The Effect of Hinge Location on Corneal Sensation and Dry Eye After LASIK: A Systematic Review and Meta-analysis

Dry eye symptoms are a frequent postoperative complication of laser in situ keratomileusis (LASIK). Although estimates of the incidence of dry eye syndrome vary widely, from 3% to 59%, almost all patients will have transient dry eye during the immediate postoperative period.Because of the variability in corneal innervation patterns, altering flap characteristics in LASIK may affect postoperative corneal sensation and dry-eye disease. Some studies have reported that postoperative corneal sensation may be higher and recovery faster in eyes with horizontal flaps (nasal- or temporal-hinge) than in eyes with vertical flaps (superior- hinge). However, some other studies have not established an association between corneal sensation and hinge position. This study reviewed the published literature and performed a meta-analysis aimed to investigate the effects of hinge location on corneal sensation and dry-eye symptoms after LASIK.