Pipeline embolization device treatment of internal carotid artery terminus aneurysms

Background: The pipeline embolization device (PED) is approved for the treatment of large aneurysms of the proximal internal carotid artery (ICA). Its off-label application in treating aneurysms located specifically at the ICA terminus (ICA-T) has not been studied.

Methods: We conducted a retrospective chart review of patients from 2011 to 7 treated with PEDs. Out of 365 patients, 10 patients with ICA-T aneurysms were included. Patient demographics, procedural information, follow-up imaging, and clinical assessments were recorded.

Results: Mean age was 46.9 years (± 8.8), and 6 (60%) patients were women. The mean maximum diameter of the aneurysms treated was 14.7 mm (± 10.7) and the mean neck diameter was 9.3 mm (± 6.6). Reasons for presentation included six incidental findings, one acute subarachnoid hemorrhage (SAH), and three patients with prior SAH. Kamran-Byrne Occlusion Scale scores for the treated aneurysms were as follows: three class IV (complete obliteration), four class III (<50% filling in both height and width for fusiform aneurysms or residual neck for saccular aneurysms), one class II fusiform aneurysm, 1 class 0 saccular aneurysm (residual aneurysm body), and one not classified due to pipeline thrombosis. Two clinically asymptomatic complications were noted: one patient who had a small distal cortical SAH post PED and one patient whose stent was found to be thrombosed on follow-up angiogram. All patients were seen in follow-up, and no patients were found to have worsening of their pre-procedure modified Rankin Scale score.

Conclusion: The PED has potential for treating ICA-T aneurysms not amenable to conventional treatment strategies. Further studies are warranted to confirm the long term outcomes.