Endovascular Treatment of Anterior Circulation Aneurysms With the p64 Flow Modulation Device: Mid- and Long-Term Results in 617 Aneurysms From a Single Center

Abstract

Background: Flow diverters have become an important tool in the treatment of intracranial aneurysms, especially when dealing with difficult-to-treat or complex aneurysms. The p64 is the only fully resheathable and mechanically detachable flow diverter available for clinical use.

Objective: To evaluate the safety and effectiveness of p64 for the treatment of intracranial saccular unruptured aneurysms arising from the anterior circulation over a long-term follow-up period.

Methods: We retrospectively reviewed our prospectively maintained database to identify all patients who underwent treatment for an intracranial saccular (unruptured or beyond the acute hemorrhage phase) aneurysm arising from the anterior circulation with ≥1 p64 between December 2011 and December 2019. Fusiform aneurysms and dissections were excluded. Aneurysms with prior or concomitant saccular treatment (eg, coiling and clipping) were included. Aneurysms with parent vessel implants other than p64 were excluded. Anatomic features, intraprocedural complications, clinical outcome, as well as clinical and angiographic follow-ups were all recorded.

Results: In total, 530 patients (388 females; median age 55.9 yr) with 617 intracranial aneurysms met the inclusion criteria. The average number of devices used per aneurysm was 1.1 (range 1-3). Mean aneurysm dome size was 4.8 mm (range 1-27 mm). Treatment-related morbimortality was 2.4%. Early, mid-term, and long-term angiographic follow-up showed complete or near-complete aneurysm occlusion in 76.8%, 89.7%, and 94.5%, respectively.

Conclusion: Treatment of intracranial saccular unruptured aneurysms of the anterior circulation using p64 is a safe and effective treatment option with high rate of occlusion at long-term follow-up and low morbimortality.

Keywords: Anterior circulation aneurysm; Endovascular treatment; Flow diversion; Flow diverter stent; Intracranial aneurysms; p64 Flow Modulation Device.

© Congress of Neurological Surgeons 2021.

Figures

Graphical Abstract

FIGURE 1.

Flow chart representing the included aneurysms.

FIGURE 2.

Unruptured right paraophthalmic aneurysm in a 65 yr-old female treated initially with a single Medina device and a single p64 FDS, both deployed during the same procedure A and B. Three days after treatment, the patient presented headache. Subsequent magnetic resonance imaging (MRI) showed bilateral cortical subarachnoidal hemorrhage C due to hyper-response to the DAPT (ASA and ticagrelor), which was confirmed by Multiplate (ADP 7 U, ASPI 6 U) and VerifyNow (P2Y12 45, ARU 369). The afternoon dose of ticagrelor was skipped. The following morning, the patient presented acute onset of left hemiparesis. Both Multiplate and VerifyNow showed then an insufficient inhibition for ticagrelor. Subsequent digital subtraction angiography (DSA) confirmed occlusion of the right ICA due to acute thrombosis of the previous implanted FDS D, which was successfully recanalized by mechanical thrombectomy and aspiration E. The patient returned to baseline neurology (mRS 0). Angiography performed 3 mo after treatment demonstrated complete exclusion of the aneurysm from the circulation F.

FIGURE 3.

Unruptured M1 aneurysm in a 46 yr-old female treated with a single coil and a single p64 FDS A and B. The 3-mo follow-up angiography C showed a near occlusion of the aneurysms with a small neck remnant. The small lenticulostriate artery covered by the FDS was still patent. The 9-mo follow-up D showed complete occlusion of the aneurysm. The covered branch was reduced in filling but still patent. At 34-mo angiographic follow-up E showed partial recanalization of the aneurysm sac. The first follow-up angiography after retreatment with a second p64 device F showed again complete occlusion of the aneurysm.