Clinical and Magnetic Resonance Imaging Features of Reversible Splenial Lesion Syndrome in Adults: A Small Case Series

Background: To study clinical and magnetic resonance imaging (MRI) features of reversible splenial lesion syndrome (RESLES) in adult patients. Methods: A retrospective analysis was performed using clinical, cerebrospinal fluid (CSF), laboratory results, and neuroimaging data obtained from 6 adult RESLES patients. Results: All 6 patients (3 male cases, 3 female cases) were determined to be acute or subacute onset, most of them associated with infection or fever. All initial MRI data exhibited splenium of corpus callosum lesions with hypointensity on T1WI, hyperintensity on T2WI, diffusion-weighted imaging (DWI) and Flair, without significant gadolinium enhancement. Five patients were treated with glucocorticoids and showed significant improvement in 1-15 days, with the lesion having disappeared or weakened, and one case was lost of follow-up. The cell number and protein amount in CSF were determined to be at normal levels, or slightly increased in 3 patients with thyroid dysfunction. Conclusion: The etiology of adult RESLES was observed to be complex and diverse, primarily related to infection, fever, and thyroid dysfunction. DWI was found to be more sensitive in these lesions, and CSF cytology was observed to be either normal or mildly abnormal. A majority of patients were found to be sensitive to glucocorticoid, and have a good prognosis with lesions that disappeared rapidly.