Application Of NM-MRI In Idiopathic Parkinson’s Disease And Its Different Motor Subtypes

Background:Parkinson’s disease(PD)is a neurodegenerative disorder,pathologically characterized by the loss of neuromelanin(NM)-containing neurons of catecholamine in the brain stem.PD patients were divided into three different movement subtypes:postural instability gait difficulty(PIGD)subtypeor and tremor dominant(TD)and Mixed PD(PDM),based on the method according to the unified Parkinson disease rating scale(UPDRS)tremor grade to rigidity grade ratio values.Recognize different subtypes of PD can help understand the underlying disease mechanisms and predict prognosis and ultimately to formulate individualized treatment plan.Through neuromelanin sensitive magnetic resonance imaging(NM-MRI)can detect intracranial substantia nigra(SNc)and locus coeruleus(LC)signal change which containing neuromelanin;However,whether these three kinds of PD subtypes’ neromelain content in the brain stem are different or not is not clear.Objective:Study the neuromelain sensitive magnetic resonance imaging(NM-MRI)characteristics in nigra and locus coeruleus of primary PD,and discusses the differential values of different subtypes of PD with NM-MRI.Methods:38 cases of clinically diagnosed idiopathic Parkinson’s disease were prospectively recruited as the case group in Hubei Clinical Research Center for Parkinson’s diesease,Xiangyang No.1 People’s Hospital,From November 2019 to February 2021.and according to the scores of UPDRS part Ⅱ、Ⅲ divide all PD patients into TD(n = 10),PIGD(n = 20)and PDM)(n = 8)three subgroups.27 cases of age and gender matched healthy people were recruited as the control group.Acquisition the clinical and MRI data of all the PD patients and healthy controls.Using the improved2 D-T1-FSE sequence for NM-MRI.I the NM-MRI,substantia nigra(SN)and locus coeruleus is relatively high,Measure and calculate the Contrast to noise ratio(CNR)and the area of the SNc in left and right side,and the Contrast to noise ratio(CNR)of the locus coeruleus.Comparing the Contrast to noise ratio(CNR)of SNc and LC,and the area of SNc,among all PD patients and healthy controls,three different subgroup groups and healthy control group,three PD subgroups,and all of the data above for all the PD patients were analyzed with the H-Y grading and course of the disease use correlation analysis.Results:1,Compared with control group,in NM-MRI,the three average signal intensity of SNc subregions in PD group were decreased significantly(P = 0.012);CNR value of each SNc subregion was also decreased respectively,but only the difference in central and middle part of the SNc with statistically significant(P = 0.011,P = 0.045),the lateral part of CNR value compared to the control group showed no significant difference(P = 0.469).Compared with control group,all of the three PD subgroup SNc CNR averages were decreased,but only average CNR of the PIGD subgroup was decreased significantly(P= 0.027),the CNR values of TD and PDM subgroups were not decreased significantly(P = 0.089,P = 0.892);in the midial part of the SNc,each subgroup CNR value has decreased,but there was no statistically significant difference(P > 0.05);Three subgroups SNC medial and lateral part of CNR value have been reduced,but only but only the middle part of TD subgroup,middle and lateral part of the PIGD subgroup are statistically significant compared with control subjects(P = 0.024,P =0.002,P = 0.004).Among three subgroups,The minimum average CNR value of all SNc subregions was TD subgroup,the maximum was PDM subgroup,the CNR value of PIGD subgroup was between the TD and PDM,but there was no statistically significant difference be observed(P >0.05).Among three subgroups,The minimum CNR value in middial part of SNc was TD subgroup,the value of PDM subgroup was highest,then PIGD group.there was no statistically significant difference between the two(P>0.05).The minimum CNR value in central part of SNc was TD subgroup,the value of PDM subgroup was highest,then PIGD group,but only between PIGD subgroups and PDM subgroup was observed statistically significantly difference(P = 0.045).The minimum CNR value in lateral part of SNc was PIGD subgroup,the value of PDM subgroup was highest then TD subgroup,but no statistically significant difference(P > 0.05).2,compared with control group,the PD group of bilateral SNc high signal area is reduced,but no significant difference(P = 0.644).Compared with the control group,TD,PIGD and PDM SNC high signal area on both sides of the three subgroups are narrow,but only PIGD subtypes of SNC,on average,high signal on both sides to have statistical significance(P = 0.002).Among Three PD subgroups between bilateral SNc average area of high signal contrast,TD subtype of SNc high signal area is the largest,the second is the PDM subtype,PIGD subtype is minimal,but there were no statistically significant difference(P > 0.05).3,compared with control group,the average PD group of bilateral LC CNR value is reduced,but there was no statistically significant difference(P = 0.728).Three subgroups CNR value comparison between LC and no significant difference(P > 0.05).Conclusion:NM-MRI can assist clinical identification of primary PD with healthy people,and probably has potential diagnostic value to distinguish different PD subtypes,provideb new evidence on different subtypes based on difference neurology.