LOCALIZED PROTON NMR-SPECTROSCOPY IN THE STRIATUM OF PATIENTS WITH IDIOPATHIC PARKINSONS-DISEASE - A MULTICENTER PILOT-STUDY

Single voxel proton MRS was used to study brain metabolism in the stri atum of patients diagnosed with idiopathic Parkinson's disease (PD). P eak metabolite ratios in long echo time spectra were evaluated in 151 patient spectra and 97 age-matched control spectra collected at four p articipating institutions using identical hardware and clinical protoc ols. Combining data from all ages (27-83 years old) showed no signific ant difference between patient and control ratios. However, in an elde rly subset of patients (51-70 years old), a significant decrease in st riatal N-acetylaspartate (NAA)/choline (Cho) was observed. Also, a sig nificant decrease in the mean NAA/Cho ratio was observed in patients v ersus controls for patients not being treated with Sinemet (Du Pont Ph arm, Wilmington, DE) (hereafter referred to as levodopa/carbidopa). Th is result is consistent with the hypothesis that NAA may provide a rev ersible spectroscopic marker for neuronal dysfunction, although a pros pective follow-up study will be needed to confirm this. Quantitation o f MRS would be useful to exclude the possibility that a change in Cho levels affected the NAA/Cho ratios.