The Study Of CMRI And Diffusion Tensor Imaging In Amyotrophic Lateral Sclerosis On3.0T MR

Objective: To investigate the value of cMRI and diffusion tensorimaging (DTI) in the diagnosis of amyotrophic lateral sclerosis (ALS).Methods: According to El Escorial diagnostic standard, we selected14patients with ALS as patient group and11age-matched and sex-matchedhealthy volunteer_s as control group. All subjects were performed with axialT1WI-FLAIR, FSE-T2WI, T2WI-FLAIR and DTI sequences on3.0T MRsystem. The anatomic structure and signal characteristic were observed,bilateral precentral gyrus, postcentral gyrus, subcortical white of precentralgyrus, subcortical white of postcentral gyrus, centrum ovale, corona radiata,periventricular white matter, genu of corpus callosum, splenium of corpuscallosum, posterior limb of internal capsule, cerebral peduncle, pons andmedulla pyramids were regarded as the region of interest (ROI), fractionalanisotropy (FA), relative anisotropy (RA), anisotropy index (AI), averagediffusion coefficient (DC_avg) and isotropic (Iso) were measured in ROI. All theindices above were analyzed statistically and compared with duration, severity(score ALSFRS) and progress of ALS.Results:1The expression of cMRICMRI showed brain atrophy (1case in patient group,7.1%;0in controlgroup,0%; P=0.56), hyperintense signal along corticospinal tracts onFSE-T2WI/T2-FLAIR (6cases in patient group,42.9%;4cases in controlgroup,36.4%; P=0.3), hyperintense signal in bilateral subcortical white ofprecentral gyrus on FSE-T2WI/T2-FLAIR (4cases in patient group,28.6%;1case in control group,9.1%; P=0.21), linar hypointense signal along precentralgyrus on FSE-T2WI/T2-FLAIR (2cases in patient group,14.3%;0in controlgroup,0%; P=0.3), and no obvious abnormal signal (6cases in patient group, 42.9%;7cases in control group,63.6%; P=0.3).2The differences of DTI indicesCompared with control group, FA of ROI in precentral gyrus,subcortical white of precentral gyrus, subcortical white of postcentral gyrus,centrum ovale, corona radiata, periventricular white matter, genu of corpuscallosum, splenium of corpus callosum, posterior limb of internal capsule,cerebral peduncle, pons and medulla pyramids decreased in patient group(P<0.01); FA of ROI in postcentral gyrus showed decreased tendency(P=0.052); RA of ROI in precentral gyrus, subcortical white of precentralgyrus, subcortical white of postcentral gyrus, centrum ovale, corona radiata,periventricular white matter, genu of corpus callosum, splenium of corpuscallosum, posterior limb of internal capsule, cerebral peduncle, pons andmedulla pyramids decreased in patient group (P<0.01); AI of ROI inprecentral gyrus, subcortical white of precentral gyrus, subcortical white ofpostcentral gyrus, centrum ovale, corona radiata, periventricular white matter,genu of corpus callosum, splenium of corpus callosum, posterior limb ofinternal capsule, cerebral peduncle, pons and medulla pyramids decreased inpatient group (P<0.01); DC_avgof ROI increased in precentral gyrus,postcentral gyrus, subcortical white of precentral gyrus, subcortical white ofpostcentral gyrus, centrum ovale, corona radiata, periventricular white matterand posterior limb of internal capsule (P<0.01), and increased in genu ofcorpus callosum (P<0.05); Iso of ROI decreased in postcentral gyrus andmedulla pyramids (P<0.01), in corona radiata, cerebral peduncle and pons(P<0.05).3The percentage of DTI indicesCompared with control group, FA decreased36.5%, RA decreased40.9%,AI decreased61.3%, DC_avgincreased11.0%and Iso decreased14.4%incorona radiata of patient group.4The sensitivity of DTI indicesThe sensitivities of all DTI indices were between53.6%and100%; Allthe sensitivities of FA, RA and AI showed100%, DC_avgshowed80.8%and Iso showed71.4%in corona radiata, both FA and RA showed sensitivity above80%in10ROIs and AI in8; The sensitivities of FA, RA and AI in centrumovale, corona radiata and periventricular white matter showed100%.5The specificity of DTI indicesThe specificities of DTI indices were between55.0%and83.3%; thespecificity of DTI indices showed FA76.2%, RA72.7%, AI68.2%, DC_avg63.6%in posterior limb of internal capsule; both FA and RA showedspecificity above60%in11ROIs, AI and DC_avgin6.6The correlation of DTI indices with clinical indicesDC_avgin centrum ovale had negative correlation with disease duration(r_s=-0.722, P<0.01), positive correlation with rapidity of disease progression(r_s=0.645, P<0.01), in patient group, and no correlation with age (r_s=-0.239,P=0.339) and ALSFRS (r_s=-0.330, P=0.181). FA, RA and AI had nocorrelation with age, disease duration, ALSFRS and rapidity of diseaseprogression (P>0.05).Conclusions:1CMRI wasn't sensitive enough in patients of ALS;2In both motor regions and extramotor regions in CNS, FA, RA, AI, DC_avgand Iso showed differences in patient group than that in control group;3In DTI, the changes of RA and AI were more obvious, RA was more stablethan AI;4Many indices of DTI showed higher sensitivity and specificity in ALSpatients, in different ROIs the sensitivities and specificities were different;5DC_avgin centrum ovale had negative correlation with disease duration,positive correlation with rapidity of disease progression.