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.