Isolated Paravermal Hyperintensities in Neuronal Intranuclear Inclusion Disease

A 69-year-old woman without a remarkable family history presented with a 5-year history of dizziness and gait difficulty. Neurologic examinations revealed saccadic eye movement and mild limb and truncal ataxia. She had tremor, hyporeflexia, and miosis. Fluid-attenuated inversion recovery images showed isolated bilateral paravermal hyperintensities1 (Figure). Skin biopsy demonstrated eosinophilic intranuclear inclusions positive for ubiquitin and p62 in the adipocytes and sweat gland cells. Expanded CGG repeats in NOTCH2NLC 2 lead to the diagnosis of neuronal intranuclear inclusion disease (NIID). Corticomedullary lesions are sometimes absent in the early stages of NIID and isolated paravermal hyperintensities can be the initial radiologic findings.