Advanced magnetic resonance imaging in benign hereditary chorea: study of two familial cases.

No brain abnormalities are usually detected on conventional magnetic resonance imaging (MRI) in benign hereditary chorea (BHC); there are currently no studies with advanced techniques in literature. We investigated whether conventional and advanced MRI techniques could depict regional brain abnormalities in two familial BHC patients and 24 healthy controls. No brain abnormalities on conventional scans were detectable; also, no significant differences in fractional anisotropy of the basal nuclei were observed. Volumetric analysis showed a decreased volume of the striatum bilaterally compared with controls, whereas spectroscopy demonstrated a significant increased myoinositol/creatine ratio bilaterally, a reduction of choline/creatine ratio bilaterally, and of N-acetyl-aspartate/creatine in the right putamen. With the limits of the small sample size in the patient group, these data show that, despite the absence of macroscopic changes on conventional MRI, volumetric and metabolic abnormalities are present in the basal nuclei of BHC patients.