新生儿低血糖脑损伤的MRI表现及鉴别诊断

The MRI manifestation and differential diagnosis of neonatal hypoglycemic brain injury

目的探讨新生儿低血糖脑损伤的MRI表现特点及其诊断价值。方法回顾性分析32例经临床确诊为低血糖脑损伤新生儿的MRI资料,常规进行1.5T MR检查,扫描序列包括T1WI、T2WI、液体衰减反转恢复(FLAIR),及扩散加权成像(DWI),扫描时间均在出生后6 d内进行。其中8例在第一次检查后(8～14)d内再次行MRI扫描。结果 32例患儿中,12例T1WI序列表现异常,受累部位9例表现为稍低信号影,3例表现为稍高信号影;21例T2WI序列表现为受累部位稍高信号影;17例FLAIR序列表现异常,受累部位10例表现为稍高信号影,7例表现为稍低信号影;32例在DWI上表现为高信号影,受累部位ADC值降低,呈低信号影。受累脑区包括双侧顶枕叶皮层及皮层下脑白质21例,胼胝体12例,放射冠区9例,双侧基底节区9例,双侧颞叶后部皮层下脑白质3例,双侧额叶后部皮层下脑白质4例,大脑半球广泛5例,内囊2例,丘脑2例。结论新生儿低血糖脑损伤以双侧顶枕叶皮层及皮层下脑白质,胼胝体,放射冠区及双侧基底节区最常受累,常对称性分布,具有一定的特征性。DWI序列较常规T1WI、T2WI、FLAIR序列在新生儿低血糖脑损伤的诊断及鉴别诊断具有明显的优势,为临床诊疗提供了有力的影像学参考依据,可以作为常规序列进行扫描。

Objective To discuss the MRI features and diagnostic value of neonatal hypoglycemic brain injury. Methods MRI data of 32 newborns diagnosed with hypoglycemic brain damage with routine 1.5 T MR examination were retrospectively analyzed. The scanning sequences included T1 WI, T2 WI, liquid attenuation inversion recovery（FLAIR）and diffusion-weighted imaging（DWI）. The scanning time was within 6 d after birth. 8 cases among all cases were scanned by MRI again in 8～14 d after the first examination.Results Among 32 children, 12 cases of T1 WI sequence were abnormal, 9 cases of the affected area were slightly lower signal shadow,and 3 cases showed slightly high signal shadow; 21 cases of T2 WI sequence showed a slight high signal shadowin the affected area; There were 17 cases of abnormal FLAIR sequence, 10 cases with high signal shadowin the affected area and 7 cases with lowsignal shadow; 32 cases showed high signal shadow on DWI, lower ADC value in the affected area and low signal shadow. The affected brain regions included 21 cases of bilateral parietal occipital cortex and subcortical white matter, 12 cases of corpus callosum, 9 cases of corona radiata,9 cases of bilateral basal ganglia, 3 cases of bilateral posterior temporal lobe subcortical white matter, 4 cases of bilateral posterior frontal subcortical white matter, 5 cases of cerebral hemispheres, 2 cases of internal capsule, 2 cases of thalamus. Conclusion The brain damage of newborn with hypoglycemia is most often affected by bilateral apical occipital cortex and subcortical white matter, corpus callosum, radiate crown area and bilateral basal ganglia, which have a symmetry distribution and characteristic. The DWI sequence has obvious advantages compared with the routine T1 WI, T2 WI and FLAIR sequences in the diagnosis and differential diagnosis of neonatal hypoglycemic brain injury. It provided a powerful imaging reference for clinical diagnosis and treatment and can be scanned as a routine sequence.