Combined VBM With DTI To Study White Matter Characteristic Of Parkinson Disease Patients In The Early Stage

[Objective] Voxel-based morphometry and diffusion tensor imaging based on TBSS analysis was used to examine the changes of structural brain and white matter fiber in Parkinson’s disease in the early stage(Hoehn&YahrⅠ-Ⅱ phase) to provide anatomical basis for the pathogenesis of Parkinson’s disease.[Methods] (1)There are 29 cases of PD patients in the early stage and 30 cases in control team, who have the matched data in age, sex, handedness and education level.(2)MRI part:Using the Holland PHILIPS Achieva 3.0T TX superconducting MRI scanner,8 channel phase front head circle for regular whole brain scan. The people who have organic brain disease must be excluded, and the people who have normal brain structure can in the process of magnetic resonance data acquisition, both groups have DTI and 3D T1WI data collection. (3) Data post-processing process Part one:The 3D T1 WI structural image was analyzed by voxel-based morphometry with the software of Statistical Parameter Mapping 8(SPM8) running on Matlab and we adopt two sample T test for data post-processing, when P<0.005 the difference was statistically significant. Part two:DTI analysis:We adopting the TBSS technology within FSL software to analyze all participants cerebral white matter fiber DTI related parameters, Including FA (fractional anisotropy), MD (average diffusion coefficient), AD (axial dispersion coefficient), RD (parallel diffusion coefficient).(1)Before combining the FA maps to generate mean FA image, DTI images were corrected for head motion and eddy current artifacts. Then, the mean FA image of all subjects was to construct a mean white matter tract skeleton. Individual white matter tract skeletons were transformed to the MNI space aiming to observe FA value changes of Parkinson disease in the early stage. (MD RD AD average template and skeleton diagram create ditto)(2)Record these brain area which the DTI parameters were significantly different between PD and HC (P<0.05).[Result]1、In a comparison between PD and control subjects, white matter volume was significantly reduced in right superior frontal gyrus,right middle frontal gyrus, right precentral gyrus, right cingulate cortex, left middle frontal gyrus,left inferior frontal gyrus,right inferior parietal lobule, left precuneus, right temporal lobe(superior temporal gyrus、inferior temporal gyrus),left middle temporal gyrus, left parahippocampa gyrus, right cuneate lobe,bilateral splenium of corpus callosum, midbrain. The threshold was set at p<0.005.2、In a comparison between PD and control subjects, white matter volume was significantly increase in left olfactory tract, right parahippocampa gyrus, right precuneus, left supramarginal gyrus, right cerebellum anterior lobe, left cerebellum posterior lobe.. The threshold was set at p<0.005.3、PD group white matter fiber tracts in the brain area FA values decrease is genu of corpus callosum, body of corpus callosum, splenium of corpus callosum, left inside bursa forelimb, bilateral prior to, radiation crown, on bilateral corona radiata, left thalamus after radiation unit, bilateral cingulate gyrus, the left longitudinal fasciculus.4、PD group white matter fiber tracts in the brain increased MD value is genu of corpus callosum, splenium of corpus callosum, body of corpus callosum,Dome, the left cerebral peduncle, bilateral anterior limb, handers, bilateral, bilateral front corona radiata, on bilateral corona radiata, after bilateral corona radiata, bilateral thalamus after radiation, bilateral external capsule, right side longitudinal beams, the amount left occipital fasciculus5、PD group white matter fiber tracts in the brain increased RD value is genu of corpus callosum, splenium of corpus callosum, Body of corpus callosum, Dome, the left anterior limb, bilateral front corona radiata, on bilateral corona radiata, after bilateral corona radiata, the right thalamus after radiation, bilateral external capsule, bilateral cingulate gyrus, the left vertical beam, right hook bundle.6、The FA value lower, MD、RD value increases has statistically significant areas of the brain are:corpus callosum, anterior limb of internal capsule, bilateral Anterior corona radiata, bilateral Superior corona radiata, posterior thalamic radiation.In a word, compared with control group, the PD group of extensive cerebral white matter FA values decreased, MD、RD value increases(P<0.05), the AD did not have obvious changes(P>0.05).[Conclusion]1 PD group have widespread abnormalities in cerebral white matter structure, such as volume loss, FA value reduction, MD and RD value increation. These findings suggest that there are not only morphologic defects but also microstructural changes in white matter of PD patients in the early stage.2 VBM-MRI Early-stage parkinson’s disease patients may have multiple cerebral white matter volume atrophy and compensatory increase of white matter volume.3 DTI-TBSS PD may related to abnormal characteristics of the local white matter fiber integrity, RD simple change slightly raised area may reflect the early lesions, that demyelination based, FA reduced and MD, RD prompted increased exist except demyelinating injury, but also the presence of white matter fibers derangement and density level changes may represent a further development of lesions. Changes in the value of the use of MD and RD values to reflect the PD patients may be more sensitive to white matter fiber.4 Combined VBM with DTI-TBSS analysis technique can effectively show structural changes in white matter regions, two methods complement each other Can be good for early PD pathogenesis research provides the basis of the functional neuroanatomy.