Immediate and Follow-up Results for 44 Consecutive Cases of Small (<10 Mm) Internal Carotid Artery Aneurysms Treated with the Pipeline Embolization Device

Background: The pipeline embolization device (PED) provides effective, durable and safe endovascular reconstruction of large and giant intracranial aneurysms. However, 80% of all cerebral aneurysms found in the general population are less than 10 mm in size. Treatment of small aneurysms (<10 mm) with flow diverters may be advantageous over endosaccular modalities that carry risks of procedural rupture during aneurysm access or coil placement.

Methods: We retrospectively reviewed a prospective, single-center aneurysm database to identify all patients with small (<10 mm) internal carotid artery (ICA) aneurysms who underwent endovascular treatment using the PED. Patient demographics, aneurysm characteristics, procedural details, complications, and technical and clinical outcomes were analyzed.

Results: Forty-four cases were performed in 41 patients (age range 31-78 years). PED was successfully implanted in 42 cases. A single PED was used in 37/42 (88%) cases. Mean postprocedure hospital stay was 1.7 ± 0.3 days and 98% of patients were discharged home. Major complication occurred in one patient (2.3%), who died of early subarachnoid hemorrhage. Transient neurological deficit, delayed intracerebral hemorrhage (asymptomatic), and delayed groin infection occurred in one patient each. Follow-up rate was 91.8% (45 aneurysms in 35 patients) with a mean follow-up of 4.0 ± 1.9 months. By 6 months post-PED implantation, angiographic success (complete or near complete aneurysm occlusion) was observed in 80%. Mild (<50%), asymptomatic, nonflow limiting in-stent stenosis was observed in 5.4% (2/37 cases). All the 35 patients with follow-up remained at preprocedure neurological baseline.

Conclusion: Small (<10 mm) ICA aneurysm treatment with PED implantation is safe and carries a high rate of early angiographic success.