Examining alterations in GABA concentrations in the basal ganglia of patients with Parkinson's disease using MEGA-PRESS MRS.

PURPOSE: The aim of this study was to compare the gamma-amino butyric acid (GABA) levels in the left basal ganglia (BG) of patients with Parkinson's disease (PD) to those of healthy control (HC) volunteers using proton magnetic resonance spectroscopy (1 H MRS).

MATERIALS AND METHODS: The GABA+ signal-the composite signal from GABA, macromolecules (MMs), and homocarnosine-was detected. GABA+ levels were examined in 21 PD patients and 15 age- and sex-matched HCs. 3T-1 H-MRS using the Mescher-Garwood point-resolved spectroscopy (MEGA-PRESS) sequence was performed in order to detect GABA+ levels in the left BG, and the spectra were processed using the Gannet software. Differences in GABA+ levels between the two groups were analyzed using independent t-test analysis.

RESULTS: The GABA+ levels were significantly lower (P < 0.001) in the left BG of the patients with PD (1.31 ± 0.21 i.u.) than in the left BG of the HCs (1.62 ± 0.26 i.u.).

CONCLUSION: The lower GABA+ levels in the left BG of the PD patients suggest that GABA plays an important role in the pathogenesis of PD. The reduced GABA+ levels in the PD patients may be associated with GABAergic dysfunction.