Classic neuroimaging findings of nonketotic hyperglycemia on computed tomography and magnetic resonance imaging with absence of typical movement disorder symptoms (hemichorea-hemiballism).

While there are broad differential diagnoses for either the clinical finding of hemichorea-hemiballism or the imaging finding of lateralizing/asymmetric basal ganglia lesions (hyperdense on computed tomography, hyperintense on T1 magnetic resonance imaging), the presence of both findings is highly suggestive of nonketotic hyperglycemia. We present an unusual case of a patient with vague stroke-like complaints and imaging findings notable for lateralizing basal ganglia lesions. Laboratory analysis revealed nonketotic hyperglycemia and neurologic exam failed to elicit any findings of movement disorder. As far as we know, this is the first published case of a patient with typical neuroimaging manifestations of nonketotic hyperglycemia without associated hemichorea-hemiballism (a disorder of abnormal movements comprised of more proximal, higher amplitude movements-ballismus and lower amplitude, more distal movements-chorea). This finding suggests that radiologists should be alert to the possibility of nonketotic hyperglycemia in patients with asymmetric/lateralizing basal ganglia lesions even in the absence of a movement disorder.