Resolution of cranial neuropathies following treatment of intracranial aneurysms with the Pipeline Embolization Device

Object: Intracranial aneurysms, especially those of the cavernous segment of the internal carotid artery (ICA), can present with cranial nerve (CN) palsies. The Pipeline Embolization Device (PED) has demonstrated safety and efficacy in the treatment of cerebral aneurysms by flow diversion, but little data exist reporting the outcomes of cranial neuropathies following treatment with the device.

Methods: The prospectively maintained Barrow Neurological Institute's endovascular database was reviewed for all patients treated with the PED after presenting with one or more CN palsies secondary to a cerebral aneurysm since May 2011. Patient charts and digital subtraction angiograms were reviewed to report clinical and angiographic outcomes. Only patients with clinical follow-up were included in the analysis.

Results: A total of 127 patients were treated with the PED at the authors' institution after FDA approval. Twentytwo patients presented with cranial neuropathies, for initial inclusion in this study. Of these, 20 had sufficient followup for analysis. Cranial neuropathies included those of CN II, III, V, and VI, with presenting symptoms of diplopia, decreased visual acuity, and facial numbness and/or pain. Thirteen lesions were cavernous segment ICA aneurysms, whereas the remainder included supraclinoid and petrous segment ICA, posterior communicating artery, and basilar trunk aneurysms. At an average clinical follow-up of 9.55 months, 15 patients (75%) had resolution or significant improvement of their cranial neuropathies, and the remaining 5 had stable symptoms. Of the 18 patients with angiographic follow-up, 12 (66.7%) demonstrated complete obliteration or small neck residual, whereas 6 (33.3%) had residual lesion. Patients with complete or near-complete obliteration of their lesion were significantly more likely to demonstrate symptomatic improvement at follow-up (p = 0.009). Two patients with persistent symptoms were eventually treated with microsurgical bypass. Transient complications in this series included 6 (30%) extracranial hemorrhagic complications related to dual-antiplatelet therapy, all of which were managed medically. There was 1 delayed right ICA occlusion following retreatment that led to microsurgical bypass.

Conclusions: Intracranial aneurysms presenting with one or more CN palsies show a high rate of clinical improvement after treatment with the PED. Clinical outcomes must be weighed against the risks and challenges faced with flow diverters. Further research is warranted for patients whose symptoms do not respond optimally to device placement.