Prevalence of Incidental Narrowing of the Superior Segment of the Internal Jugular Vein in Patients Without Multiple Sclerosis
F. E. Diehn MD, K. M. Schwartz MD, C. H. Hunt MD, L. J. Eckel MD, N. G. Campeau MD, R. E. Carter PhD, J. B. Allred, D. F. Kallmes MD
Internal jugular vein (IJV) narrowing superiorly is likely relatively frequent. IJV narrowing has been proposed as a potential pathophysiologic component for multiple sclerosis (MS). Our purpose was to investigate the prevalence of incidental superior IJV narrowing in patients imaged with neck computed tomography angiography (CTA) for reasons unrelated to IJV pathology or MS.
We retrospectively identified 164 consecutive adult patients who had undergone neck CTA in which at least one IJV superior segment was opacified (158 right, 155 left IJVs). At the narrowest point of the upper IJV, each IJV was assessed for dominance, graded (shape and narrowing), measured (diameter and area), and located (axially and craniocaudally). Associations were analyzed using Spearman rank correlations (p < 0.05 significant). Medical records were reviewed for MS.
Among 164 patients, at least one IJV was: absent/pinpoint in 15 % (25/164), occluded/nearly occluded in 26 % (43/164). Shape, narrowing, and the three measurements all correlated with each other (all p < 0.01). Lateral location with respect to C1 transverse foramen correlated with subjectively and objectively smaller IJVs (p < 0.01). The most common craniocaudal location was at the C1 transverse process (79 % (125/158) of right and 81 % (126/155) of left IJVs). No patient had a diagnosis of MS.
The appearance of the superior IJV is variable, with an occlusive/near-occlusive appearance present in approximately one-quarter of patients without known MS undergoing CTA. Radiologists should be aware of and cautious to report or ascribe clinical significance to this frequent anatomic variant.
Ok this is a different approach: they looked through CTA scans to identify patients with upper jugular narrowings, then reviewed the medical records for MS. This didn't pan out but perhaps a larger study would find an assocation. It's an interesting approach. If there was a database looking at the jugular in the lower neck area for reasons unrelated to MS, it could be checked to see if there was a higher incidence of MS in patients with jugular valve stenosis.
Anyway the conclusion here was that in about 25% of the CT scans, there was upper jugular narrowing without any MS diagnosis, and that this is an anatomic variant that may be without clinical significance.
I'd have to check but I thought Dr. Sclafani said he saw true upper jugular narrowings in about 5% of patients? So that is less even than what was found in this study.