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Modified Fisher Grading Scale for Subarachnoid Hemorrhage (SAH)

Calculators  Neurology
Modified Fisher Grading Scale is a quick and effective tool utilized to assess symptomatic vasospasm after subarachnoid hemorrhage.
Signs/ Symptoms
No SAH present 0
Focal or diffuse thin SAH 1
Focal or diffuse thick SAH 2
Intraventricular hemorrhage (IVH) present
No 0
Yes 10


Measured Factor
Symptomatic vasospasm
Measured Factor Disease
  • Symptomatic vasospasm
Measured Factor Detail
Modified Fisher Grading Scale is only applicable to aneurysmal subarachnoid hemorrhage (aSAH). It is used to determine symptomatic vasospasm after subarachnoid hemorrhage more accurately on computed tomographic scans. This scale excludes patients with thick cisternal blood and concomitant intraparenchymal or intraventricular blood.
Body System
Measured Factor Low Impact
  • Modified Fisher Grade 0 illustrates no subarachnoid hemorrhage and no intraventricular blood.
Measured Factor High Impact
  • Modified Fisher Grade 1 or >1 indicates presence of symptomatic vasospasm.

Result Interpretation

Ranges Ranges
  • Critical High: Modified Fisher Grade 1 or >1
  • Normal: Grade 0
Result High Conditions
  • Symptomatic vasospasm


Study Validation 1
This study is to determine the best scale which predicts symptomatic vasospasm after subarachnoid haemorrhage by comparing modification of the Fisher computed tomographic rating scale and original Fisher scale. Out of 1355 patients, 451 patients developed symptomatic vasospasm. For modified Fischer scale referenced to Grade 0 to 1 patients, crude odd ratios for vasospasm was 1.6 for Grade 2, 1.6 for Grade 3, and 2.2 for Grade 4. Original Fisher scale, compared with  Grade 1, the odd ratios for vasospasm was 1.3  for Grade 2, 2.2 for Grade 3, and 1.7 for Grade 4. Risk factors for symptomatic vasospasm were identified as early angiographic vasospasm, neurological grade, history of hypertension, elevated admission mean arterial pressure. The mFischer scale remained an appropriate predictor of vasospasm after adjusting for these variables whereas the original Fisher scale was not. It is concluded that the modified Fisher scale predicts symptomatic vasospasm after subarachnoid haemorrhage more accurately than the original Fisher scale.
References: 1
Study Validation 2
In this retrospective cohort, single-centre study comparison of the Fisher scale with two newer radiographic scales has been done for the prediction of poor outcome, vasospasm, and delayed infarction. It involves 271 patients with a ruptured cerebral aneurysm. The result showed that when the score was 3, the risk of complications was high with the Fisher scale, but not for other scores. In contrast, using the other scales, there was a more linear relationship between a rising score and the frequency of complications. In modified Fisher scale, each stepwise increase was associated with a delayed infarction, escalating risk of vasospasm, and poor prognosis. It is concluded that the clinical performance of modified Fischer and Claassen scales is superior to Fisher scale.
References: 2
Study Additional 1
The authors aim to validate and appraise the Practical Risk Chart externally. Results showed that a total of 125 patients with the Practical Risk Chart, aSAH (aneurysmal subarachnoid haemorrhage), adequately predicted DCI (AUC of 0.66). Amount of intracranial blood and Clinical grade on admission were the strongest predictors of clinical vasospasm and DCI. It is concluded that the Practical Risk Chart sufficiently predicts the risk of DCI following aSAH. However, a simpler stratification scheme is represented by the best-fit model, using the modified Fisher scale and the Hunt and Hess grade and, produces a comparable AUC.
References: 3
Study Additional 2
Comparison of the modified Graeb score (mGS) to the mFS has been made in this study for the risk prediction of DCI also to investigate the predictive accuracy if incorporation of an mGS cut-point into the mFS is done. Results have shown that both mGS and mFS had similar discrimination for DCI with AUC- 0.608 vs 0.618 at P = .79. A new scale (mFS and mGS) improved the AUC compared to the mFS having AUC: 0.647 vs 0.608 at P = .022). Therefore it is concluded that the mGS and mFS have similar prognostic utility. Considering for IVH volume mFS has shown improvement in the prediction of DCI.
References: 4
Study Additional 3
The study involves 1200 consecutive SAH patients enrolled in the Columbia University SAH Outcomes Project. To identify the predictors of in-hospital mortality analysis was performed. Admission predictors of mortality were admission Glasgow Coma Scale score, age, large aneurysm size, loss of consciousness at ictus, Chronic Health Evaluation II (APACHE II) physiologic subscore, Acute Physiology and, Modified Fisher Scale score. In multivariable analysis hospital complications which further increased the risk of dying included rebleeding,  hypernatremia, global cerebral edema, pulmonary edema, hepatic failure, myocardial ischemia. Delayed cerebral ischemia, from vasospam did not predict the mortality. It has been concluded that strategies arising in minimising the aneurysm rebleeding and early brain injury ensure to further reduce the mortality after SAH.
References: 5


  1. Frontera JA, Claassen J, Schmidt JM, Wartenberg KE, Temes R, Connolly ES Jr, et al. Prediction of symptomatic vasospasm after subarachnoid hemorrhage: the modified fisher scale. Neurosurgery. 2006;59(1):21-7.
  2. Kramer AH, Hehir M, Nathan B, Gress D, Dumont AS, Kassell NF, et al. A comparison of 3 radiographic scales for the prediction of delayed ischemia and prognosis following subarachnoid hemorrhage. J Neurosurg. 2008;109(2):199-207.
  3. Foreman PM, Chua MH, Harrigan MR, Fisher WS 3rd, Tubbs RS, Shoja MM, et al. External validation of the Practical Risk Chart for the prediction of delayed cerebral ischemia following aneurysmal subarachnoid hemorrhage. J Neurosurg. 2017;126(5):1530-1536.
  4. Eagles ME, Jaja BNR, Macdonald RL. Incorporating a Modified Graeb Score to the Modified Fisher Scale for Improved Risk Prediction of Delayed Cerebral Ischemia Following Aneurysmal Subarachnoid Hemorrhage. Neurosurgery. 2018;82(3):299-305.
  5. Lantigua H, Ortega-gutierrez S, Schmidt JM, Lee K, Badjatia N, Agarwal S, et al. Subarachnoid hemorrhage: who dies, and why?. Crit Care. 2015;19:309.