germinal matrix hemorrhage
Bleeding in the germinal matrix region of premature infant brains, a major cause of neurological morbidity.
Full Definition
Germinal matrix hemorrhage (GMH) is a type of intracranial bleeding that occurs predominantly in very premature infants, typically those born before 32 weeks gestation. The germinal matrix is a highly vascularized region near the lateral ventricles that is particularly vulnerable to fluctuations in cerebral blood flow and blood pressure. GMH is graded I through IV based on extent: Grade I (confined to germinal matrix), Grade II (intraventricular hemorrhage without ventricular dilation), Grade III (intraventricular hemorrhage with ventricular dilation), and Grade IV (periventricular hemorrhagic infarction). Higher grades are associated with increased risk of cerebral palsy, developmental delays, and post-hemorrhagic hydrocephalus.
Usage
Usage note: Often used interchangeably with intraventricular hemorrhage, though GMH is more anatomically precise.
In Context
- "Cranial ultrasound revealed Grade III germinal matrix hemorrhage with moderate ventricular dilation." — Radiology report
- "The autopsy findings included bilateral germinal matrix hemorrhage with extension into the lateral ventricles." — Autopsy report