磁共振成像和计算机断层扫描影像分度在评估新生儿缺氧缺血性脑病脑损伤程度中的价值

目的 探讨磁共振(MRI)和电子计算机断层扫描(CT)影像分度在评估足月新生儿HIE脑损伤程度中的价值.方法 35例足月HIE患儿于出生11 d内同步进行MRI及CT检查,并与临床分度进行比较.MRI主要观察和分度指标为T1WI、T2WI的异常信号灶;CT主要观察和分度指标为CT值、低密度灶、形态学情况及出血区.应用SPSS 13.0软件进行统计学分析.结果 35例足月HIE患儿MRI及CT影像分度与临床分度均有高度关连性(列联系数为0.723、0.731).HIE以临床表现为诊断标准,CT检出率为91.4%,假阴性率为8.6%,MRI检出率为100%.26例轻度HIE患儿中,临床与影像分度符合率为46.2%(CT)、61.5%(MRI);8例中度HIE患儿中,MRI检出6例、CT检出5例.在34例轻、中度HIE患儿中,MRI示2例基底核出血,发现率为5.9%;CT示9例蛛网膜下腔出血(l例合并脑室内出血),发现率为26.5%;1例重度HIE患儿MRI及CT均示多灶性出血.结论 新生儿HIE的诊断应以临床表现及临床分度为主,影像表现及分度仅作为诊断参考指征之一.MRI异常检出率较CT高,能更早检测出基底核损伤;而CT更能发现蛛网膜下腔出血.

Value of Magnetic Resonance Imaging and Computerized Tomography Image Grade on Assessing Degree of Brain Injury in Neonates with Hypoxic-Ischemic Encephalopathy

Objective To investigate the value of image grade of using magnetic resonance imaging(MRI) and computerized tomography(CT) in assessing the degree of brain injury in full-term neonates with hypoxic-ischemic encephalopathy(HIE).Methods Thirty-five full term HIE neonates had been synchronously examined by using MRI and CT in 11 days after birth,and compared with clinical grade.MRI was used to observe abnormal signal of T1-weighted images(WI) and T2WI and make image grades.CT was applied to observe CT values,low density range,morphological condition and hemorrhage condition.SPSS 13.0 software was used to analyze the data.Results There was high correlation between MRI image grade and new CT image grade and clinical grade in 35 full-term HIE infants(contingency coefficient was 0.723 and 0.731,respectively).HIE clinical diagnosis was set as a standard;therefore,CT scan had 91.4% detection rate and false negative rate was 8.6%.However,MRI had 100% detection rate.In 26 slight HIE infants,the coincident rate of image grade and cinical grade was 46.2%(CT new image grade) and 61.5%(MRI image grade).In medium HIE infants,MRI and CT scan showed that 6 and 5 infants respectively had equal image grade.In 34 HIE infants with slight or medium HIE that MRI showed 2 cases had basal ganglia hemorrhage(detection rate was 5.9%) and CT scan showed 9 HIE infants had subarachnoid hemorrhage(in which 1 case was combined with intraventricular hemorrhage),detection rate was 26.5%.In one serious HIE infant MRI and CT scan showed complex hemorrhage.Conclusions When the pediatricians make HIE diagnosis they must first consider the clinical manifestation before taking image manifestation and image grade for reference.MRI is proved to be better than CT scan in detecting brain hypoxic-ischemic injury and in detecting basal ganglia injury earlier than CT scan.However,CT scan is more sensitive in detecting subarachnoid hemorrhage.