Teaching NeuroImage: Honeycomb Appearance of the Basal Ganglia Suggests Biallelic Nitrilase-1 Variants

A previously healthy 37-year-old woman presented with daily headaches, episodic unsteadiness, sensation of swaying, and difficulty concentrating for 5 months.Within 5 years, she showed progressive cognitive decline (MoCA 19/30), paralleled by cerebellar ataxia and bradykinesia.Figure Brain MRI 5 Years Before, 1 Year, and 3 Years After Clinical Onset Brain MRI 5 years before (A and B), 1 year (C and D), and 3 years after clinical onset (E and F) demonstrate progressive symmetric periventricular leukoencephalopathy (outlined arrows) on FLAIR (A, C, E) and increasing honeycomb-like enlargement of perivascular spaces in the basal ganglia (filled arrows) on T2-weighted images (B, D, F).