A2, M2, P2 aneurysms and beyond: results of treatment with pipeline embolization device in 65 patients

Abstract

BackgroundIntracranial aneurysms located in the distal vessels are rare and remain a challenge to treat through surgical or endovascular interventions.ObjectiveTo describe a multicenter approach with flow diversion using the pipeline embolization device (PED) for treatment of distal intracranial aneurysms.MethodsCases of distal intracranial aneurysms defined as starting on or beyond the A2 anterior cerebral artery, M2 middle cerebral artery, and P2 posterior cerebral artery segments were included in the final analysis.Results65 patients with distal aneurysms treated with the PED were analyzed. Median aneurysm size at the largest diameter was 7.0 mm, 60% were of a saccular morphology, and 9/65 (13.8%) patients presented in the setting of acute rupture. Angiographic follow-up data were available for 53 patients, with a median follow-up time of 6 months: 44/53 (83%) aneurysms showed complete obliteration, 7/53 (13.2%) showed reduced filling, and 2/53 (3%) showed persistent filling. There was no association between patient characteristics, including aneurysm size (P=0.36), parent vessel diameter (P=0.27), location (P=0.81), morphology (P=0.63), ruptured status on admission (P=0.57), or evidence of angiographic occlusion at the end of the embolization procedure (P=0.49). Clinical outcome data were available for 60/65 patients: 95% (57/60) had good clinical outcome (modified Rankin Scale score of 0–2) at 3 months.ConclusionsThis large multicenter study of patients with A2, M2, and P2 distal aneurysms treated with the PED showed that flow diversion may be an effective treatment approach for this rare type of vascular pathology. The procedural compilation rate of 7.7% indicates the need for further studies as the flow diversion technology constantly evolves.

Expanding Indications for Flow Diverters: Distal Aneurysms, Bifurcation Aneurysms, Small Aneurysms, Previously Coiled Aneurysms and Clipped Aneurysms, and Carotid Cavernous Fistulas

“…8,16-19 Perforators are usually kept patent by a “sump” effect; however, acute or late symptomatic or asymptomatic perforator stroke is reported. 6,17-19 In the Saleme et al 18 series, permanent neurological deficits occurred in 9.4% of patients during hospitalization and transient events occurred in 17.4% of cases in the 6-mo period. Careful dual antiplatelet therapy and use of a single slightly oversized FDD, to reduce metal coverage, might be useful to decrease the risk of perforators occlusion.…”

“…The occlusion rate was 83% (mean follow-up time: 6 mo). 6 In two series of distal vessel aneurysms treated with the FRED Jr or the PED complete/near complete, occlusion rate was 78%. The rate of ischemic events varied from 7% to 17.4%.…”

The p48 MW flow modulation device for treatment of unruptured, saccular intracranial aneurysms: a single center experience from 77 consecutive aneurysms

“…A multicohort study from 3 centers involving 46 patients and 46 distal aneurysms, the use of the PED or FRED resulted in nearly 80% rate of complete or near-complete occlusion after a mean follow-up of 13 months with a complications rate of 4.3% resulting form 2 cases of perforator ischemia (Ravindran et al, 2018 ). A recent multicenter analysis of a relatively large cohort of distal aneurysms involving the second segments of the anterior, middle and posterior cerebral arteries demonstrated a high efficacy rate of flow diversion in these distal and challenging configuration (Primiani et al, 2019 ). The authors reported a procedural complication rate of 7.7% and 95% rate of good clinical outcome among 60 patients with available clinical follow-ups.…”

Morphological parameters of middle cerebral arteries associated with aneurysm formation

“…MCA proximal and distal aneurysms are relatively rare, and most previous studies of proximal and distal aneurysms focus on the selection of treatment options for aneurysm rupture. Few studies exist on the relationship between MCA geometry and the formation of proximal and distal aneurysms [24][25][26][27]. To the best of our knowledge, the relation of both the α and β to the formation of proximal and distal MCA aneurysms has not yet been reported.…”