扩散峰度成像评估复发缓解型多发性硬化正常表现脑白质微结构变化

Evaluation of microstructure changes in normal appearing white matter of relapsing remitting multiple sclerosis by diffusion kurtosis imaging

目的采用扩散峰度成像(diffusion kurtosis imaging,DKI)评估复发缓解型多发性硬化(relapsing remitting multiple sclerosis,RRMS)正常表现脑白质微结构变化。方法对24例RRMS患者(RRMS组)及28例健康志愿者(对照组)进行DKI扫描,获得DKI相关参数,测量额叶、顶叶、枕叶、颞叶白质、胼胝体膝部、胼胝体压部、内囊前后肢,包括FA(fractional anisotropy),MD(mean diffusivity),DR(radial diffusivity),MK(mean kurtosis)及KA(axial kurtosis)值,进行比较分析。结果与健康对照组相比,RRMS患者额叶(0.39±0.06)、顶叶(0.40±0.05)、枕叶(0.43±0.07)、颞叶(0.42±0.06)白质及内囊后肢(0.69±0.04)FA值明显降低(P<0.05),而额叶[(0.97±0.08)μm^(2)/ms]、顶叶[(0.93±0.08)μm^(2)/ms]白质、内囊前肢[(0.95±0.10)μm^(2)/ms]、内囊后肢[(0.91±0.05)μm^(2)/ms]MD值显著升高(P<0.05),内囊前肢(0.89±0.09)、内囊后肢(1.13±0.11)MK值显著降低(P<0.05),额叶[(0.76±0.09)μm^(2)/ms]、顶叶[(0.73±0.07)μm^(2)/ms]、颞叶[(0.77±0.08)μm^(2)/ms]白质、内囊前肢[(0.58±0.06)μm^(2)/ms]、内囊后肢[(0.47±0.05)μm^(2)/ms]DR值及顶叶(0.95±0.07)白质MK值显著升高(P<0.05),额叶(0.74±0.07)、枕叶(0.71±0.06)、颞叶(0.65±0.06)白质及内囊前肢(0.65±0.06)、内囊后肢(0.57±0.06)、胼胝体膝部(0.48±0.05)、胼胝体压部(0.46±0.07)KA值显著降低(P<0.05)。结论DKI可评估RRMS正常表现脑白质微结构的变化。

Objective To investigate the microstructural changes of normal appearing white matter in relapsing-remitting multiple sclerosis(RRMS)by diffusion kurtosis imaging(DKI).Methods DKI measurement was performed on 24 RRMS patients and 28 healthy volunteers using a 3 T MRI scanner.DKI derived parameters,including fractional anisotropy(FA),mean diffusivity(MD),radial diffusivity(DR),mean kurtosis(MK)and axial kurtosis(KA),were obtained for each subject correspondingly within multiple regions of interest in the frontal lobe white matter,parietal lobe white matter,occipital lobe white matter,temporal lobe white matter,splenium of corpus callosum(SCC),genu of corpus callosum(GCC),anterior limb of internal capsule(ALIC),and posterior limb of internal capsule(PLIC).Results Compared to healthy controls,FA values of white matter in frontal lobe and parietal lobe,occipital lobe,temporal lobe and posterior limb of internal capsule(PLIC)were significantly decreased In RRMS patients.However,MD values of white matter in frontal lobe,parietal lobe and anterior limb and posterior limb of internal capsule were increased significantly.MK values of anterior limb and posterior limb of internal capsule was significantly decreased.DR values of white matter in frontal lobe,parietal lobe,temporal lobe,anterior limb and posterior limb of internal capsule and MK value of parietal lobe white matter were increased.KA values of white matter in frontal lobe,occipital lobe,temporal lobe,anterior limb and posterior limb of internal capsule,splenium of corpus callosum(SCC)were significantly decreased.Conclusion DKI derived parameters have demonstrated the capability to assess the microstructural changes of normal appearing white matter in RRMS.