Microsurgery Treatment as an Optimal Management of Posterior Cerebral Artery Aneurysms: A Systematic Review and Meta-Analysis

Abstract

The choice of treatment of two modalities, open surgical or endovascular, in posterior cerebral artery (PCA) intracranial aneurysms must be taken based on their special characteristics. The objective of this study is to assess the potential superiority in outcomes, operative mortality, and clinical improvement after microsurgical and endovascular management repair in PCA intracranial aneurysms. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), we created this study, performing a systematic investigation on the PubMed database, with the last search carried out on June 12, 2016. The eligibility limitations were that only full text was used in the English language, and double-checking was applied. Extracted data was organized on a standard table form, including first author, publication year, general number of patients and patients at follow-up, mortality rate (with 30 days from the selecting treatment), improvement (showing postoperatively at the clinical progress (muscle strength, thinking ability, and disorientation, due to ischemic infarctions following parent vessel occlusion) for the patients of both modalities. There were eight articles that matched our study criteria. The total study population included 8,863 patients with an aneurysm, 184 (2.07%) of which had an aneurysm at the different segments of the PCA. The pooled results revealed no statistically significant difference between the two groups, in terms of mortality, but with substantial statistical results concerning clinical improvement. We concluded that the aneurysmal site and size do not influence the treatment outcome. However, clinical improvement was a statistically significant factor, demonstrating the superiority of open surgical management over endovascular treatment (EVT) for PCA aneurysms. The selection of the appropriate procedure for every case must be done based on its special characteristics.

Keywords: aneurysms; microsurgery; posterior cerebral artery; posterior cerebral artery aneurysm management; posterior cerebral artery aneurysms.

Figure 1. Flowchart of the study selection process

Figure 2. Forest and funnel plot for improvement

I2: percentage of total variation across studies that is due to heterogeneity rather than chance; CI: confidence interval (A) Forest plot for improvement, with results demonstrating a statistically significant difference between groups (OR: 3.15; 95% CI: 1.20-8.26; p = 0.02), without heterogeneity (p = 0.41; I2 = 3%); (B) funnel plots for improvement in the two groups with no heterogeneity (p = 0.41; I2 = 3%)

Figure 3. Forest and funnel plots for mortality including the study by Taylor et al.

I2: percentage of total variation across studies that is due to heterogeneity rather than chance; CI: confidence interval (A) Forest plot for mortality, with results showing no statistically significant difference between the two groups (OR = 11.16; 95% CI: 0.13, 10.61; p = 0.89) but a high heterogeneity was found (p = 0.05 and I2 = 59%); (B) funnel plot for mortality in the two groups, with the study by Taylor et al.

Figure 4. Forest and funnel plots for mortality without the study by Taylor et al.

I2: percentage of total variation across studies that is due to heterogeneity rather than chance; CI: confidence interval (A) Forest plot for the same parameter without the study by Taylor et al. in 2003 demonstrated an additionally no statistically significant difference between the two groups (OR = 2.46; 95% CI: 0.45-13.45; p = 0.30) but with no heterogeneity (p = 0.29 and I2 = 20%); (B) funnel plot for mortality in the two groups, without the study by Taylor et al.