Longitudinal study of the substantia nigra in Parkinson disease: A high-field (1) H-MR spectroscopy imaging study.
INTRODUCTION
The value of biomarkers in early diagnosis and development of therapeutics in Parkinson's disease (PD) is well established.


METHODS
We used proton magnetic resonance spectroscopy in a prospective, longitudinal study of 23 patients with early PD, naïve to dopaminergic therapy, and six age-matched healthy controls to examine the temporal changes in metabolic profile of substantia nigra over a period of 3 months.


RESULTS
N-acetyl aspartate to creatine ratio at month 3 was compared with baseline values in the PD and control groups, as well as the side-to-side difference of the ratio at baseline. By month 3, n-acetyl aspartate to creatine ratio had decreased by 4.4% in patients with PD (P = 0.024), without a concomitant change in healthy controls. The side-to-side asymmetry was significantly higher in the PD group (16.7%) vs. healthy controls (1.6%, P = 0.0024).


CONCLUSION
Estimation of change in the n-acetyl aspartate to creatine ratio appears to be a fast, quantifiable, and reliable marker of dopaminergic neuronal viability in PD.
['Seraji-Bozorgzad|Navid|N|', 'Bao|Fen|F|', 'George|Edwin|E|', 'Krstevska|Shana|S|', 'Gorden|Veronica|V|', 'Chorostecki|Jessica|J|', 'Santiago|Carla|C|', 'Zak|Imad|I|', 'Caon|Christina|C|', 'Khan|Omar|O|']
D000368:Aged D001224:Aspartic Acid D015415:Biomarkers D003401:Creatine D005260:Female D006801:Humans D008137:Longitudinal Studies D008297:Male D008875:Middle Aged D010300:Parkinson Disease D066244:Proton Magnetic Resonance Spectroscopy D013378:Substantia Nigra
substantia nigra biomarkers Parkinson's disease n-acetyl aspartate Magnetic resonance spectroscopy imaging