Grades subarachnoid haemorrhage CT appearance to estimate risk of delayed cerebral ischaemia.
Modified Fisher Scale: Clinical Guide
Browse Knowledge HubGrades subarachnoid haemorrhage CT appearance to estimate risk of delayed cerebral ischaemia.
Overview
Grades subarachnoid haemorrhage CT appearance to estimate risk of delayed cerebral ischaemia.
Clinical Significance
Higher grades generally indicate greater risk of symptomatic vasospasm, particularly grade 4.
When to Use
- Use as structured clinical decision support when the required data are available and reliable.
How It Is Calculated
- The displayed variables are combined using the published equation, decision rule or weighted point system.
Interpretation
- Higher grades generally indicate greater risk of symptomatic vasospasm, particularly grade 4.
Worked Example
Enter verified patient data in the displayed units; MedicalC applies the published model.
Limitations
- Risk and classification tools can be misapplied outside their validated population.
- Missing, estimated or non-contemporaneous data may materially change the result.
Clinical Pearls
- Document the input values, units, date and clinical setting with the result.
- Use serial scores only when the same instrument and measurement method are used consistently.
Common Mistakes
- Using the tool without confirming entry criteria.
- Using approximate or incorrectly converted laboratory values.
- Treating a prognostic score as a standalone treatment decision.
Frequently Asked Questions
What does this tool calculate?
Grades subarachnoid haemorrhage CT appearance to estimate risk of delayed cerebral ischaemia.
Can this result be used alone?
No. Interpret it with the full clinical assessment, applicable entry criteria and current guidance.
References
- Frontera JA et al. Neurosurgery. 2006;59:21-27. — Primary or supporting reference for the implemented model.
Reviewed by: MedicalC Clinical Editorial Team
Last reviewed: July 2026
Clinical Disclaimer
MedicalC calculators and clinical tools are intended to support healthcare professionals. They do not replace clinical judgement, individual patient assessment, local guidance or specialist advice.
Results should always be interpreted in the context of the patient’s history, examination, investigations, current clinical condition and applicable professional guidance.
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