A Clinical Study on Neonatal Intracranial Hemorrhage

Part I: Falx Image as a CT Finding of Subarachnoid Hemorrhage

Abstract

Subarachnoid hemorrhage of the newborn is known to be the most common variaty of neonatal intracranial hemorrhage, but ist difinite diagnosis is very difficult by the usual diagnostic technique.
Although computed tomographic brain scan makes is possible to know the accurate site of the intracranial hemorrhage of the newborn, especially the intraventricular hemorrhage, the CT finding of the subarachnoid hemorrhage has not been fully evaluated.
Computed tomographic brain scan was performed on twenty-five high risk newborns with suspected intracranial hemorrhage and the high density area of the falx (falx image) was seen with or without intraventricular and intracerebral hemorrhage.
1) The falx image disappeared on the follow-up CT.
2) Intracranial hemorrhage was confirmed by CSF spectrophotometry (eighteen cases).
3) Subarachnoid hemorrhage was revealed in eight autopsy cases.
From these data, it was concluded that the falx image on the computed tomographic brain scanning was of diagnostic value on subarachnoid hemorrhage of the newborn.
Although the calcification of the falx is rarely seen in the newborn period, the falx image does not always mean the subarachnoid hemorrhage. In the newborn period, hematocrit is high and brain shows diffusely of low density on the CT scanning. The combination of high hematocrit and low density of the brain may make the higher incidence of the non-hemorrhagic falx image in the newborn period.
The points of differential diagnosis of the hemorrhagic and non-hemorrhagic falx image were:
1) The hemorrhagic falx image was wide and irregular on edges. On the other hand, the non-hemorrhagic falx image was recognized as straight and regular line on the CT scanning.
2) The mean EMI unit of twenty picksels of the hemorrhagic falx image was more than 40, but that of the non-hemorrhagic falx image was less than 40.