Proton magnetic resonance spectroscopy of the lenticular nuclei in bipolar I affective disorder.

Proton magnetic resonance spectroscopy (1H-NMS) was used to examine the ratio of choline-containing compound (Cho) to creatine (Cr) in the basal ganglia. Subjects comprised 10 bipolar I affective disorder patients and 10 healthy control subjects. No significant difference was found in the Cho/Cr, N-acetyl-aspartate (NAA)/Cr, or NAA/Cho ratios between bipolar patients and control subjects. Within the bipolar group, negative correlations emerged between the NAA/Cr ratio in the right lenticular nuclei and both age at onset and age at the time of study. The results suggest that a late onset of illness and older age are associated with neuronal cell loss in the right lenticular nuclei in bipolar patients.