Abstract
The former classification of SAH was based on neurological grading system. Since the incidence of symptomatic vasospasm was well correlated to hematoma in the basal cistern as seen on CT it has been necessary to formulate a new CT grading of SAH. 166 cases of SAH, admitted from January 1982 to December 1984 out of a total of 239 SAH cases admitted to Fujita-Gakuen Univ. Hospital, became the object of this study. CT was taken within 48 hours after the onset and rebleeding did not occur in these cases.
CT grading system was decided as follows grade 1: a little hematoma in the basal cistern grade 2: much hematoma in the basal cistern grade 3: packed hematoma in the basal cistern grade 4: intracerebral or intraventricular hematoma with or without CT grade 1
grade 5: intracerebral or intraventricular hematoma with CT grade 2 or 3
Subgrade was formulated in grade 4 and 5 depending on the size of hematoma and midline shift on CT, namely (a) and (b). 4a or 5a means small hematoma without midline shift, 4b or 5b means large hematoma with midline shift. This grading system was well correlated to the patient's outcome. The difference of outcome between grade 1 and 2, 2 and 3, 3 and 5, 4 and 5, was statistically significant.
