Review article
Flow-diverter devices in the treatment of intracranial aneurysms: A meta-analysis and systematic review
The Neuroradiology Journal 0(00) 1–6 ! The Author(s) 2016 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1971400915621321 neu.sagepub.com
Xianli Lv, Hongchao Yang, Peng Liu and Youxiang Li
Abstract Objective: The purpose of this report was to discuss the overall limitations, safety and efficacy of flow-diverter stenting for intracranial aneurysms. Methods: The authors performed a meta-analysis from January 2009 to September 2014 using the terms ‘‘flow diverter’’ and ‘‘intracranial aneurysms.’’ Additional studies were identified through references in each reviewed article. Data extraction, performed independently by the authors, included demographic data, technical and clinical complications, morbidity and mortality, aneurismal occlusion rates related to flow-diverter devices. The analysis was performed using a fixed effect. Results: Twenty-nine studies with 1524 patients and three to 62 months of follow-up were identified for analysis. The overall technical failure and complication rate was 9.3% (95% CI 6%–12.6%). The rate of procedure-related complication was 14% (95% CI 10.2%–17.9%) and 6.6% (95% CI 4%–9.1%) for morbidity and mortality. Fusiform, dissecting and circumferential aneurysm (OR 3.10, 95% CI 0.93–10.37) were significant risk factors for technical failure and complication. Posterior circulation location (OR 4.03, 95% CI 2.45–6.61), peripheral location (OR 2.74, 95% CI 1.52–4.94) and fusiform, dissecting and circumferential aneurysm (OR 1.95, 95% CI 1.15–3.30) were statistically significant risk factors for procedure-related complications. Posterior circulation location (OR 4.39, 95% CI 2.44–7.90) and peripheral location (OR 3.64, 95% CI 1.74–7.62) were statistically significant risk factors for morbidity and mortality. Conclusions: Fusiform, dissecting and circumferential aneurysm, posterior circulation and peripheral locations have greater procedure-related complications.
Keywords Intracranial aneurysm, endovascular treatment, flow-diverter stenting
Introduction
Methods
Complex unruptured aneurysms such as fusiform, large and/or giant, or wide neck, as well as very small aneurysms or blood blister aneurysms that might be untreatable by conventional coiling and recurrences, can be considered amenable to flow-diverter devices.1 However, flow-diverter devices may cause bleeding or ischemic complications, which are a considerable source of neurological morbidity and mortality.2 With an accumulating number of studies of flowdiverter device treatment of intracranial aneurysms, our understanding of its role in endovascular treatment of intracranial aneurysms continues to evolve.2,3 Unfortunately, there is a remarkable degree of heterogeneity in previous studies regarding results and outcomes of flow-diverter devices in the treatment of intracranial aneurysms.3 We performed a metaanalytical review of the literature about their efficacy, safety, limitations and developments.
A PubMed, Embase and Web of Science search using the terms ‘‘flow diverter’’ and ‘‘intracranial aneurysms’’ was performed from January 2009 to September 2014. We incorporated English-language studies including more than five patients treated with flow-diverter devices and follow-up outcome. References in the reviewed studies were also incorporated if the inclusion criteria were met. Case reports, review studies and studies pertinent to lab experiments and animal experiments were excluded.
Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Capital Medical University, People’s Republic of China Corresponding author: Youxiang Li, Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Tiantan, Xili, 6, Dongcheng, Beijing, 100050, China. Email: [email protected]
2
Data extraction We extracted clinical data including patient age, patient sex, aneurysm location, aneurysm size, prior rupture, antiplatelet medication, flow-diverter type, aneurysm occlusion rate, procedure-related complications, morbidity and mortality. We calculated the aneurysm occlusion rate, procedure-related complications, morbidity and mortality across these studies, also making note of subgroup analyses for risk factors. Hazard ratios were extracted for each risk factor.
Data analysis Statistical analysis was performed using the Meta package in RevMan 5. The primary outcome measure was the procedure-related complications. Procedure-related complications were classified as early (30 days) and delayed (>30 days). To explain variability in the primary outcome, we defined priori variables: patient sex, patient age, aneurysm size (
Flow-diverter devices in the treatment of intracranial aneurysms: A meta-analysis and systematic review
The Neuroradiology Journal 0(00) 1–6 ! The Author(s) 2016 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/1971400915621321 neu.sagepub.com
Xianli Lv, Hongchao Yang, Peng Liu and Youxiang Li
Abstract Objective: The purpose of this report was to discuss the overall limitations, safety and efficacy of flow-diverter stenting for intracranial aneurysms. Methods: The authors performed a meta-analysis from January 2009 to September 2014 using the terms ‘‘flow diverter’’ and ‘‘intracranial aneurysms.’’ Additional studies were identified through references in each reviewed article. Data extraction, performed independently by the authors, included demographic data, technical and clinical complications, morbidity and mortality, aneurismal occlusion rates related to flow-diverter devices. The analysis was performed using a fixed effect. Results: Twenty-nine studies with 1524 patients and three to 62 months of follow-up were identified for analysis. The overall technical failure and complication rate was 9.3% (95% CI 6%–12.6%). The rate of procedure-related complication was 14% (95% CI 10.2%–17.9%) and 6.6% (95% CI 4%–9.1%) for morbidity and mortality. Fusiform, dissecting and circumferential aneurysm (OR 3.10, 95% CI 0.93–10.37) were significant risk factors for technical failure and complication. Posterior circulation location (OR 4.03, 95% CI 2.45–6.61), peripheral location (OR 2.74, 95% CI 1.52–4.94) and fusiform, dissecting and circumferential aneurysm (OR 1.95, 95% CI 1.15–3.30) were statistically significant risk factors for procedure-related complications. Posterior circulation location (OR 4.39, 95% CI 2.44–7.90) and peripheral location (OR 3.64, 95% CI 1.74–7.62) were statistically significant risk factors for morbidity and mortality. Conclusions: Fusiform, dissecting and circumferential aneurysm, posterior circulation and peripheral locations have greater procedure-related complications.
Keywords Intracranial aneurysm, endovascular treatment, flow-diverter stenting
Introduction
Methods
Complex unruptured aneurysms such as fusiform, large and/or giant, or wide neck, as well as very small aneurysms or blood blister aneurysms that might be untreatable by conventional coiling and recurrences, can be considered amenable to flow-diverter devices.1 However, flow-diverter devices may cause bleeding or ischemic complications, which are a considerable source of neurological morbidity and mortality.2 With an accumulating number of studies of flowdiverter device treatment of intracranial aneurysms, our understanding of its role in endovascular treatment of intracranial aneurysms continues to evolve.2,3 Unfortunately, there is a remarkable degree of heterogeneity in previous studies regarding results and outcomes of flow-diverter devices in the treatment of intracranial aneurysms.3 We performed a metaanalytical review of the literature about their efficacy, safety, limitations and developments.
A PubMed, Embase and Web of Science search using the terms ‘‘flow diverter’’ and ‘‘intracranial aneurysms’’ was performed from January 2009 to September 2014. We incorporated English-language studies including more than five patients treated with flow-diverter devices and follow-up outcome. References in the reviewed studies were also incorporated if the inclusion criteria were met. Case reports, review studies and studies pertinent to lab experiments and animal experiments were excluded.
Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Capital Medical University, People’s Republic of China Corresponding author: Youxiang Li, Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Tiantan, Xili, 6, Dongcheng, Beijing, 100050, China. Email: [email protected]
2
Data extraction We extracted clinical data including patient age, patient sex, aneurysm location, aneurysm size, prior rupture, antiplatelet medication, flow-diverter type, aneurysm occlusion rate, procedure-related complications, morbidity and mortality. We calculated the aneurysm occlusion rate, procedure-related complications, morbidity and mortality across these studies, also making note of subgroup analyses for risk factors. Hazard ratios were extracted for each risk factor.
Data analysis Statistical analysis was performed using the Meta package in RevMan 5. The primary outcome measure was the procedure-related complications. Procedure-related complications were classified as early (30 days) and delayed (>30 days). To explain variability in the primary outcome, we defined priori variables: patient sex, patient age, aneurysm size (
