Yulin Ge MD, Presenter: Nothing to Disclose

Meng Law MD, Abstract Co-Author: Nothing to Disclose

Robert Ivin Grossman MD, Abstract Co-Author: Nothing to Disclose

Perivascular inflammation is a critical event in the pathogenesis and evolution of multiple sclerosis (MS). This study is to demonstrate the association of prominent perivascular spaces with MS lesions which may be an important sign in differentiating primary (ie. in MS) from secondary causes of demyelination.

A retrospective review of imaging data from 23 consecutive patients who have been diagnosed as clinically definite MS was performed. MR imaging was performed on a 1.5T and 3.0T clinical scanners. Dual echo fast spin-echo, PD - and T2-weighted imaging (TR/TE: 2500/18, 90ms, 256x256 matrix on 1.5T and 7900/17, 119ms; 512x512 matrix on 3.0T) and FLAIR (TR/TE/TI: 9000/110/2500msec) performed followed by enhanced T1-weighted imaging (TR/TE: 600/27ms). The slice thickness is 3 mm. Comparison was made with MR imaging in seventeen age-matched controls.

Prominent perivacular spaces were observed in patients with MS. The imaging appearance of these perivascular spaces include: 1) abnormal string-like hyperintensities were observed in 15 of 23 patients that are located in the periventricular or subcortical regions and are oriented perpendicular to lateral ventricular surface; 2) these are best visualized on dual echo fast spin-echo sequences, but not visualized in control group; 3) unlike Virchow-Robin (VR) space, these string-like hyperintesities do not follow the lenticulostrate arteries as extensions of the subarachnoid space, they appear to follow the course and configuration of deep venular structures; 4) are usually demonstrated to be most prominent adjacent to lesion plaques unlike the VR spaces seen in ischemic disease; 5) can be visualized in patients with early phase or with long term standing disease; 6) are more prominent on high field imaging with higher resolution acquisitions.

The perivascular spaces adjacent to MS lesions are shown to be abnormally prominent. We believe this sign may be secondary to increased inflammatory activity initially resulting in dilatation of the perivascular spaces. This may provide a sign to differentiate primary from secondary causes of demyelination, as well as serve as a useful marker of disease activity and progression.

Ge, Y, Law, M, Grossman, R, Prominent Perivascular Spaces in Multiple Sclerosis as a Sign of Perivascular Inflammation in Primary Demyelination.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4413768.html