Evidence of occurrence of intradural and subdural hemorrhage in the perinatal and neonatal period in the context of hypoxic Ischemic encephalopathy: an observational study from two referral institutions in the United Kingdom.

The occurrence of subdural hemorrhage (SDH) on the convexities of the cerebral hemispheres is not an unusual finding in the setting of intrauterine, perinatal, or neonatal deaths, the hemorrhage usually presenting either as a thin film over the occipital poles or as a small infratentorial bleed. Working in 2 referral centers with over 30,000 deliveries per year, we routinely examine the dura macroscopically and histologically in nonmacerated fetuses over 24 weeks in gestation and in neonates. This paper describes our experience of intradural hemorrhage (IDH) and SDH associated with hypoxia. Our series comprises 25 fetuses and 30 neonates with obvious macroscopic intradural hemorrhage and hypoxia of varying degrees of severity diagnosed by systematic examination of the brain. Fetal gestational age ranged from 26-41/40 weeks (all no more than 24 hours from intrauterine death), while the 30 neonates lived for between 1 hour and 19 days. Simultaneously with IDH, frank SDH was seen in 2 of 3 of all cases (16 fetuses and 20 neonates). Intradural hemorrhage was more prominent in the posterior falx and tentorium, most likely because of the existence of 2 venous plexus at these sites. Our findings demonstrate that SDH and cerebral hypoxia are common associations of IDH and that SDH (often seen as a thin film ofhemorrhage) almost always occurs in association with diffuse falcine IDH. Diffuse IDH with SDH are more frequently associated with severe or moderate hypoxic ischemic encephalopathy (HIE), while mild or early HIE is more common with focal IDH without SDH.