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Prospective study on embolization of intracranial aneurysms with the pipeline device: the PREMIER study 1 year
Ricardo A Hanel1, David F Kallmes2, Demetrius Klee Lopes3
1Baptist Neurological Institute, Lyerly Neurosurgery, Jacksonville, Florida, USA.
Background:
Preliminary clinical studies on the safety and efficacy of the pipeline embolization device (PED) for the treatment of small/medium aneurysms have demonstrated high occlusion rates with low complications.
Objective:
To evaluate the safety and effectiveness of the PED for treatment of wide necked small and medium intracranial aneurysms.
Methods:
PREMIER is a prospective, multicenter, single arm trial. Patients were treated with the PED for unruptured wide necked aneurysms, measuring ≤12 mm along the internal carotid artery or vertebral artery, between July 2014 and November 2015. At 1 year post-procedure, the primary effectiveness endpoint was complete occlusion (Raymond grade 1) without major parent vessel stenosis (≤50%) or retreatment, and the primary safety endpoint was major stroke in the territory supplied by the treated artery or neurologic death.
Results:
A total of 141 patients were treated with PEDs (mean age 54.6±11.3 years, 87.9% (124/141) women). Mean aneurysm size was 5.0±1.92 mm, and 84.4% (119/141) measured <7 mm. PED placement was successful in 99.3% (140/141) of patients. Mean number of PEDs implanted per patient was 1.1±0.26; a single PED was used in 92.9% (131/141) of patients. At 1 year, 97.9% (138/141) of patients underwent follow-up angiography with 76.8% (106/138) of patients having met the study's primary effectiveness endpoint. The combined major morbidity and mortality rate was 2.1% (3/140).
Conclusions:
Treatment of wide necked small/medium aneurysms with the PED results in high rates of complete occlusion without significant parent vessel stenosis and low rates of permanent neurologic complications.
Trial Registration:
NCT02186561.
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