A case of diabetic hemichorea with petechial hemorrhage in the striatum

Investigations by T2-weighted MRI and MRS

Abstract

A 65-year-old woman was admitted to our hospital with chorea in her right arm and leg. Neurological examinations showed mild right hemiparesis and hemichorea. The blood glucose level was 123 mg/dl, glycosylated hemoglobin Alc 15.2 mmol/l, and plasma osmotic pressure 297 mOsm/kg. Brain CT demonstrated high density and magnetic resonance (MR) showed a high signal intensity on T1-weighted images, low signal intensity on T2-weighted images and FLAIR images, partly low signal intensity on T2-weighted images, and mildly low signal intensity on diffusion weighted images in the left striatum. Proton MR spectroscopy revealed for the left putamen a decreased N-acetyl aspartic acid/Crea ratio (0.96), normal Colin/Crea ratio (1.19), and not a rise of lactic acid. ¹²³I-IMP SPECT showed normal blood flow. The patient's diabetes was controlled with insulin, and the hemichorea improved on treatment with haloperidol at 3 mg and clonazepam at 0.5 mg per day. The MRI and MRS findings in our patient suggested petechial hemorrhage, although gliosis has been reported in biopsy and autopsy cases. The striatal hyperactivity may have been associated with the onset of hemichorea in our patient.