Etminan et al conducted a Delphi consensus to consider factors influencing a decision to treat an unruptured intracranial aneurysm or not. The authors are from multiple institutions from around the world.
Patient selection: unruptured intracranial aneurysm
Factors that favor treating the aneurysm:
(1) age < 30 years
(2) familial intracranial aneurysms
(3) episode of subarachnoid hemorrhage from a different aneurysm
(4) aneurysm size > 13 mm
(5) sac lobulation
(6) location (anterior or posterior communicating artery; basilar artery bifurcation)
(7) growth of the aneurysm
(8) de novo formation of an aneurysm
(9) symptoms (cranial nerve deficits, mass effect)
(10) thromboembolic events
Patient factors for conservative management:
(1) chronic or malignant disease with life expectancy < 5 years
(2) presence of a neurocognitive disorder
(3) age > 80 years
Factors associated with reduction in rupture risk:
(1) blood pressure control
(2) nicotine cessation
Risk factors associated with treatment risk:
(1) aneurysm diameter > 20 mm
