Inverse Relationship between Internal Jugular Vein Narrowing and Increased Brain Volumes in Healthy Individuals – Podium Presentation - #42
Chris Magnano, M.S., 1,2, Pavel Belov1, Jacqueline Krawiecki1, Steven Grisafi1, Jesper Hagemeier1, M.S., Clive, B. Beggs, Ph.D. 3, Robert Zivadinov 1,2, M.D., Ph.D.
Background: Brain volume reduction (atrophy) and internal jugular vein (IJV) narrowing have been implicated in central nervous system pathologies, but have never previously been linked.
Objectives: To assess the relationship between cross-sectional area (CSA) of IJVs and brain volumes in healthy individuals (HI).
Methods: 131 HI received 2-dimensional magnetic resonance venography and structural MRI at 3T. Region of interest (ROI) analysis was performed using a semiautomated countring-thresholding technique to determine the minimum CSA of the IJVs at C2/C3, C4, C5/C6, and C7/T1 cervical levels. Normalized volumes of the whole brain, gray matter (GM) and white matter (WM) were assessed using the Structural Image Evaluation using Normalization of Atrophy (SIENAX) cross-sectional method. Partial correlation analyses were used to determine associations.
Results: Reduced CSA was related to increased GM volumes at all cervical levels, with distal CSA cervical locations (C7/T1) demonstrating the most robust correlations, whereas proximal levels (C2/C3) had weaker but still significant correlations (r=-.337, p<.001 at C7/T1, r=-.259, p=.004 at C5/C6, r=-.252, p=.005 at C4, and r=-.217, p=.018 at C2/C3). Similar effects were found for whole brain volumes, although proximal correlations were weaker than distal ones (r=-.347, p<.001 at C7/T1, r=-.244, p=.007 at C5/C6, r=-.181, p=.047 at C4, and r=-.166, p=.070 at C2/C3).
Conclusion: The reduction of the IJV CSA was associated with increased brain volumes, suggesting that narrowing the IJVs may be accompanied by swelling, edema, or venous stasis in the brain parenchyma. These findings are in line with recent observations reported in Alzheimer’s disease patients, showing jugular venous reflux is associated with increased brain volumes, and warrant further investigation.
The presence of jugular narrowings in healthy controls has been considered an argument against CCSVI as an abnormality. This research, however, suggests that healthy controls are not healthy controls after all. There is an association between smaller jugular veins and increased brain volumes. That increase in brain volume may be a result of swelling, edema or venous stasis. In this case, a bigger brain is not better, not if it's a swollen brain. This is research that supports the existence of CCSVI as a disorder in its own right, regardless of the association to multiple sclerosis.