Late radiation therapy brain abnormalities that mimic leukoencephalopathy with anterior temporal lobe cysts.

A 43-year-old man who had been treated for a craniopharyngioma with surgery and radiotherapy (33 years ago) was referred for evaluation of a sudden hemiparesis. Neuroimaging documented a brainstem cavernoma associated with basal ganglia calcifications and white matter hyperintensity near anterior temporal lobe cysts (Figures 1 and 2). Late brain abnormalities are often observed after radiotherapy for childhood intracranial tumors. Microbleeds and cavernomas are well recognized in these cases. However, bilateral anterior temporal lobe cysts are uncommon, and it is crucial to recognize these to avoid misdiagnoses, particularly when they are associated with white matter abnormalities. Differential diagnoses include hereditary disorders, infectious diseases, and dilated perivascular spaces1,2,3,4.