Impaired Neurodevelopmental Outcome After Mild Germinal Matrix-Intraventricular Hemorrhage.

Germinal matrix–intraventricular hemorrhage (GMH-IVH) is a common and characteristic form of intracranial hemorrhage occurring in the premature infant. The hemorrhage originates in small blood vessels in the subependymal germinal matrix (also termed the ganglionic eminence) and may disrupt the ependymal lining and extend into the lateral ventricle. Severe IVH consists of large amounts of intraventricular blood (usually termed grade 3 IVH) and may be complicated by hemorrhagic venous infarction in the periventricular white matter (often termed grade 4 IVH) or by post–hemorrhagic hydrocephalus or both. Many studies have documented increased short-term and long-term neurologic morbidity after severe IVH. In this issue of Pediatrics, Mukerji et al report the first meta-analysis of neurodevelopmental outcomes after GMH-IVH (termed periventricular/ intraventricular hemorrhage in the report). Their review confirms previous data indicative of unfavorable outcomes after severe GMH-IVH but notably also reports impaired neurodevelopmental outcome after mild GMH-IVH. The findings raise 2 important questions: (1) the biological underpinning of the relationship between the severity of GMH-IVH and outcome, and (2) the extent to which the data should be used in counseling in the neonatal period.