Re: “Safety Profile of Stromal Hydration of Clear Corneal Incisions with Cefuroxime in the Mouse Model” by Moosajee et al. ( J. Ocul. Pharmacol. Ther . 32:469–475,2016)

Moosajee et al. tested the reliability of corneal stromal hydration with cefuroxime in a mouse model. The procedure was not coupled with any intraocular surgery such as phacoemulsification. The authors studied the corneal morphology, histology, and levels of apoptotic cell death after clear corneal hydration by using 1 mg/0.1 mL solution of cefuroxime. They revealed that the use of cefuroxime for clear corneal hydration is safe and its bactericidal effect continued up to 24 h postoperatively. ¹

We would like to make a comment as we have an unusual experience after starting the hydration of corneal stroma from clear corneal incision with the standard dose of cefuroxime during phacoemulsification. Early postoperative macular edema occurred in 8 of our 148 patients after uneventful phacoemulsification during a 3-month period. ² We could not identify any risk factor initially. ³ Upon cessation of inflating clear corneal incision with cefuroxime (1 mg/0.1 mL), no new case with macular edema was recorded. Early postoperative macular edema was then attributed to hydration of corneal incision with cefuroxime. ² Stromal hydration of cefuroxime may exacerbate edema and inflammation in the cornea that is already compromised by phacoemulsification. Corneal inflammation may generalize and this situation probably triggers retinal inflammation and edema.^2,4 We postulated that not only dilution errors but also the method of injection of cefuroxime in the course of phacoemulsification may induce adverse effects. ²

The authors showed that cefuroxime can be detected up to the postoperative 7 days in cornea samples. ¹ Considering also that cefuroxime is one of the most free radical-involving preparations used during phacoemulsification, ⁵ it would be very interesting to know its tissue effect after stromal corneal hydration coupled with phacoemulsification that is the common clinical practice. Broadening the range of the experiment and examination of the other parts of the globe such as retina after corneal stromal hydration with the drug in an animal model would probably be the subject of another interesting study.