Cystoid macular edema after femtosecond laser–assisted versus phacoemulsification cataract surgery

Purpose: To evaluate the incidence of postoperative clinical cystoid macular edema (CME) associated with femtosecond laser–assisted cataract surgery (Catalys laser system) versus phacoemulsification cataract surgery.

Setting: Launceston Eye Institute, Launceston, Tasmania, Australia.

Design: Nonrandomized, single-surgeon, prospective, comparative cohort case series.

Methods: Patients who had femtosecond laser–assisted cataract surgery and phacoemulsification cataract surgery between March 2012 and July 2014 were included in the study. The femtosecond laser–assisted cataract surgery group had anterior capsulotomy, lens fragmentation, with or without corneal incisions via femtosecond laser pretreatment. Standard phacoemulsification surgery and foldable acrylic intraocular lens insertion proceeded in all cases. All patients received topical nonsteroidal drops commencing 2 days preoperatively and continuing for 4 weeks postoperatively. The incidence of postoperative clinical CME (confirmed by optical coherence tomography) and comparison between groups were measured. The main outcome measure was the clinical CME rates.

Results: Of the eyes, 833 had femtosecond laser–assisted cataract surgery amd 458 had standard phacoemulsification cataract surgery. Both groups had similar baseline parameters. There were 7 cases of postoperative CME (0.8%) in the femtosecond laser–assisted cataract surgery group compared to 1 case (0.2%) in the phacoemulsification cataract surgery group, highlighting a trend toward greater cystoid macular edema in the femtosecond laser–assisted cataract surgery group. This correlated with a change in laser treatment speed (due to a software upgrade), suggesting that retinal safety thresholds need further careful analysis.

Conclusion: Increased CME might be a subthreshold retinal injury safety signal after femtosecond laser pretreatment and warrants further study.