Summary
Patients with headaches who display certain red flags should undergo neuroimaging to rule out serious pathology. Key red flags include:
- Sudden onset (thunderclap): A headache that reaches peak intensity within seconds to minutes may indicate subarachnoid hemorrhage or vascular emergencies 1.
- New-onset headache in older patients: New headaches, especially in patients older than 50, can be a harbinger of temporal arteritis, intracranial neoplasm, or other pathologies 12.
- Focal neurological deficits: Any focal weakness, sensory changes, or other localized deficits should prompt imaging to evaluate for stroke, mass lesion, or demyelinating disease 2.
- Altered mental status or impaired consciousness: This may indicate increased intracranial pressure, hemorrhage, or infection 1.
- Signs of increased intracranial pressure: The presence of papilledema or new-onset seizure raises concerns for intracranial mass, hydrocephalus, or hemorrhage 2.
- Systemic symptoms or immunocompromise: Fever, weight loss, or immunosuppression can raise suspicion for meningitis, brain abscess, or other infections 1.
- Headache with a history of trauma: Recent head trauma with a headache may suggest intracranial hemorrhage, particularly in higher risk patients (e.g., on anticoagulation) 2.
At a Glance
| Red Flag Feature | Potential Concern | Action |
|---|
| Sudden onset, severe ("thunderclap") headache | Subarachnoid hemorrhage, vascular event | Immediate imaging (CT/MRI) |
| New-onset headache in patients >50 | Temporal arteritis, neoplasm, cerebrovascular etiology | Advanced imaging |
| Focal neurological deficits | Stroke, mass lesion, demyelinating disease | Urgent neuroimaging |
| Altered mental status/impairment | Increased intracranial pressure, hemorrhage/infection | Emergent imaging |
| Signs of increased intracranial pressure (papilledema) | Brain mass, hydrocephalus, hemorrhage | Neuroimaging evaluation |
| Systemic symptoms (fever/weight loss) or immunosuppression | Meningitis, abscess | Consider contrast imaging |
| Recent head trauma | Intracranial hemorrhage | CT head evaluation |
Recognizing these red flags in the context of headache is crucial, as timely imaging—often with non-contrast head CT or MRI—can be life-saving and guide further management 12.