[Role of cerebral computed tomography in the evaluation of brain injury following hypoxia in neonates]

Abstract

Objective: To investigate the role of cerebral computed tomography (CT) in the evaluation of the severity of brain injury following hypoxia in neonates.

Methods: A total of 114 full-term newborns who had perinatal hypoxia, including 25 cases of hypoxic-ischemic encephalopathy (HIE), 36 cases of neonatal asphyxia and 53 cases of simple intrauterine fetal distress, were enrolled in this study. Twenty normal newborns served as the Control group. All had cerebral CT scan at 2-7 days of age. Neonatal behavior neurological assessment (NBNA) was performed at 5 days of age.

Results: The average NBNA scores were significantly lower and the abnormality rate of NBNA was significantly higher in the HIE group than in the other three groups (P < 0.05). The Asphyxia and the Distress groups had also lower NBNA scores and higher abnormality rate of NBNA than the Control group (P < 0.05). Twenty-two patients were found to have cerebral CT abnormality in the HIE group, but there was only 1 case in the Control group (P < 0.01). The abnormality rate of cerebral CT in the Asphyxia and the Distress groups was not statistically different from that of the Control group. Twenty-five cases of HIE were divided into mild (n=15), medium (n=6) and severe (n=4) by clinical grading but were divided into normal (n=3), mild (n=10), medium (n=7) and severe (n=5) by CT grading. CT and clinical grading on HIE was not consistent. The sensitivity of CT in the diagnosis of mild, moderate and severe HIE was 47%, 33% and 50% respectively, the specificity was 70%, 74% and 86% respectively and the accuracy was 48%, 64% and 80% respectively.

Conclusions: CT evaluation on mild brain injury induced by asphyxia or intrauterine fetal distress is not of any value and the role of CT evaluation on the HIE grade is uncertain and doubtful.