What are the symptoms and treatment for a suspected cerebral aneurysm?

Cerebral Aneurysm Symptoms and Treatment

Subarachnoid hemorrhage (SAH) from a ruptured cerebral aneurysm presents as "the worst headache of my life" and requires immediate evaluation with CT scan followed by lumbar puncture if CT is negative to prevent catastrophic rebleeding. 1

Clinical Presentation

Ruptured Aneurysm Symptoms

• Sudden, severe headache ("worst headache of my life") - reported by 80% of patients 1
• Nausea and/or vomiting (77% of cases)
• Loss of consciousness (53% of cases)
• Nuchal rigidity/neck stiffness (35% of cases)
• Focal neurological deficits (including cranial nerve palsies)
• Altered mental status

Warning Signs (Sentinel Leak)

• Milder headache 2-8 weeks before major rupture (20% of patients report warning headaches) 1
• May last several days
• Often misdiagnosed as migraine or tension headache
• Represents a critical opportunity for intervention before catastrophic rupture

Unruptured Aneurysm Symptoms

• Often asymptomatic
• May present with:
  • Cranial nerve palsies (particularly oculomotor nerve palsy with posterior circulation aneurysms)
  • Compression symptoms from large aneurysms
  • Vague headaches or dizziness

Diagnostic Algorithm

1. Initial Evaluation:

   • Non-contrast head CT scan (Class I, Level B) 1
   • If CT is negative but clinical suspicion remains high, perform lumbar puncture (Class I, Level B) 1
   • Xanthochromia evaluation is more sensitive after 12 hours from headache onset 1

2. Vascular Imaging:

   • Digital subtraction angiography (DSA) with 3D rotational angiography is the gold standard (Class I, Level B) 1
   • CT angiography (CTA) may be initially preferable but DSA remains definitive when CTA is negative 1
   • MR angiography (MRA) may be considered when conventional angiography cannot be performed promptly (Class IIb, Level B) 1

3. Clinical Grading:

   • Assess severity using validated scales (Class I, Level B) 1
   • Recommended scales: World Federation of Neurological Surgeons (WFNS), Hunt and Hess, Glasgow Coma Scale, Fisher Scale 1

Treatment Protocol

For Ruptured Aneurysms

1. Initial Management:

   • Secure airway, breathing, and circulation
   • Transfer to a high-volume center (>35 SAH cases/year) (Class I, Level B) 1
   • Control blood pressure with titratable agents to balance risk of rebleeding vs. cerebral perfusion (Class I, Level B) 1

2. Aneurysm Securing:

   • Urgent treatment within 24-48 hours to prevent rebleeding (Class I, Level B) 1
   • Endovascular coiling is preferred over surgical clipping for most aneurysms (Class I, Level A) 1
   • Complete obliteration of the aneurysm is recommended (Class I, Level B) 1

3. Medical Management:

   • Nimodipine administration for 14-21 days to improve neurological outcomes (Class I, Level A) 1, 2
   • Maintain euvolemia to prevent delayed cerebral ischemia (DCI) (Class I, Level B) 1
   • Treat symptomatic hydrocephalus with cerebrospinal fluid diversion (Class I, Level B) 1
   • Monitor for vasospasm (peaks 4-10 days after hemorrhage)

4. Vasospasm Management:

   • Maintain euvolemia rather than hypervolemia (Class I, Level B) 1
   • For symptomatic vasospasm, induced hypertension is recommended (Class IIa, Level B) 1
   • Consider endovascular treatment for refractory vasospasm (Class IIb, Level C) 1

For Unruptured Aneurysms

Treatment decisions should consider:

• Aneurysm size, location, and morphology
• Patient age and medical comorbidities
• Family history of aneurysmal SAH
• Growth on serial imaging

Treatment recommendations:

• Small (<10mm) asymptomatic aneurysms without prior SAH: observation may be reasonable, especially in older patients (>65 years) 1
• Symptomatic aneurysms of any size: consider treatment 1
• Aneurysms ≥10mm: strong consideration for treatment 1
• Basilar apex aneurysms: higher risk of rupture, lower threshold for treatment 1

Common Pitfalls and Caveats

1. Misdiagnosis: SAH is misdiagnosed in up to 12% of cases, often mistaken for migraine or tension headache 1

   • Always obtain CT scan for sudden severe headache
   • Perform LP if CT is negative but clinical suspicion remains high

2. Delayed Cerebral Ischemia: Particularly difficult to diagnose in comatose or sedated patients (WFNS grade 4-5) 3

   • Occurs in approximately 30% of patients, typically between days 4-10 after SAH
   • Higher incidence in high-grade SAH patients

3. Sentinel Headaches: Recognition of warning leaks is critical

   • 20% of patients report headaches days to weeks before major rupture 1
   • Represents a critical opportunity for intervention

4. Follow-up Imaging: Essential after treatment

   • Immediate post-treatment imaging to identify remnants (Class I, Level B) 1
   • Long-term follow-up to detect recurrence or de novo aneurysm formation 1

5. Cognitive Assessment: After treatment, comprehensive evaluation including cognitive assessment is reasonable (Class IIa, Level B) 1

By following this structured approach to diagnosis and management, the morbidity and mortality associated with cerebral aneurysms can be significantly reduced.