Preterm brain injury: Germinal matrix-intraventricular hemorrhage and post-hemorrhagic ventricular dilatation.

Germinal matrix hemorrhage and intraventricular hemorrhages (GMH-IVH) remain a common and clinically significant problem in preterm infants, particularly extremely preterm infants. A large GMH-IVH is often complicated by posthemorrhagic ventricular dilation (PHVD) or parenchymal hemorrhagic infarction and is associated with an increased risk of adverse neurologic sequelae. The widespread use of cranial ultrasonography since the early 1980s has shown a gradual decrease in the incidence of GMH-IVH and has helped with the identification of antenatal and perinatal risk factors and timing of the lesion. The increased use of magnetic resonance imaging (MRI) has contributed to more detailed visualization of the site and extent of the GMH-IVH. In addition, MRI has contributed to the awareness of associated white matter changes as well as associated cerebellar hemorrhages. Although GMH-IVH and PHVD still cannot be prevented, cerebrospinal fluid drainage initiated in the early stage of PHVD development seems to be associated with a better neurodevelopmental outcome. Further studies are underway to improve treatment strategies for PHVD and to potentially prevent and repair GMH-IVH and PHVD and associated brain injury. This chapter discusses the pathogenesis, incidence, risk factors, and management, including preventive measures, of GHM-IVH and PHVD.