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Updated: Aug 4, 2026
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Double Direct Injection of Blood into the Cisterna Magna as a Model of Subarachnoid Hemorrhage
Published on: August 30, 2020
Cisterna magna clot and subsequent post-hemorrhagic hydrocephalus
1Department of Diagnostic Imaging, Janeway Child Health Center and Memorial University, St John's Newfoundland, Canada. hcc.crabe@hccsj.nf.ca
Pediatric Radiology
|April 12, 2001
Summary
Clot in the cisterna magna (CM) significantly increases the risk of posthemorrhagic hydrocephalus (PHH) in premature infants. Identifying CM clot on initial ultrasound is a better predictor of PHH than initial hydrocephalus findings.
Area of Science:
- Neonatal neurology
- Pediatric neurosurgery
- Medical imaging in neonates
Background:
- Posthemorrhagic hydrocephalus (PHH) is a serious complication of intraventricular hemorrhage (IVH) in premature infants.
- Previous research linked intraventricular clot to PHH, but the impact of cisterna magna (CM) clot was unknown.
Purpose of the Study:
- To investigate if CM clot on initial cranial ultrasound predicts the development of PHH in neonates with IVH.
Main Methods:
- Retrospective review of ultrasound records from 41 neonates with at least grade 2 IVH.
- Prospective performance of specific CM views during initial cranial ultrasounds.
Main Results:
- 22 (61%) neonates developed hydrocephalus; 21 (58%) had CM clot identified on initial ultrasound.
- CM clot significantly increased PHH risk (OR 16.5) and need for intervention (OR 28.0).
- Symmetric intraventricular clot (>50%) and dilated third ventricle (> or = 8 mm) also predicted hydrocephalus.
Conclusions:
- Cisterna magna clot is a significant predictor of PHH in premature infants.
- CM clot is a more potent predictor of PHH than initial hydrocephalus assessment.
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