Clinical Application Research On The Differentiation And Diagnosis In Parkinson’s Disease By Functional Magnetic Resonance Imaging And Quantitative Analysis

Part I Application Research of MR DWI Imaging on Diagnosis and Differential diagnosis in multiple system atrophy, progressive supranuclear palsy and PD.Objectives:The aim of the present study was to explore the value of DWI in diagnosis and differential diagnosis among MSA, PSP and PD.Methods:MRI was performed by using a1.5-TMR imager (Philips Achieva system) and standard quadrature head coil or16-channel head/neck coil. We performed DWI sequences to27MSA patients,16PSP patients,34PD patients, and32age-and sex-matched healthy controls. Regional ADCs were measured in the middle cerebellar peduncle (MCP), pons caudal and rostral, midbrain, the superior cerebellar peduncle (SCP). globus pallidus, medulla oblongata, as well as frontal and parietal white matter in the PSP, PD and controls. The sensitivity and specificity for rADC in the MCP were calculated using a receiver operator characteristic (ROC) curve analysis between the MSA and non-MSA.Results:In MSA, the rADC values in MCP, pons rostral, pons caudal, medulla oblongata were significantly higher than in PSP, PD, and controls; Furthermore, the rADC values in midbrain were significantly higher in MSA than in controls; The rADC values in SCP were significantly higher than PD and controls. PSP group had the largest rADC in SCP, globus pallidus; The rADC values in SCP, MCP and pons caudal of PSP group were significantly higher than in PD and controls; Furthermore, the rADC values of pons caudal and MCP were significantly higher than in PD and controls. In contrast, the rADC values in globus pallidus of controls were significantly lower than in PSP, MSA, and PD. The optimal cut off level (with an area under the ROC curve of0.937) to discriminate MSA from non-MSA was an MCP rADC>0.835×103mm2/s (sensitivity of78.9%and specificity100%).Conclusion:Use rADC values to evaluate the characteristic lesions in MSA, PSP, and PD by placing ROIs can help to differentiate these disorders.Part II Application Study of Quantitative assessment the Brain Iron Content of Parkinson’s Disease in vivo by Magnetic Resonance Multi-Echo sequenceObjectives:To explore the feasibility of the brain iron distribution by quantitative study on controls using Multio-echo imaging with GRASE technique (R2quantitative analysis), and to discover the characteristic of the brain iron distribution and assess the diagnosis value of Multio-echo imaging in Parkinson’s Disease.Methods:MR imaging examinations were performed on a1.5T whole-body MR imaging system (Philips Achieva system) by using16-channel head/neck coil.31patients with PD and30age and sex-matched healthy controls underwent Multio-echo imaging using GRASE technique. The T2RT values of red nucleus (RN), substantia nigra (SN), caudate nucleus (CA), globus pallidus (GP), putamen (PU) and thalamus (THA) were measured and calculated R2value correspondingly. The regression analysis performed between the R2value in Controls and autopsy confirmed regional iron content. Group differences were assessed by R2value in the corresponding ROI with t-test.Results:In healthy controls, we found a positive correlation (r2=0.859, P=0.008) between R2value and previously autopsy comfirmed regional iron content. The straight line equation Y=4.968X-48.842(Y on behalf of the brain iron content, and X-representative tissue’s R2value). This validates the feasibility of the brain iron distribution by Multio echo imaging using GRASE technique.TheR2values were significant increased in PD than controls group in SN.Conclusion:The increased R2means the brain iron content in the SN of PD markly increased.Brain iron content can be reliable evaluated by Multio echo imaging using GRASE technique in vivo, and it have a high application value in the diagnosis and differential diagnosis of PD.Part Ⅲ Clinical Application Study of Early Diagnosis of Parkinson’s Disease by Magnetic Resonance DTI ImagingObjective:To assess the value of DTI imaging in early diagnosis of Parkinson’s disease by measuring the FA and rADC of early PD using DTI imaging.Methods:MR imaging examinations were performed on a1.5T whole-body MR imaging system (Philips Achieva system) by using16-channel head/neck coil.67subjects (33PD with early stage and34age-and gende-rmatched controls) were studied with a DTI protocol with15directions. Regions of interest (ROI) were drawn in both side of pons, middle cerebellar peduncles, superior cerebellar peduncles, substantia nigra and thalamus. Group differences were assessed by value of FA and rADC in the corresponding ROI with t-test.Results:Compared with controls, the FA of group PD in Substantia nigra was decreased with significant difference. The FA between PD group and control group in other ROIs were found no significant difference. PD group rADC decreased in superior cerebellar peduncles. When compared to the controls group, significant difference was found; but there were no significant difference in pons, middle cerebellar peduncles, substantia nigra and thalamus between PD group and control group.Conclusion:DTI can non-invasively detect the changes of FA and rADC in patients with early PD in vivo. DTI is of a high application value for providing important information in the early diagnosis of PD.