ISNVD Abstract Book

FLOW THROUGH THE INTERNAL JUGULAR VEIN IS REDUCED
FOR MULTIPLE SCLEROSIS PATIENTS WITH STENOSES
COMPARED TO THOSE WITHOUT OBSERVED BY MRI
W. Feng 1 , D. Utriainen 2 , Z. Wu 3 , D. Hubbard 4 , E. M. Haacke 1,2
1
Department of Radiology, Wayne State University, Detroit, Michigan 48201; 2 Magnetic Resonance Innovations, Inc., Detroit, MI 48202;
3
Department of Surgery, Morehouse School of Medicine, Atlanta, Georgia, 30310; 4 Applied fMRI Institute, San Diego, CA 92131
INTRODUCTION
Chronic cerebrospinal venous insufficiency (CCSVI) has been suggested to play an important role in multiple sclerosis (MS) patients [1]. Studies of venous flow of MS patients
were mostly performed with ultrasound imaging. Our recent work using contrast enhanced MRA (CE-MRA), 2D time-of-flight MRV (TOF-MRV) and phase contrast MRI (PC-
MRI) has shown that the internal jugular vein (IJV) flow at the cervical 6 (C6) level is reduced for patients with anatomically stenotic IJVs [2]. Stenoses of the IJVs usually occur
at either upper neck level (around C2) or lower neck level (around C6). Here we further investigate the extracranial venous flow characteristics by studying the differences
between the MS populations with stenotic IJVs at C2 and C6 levels.
METHODS
The study was approved by local institutional review board. Two hundred and seventeen (217) clinically definite MS patients and 15 normals signed informed consent forms
and participated in the study. Three-dimensional CE-MRA data were collected to locate IJV stenoses by examination of the vasculature and multiple 2D TOF-MRV data with
high in-plane resolution was used to measure vessel cross-sectional area (CSA) to determine stenoses. Thresholds of 25mm 2 around the cervical 6 (C6) level and 12.5mm 2
around the C2 level were used to determine IJV stenosis. Based on this stenosis assessment, all subjects were divided into 3 groups, non-stenotic (NST), C2 stenotic (C2ST)
and C6 stenotic (C6ST). Subjects with both C2ST and C6ST were classified as C6ST. Blood flow was measured with 2D PC-MRI imaging around C6 level perpendicular to the
IJVs on a 3T Siemens Magnetom Tim Trio with the following parameters: TR = 14.4ms, TE = 4.41ms, flip angle = 25 o , FOV = 256mm×256mm, in-plane resolution =
0.57mm×0.57mm, slice thickness = 4mm and maximum encoding velocity (VENC) = 50cm/sec. Retrospective pulse gating was used and a total of 25 images were
reconstructed during one cardiac cycle. Vessel segmentation was achieved manually using our in-house MATLAB software. Occasional aliasing in major vessels was mostly
corrected by a simple phase unwrapping algorithm [2]. Statistical analysis was performed to compare the quantitative findings among the groups. Paired and unpaired t-tests
were performed as appropriate to evaluate the statistical significance of the differences.
RESULTS
Of the 217 subjects, 99 (45.6%) were determined to be in the NST
group, 54 (24.9%) in the C2ST group and the remaining 64 (29.5%) in
the C6ST group. Table 1 shows the quantitative flow measurements.
There was no significant difference among the total arterial flow rates
for the NST, C2ST and C6ST groups (16.16±2.73, 16.80±2.96 and
16.26±2.56 mL/sec, respectively; p=0.18 between NST and C2ST,
p=0.29 between C2ST and C6ST). For the whole population, the flow
difference through the left and right common carotid arteries were not
significant (6.51±1.31 vs. 6.57±1.34 mL/sec, respectively; p = 0.37).
These findings, while not directly on the venous system, indicate that
the method was not biased toward any group. On the venous side, the
blood flow through the LIJV was found to be significantly less than that
of the RIJV (4.31 ± 2.66 vs. 6.36 ± 3.06mL/sec, respectively; p2/3), (28.7, 54.0, 47.6, 33.3) % were type II (1/3 1/3; type
III: FIJV/Fta