Clipping versus coiling in the treatment of oculomotor nerve palsy induced by unruptured posterior communicating artery aneurysms: a meta-analysis of cohort studies

Abstract Background Although the superiority of clipping compared to coiling on the oculomotor nerve palsy (ONP) recovery for ruptured posterior communicating artery aneurysms (PcomAAs) has been widely accepted, which treatment modality is better in the treatment of ONP induced by unruptured PcomAAs still remains unclear. Methods A meta-analysis of studies that compared clipping with coiling was performed after a literature search. Perioperative data and clinical outcome were extracted. Analysis on the effect of the two treatment modalities was then performed. Results Nine eligible studies with a total of 136 patients met the inclusion criteria. There was a significant difference in the total efficiency (any degree of improvement) on ONP favoring clipping [RR= 1.21, 95%CI (1.01, 1.44), p = 0.04], the effect was most notable for complete recovery of ONP after having suffered preoperative partial palsy [RR= 0.72, 95%CI (0.55, 0.95), p = 0.02]. There was neither a significant difference regarding the complete recovery of ONP [RR= 1.11, 95%CI (0.77, 1.61), p = 0.58] nor the frequency of complications [RR= 0.07, 95%CI (0.00, 1.10), p = 0.06]. Also when subdividing there was no significant difference in complete recovery of ONP in patients who had initially suffered a complete ONP [RR= 0.79, 95%CI (0.38, 1.64), p = 0.53] and partial ONP [RR= 1.16, 95%CI (0.65, 2.08), p = 0.61] between clipping and coiling. Conclusions A superiority of clipping over coiling for the improvement of ONP secondary to unruptured PcomAAs was found. Patients with partial ONP were more likely to attain a complete resolution of ONP, as compared to complete ONP.