Cisterna magna clot and subsequent post-hemorrhagic hydrocephalus.

BACKGROUND

Posthemorrhagic hydrocephalus (PHH) is an ominous complication of intraventricular hemorrhage (IVH) in premature infants. Previous studies have correlated lateral intraventricular clot with subsequent PHH, but there are no studies assessing the outcome of clot in the cisterna magna (CM).

OBJECTIVE

The purpose of this study was to determine if the identification of clot in the CM on the initial positive cranial ultrasound for intraventricular hemorrhage increased the risk of subsequent PHH.

MATERIALS AND METHODS

A review of ultrasound records over a 4-year period identified 41 neonates with at least grade 2 IVH who had specific CM views prospectively performed.

RESULTS

Thirty-six survived more than 3 months. Overall, 22 (61%) developed hydrocephalus. On the initial positive cranial ultrasound, CM blood was identified in 21 (58%). Of these 18 (86%) developed hydrocephalus [odds ratio (OR) 16.5, confidence interval (CI) 2.5-125.7, P < 0.001] and 14 (67%) required intervention or remained dilated (OR 28.0, CI 2.8-1265.8). All patients that required permanent shunt placement had initial CM clot (P < 0.01). Initial ventriculomegaly was not a significant predictor of subsequent hydrocephalus, but a dilated third ventricle (> or = 8 mm) was (OR 9.0, CI 1.2-103.3, P < 0.04). Asymmetric intraventricular clot filling of more than 50% was not predictive of hydrocephalus, but symmetric clot of more than 50% was (OR 10.8, CI 1.4-61.6, P < 0.01). Nine neonates had concomitant parenchymal damage with varying outcomes (three shunted, two persistent ventriculomegaly, four resolved with normal sized ventricles).

CONCLUSION

In this study CM clot significantly increased the risk and was a better predictor of posthemorrhagic hydrocephalus than initial hydrocephalus.