Computed Tomography of Hypoxic-ischaemic Brain Injury in Infants, Children, and Adults: Three Illustrative Cases and Literature Review

AYH Wan, JSF Shum, SSW Lo, JCK Lee, ANL Sy, CY Chu, SYJ Ka, SCS Cheng

Hong Kong J Radiol 2011;14:44-8

Global hypoxic-ischaemic injuries to the brain are devastating and result in high mortality and morbidity in both children and adults. We report three cases from different causes of hypoxic-ischaemic injury to the brain in these age-groups. Computed tomography plays an important role in the diagnosis and acute management of this condition. Diffuse hypodense changes with effacement of the cerebrospinal spaces, decreased cortical gray matter attenuation with loss of normal gray-white differentiation, the 'reversal sign' and 'white cerebellum sign' can all be discerned by computed tomography.

However, such changes can be subtle and may mimic other conditions such as subarachnoid haemorrhage and dural sinus thrombosis. Magnetic resonance imaging, including conventional T1- and T2-weighted images, diffusion-weighted imaging and proton spectroscopy are accurate and useful modalities for further evaluating hypoxic-ischaemic brain injury in cases with no overt computed tomography abnormalities. To facilitate prompt patient management, recognition of differing imaging features in infants / young children versus older children / adults is crucial for radiologists and clinicians.