Topical 0.1% Bromfenac Sodium for Intraoperative Pupil Dilation Maintenance and Prostaglandin E2 Inhibition in Femtosecond Laser-assisted Cataract Surgery

Since a new generation of femtosecond lasers became available for cataract surgery in 2009, the use of this image-guided system has provided several benefits, including a reduction in phacoemulsification energy by prefragmentation of the crystalline lens, and the potential advantages of more precise corneal incisions and capsulotomy formation. However, as with any new surgical technique, femtosecond laser cataract surgery also has potential complications. Intraoperative miosis is one of the most common intraoperative complications of femtosecond laser-assisted cataract surgery, with a reported prevalence ranging from 9.5 to 32.0%. Significant pupillary constriction necessitates the removal of the anterior capsule flap, fragmented nucleus and remaining cortex, which is potentially associated with a higher rate of surgery-related complications.

Intraoperative miosis may be due to the intraocular effects that occur after femtosecond laser pretreatment. The intraocular tissues may be exposed to laser emissions, and lens proteins can be released into the anterior chamber. Together, these events trigger the release of unwanted cytokines. In a previous study, intraocular prostaglandin concentrations were found to be increased immediately after femtosecond laser pretreatment. Prostaglandins, especially prostaglandin E2 (PGE2), are known to play a role in inflammation-induced miosis.

Preoperative topical treatment with NSAIDs inhibits the release of prostaglandins in response to surgically-induced miosis by suppressing cyclooxygenase, the enzyme that transforms arachidonic acid into prostaglandin precursors. The effectiveness of ophthalmic NSAIDs in preventing miosis has been well documented in conventional phacoemulsification cataract surgery. However, whether this effect is also applicable to femtosecond laser-assisted cataract surgery is unknown. Yeoh has suggested the addition of NSAID eye drops to the dilation regimen during femtosecond laser cataract surgery, but no randomized study has been conducted to support this theory. Given the increasing popularity of femtosecond laser-assisted cataract surgery, the investigators sought to study whether topical NSAIDs might be beneficial in pupil maintenance and PGE2 inhibition during the procedure.