Non-invasive brain-imaging tools have improved constantly over the last two decades, but their increased accessibility leaves doctors with a growing number of patients diagnosed with intracranial vascular disease at a stage before clinical symptoms or actual stroke have occurred. Unruptured aneurysms, non-haemorrhagic brain arteriovenous malformations, silent cavernomas and asymptomatic arterial stenoses—to name but a few—constitute vexing management problems in current clinical practice, as treatment decisions have to take into account the risk of invasive versus non-invasive strategies.^1,2

On the basis of a careful review of selected literature sources and experiences at their own treatment centre, Pouratian et al³ provide a useful overview on factors influencing current invasive treatment strategies for patients diagnosed with an unruptured intracranial aneurysm. Their review leaves little doubt that the matter cannot be easily solved, and that there …