Teaching NeuroImages: Corpus callosum splenium hyperintensity in fragile X–associated tremor ataxia syndrome

We present 2 patients with genetically proven symptomatic fragile X-associated tremor ataxia syndrome (FXTAS), one 62-year-old man with progressive action tremor and one 74-year-old man with progressive ataxia, showing typical middle cerebellar peduncle hyperintensities on MRI fluid-attenuated inversion recovery sequences associated with a hyperintensity of the inferior part of the splenium of the corpus callosum (figure). Splenial hyperintensity has been reported as frequently encountered and proposed as an additional radiologic diagnostic criterion in FXTAS.1,2