Chronological changes in brain edema induced by experimental intracerebral hematoma in cats.

To investigate the temporary profile of changing perifocal brain edema around an intracerebral hematoma (ICH), we developed an experimental ICH model using cats. The developing perifocal edema in the white matter around the hematoma was measured by means of a gravimetric technique. Edema was more severe near the ICH, and declined with increasing distance. Edema was mild 2 hours after the onset of the ICH, and was most severe in all the regions examined 3 days later. Edema decreased but still existed in all regions 7 days after the onset of the ICH. The results suggest that the mechanism of the development of edema associated with ICH seems to differ from that associated with a cold injury. This experimental ICH model proved to be useful for the study of formation, expansion, and resolution of edema associated with ICH.