Fisher scale


The Fisher scale is used to assess the amount of blood visible on a CT scan following subarachnoid hemorrhage. Higher Fisher grades are associated with a worse prognosis and increased mortality.

1

No hemorrhage is evident.

2

Subarachnoid hemorrhage less than 1mm thick.

3

Subarachnoid hemorrhage is more than 1mm thick.

4

Subarachnoid hemorrhage of any thickness with intraventricular hemorrhage (IVH) or parenchymal extension. 1).

Modified Fisher Grading Scale for Subarachnoid Hemorrhage

see Modified Fisher Grading Scale for Subarachnoid Hemorrhage

Elderly patients, and especially the subgroup with a Fisher Scale 3 bleeding pattern, had a high risk for an unfavorable outcome, whereas the subgroup of Non perimesencephalic subarachnoid hemorrhage NPM-SAH without a Fisher Grade 3 bleeding pattern had a favorable outcome, similar to perimesencephalic subarachnoid hemorrhage (PM)-SAH.

1)
Fisher C, Kistler J, Davis J (1980). “Relation of cerebral vasospasm to subarachnoid hemorrhage visualized by computerized tomographic scanning”. Neurosurgery 6 (1): 1–9.