What are the characteristic MRI findings of hypoxic-ischemic encephalopathy in preterm infants less than 26 weeks of gestation?

In preterm infants less than 26 weeks, hypoxic-ischemic encephalopathy typically presents with periatrial white matter injury, characterized by a lack of gliosis and ex vacuo ventricular enlargement. Key diagnostic features include diffuse white matter signal abnormalities on T2-weighted MRI. Clinically, these findings are crucial as they may lead to motor and cognitive impairments. A common pitfall is confusing these changes with congenital infections, which often show calcifications.