[How early and how specifically can hypoxic-ischemic brain lesions be detected with diagnostic imaging?]

Pathogenic events affecting the developing brain cause malformations or lesions, the pattern of which depend on the stage of brain development. While in the past diagnosis of these patterns was made by post mortem examinations, today advances of brain imaging allow this already during life time. The patterns of hypoxic-ischemic brain injuries on magnetic resonance imaging (MRI) are well known for the older child (after progress of myelination). This paper addresses the question how early and how specific these patterns can be recognized by two imaging methods, e.g. cranial ultrasound and magnetic resonance imaging. It concludes, that neonatal MRI but also neonatal ultrasound can reliably detect major lesions but may fail in the detection of less extensive patterns. Most authors therefore conclude, that a routine use of MRI for the detection of hypoxic-ischemic lesions during the neonatal period is not recommended and should rather be reserved for later controls.