Long-term follow-up after treatment of intracranial aneurysms with the Pipeline embolization device: results from a single center

Abstract

Background and purpose: Stent-like, self-expandable devices, the so-called flow diverters, are increasingly used for the treatment of wide-neck cerebral aneurysms. The immediate and short-term results are promising, but no long-term results are available. The purpose of our research was to report the long-term angiographic and cross-sectional imaging results after placement of a PED in 12 patients with wide-neck intracranial aneurysms.

Materials and methods: Twelve wide-neck or otherwise untreatable cerebral aneurysms in 12 patients were treated with the PED. Angiography was performed at 6 and 24 months after treatment. Additional MR and CT angiograms were acquired.

Results: In all patients, angiographic or cross-sectional imaging follow-up of at least 27 months demonstrated complete occlusion of the aneurysms treated with the PED. There were no cases of aneurysm recurrence. Angiography at around 6 months showed complete occlusion in all cases, except 1 that showed complete occlusion at the 29-month follow-up. In 1 patient, a clinically asymptomatic 75% in-stent stenosis was seen on the angiography at 6 months but was resolved completely by balloon dilation. Device placement was successful in all patients. Distal embolization had occurred in 1 patient, but the clot was resolved completely without clinical sequelae. Almost immediate angiographic occlusion was achieved in 2 aneurysms and flow reduction in 10 aneurysms.

Conclusions: Treatment of wide-neck intracranial aneurysms by PED placement led to successful and durable occlusion in all cases, without severe complications. Endovascular treatment for in-stent stenosis should be considered cautiously, because the underlying stenosis may be transient and disappear within 12 months after treatment.

Fig 1.

A 76-year-old woman (patient 2) presents with a lobulated 4.1-mm recurrence of a previously coiled 8-mm ICA aneurysm (arrow, A). After placement of a single PED, the recurrence remains visible (arrow, B). At the 6-month angiographic follow-up, recurrence of the aneurysm neck is smaller, but still visible (arrow, C). MRA performed 13 months after PED placement demonstrates complete occlusion of the aneurysm (arrows, D–E) and patency of the parent artery (arrowhead, E). Angiography at 30 months confirms the results of the MR angiography, demonstrating complete occlusion of the aneurysm and excellent reconstruction of the parent artery (F).

Fig 2.

A 61-year-old woman (patient 9) presents with a 16 × 13 mm recurrence of a previously ruptured and subsequently coiled 22-mm ICA aneurysm at the origin of the posterior communicating artery (arrow, A). After placement of a single PED, flow reduction in the superior compartment of the aneurysm recurrence is demonstrated (arrow, B). Due to the broad base of the recurrence, a second PED is placed in a telescopic fashion to sufficiently cover the aneurysm neck and the adjacent arterial segments. After placement of the second PED, significant flow reduction is demonstrated (arrow, C). At the 6-month angiographic follow-up, complete occlusion of the aneurysm recurrence is visible (arrow, D). At the 30-month angiographic follow-up, the aneurysm recurrence is still completely occluded, with excellent reconstruction of the parent artery (arrows E and F).

Fig 3.

A 51-year-old woman (patient 11) harboring an incidental 10-mm paraophthalmic aneurysm (arrow, A). Immediately after treatment with a single PED, only minimal residual flow is visible on angiography (arrow, B). Angiography also depicts a minimal pre-existing lumen narrowing shortly before the funnel-shaped origin of the posterior communicating artery (arrowhead, A–B). At 6-month follow-up, angiography and 3D reconstruction of the rotational angiography show complete occlusion of the aneurysm and 75% stenosis at the distal end of the PED (arrows, C and D). At that time, the PED is fully deployed (E), but a small translucent rim along the inner surface of the PED is visible (arrows, F–G). Percutaneous balloon angioplasty is performed 7 months after PED placement. Control angiography after 13 months demonstrates only minimal residual stenosis (about 30% lumen narrowing; arrow, H) that is completely resolved, as demonstrated on the 31-month angiographic follow-up (arrows, I). However, a small translucent rim, possibly resembling a neointimal layer, is still visible on angiography (arrows, I). There are no signs of recurrence of the aneurysm, which remains completely occluded.