Sonographic ventriculography: a new potential use for sonographic contrast agents in neonatal hydrocephalus.

BACKGROUND AND PURPOSE Sonographic identification of communicating and noncommunicating forms of posthemorrhagic hydrocephalus can be difficult. This study evaluates the feasibility of using sonographic contrast agents to determine ventricular patency in a newborn animal model.

METHODS A craniotomy was performed and a catheter was placed under sonographic guidance into the lateral ventricle in five anesthetized newborn piglets. Sonograms were obtained before and after intraventricular injection of 0.01 mL of a sonographic contrast agent (Imagent, formulation AF0150; Alliance Pharmaceutical Corp, San Diego, CA) diluted in 1 mL normal saline, and images were assessed for presence and location of echogenic contrast material.

RESULTS Flow of contrast material was identifiable from the ipsilateral lateral ventricle into the contralateral lateral ventricle, and through the third and fourth ventricles into the basal cisterns during real-time sonography in every animal. Ventricular and cistern echogenicity remained increased for approximately 4 minutes after injection.

CONCLUSION Contrast-enhanced sonographic ventriculography has the potential to identify patency of CSF pathways in newborns with hydrocephalus and an indwelling ventricular catheter.