MRI Patterns in Term Perinatal Hypoxic–Ischemic Brain Injury

A practical radiology review of MRI Patterns in Term Perinatal Hypoxic–Ischemic Brain Injury, focused on imaging findings, differential diagnosis, reporting points, and high-yield teaching pearls.

Background

• HIBI → major cause of neonatal encephalopathy & later CP
• MRI = key retrospective medicolegal biomarker

Patterns differ by severity & timing of insult

Pathophysiology

• 》Primary energy failure → Na/K-ATPase failure → cytotoxic edema
• 》Excitotoxicity (GLU/NMDA) → apoptosis
• 》TNF-α → necroptosis
• 》3 stages: primary → latent reperfusion → secondary/tertiary delayed injury

Classification logic

• Perfusion failure pattern reflects autoregulation capacity
• Term infants → high-metabolic “central” structures or watershed zones