Hypoxic-ischemic encephalopathy (HIE) is a major cause of brain damage and neurodevelopmental abnormalities in full-term newborn infants. We are reporting the results of a study comparing cranial magnetic resonance imaging (MRI) and cranial sonography (US) in 150 neonates with suspected HIE. Magnetic resonance imaging findings were normal in 44 patients (29%); 18% of patients showed only basal ganglia (BG) brightness, 10.6% showed brightness of the BG with intracerebral hemorrhage, and 63% of patients showed additional diagnostic details. Cranial US was normal in 75 patients (50%) and showed increased periventricular echogenicity in 32%, intraventricular hemorrhage in 9%, and additional diagnostic details in 13%. There was a positive correlation between MRI studies and US (P = .013). These data suggest that US is a worthwhile modality for the diagnosis of HIE but that early MRI findings will provide additional information in many cases in the detection of cerebral intraventricular hemorrhage.