Subarachnoid hemorrhage - Fisher CT grading scale of subarachnoid bleeding

Fisher CT grading scale is used to grade severity of intracranial subarachnoid hemorrhage associated with rupture of an intracranial aneurysm. This scale predicts the risk of subsequent arterial spasms.

Group Description
Group I no hemorrhage
Group II subarachnoid hemorrhage <1mm thick
Group III subarachnoid hemorrhage >=1mm thick
Group IV intracerebral or intraventricular hemorrhage with diffuse or no subarachnoid hemorrhage of any thickness


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