Refractive surgeons should be aware of the possibility that a surgical marker pen (Codman, Johnson & Johnson) could be a cause of diffuse lamellar keratitis (DLK) after LASIK, said Wei-Han Chua, MD.
Dr. Chua reported on a cluster of nine cases of DLK that occurred at the Singapore National Eye Centre. All eyes had undergone LASIK or flap relift/repositioning on a single day, July 24, 2007, and DLK of varying grades was noted on the first postoperative day.
To investigate the outbreak, a review was undertaken of all LASIK procedures performed over the 4-day period from July 23 to 26, 2007. DLK occurred in 9 of 12 eyes that had surgery on July 24th with use of the surgical marker pen and in none of 113 eyes operated on during the other 3 days when a surgical marker pen from another manufacturer was used to ink the corneal marker. Dr. Chua postulated that one or more of the constituents of the ink in the surgical marker pen in question might have incited the inflammatory response.
"It can be difficult to identify risk factors or causative agents in DLK, even when outbreaks occur. However, because of the use of strict protocols for recording the introduction of all new equipment and consumables used for LASIK procedures, we could determine that the introduction of a new brand of surgical markers was the only change made to the surgical regimen on the day the DLK eyes had their procedures," Dr. Chua said.
"To our knowledge, this is the first report of DLK associated with a surgical marker. After we communicated our experience, the manufacturer replied that the surgical marker is intended for use only on the skin and is not meant to be used on the eyes," he concluded.