 11% NST, and 61% of ST; sdJ/tA criteria are 13% HC, 6% NST, and 60% ST;and sdJ/dJ criteria are 13% HC, 7% NST, and 44% ST.
Conclusion: The current sample of MS patients and HC indicates that there is a statistically significant difference in venous outflow through the IJV between the two groups. These criteria may provide the means of assessing vascular abnormalities in MS subjects quickly using MRI
brocktoon wrote:Yes, that is our work. I should mention that only the second abstract (138 vs 67) was literally submitted to American Journal of Neuroradiology last week. It is a very robust paper so I am excited and hopeful to hear back from them.
The first abstract "Classification..." paper is not done yet, but we finally have the data for about 650 MS and 67 HC, so I would be cautious in quoting it.
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