Endovascular treatment has increasingly been used for aneurismal subarachnoid aneurismal hemorrhage. The aim of this analysis is to assess the current evidence regarding safety and efficiency of clipping compared with coiling. We conducted a meta-analysis of studies that compared clipping with coiling between January 1999 and July 2012. Comparison of binary outcomes between treatment groups was described using odds ratios (OR; clip versus coil). Four randomized controlled trials and 23 observational studies were included. Randomized controlled trials showed that coiling reduced the 1-year unfavorable outcome rate (OR, 1.48; 95% confidence interval [CI], 1.24-1.76). However, there was no statistical deference in nonrandomized controlled trials (OR, 1.11; 95% CI, 0.96-1.28). Subgroup analysis revealed coiling yielded better outcomes for patients with good preoperative grade (OR, 1.51; 95% CI, 1.24-1.84) than for poor preoperative patients (OR, 0.88; 95% CI 0.56-1.38). Additionally, the incidence of rebleeding is higher after coiling (OR, 0.43; 95% CI, 0.28-0.66), corresponding to a better complete occlusion rate of clipping (OR, 2.43; 95% CI, 1.88-3.13). The 1-year mortality showed no significant difference (OR, 1.07; 95% CI, 0.88-1.30). Vasospasm was more common after clipping (OR, 1.43; 95% CI, 1.07-1.91), whereas the ischemic infarct (OR, 0.74; 95% CI, 0.52-1.06), shunt-dependent hydrocephalus (OR, 0.84; 95% CI, 0.66-1.07), and procedural complication rates (OR, 1.19; 95% CI, 0.67-2.11) did not differ significantly between techniques. Coiling yields a better clinical outcome, the benefit being greater in those with a good preoperative grade than those with a poor preoperative grade. However, coiling leads to a greater risk of rebleeding. Well-designed randomized trials with special considerations to the aspect are needed.
