~1H-MRS in observation of metabolism of medulla oblongata and substantia nigra in Parkinson disease

Objective To investigate the metabolic changes in medulla oblongata and unilateral substantia nigra of Parkinson's disease with 1H-magnetic resonance spectroscopy(1H-MRS),and to observe their correlation with clinical conditions of Parkinson disease(PD) patients.Methods Totally 17 PD patients(PD group) and 17 healthy subjectd(control group) were enrolled.Philips 1.5T MRI scanner was used.The medulla oblongata(MO) and the unilateral substantia nigra(SN) were selected as ROI.N-acetyl aspartate(NAA),Choline(Cho),creatine(Cr) peak area and calculated NAA/Cr and Cho/Cr ratio were obtained.Results No significant difference was observed between the PD and control groups for NAA/Cr and Cho/Cr in MO and SN.There was no obvious correlation between metabolite ratios(NAA/Cr and Cho/Cr) with clinical indexes in MO.For SN,NAA/Cr and Cho/Cr ratios in PD patients showed significant negative correlation with UPDRS score(r=-0.686,P=0.007;r=-0.770,P=0.002) and UPDRS motor score(r=-0.724,P=0.004;r=-0.843,P0.001).The NAA/Cr,Cho/Cr ratio had significant negative correlation with HY classification(r=-0.697,-0.715,P=0.012,P=0.009) in SN.Conclusion 1H-MRS can not be used as a tool for early diagnosis of PD.Metabolites changes in unilateral substantia nigra can reflect the progress of PD.