Intracerebral Hemorrhage in the Rat: Effects of Hematoma Aspiration

Abstract

Deep intracerebral hemorrhage is associated with considerable mortality and morbidity, but the value of surgical therapy is debatable. The purpose of this study was to evaluate whether aspiration of the hematoma in a rodent model of intracerebral hemorrhage could improve final neurological outcome. Intracerebral hemorrhage was induced in 2 groups of rats by injection of bacterial collagenase into the caudate nucleus. In 1 group of rats, streptokinase was used to lyse the hematoma 4 hours after hemorrhage induction, and the clot was then aspirated. Behavioral function was evaluated repeatedly until the rats were killed 7 weeks after collagenase injection. Histology was used to assess neuronal loss, astroglial proliferation, and overall brain morphology. In a second experiment, brain water was measured at 24 hours. The treated rats performed significantly better than controls on a motor-behavior evaluation on days 1, 2, and 28 after aspiration. Skilled forelimb testing performed for 3 weeks after the global behavior evaluations showed a significant deficit of contralateral forelimb function in both groups, but there was no significant difference between the 2 groups. Neuronal loss in the perihematoma striatum was significantly greater in untreated compared with treated rats. In most rats, structural damage extended into the internal capsule and thalamus. Aspiration of the hematoma after collagenase-induced hemorrhage slightly improved acute functional outcome and reduced neuronal loss from the striatum. Further studies are required to delineate the mechanism of the effect.