表观弥散系数在2～12岁常规颅脑MRI正常的智力障碍/全面发育迟缓患儿中的应用

Application of apparent diffusion coefficient in children aged 2-12 years with intellectual disability/global developmental delay who have normal conventional brain MRI findings

目的 探讨快速自旋回波弥散加权成像(TSE-DWI)表观弥散系数(ADC)在2~12岁常规颅脑MRI正常的智力障碍/全面发育迟缓(ID/GDD)患儿中的应用价值。方法 选择符合ID/GDD诊断标准且常规颅脑MRI正常的578例患儿及同年龄段375例正常儿童志愿者为研究对象,并收集其影像学和临床资料。所有研究对象均行颅脑TSE-DWI序列及常规序列扫描。分析正常对照组儿童各脑区不同年龄亚组、各年龄亚组不同ID/GDD程度患儿各脑区ADC值差异,社会适应行为评分(ABAS-Ⅱ)对ID/GDD患儿各脑区ADC值的影响。结果 正常对照组额颞叶白质、胼胝体、内囊、半卵圆中心、小脑齿状核、视放射、丘脑、豆状核及尾状核ADC值随年龄升高而降低(P<0.05)。各年龄组ID/GDD患儿深、浅部白质,深部灰质核团及浅部灰质4岁~组ADC值随ID/GDD程度升高而升高(P<0.05)。深、浅部白质及深部灰质核团,各ID/GDD组ADC值随年龄的升高而降低(P<0.05)。ID/GDD患儿ADC值随ABAS-Ⅱ评分升高而降低(P<0.05)。结论 ADC能反映常规颅脑MRI正常ID/GDD患儿各脑区细微结构变化,对社会适应性方面也有一定的提示作用,可为ID/GDD患儿定量诊断提供客观依据。

Objective To study the value of fast spin-echo diffusion weighted imaging (TSE-DWI) apparent diffusion coefficient (ADC) in children aged 2-12 years with intellectual disability (ID)/global developmental delay (GDD) who have normal conventional brain MRI findings. Methods A total of 578 children with normal conventional brain MRI findings who met the diagnostic criteria for ID/GDD and 375 normal children were enrolled. Their imaging and clinical data were collected. All children underwent scanning with brain TSE-DWI sequence and routine sequence. ADC values of each brain region were compared between normal children with different ages, as well as between children with different degrees of ID/GDD in each age group. The influence of Adaptive Behavior Assessment System-II (ABAS-II) score on ADC values of each brain region was analyzed. Results For the normal children, the ADC values of the frontal and temporal white matter, the corpus callosum, the inner capsule, the centrum semiovale, the cerebellar dentate nucleus, the optic radiation, the thalamus, the lenticular nucleus, and the caudate nucleus gradually decreased with age (P<0.05). ADC values of the deep white matter, the shallow white matter, the deep gray matter nuclei, and the shallow gray matter increased with the increase in the degree of ID/GDD in the ID/GDD children aged 4-6 years (P<0.05). In the children with ID/GDD, the ADC values of the deep white matter, the shallow white matter, and the deep gray matter nuclei decreased with age (P<0.05). The ADC values of the children with ID/GDD decreased with the increase in ABAS-II score (P<0.05). Conclusions ADC can reflect the subtle structural changes of brain regions in children with ID/GDD who have normal conventional brain MRI findings. It may be associated with social adaptation. It can provide an objective basis for the quantitative diagnosis of ID/GDD in children.