An Experimental Study about the Effect of Urokinase Injected into the Ventricle on Intraventricular Hemorrhage

ABSTRACT

For the reduction of morbidity, such as an acute hydrocephalus, following intraventricular hemorrhage, we attempted to produce a lysis of the experimental intraventricular hemorrhage by a direct intraventricular injection of fibrinolytic agent. Urokinase was used as the fibrinolytic activator. Sixty-four adult rabbits were used in this study. The animals were divided into 5 groups to investigate the effect of urokinase in different time interval of urokinase injection. Intraventricular hemorrhage was made by an injection of 0.3cc of autogenous venous blood. Group I was the control group in which intraventricular injection of blood or urokinase was only done. In Group II and III urokinase was injected into the ventricule 30 minutes and 2 hours after the blood injection. In Group IV urokinase was injected into the ventricle at the same time of the blood injection. In Group V urokinase was injected into the ventricle at the same time of the blood injection, and then the urokinase injection was repeated 24 hours later. The animals of each group were sacrificed on the 1st, 2nd, 3rd and 7th day successively after the experimental procedures. The brains were examined to observe the outcome of intraventricular hematoma with urokinase injection and the consequent changes of the ventricular system grossly and microscopically. The results were as follows The duration of the remaining hematoma in the ventricles and basal cisterns was 7 days in both the control and the urokinase injection groups equally. In the group of repeated urokinase injection the duration of remaining hematoma in the ventricular system was shortened to 5 days after the blood injection. Upon the ventricular dilatation, the blood injection control group showed moderate dilatation persistently for 1 week ; from minimal to moderate dilatations were found in the urokinase injection groups. In the microscopic examination there were no definite abnormal changes on the ventricular walls and leptomeninges throughout 1 week in the urokinase injection control group. The group of repeated urokinase injection revealed mild flattening and denudation of the ependyma of the ventricular system than the group of single urokinase injection.