A Pediatric Radiology Textbook and Pediatric Radiology Digital Library
Neonatal Intraventricular Hemorrhage
Etiology: — Germinal matrix is cellular and highly vascular site where neuroblasts originate — Located in subependymal region of lateral ventricles — Consists of fragile blood vessels that are prone to hemorrhage — Greatest in extent at 23-24 weeks gestation and then gradually involutes so by 28-32 weeks is confined to caudothalamic groove and is completely involuted by 36 weeks — Is venous hemorrhage due to intrinsic fragility of germinal matrix immature microvasculature, fluctations in cerebral blood flow related to lack of autoregulation (pneumothorax, hypotension, increased CO2, infection or inflammation, IV bolus), fluctuations in venous pressure and variations in venous anatomy and genetic factors — 50% of germinal matrix hemorrhages occur on day 1, 25% on day 2, 15% on day 3 – so 80-90% of germinal matrix hemorrhage occurs by 72-96 hours
Imaging: — Grade I is subependymal bleeding confined to the germinal matrix — Grade II is germinal matrix hemorrhage and intraventricular hemorrhage without ventricular dilation and filling less than 50% of ventricular lumen — Grade III is germinal matrix hemorrhage and intraventricular hemorrhage with ventricular dilation
DDX:
Complication of periventricular hemorrhagic infarct due to large amounts of intraventricular hemorrhage
Complication of post hemorrhagic hydrocephalus of prematurity (communicating hydrocephalus) — Arachnoid granulations are poorly formed at this time — Breakdown products of blood cause mechanical obstruction, acutely from debris and chronically from granulation tissue — Takes days to weeks to develop hydrocephalus — Follow these patients to diagnose posthemorrhagic ventricular dilation and evaluate the need for intervention: 1) Ventricular index is distance between falx and lateral wall of anterior horn in coronal plane and 2) Anterior horn width is diagonal width of anterior horn measured at its widest point in coronal plane
Treatment: Ventriculoperitoneal shunt to treat communicating hydrocephalus
Clinical: Clinical signs are decreased consciousness, hypotonia, seizures, apnea, coma, decreased hematocrit — but 25% are clinically silent
Radiology Cases of Neonatal Intraventricular Hemorrhage Grade I
Coronal T1 MRI with contrast of the brain (left) shows an enhancing lesion in the right germinal matrix that is of low signal intensity on gradient echo (right). There was no evidence on hemorrhage in the lateral ventricles.
Radiology Cases of Neonatal Intraventricular Hemorrhage Grade I Presenting as a Subependymal Cyst
The diagnosis was subependymal cyst most likely due to neonatal intraventricular hemorrhage Grade I.
Radiology Cases of Neonatal Intraventricular Hemorrhage Grade II
Coronal (above left), left sagittal (above middle) and right sagittal (above right) US of the head shows a round echogenic focus in the left germinal matrix. There was also an echogenic focus in the occipital horn of the left lateral ventricle (not provided). The ventricular system was normal in size. Followup exam from 2 weeks later (below) shows interval decrease in size and cavitation of the echogenic foci in the left germinal matrix and occipital horn of the left lateral ventricle. The ventricular system is minimally increased in size.
Radiology Cases of Neonatal Intraventricular Hemorrhage Grade III
Coronal US of the brain shows increased echogenicity within the anterior horn of the left lateral ventricle with ventricular dilation (upper) and increased echogenicity within the brain parenchyma in the left anterior periventricular region and right temporal region (lower left) and in the bilateral posterior periventricular regions (lower right).
Coronal US of the brain shows echogenic material within the bilateral dilated lateral ventricles.
