Microstructure Assessment In The Brain Of Wilson’s Disease Patients:A Diffusion Kurtosis Imaging Study

1 Objective This article aimed to detect the altered brain microstructure with an advanced technique of diffusion kurtosis imaging in Wilson’s disease, to provide effective value for the early diagosis.2 Methods In this project, a total of 35 WD patients were enrolled from Department of Neurology at the First Affiliated Hospital of Anhui University of TCM(21 males and 14 females), ranging in age from 18 to 45 years with mean age of 26.94±6.98 years, and 30 age- and sex-matched healthy volunteers were recruited. The imaging sequences were performed using a 3.0-Tesla MR system, including conventional MR sequence(T2-weighted FLAIR imaging), T1-3D BRAVO sequence and DKI sequence. Thereafter, the data were analysed with methods of manual ROI, TBSS and VBM, using program of AFNI, FSL, DKE and Matlab.3 Results ⑴ Result of manual ROI Significant difference of MD in bilateral lenticular nucleus between patients and controls was found(P<0.001), the same as MK(P<0.001), KA(P<0.001), KR(P<0.05) in the bilateral head of caudate nucleus, KA(P<0.05), MD(P<0.05) in bilateral thalamus, FA(P<0.05) in bilateral red nucleus and MK(P<0.05), FA(P<0.05) in bilteral substantia nigra.⑵ Result of TBSS TBSS maps showed decreased MK in genu, splenium and body part of the corpus callosum, bilateral anterior limb of the interal capsule, posterior limb of the interal capsule, bilateral corona radiata, bilateral superior longitudinal fasciculus and thalamus radiation in WD,( P<0.0001, FWE simulation). MK was decreased in genu, splenium and body part of the corpus callosum, left genu of the interal capsule, bilateral corona radiata, bilateral superior longitudinal fasciculus and thalamus radiation in WD,( P<0.0001, FWE simulation).⑶ Result of VBM The intergroup analysis of DKI parameters was not performed due to the failure of registration. Compared to healthy volunteers, FA was increased in the bilateral head of caudate nucleus(HCN), lenticular nucleus(LN), thalamus(THA), substantia nigra(SN), red nucleus(RN), right dentate nucleus(DN) and decreased in the thalamus and extensive white matter in WD. MD was increased in HCN, LN, STN, RN and extensive white matter in WD with FDR simulations(P=0.001, α=0.05, cluster size =326).4 Conclusions ⑴ The technique of DTI provides higher sensitivity and specificity than conventional MRI to detect the changement of brian microstructure. ⑵ Compared to DTI, the technique of DKI is more sensitive to detect the variation of brian microstructure in WD. ⑶ Lesions in basal ganglia, thalamus might disconnect the basal ganglia-thalamo-cortical circuits or DRT track and disrupt cerebello-thalamo-cortical network finally, which causes clinical extrapyramidal symptoms.