MR venography of multiple sclerosis

Abstract

Background and purpose: The distribution of multiple sclerosis (MS) lesions in the brain follows a specific pattern, with most lesions in the periventricular regions and in the deep white matter; histopathologic studies have shown a perivenous distribution. The aim of this study was to illustrate these distribution patterns in vivo using high-resolution MR venography.

Methods: Seventeen MS patients underwent MR imaging at 1.5 T. Venographic studies were obtained with a 3D gradient-echo technique. MS lesions were identified on T2-weighted images, and their shape, orientation, and location were compared with the venous anatomy on the venograms.

Results: The use of contrast material facilitated the visualization of small veins and increased the number of veins seen. A total of 95 MS lesions could be identified on both the T2-weighted series and the venograms; a central vein was visible in all 43 periventricular lesions and in all but one of the 52 focal deep white matter lesions. The typical ovoid shape and orientation of the long axis of the MS lesions correlated well with the course of these veins.

Conclusion: With MR venography, the perivenous distribution of MS lesions in the brain can be visualized in vivo. The venous anatomy defines the typical form and orientation of these lesions.

fig 1.

A and B, Axial T2-weighted MR image (7000/112/2) (A) at the level of the lateral ventricles and corresponding contrast-enhanced MR venogram (67/50/1) (B). The inset in B is the minimum intensity projection image calculated over 7.5 mm of the boxed area. The form and orientation of the left periventricular MS lesion (wide arrow) corresponds to the course of the longitudinal caudate vein. The lesion at the posterior limb of the right internal capsule (thin arrow) corresponds to the course of a striate vein. Curved arrow indicates internal cerebral vein; open arrow, septal vein

fig 2.

A and B, Axial T2-weighted MR image (7000/112/2) (A) at the level of the lateral ventricles and corresponding contrast-enhanced MR venogram (67/50/1) (B), with magnified image shown in boxed area. Periventricular lesions as well as a deep white matter lesion (straight arrow) and subcortical lesion (bent arrow) are demonstrated. The form and orientation of the lesions correspond to the course of their in-plane running central vein. The deep medullary vein running through the deep white matter lesion drains into the septal vein, and the caudate veins drain into the thalamostriate vein (curved arrow)

fig 3.

A and B, Axial T2-weighted image (7000/112/2) (A) and corresponding contrast-enhanced MR venogram (67/50/1) (B) with magnified image shown in boxed area. The lesion at the left occipital horn (long wide arrow) is hypointense, with ring enhancement visible on the T1-weighted SE image (not shown). The MR venogram shows a vein with its course corresponding to the form of the lesion. Note the susceptibility artifacts in the frontal regions and the low intensity of the globus pallidus (open arrow), substantia nigra (short wide arrow), and red nucleus (thin arrow)