Brain Aneurysm: Rupture Risk, Symptoms & Life-Saving Treatment

A brain (cerebral) aneurysm is a focal arterial dilation. Rupture causes subarachnoid hemorrhage (SAH)—a neurological emergency with ~40% mortality.

Rupture Warning Signs

• Thunderclap headache – "Worst headache of life," instantaneous peak.
• Nausea/vomiting, photophobia, neck stiffness
• Focal deficits: cranial nerve palsies (III, IV, VI), hemiparesis
• Seizures, decreased consciousness, coma

Unruptured Aneurysm Symptoms

• Often asymptomatic
• Mass effect: cranial nerve palsy (III → ptosis, dilated pupil), visual field defects
• Headaches (non-specific)

Treatment

• Surgical clipping – Craniotomy; permanent occlusion. Gold standard for accessible aneurysms.
• Endovascular coiling – Catheter-delivered platinum coils; less invasive. Flow diverters (Pipeline) for wide-neck/complex.
• Conservative – Small, asymptomatic, low-risk: serial imaging, BP control, smoking cessation.

Risk Factors for Rupture

• Size >7 mm (especially >10 mm)
• Location (posterior circulation, AComm)
• Growth on serial imaging
• Hypertension, smoking, family history, connective tissue disorders

Sudden thunderclap headache = call 911. Time is brain.