Prediction of persistent ventricular dilation by initial ventriculomegaly and clot volume in a porcine model

Abstract

OBJECTIVE While intraventricular hemorrhage (IVH) is associated with posthemorrhagic ventricular dilation (PHVD), not all infants affected by high-grade IVH develop PHVD. The authors aimed to determine clot-associated predictors of PHVD in a porcine model by varying the amount and rate of direct intraventricular injection of whole autologous blood. METHODS Seven 1-week-old piglets underwent craniectomy and injection of autologous blood into the right lateral ventricle. They survived for a maximum of 28 days. MRI was performed prior to injection, immediately postoperatively, and every 7 days thereafter. T1-weighted, T2-weighted, and susceptibility-weighted imaging (SWI) sequences were used to segment ventricular and clot volumes. Spearman correlations were used to determine the relationship between blood and clot volumes and ventricular volumes over time. RESULTS The maximum ventricular volume was up to 12 times that of baseline. One animal developed acute hydrocephalus on day 4. All other animals survived until planned endpoints. The interaction between volume of blood injected and duration of injection was significantly associated with clot volume on the postoperative scan (p = 0.003) but not the amount of blood injected alone (p = 0.38). Initial postoperative and day 7 clot volumes, but not volume of blood injected, were correlated with maximum (p = 0.007 and 0.014) and terminal (p = 0.014 and 0.036) ventricular volumes. Initial postoperative ventricular volume was correlated with maximum and terminal ventricular volume (p = 0.007 and p = 0.014). CONCLUSIONS Initial postoperative, maximum, and terminal ventricular dilations were associated with the amount of clot formed, rather than the amount of blood injected. This supports the hypothesis that PHVD is determined by clot burden rather than the presence of blood products and allows further testing of early clot lysis to minimize PHVD risk.

A robotic magnetic resonance‐guided high‐intensity focused ultrasound platform for neonatal neurosurgery: Assessment of targeting accuracy and precision in a brain phantom

“…Currently, there are no direct treatments for the blood clots caused by IVH; rather, the standard of care is the management of IVH through prevention and treatment of posthemorrhagic ventricular dilation 1 . Recently, a noninvasive treatment modality has been investigated to lyse the blood clots caused by IVH using high‐intensity focused ultrasound (HIFU) 8,9 …”

“…1 Recently, a noninvasive treatment modality has been investigated to lyse the blood clots caused by IVH using high-intensity focused ultrasound (HIFU). 8,9 HIFU is a noninvasive treatment modality that emits focused acoustic energy to produce bioeffects in tissue. 10 A spherically concave transducer causes the ultrasound waves to converge geometrically to a single focal point at a set distance.…”