Diffusion Weighted Imaging Changes in Multiple Sclerosis Patients

Background: The role of Diffuse Weighted Image (DWI) in the evaluation of Multiple sclerosis has not been well established.  DWI allows measurement of the apparent diffusion coefficient (ADC) of water in the brain. Together with perfusion imaging is an important tool for the evaluation of acute stroke but all restrictive diffusions are due to stroke. Potential applications of DWI technique include all pathologies that affect cellular integrity including MS.

Objectives: Evaluate the prevalence of DWI changes in MS and the radiographic correlation of DWI changes with disease activity.

Methods: Retrospective study, 100 electronic records from RRMS patients were reviewed. Time of diagnosis, treatment history, symptoms, burden of disease were documented. Brain MRI was evaluated for the presence of DWI changes in association to hypo or hypeintense in ADC sequence. (Restriction vs T2 shine trough lesions) and for the presence of enhancing lesions.  Follow up MRI was evaluated for the persistence of DWI lesions or the presence of new affected areas.

Results: Epidemiologic data and medication history will be presented in table 1. DWI changes were observed in 62 (51.9–71.1) patients (12 % with DWI restriction). The odds of presenting active enhancing lesions were significantly higher if DWI lesions were detected after adjusting for MS current treatment, age, gender and duration of disease, with a p value of <0.001.Location of enhancing lesions did not always correspond to the lesions showing restriction or T2 shine trough.   75% of the patient with DWI restrictions had also T2 shine trough lesions in other areas of the brain not corresponding to the enhancing lesion or to the one that was showing restriction. All patients who presented with DWI restriction lesions were symptomatic and experienced a clinical aggressive course.

Conclusions: We appreciated association between disease activity and the presence of DWI changes. All patients with DWI restriction showed evidence of disease activity and had an aggressive course of disease. MRI findings could be secondary to the mechanism of neuronal injury which may correspond to signal changes appreciated in DWI sequences.

DWI restriction could be and additional marker of disease activity. More studies are necessary to further evaluate the use of DWI changes in MS.  These findings could be of prognostic value and prompt towards aggressive management to prevent disease progression and disability.