Association Between Diffusion Restriction on MRI Brain and Clinical Severity in Encephalitis

Abstract

Objective:  The relationship between disease severity in people with encephalitis and restricted diffusion on brain MRI was examined. The aim was to assess the reliability of DW sequences for the early assessment and classification of disease severity in clinical practice.

Materials & Methods:  A forward-looking observational study was performed at the Lady Reading Hospital Radiology and Neurology Units, Peshawar, Pakistan. Two hundred patients were selected, with the clinical diagnosis of encephalitis. Within 72 hours after admission, an MRI of the brain (with diffusion-weighted views) was performed for all participants. Various factors were used to assess the severity of the disease, including Glasgow Coma Scale rating, intensive care unit (ICU) stay length, mechanical breathing support requirement, and total hospital days. These clinical variables were compared with imaging features to determine the value of diffusion restriction as a predictor.

Results:  Diffusion restriction was found in 73% of patients and was significantly associated with the level of disease severity. Patients with diffusion restriction had significantly lower Glasgow Coma Scale scores and higher rates of admission to an intensive care unit, ventilator requirement, extended hospital stay, and mortality. Poor outcome was associated with involvement of the temporal lobes, the thalamus, and the insular regions.

Conclusion:  In encephalitis, restricted diffusion of the MRI proved useful in predicting the severity of the disease. Diffusion weighted sequences were found to be useful in early diagnosis to predict prognosis and also in treatment planning, particularly in resource-constrained healthcare systems such as those in Pakistan.