Fatal Basilar Aneurysm Rupture 6 Months Following Pipeline Flow Diversion Treatment

The introduction of flow diverters represents a major paradigm shift in the endovascular treatment of intracranial aneurysms from deconstructive, endosaccular, aneurysm treatment to reconstructive, endoluminal, diseased parent vessel treatment. The theoretical concept of flow diversion (FD) technology relies on the ability offlowdiverters to induce a change in arterial and intra-aneurysmal hemodynamics leading to progressive thrombosis, occlusion, and subsequent healing of the aneurysm.1 However, the time course of the healing process to occur is unclear and is probably influenced by factors such as aneurysm size and morphology, the type of flow diverter used, the resultant flow change, the parent vessel geometry, and the patient’s blood coagulation profile.1,2 Thus, an aneurysm may remain unprotected and prone to rupture for an uncertain period after endovascular FD treatment. Delayed aneurysmal rupture post-FD treatment has been estimated to occur in 1% of all aneurysms treated and in 2% of aneurysms larger than 10 mm.1 Very delayed aneurysm