Rabies Diagnosis: MR Imaging

Abstract

© 2014 Elsevier Inc. All rights reserved. In vivo magnetic resonance imaging (MRI) techniques provide clues for the differential diagnosis of rabies and other encephalitides. Clinical status of the subjects, conscious or comatose, must be taken into account. Blood brain barrier (BBB) integrity and lesional extent can vary accordingly. Subtle brain MR abnormalities in symmetrical distribution, however, preclude its use as a confirmatory diagnostic test. Quantitative advanced MRI techniques, such as voxel-based morphometric diffusion tensor imaging (DTI) based on whole-brain probabilistic tractography maps in assessing mean diffusivity (MD), and fractional anisotropy (FA) values, have been introduced to study evolving disease processes, particularly during the non-comatose phase. Iron imaging of the brain, albeit conventionally used for detecting hemorrhage, may be potentially useful in tracking inflammatory reactions.