Application Of Multi-modal Brain Functional Magnetic Resonance Imaging In Parkinson’s Disease

Objective:To evaluate the diagnostic value of multi-modal brain functional magnetic resonance imaging (MRI) at varous, clinical stages of Parkinson’s disease, and try to probe into its pathogenesis.Methods:Both of 31 patients with Parkinson’s disease and 34 healthy subjects were scanned with conventional MR1, DTI,1H-MRS and SWI examination. Of them,29 PD patients and 33 healthy subjects underwent resting state functional magnetic resonance imaging. The DTI was detected to measure FA and ADC values in nigra, red nucleus, basal ganglia, frontal white matter and analyze correlation of the FA and ADC bilateral average values calculated using TBSS with MoCA, HAMD, ADL and UPDRSIII scores in 31 cases of Parkinson’s disease. We measured the levels of N-acetyl compounds (NAA), creatine plus phosphocreatien (Cr+PCr) and choline compounds (Cho) in nigra and red nucleus in all patients and healthy subjects by 1H-MRS examination. And compared NAA/Cr, NAA/Cho and Cho/Cr ratios between the patient group and healthy control group and analyzed the relationship of the ratios the MoCA, HAMD, ADL and UPDRSIII scores of all PD patients. All subjects were detected with SWI to measure nigra, red nucleus, basal ganglia, frontal white matter’s CP values. After pre-processing images in 29 cases of PD patients and 33 healthy subjects were obtained with resting state fMRl we compared difference of regional homogeneity and amplitude of low frequency fluctuation between both groups, in order to localize the area of brain dysfunction in PD patients.Results: ①The FA values in nigeria, putamen, and frontal white matter of PD group is lower than control group, the frontal white matter’s ADC values of case group is higher than control group, and the difference was statistically significant (P<0.05). The case group was divide into the early group, mid and late group in accordance with H-Y graded, FA values in the substantia nigra and thalamus ADC values were significantly different (P<0.05) in three groups, FA values in the substantia nigra decreased and thalamus ADC values increased along with disease progression. The patient group were divided according to ADL, ADC value of the globus pallidus were significantly different among these groups (P<0.05), the ADC value will increase along with the ADL score. According to HAMD Depression Scale, the case group was divided into four groups, putamen, caudate nucleus and frontal white matter ADC values were significantly different in the different groups (P<0.05), the higher ADC value along with the higher HAMD score. There was negative correlation of the FA values in frontal white matter and the ADL scores in PD patients (r=-0.498, P<0.05), while there was positive correlation of the FA values in the frontal white matter (r= 0.400), ADC values in frontal white matter (r=-0.386), and ADC values in nigra (r=-0.478) with their MMSE scores (P<0.05).②The FA values of the fiber bundles including corpus callosum, superior longitudinal fasciculus, cingulate gyrus, optic radiation, frontal lobe and temporal lobe subcortex arcuate fiber, brain stem and white matter of the internal capsule bundles in PD group were significantly lower than those in the healthy control group. The FA values of the corpus callosum, left and right superior longitudinal fasciculus, cerebellar peduncle were positively correlated with MMSE scores, the FA values of right superior longitudinal fasciculus, left corticospinal tract, left cerebellar peduncle, right corticospinal tract, cerebellar peduncle were negatively correlated with HAMD scores, the FA values of splenium of corpus callosum, left superior longitudinal fasciculus, right superior longitudinal fasciculus, were negatively correlated with the ADL scores.③In the study of 1H-MRS, NAA/Cr values and NAA/Cho values between the both sides of nigra, the NAA/Cr values and NAA/Cho values between both sides of red nucleus in the patient group were significantly different (P<0.05). According to the ADL scores, HAMD scores and MOCA scores, the patients with PD were divided into three or four groups.The NAA/Cr value and Cho/Cr values in the right substantia nigra between in patients with mild depression and without depression were significantly different (P<0.05). The NAA/Cho values in the right substantia nigra were significantly different among different groups according with MoCA scores (P <0.05). Moreover, there was correlation of H-Y grade in PD patients with the NAA/ Cho values in the right red nucleus (r= 0.-402,P<0.05), their HAMD scores with NAA /Cr values in the right nigra (r=-0.611), the NAA/Cr values in the left substantia nigra (r=-0.425), and Cho/Cr values in the right nigra (r=-0.609) (P<0.05), and MOCA scores with the NAA/Cho values in right substantia nigra (r= 0.463,P<0.05).④The CP values of thalamus and frontal white matter between both sides in controls group were significantly different (P<0.05), the CP values between both sides of the caudate nucleus and frontal white matter in patient group were significantly different (P<0.05). The CP values of the left red nucleus in patient group was higher than control group, and the difference was statistically significant (P<0.05). The patient group was divided into different groups in accordance with the ADL score, HAMD score and MMSE score. The CP values of the left nigra in the dysfunction group was lower than the ADL normal group, and the difference was statistically significant (P <0.05). The CP value of left frontal white matter in moderate depression group was lower than mild and non-depression group, and the difference was statistically significant (P<0.05). The CP values of the right globus pallidus and the left frontal white matter were statistically significant among the different groups according with MOCA score, and the CP value in severe cognitive impairment group was lowest. There was negative correlation of ADL scores in PD patients with the CP values in the left substantia nigra (r=-0.492, P<0.05), their HAMD scores with the CP value of the left frontal white matter (r=-0.915, P<0.05), and MOCA scores with the CP values in left substantia nigra (r= 0.428) and the CP values in left frontal white matter (r= 0.391), and MMSE scores with the CP values of the left frontal lobe white matter (r= 0.428, P<0.05).⑤The reduced ReHo areas in patient group was mainly located in bilateral frontal (including the prefrontal cortex, superior frontal gyrus, middle frontal gyrus), the corpus callosum and the cingulate gyrus, left middle frontal gyrus and right angular gyrus, right temporal pole, and left thalamus brainstem. The ReHo increased of patient group mainly located in the bilateral parietal regions (including the medial frontal gyrus and the central post back), both inferior parietal lobule and cuneus. The reduced ALFF areas in patient group were mainly located in the left frontal lobe, the right temporal lobe, the right side of the brain and the cerebral peduncle, pons on the right side, the right side of the cerebellum, right thalamus, corpus callosum, bilateral parietal lobule. The increased ALFF areas were mainly located in the left medial frontal gyrus and the central post back, the left insula, putamen and the left side of the left thalamus. Conclusion:The multi-modal brain functional magnetic resonance imaging can be used to study the brain function, metabolism and micro-structure in patients with PD. It could help to identify the pathogenesis of PD, especially about those non-motor symptoms. It might be helpful to early diagnosis of PD.