1984 Volume 24 Issue 8 Pages 607-614
Forty-nine cases of chronic subdural hematoma experienced during the past 5 years were analyzed as to the number of days elapsed following head injury, symptoms, and computerized tomography (CT) findings. As a result, the clinical course of chronic subdural hematoma was devided into the following 5 stages on the basis of the presumed pathologic processes.
The initial stage corresponded to a period of about 2 weeks after the precipitating injury; symptoms were absent; plain CT showed low-density areas (LDA) ; and metrizamide CT revealed metrizamide penetration into the LDA. The premature stage corresponded to a period of 2-4 weeks after trauma; no symptoms were present; plain CT showed LDA; and metrizamide CT revealed that metrizamide penetrated into the LDA with difficulty. The mature stage corresponded to a period of 30-60 days after trauma; CT showed iso-density areas (IDA) or high-density areas (HDA) with occasional enhancement effect; metrizamide penetration was not detected; and symptoms such as headache may have been present. The progressive stage typified chronic subdural hematoma; headache and focal symptoms were present; plain CT showed relative LDA, IDA, HDA or mixed-density areas (MDA) ; and enhancement of the contents of hematoma was observed in roughly half of the cases. The resolving stage was the stage in which hematoma had disappeared; plain CT showed relative LDA or LDA without mass sign; and metrizamide penetration was not detected. This clinical staging was useful in evaluating the pathologic picture of the chronic subdural hematoma and in determining suitable treatment.