Long-term outcomes following pipeline embolization of unruptured aneurysms

Flow diversion using the pipeline embolization device (PED) for unruptured aneurysms is associated with high occlusion and low morbidity and mortality. However, most reports have limited follow-up of 1-2 years. Therefore, we sought to report our outcomes after PED for unruptured aneurysms in patients with at least 5-years of follow-up.

Review of patients undergoing PED for unruptured aneurysms from 2009 to 2016.

Overall, 135 patients with 138 aneurysms were included for analysis. Seventy-eight percent of aneurysms (n=107) over a median radiographic follow-up of 5.0 years underwent complete occlusion. Among aneurysms with at least 5-years of radiographic follow-up (n=71), 79% (n=56) achieved complete obliteration. No aneurysm recanalized after radiographic obliteration. Furthermore, over a median clinical follow-up period of 4.9 years, 84% of patients (n=115) self-reported mRS scores between 0 and 2. For patients with at least 5-years of clinical follow-up, 88% (n=61) reported mRS between 0 and 2. In total, 3% (n=4) of patients experienced a major, non-fatal neurologic complication related to the PED, 5% (n=7) of patients experienced a minor neurologic complication related to PED placement, and 2% (n=3) died from either delayed aneurysm rupture, delayed ipsilateral hemorrhage after PED placement, or delayed (9 months after treatment) neural compression after progressive thrombosis of a PED-treated dolichoectactic vertebrobasilar aneurysm.

Treatment of unruptured aneurysms with the PED is associated with high rates of long-term angiographic occlusion and low, albeit clinically important, rates of major neurologic morbidity and mortality. Thus, flow diversion via PED placement is safe, effective, and durable.