Proton MRS studies in Huntington's disease

We studied six patients in the early stage of Huntington's disease, together with six unaffected normal subjects. Localized spectra were acquired from 4-ml voxels encompassing the combined putamen and caudate head using STEAM with TR=1 s and TE=40 ms. Metabolite concentrations were calculated using tissue water as an internal reference. Although MRI showed minor degenerative changes in the basal ganglia, we were unable to detect any differences in the neuronal marker,N-acetylaspartate, between the two groups (patient mean ± SD, 10.7±2.1 µmol g wet wt−1; controls 11.4±1.3). Similarly, we were unable to detect differences in either choline or creatine. In contrast to other studies, we were unable to detect any increase in lactate content of the basal ganglia in these patients with early stage disease. We conclude that proton MR spectroscopy will not be a suitable technique to detect the very early changes in asymptomatic patients identified as having the mutation.