Nonketotic hyperglycemic hemichorea: white shadows on CT and T1-weighted MRI

Nonketotic hyperglycemic hemichorea (NHH) is a rare movement disorder, most commonly observed in elderly female patients with poorly controlled diabetes. We describe a 55-year-old male patient with diabetes who was admitted due to involuntary movements of the right limbs for five days. CT revealed a hyperdense lesion in the left putamen and caudate nucleus, while MRI showed hyperintensity on T1WI and hypointensity on both T2WI and diffusion-weighted imaging. The patient was treated with oral haloperidol and insulin for blood glucose control, leading to gradual symptom improvement. Follow-up imaging showed resolution of the lesions, correlating with clinical improvement. NHH has characteristic imaging findings and should be differentiated from cerebral hemorrhage, basal ganglia calcification, and hepatic encephalopathy.