新生儿低血糖脑损伤的MRI表现

目的 初步探讨新生儿低血糖脑损伤的MRI表现特征及扩散加权成像(DWI)存早期发现低血糖脑损伤中的应用价值.方法 回顾性分析12例低血糖新生儿(其中10例诊断为新生儿低血糖脑病)MRI资料,12例患儿于出生后3至10 d内进行了头部MR扫描,包括常规T1 WI、T2、WI 和DWI扫描.其中4例在第一次检杏后7至10 d后再次行MR扫描.结果 12例首次DWI检查中11例出现异常高信号,受累脑区包括双侧枕叶皮层2例、右侧枕叶皮层1例、左侧枕叶皮层及皮层下1例,双侧枕叶皮层及皮层下2例、双侧顶枕叶皮层2例、舣侧顶枕叶皮层及皮层下2例、胼胝体压部4例、双侧放射冠2例、左侧尾状核及苍白球1例、舣侧背侧丘脑1例、双侧内囊后肢1例.12例首次常规T1 WI、T2 WI中,4例T1 WI呈现异常信号,表现为受累部位皮层T1信号减低3例、受累的双枕叶皮层稍短T1信号1例;5例T2 WI见异常信号,均表现为受累部位皮层及皮层下T2信号稍增高且灰白质分界不清.4例复查中,受累枕叶局部白质软化4例,残存枕叶皮层见条状稍高T1信号2例,双侧大脑半球白质呈弥漫性脱髓鞘改变1例,胼胝体压部T2高信号消失1例,胼胝体压部仍见稍高T2信号1例.结论 在新生儿期,可能和低血糖相关的腑拟伤多发生在双侧顶、枕叶后部脑组织.早期的DWI扫描有助于低血糖脑损伤的早期发现和评估.

MRI findings of brain damage due to neonatal hypoglycemia

Objective To report the MRI findings of brain damage obsenrved in neonatal patients who suffered from isolated hypoglycemia and to explore the value of diffusion-weighted imaging(DWI) inearly detection of neonatal hypoglycemic brain iniun,. Methods Twelve neonates with isolated hypoglycemia(10 of the 12 were diagnosed to suffer from hypoglycemic encephalopathy)were enrolled in this study.They were first scanned at age from 3 days to 10 days with Tl WI,T,WI and DWI(b is 0 s/mm2,1000 s/mm2),and 4 of them were then scanned from 7 days to 10 days following the initial scan.All acquired MR images were retrospectively analysed.Results First series of DWl images showed distinct hyperintense signal in 11 cases in several areas including bi lateral occipital cortex(2 cases),right occipital cortex(1 case),left occipital cortex and subcortical white matter(1 case),biIateral occipital cortex and flubcortical white matter(2 cases),bilateral parieto-occipital cortex(2 cases),bilateral parieto-occipital cortex and subcortical white matter(2 cases),the splenium of corpus catlosum(4 cases),bilateral corona radiata(2 cases),left eaudate nucleus and globus pallidus(1 case),bilateral thalamus(1 case),bilaterally posterior limb of internal capsule(1 ease).In the initial T1 WI and T2,WI images,there were subtle hypointensity in the damaged cortical areas(3 cases),hyperintensity in the bilaterally affected occipital cortex(1 case)on T1 weighted images,and hyperintensity in the affected cortex and subcortieal white matter with poor differentiation on T2 weighted images.The followed-up MRI of 4 cases showed regional encephalomalaeia in the affected occipital lobes(4 cases),slightly hyperintensity on T2 weighted images in the damaged occipital cortex(2 cases),extensive demyelination(1 case).disappearance of hyperintensity of the splenium of corpus callosum(1 case),and persistent hyperintensity in the splenium of corpus callosum (1 case)on T2 weighted images.Conclusion The findings suggest that posterior parieto-occipital regions are most frequently injured in neonatal period due to severe hypoglycemia.DWI is a useful technique in the early detection and evaluation of hypoglycemic brain injury of neonates.