Introduction: Flow diverter has become the preferred treatment for large, fusiform or recurrent complex aneurysms. The purpose of this study is to demonstrate the safety and efficacy of Pipeline Embolisation Device in the treatment of small, unruptured internal carotid artery (ICA) aneurysms and compare it with conventional coil embolization( primary coiling/balloon assisted or stent assisted coiling)

Methods: IRB approval was obtained from the local Institutional board. From January 2010 to April 2013, 27 aneurysms with PED treatment and 72 aneurysms with conventional endovascular embolization were identified and included in the study. The information about patients, aneurysms, procedural complications and outcomes were carefully recorded. The efficacy and safety of treatments were analyzed and compared.

Results: The mean patient’s age was 60.0(SD:10.24) years in the PED group and 56.04(SD13.50) years in the coil/stent-coil group (p=0.200)(Table-1). Twenty-five aneurysms (92.6%) had angiographic follow-up after the PED treatment(mean:6.99 months). In the coil/stent-coil group, the angiographic follow-up was available for 58 aneurysms (80.6%) with a mean follow-up duration of 11.43 months.92% aneurysms treated by PED had complete occlusion at the last follow up whereas 70.7% occlusion rate was seen in the coil group (p=0.046)(Table 3 and 4). In the PED cohort, none of the patient had recanalization and only 1 patient was treated with additional PED in follow-up. Where as 17.2% recanalization (p=0.028) and 10.3% of retreatment(p=0.171)(Table 2) occurred in the coil group. Procedure-related complications (Table 3) did not differ between the PED and the coil group ( p=0.232). At the last follow-up 100% patient had a mRS of 0-1 in PED cohort and 95.5% in conventional endovascular group respectively.

Conclusions: The PED provided significantly higher complete occlusion rate than conventional-embolization, with no recanalization and significantly less retreatments with similar procedural risk. Our study has raised the pitch iun favor of PED for the treatment of small aneurysms as well.

Patient Care: Our research has shown that treatment of small aneurysms with PED carries lesser risk for re-canalization and re treatment when compared with other conventional endovascular measures.

Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the importance of use of PED for small aneurysms. 2) Discuss, in small groups about the recanalization, recurrence of aneurysm treated by PED 3) Identify an effective treatment for small cerebral aneurysms.

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