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Neurology Emergency Medicine Strong — sensitivity ~100% for neurosurgical lesions; validated in multiple centres

Canadian CT Head Rule

Identifies adults with minor head injury (GCS 13–15) who require CT head to detect clinically important brain injury or skull fracture. Applicable to patients with witnessed LOC, amnesia, or confusion.

Used in: Head Injury

Score interpretation

CT Not Required 0

No high or medium risk factors. Clinically important brain injury very unlikely.

→ CT head not indicated. Discharge with head injury advice. Return if: persistent headache, vomiting, drowsiness, focal neurology, seizure, confusion.

CT Indicated — Medium Risk (Possible Fracture / Haematoma) 1–9

Medium risk factors present. CT head recommended to exclude haematoma or skull fracture.

→ CT head. If normal: discharge with head injury advice. If abnormal: neurosurgery referral.

CT Indicated — High Risk (Neurosurgical Intervention Likely) ≥ 10

High risk factors present. Significant risk of injury requiring neurosurgical intervention.

→ Urgent CT head. Neurosurgery review. Airway assessment. Serial GCS. If deteriorating: anaesthetics / ITU.

Interpretation bands for the Canadian CT Head. Apply clinical judgement and local guidance.

References

Related

Curated clinical cross-links plus same-class fallbacks.

Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.