Intracranial Hemorrhage In Utero
Fetal intracranial hemorrhage has rarely been observed. Such hemorrhage usually originates from germinal matrix with rupture into the ventricles. This may be due to the extreme capillary permeability of the vascular germinal matrix, which makes it susceptible to hemorrhage and often related to maternal factors, such as preeclampsia, or bleeding disorders. Germinal matrix or intraventricular hemorrhage is commonly classified in four grades as follows: Grade I: limited to subependymal matrix, Grade II: intraventricular extension, but without ventriculomegaly, Grade III: intraventricular extension, with ventriculomegaly, Grade IV: intraparenchymal extension.
Incidence: About 1 in 1000 pregnancies, very common in premature infants following delivery, may be as high as 40% among infants of <32 weeks.
- The sonographic appearance varies with the location, size, and age of hemorrhage.
- An echogenic clot filling the ventricles followed by ventriculomegaly. Once the hemorrhage resolves, only ventriculomegaly may be evident.
- Hydrocephalus with mixed echogenic debris layering within the ventricles.
- Large hemorrhages may produce a marked mass effect.
- Subdural hematomas appear as echogenic or complex fluid collections just beneath the cranium, displacing and distorting the brain.
- Occasionally, mixed echogenic, enlarged choroid plexus results from hemorrhage into the choroid plexus.
- Porencephalic cyst following the hemorrhage may be seen.
- Mostly occurs in the beginning of the third trimester of pregnancy.
- The primary differential diagnosis includes intracranial neoplasm or infection.
- MRI is helpful for differentiating intracranial echogenicities suspected of hemorrhage.
Associations: No specific anomaly.
Prognosis: Depends on the extent of hemorrhage and intraparenchymal hemorrhage. The outcome is usually poor, especially for those fetuses affected by higher-grade intraventricular hemorrhages, whereas it is better in the subgroup with intraventricular hemorrhage.