Objectives: The pipeline embolization device (PED) is a treatment option for wide-neck intracranial aneurysms. The individual number of implants needed to securely exclude an aneurysm is unknown. Our primary objective was to compare midterm occlusion and complication rates in aneurysms treated with a single versus multiple PEDs without adjunctive coiling in a single procedure.
Patients and methods: Fifty-five patients harboring 58 intracranial aneurysms were treated with 121 PEDs between March 2011 and December 2013. About 38 aneurysms in 37 patients were treated exclusively with PED without adjunctive coiling in a single procedure. All pretreated (recurrent) aneurysms were excluded from analysis. Occlusion results were rated using the OKM-scale. Periprocedural complications were recorded.
Results: Immediate angiographic results showed favorable obliteration (OKM C1-3+D) in 5/20 (25%) single-PED cases versus 8/18 (44%) in multiple-PED cases (p=0.3); complete obliteration (OKM D) was achieved in 4/20 (20%) with single-PED versus 5/18 (28%) in the multiple-PED group (p=0.2). Midterm (median: 7 months) angiographic rates of favorable occlusion were significantly higher in the multiple-PED group: 14/20 (70%) in single-PED cases versus 15/15 (100%) in multiple-PED cases (p=0.03); complete occlusions were observed in 12/20 (60%) single-PED cases versus 14/15 (93%) in multiple-PED cases (p=0.05). Retreatment was necessary in 3/20 single-PED (15%) and in none of the multiple-PED cases. Procedural complications did not differ between groups.
Conclusion: The nonstaged use of multiple PEDs may result in a higher rate of favorable occlusions at midterm in wide-neck aneurysms treated without adjunctive coiling without significantly increasing the rate of procedural complications.
Keywords: aneurysm; endovascular; flow diversion; pipeline.