Demyelination vs. Tumor Infiltration in the Brainstem

Differentiating brainstem demyelination from tumor infiltration is a common diagnostic challenge. Both disease processes involve subacute onset of symptoms (typically, a mix of cranial neuropathies and long-tract signs) and produce similar findings on conventional magnetic resonance imaging (MRI; e.g., abnormal T2 hyperintensity with variable contrast enhancement). In the absence of diagnostic clues from cerebrospinal fluid analysis or other ancillary testing, brainstem biopsy, although risky, may be considered to avoid a delay in initiation of appropriate treatment. In this study, researchers evaluated the ability of brainstem diffusion tensor imaging (DTI) to distinguish between demyelination and tumor infiltration when other evidence is …