Muller's muscle conjunctival resection versus external levator advancement for ptosis repair: systematic review and meta-analysis

Purpose To compare the outcome of Muller's muscle conjunctival resection (MMCR) versus external levator advancement (ELA) in patients undergoing ptosis surgery. Methods A systematic review and meta-analysis were performed as per the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, and a search of electronic information was conducted to identify all comparative studies of MMCR versus ELA in ptosis repair. The primary outcome measures were the post-operative marginal reflex distance (MRD1), ptosis under-correction, over-correction, and re-operation rate. Secondary outcome measures included cosmetic appearance, complications, operative time, and learning curve. Fixed-effect modelling was used for the analysis. Results Seven studies that enrolled 1038 eyelids were identified in the literature. There was no statistically significant difference between the MMCR and ELA groups in post-operative MRD1 (Mean Difference [MD] = 0.13, P = 0.28) and the rate of under-correction odds ratio [OR] = 0.49, P = 0.14). However, ELA had a significantly higher rate of over-correction (OR = 0.17, P = 0.04) and re-operations (OR = 0.26, P = 0.0001) compared to MMCR. For secondary outcomes, MMCR had an improved cosmetic appearance, lower total number of complications and shorter operation time (MD = − 10.96, P < 0.00001). Finally, the two techniques had no significant difference in the learning curves. Conclusion Both MMCR and ELA are effective techniques for the surgical correction of ptosis; however, MMCR surgery is a more predictable and robust technique compared to, ELA with lower rates of over-correction and re-operation.