IVH occurs when small, fragile vessels in the subependymal germinal matrix bleed. The
hemorrhage may extend either into the ventricular space and/or the surrounding
parenchyma of the lateral ventricle. The germinal matrix is adjacent to lateral ventricles
and the site of neuronal and glial cell production and subsequent migration; it is a highly
vascular area that involutes by 36 weeks gestation. IVH can occur in term infants; most
originate from choroid plexus and are generally benign.
Classification of IVH (Papile classification)
Grade I: subependymal germinal matrix hemorrhage
Grade II: IVH without ventricular dilatation
Grade III: IVH with ventricular dilatation (blood fills >50% of the ventricle)
Grade IV: IVH with extension into parenchyma (Parenchymal hemorrhage in the
absence of IVH may be classified as a Grade IV)
The infant’s degree of prematurity is the primary risk factor that supersedes all other
risks. Other factors include presence of PDA, rapid shifts in blood pressure, PaO2 or
PCO2, HIE, hypertonic infusions (glucose, bicarbonate), exchange transfusions,
hypoxia, DIC.
Head ultrasound is the main diagnostic modality and classification is based on this
modality of detection. The ultrasound probe is placed over the anterior fontanel.
Subarachnoid hemorrhages or secondary parenchymal injuries may be difficult to
detect. CT or MRI may be used to clarify findings.