Pipeline Embolization Device for Treatment of Intracranial Aneurysms —The More, the Better? A Single-center Retrospective Observational Study

Abstract

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.