Diffusion-weighted imaging in neonatal cerebral infarction: Clinical utility and follow-up

We describe the clinical utility of echo-planar diffusion-weighted imaging in neonatal cerebral infarction. Eight full-term neonates aged 1 to 8 days referred for neonatal seizures were studied. Patients were followed for a m ean of 17 months with detailed neurologic examinations at regular intervals . Head computed tomography (CT) and conventional magnetic resonance (MRI) a nd diffusion-weighted images were obtained. Percent lesion contrast was eva luated for 19 lesions on T-2-weighted and diffusion-weighted images. Follow -up conventional MRIs were obtained in seven patients. The findings on diff usion-weighted imaging were correlated with CT and conventional MRI finding s as well as with short-term neurodevelopmental outcome. Four patients had focal cerebral infarctions, Four patients had diffuse injury consistent wit h hypoxic-ischemic encephalopathy. Percent lesion contrast of all 19 lesion s was significantly higher on diffusion-weighted images when compared with T-2-weighted images. In five patients, there were lesions visualized only w ith diffusion-weighted imaging. In all patients, there was increased lesion conspicuity and better definition of lesion extent on the diffusion-weight ed images compared with the CT and T-2-weighted MR images. In seven of eigh t patients follow-up imaging confirmed prior infarctions. Short-term neurol ogic outcome correlated with the extent of injury seen on the initial diffu sion-weighted imaging scans for all patients. Diffusion-weighted imaging is useful in the evaluation of acute ischemic brain injury and seizure etiolo gy in neonates. In the acute setting, diffusion-weighted imaging provides i nformation not available on CT and conventional MRI. This information corre lates with short-term clinical outcome.