I want to thank Dr. William Trattler and his staff for an excellent report on the importance of non-steroidal topical anti-inflammatory agents in cataract and refractive surgery ("Topical NSAIDs for Pain and Inflammation," April 2006, p. 56). In the article, Dr. Trattler alluded to some of the reports of epithelial healing problems with Nevanac (nepafenac, Alcon) and its use with PRK. This stimulated two clinical studies that I have been involved with that are being submitted for publication. I want to give a preliminary report of my personal findings in these studies, and my personal experience with topical Nevanac in PRK.
The FDA's approval of all NSAIDs comes with a warning that they can cause delayed wound healing and epithelial toxicity, so it is important that all clinicians monitor eyes closely that are on non-steroidals, especially in cases like PRK, where there is a large epithelial defect. I had personal communication with Dr. Trattler regarding his concerns, so I created two clinical studies.
The first was a randomized, prospective study comparing the epithelialization rate with topical Nevanac, topical Acular LS (ketorolac tromethamine, Allergan) and topical Xibrom (bromfenac, Ista). The three groups of patients were treated with the same NSAID in both eyes. The patients were followed daily with the contact lenses being removed and digital slit-lamp photographs taken daily until epithelialization was complete in all groups. There was no difference in epithelialization rates with any of the NSAIDs. We did find in all three groups a general delay in epithelialization of approximately 24 hours due most likely to the removal of the contact lenses every day and the extra testing, but there did not appear to be any difference in the epithelialization rates with these three medications.
The second study compared Nevanac and Acular LS in a contralateral fashion to study wound healing and pain after PRK. This multicenter study included our center in Kansas City as well as [those of] Drs. Eric Donnenfeld, Ed Holland and Michael Raizman. This study involved 80 eyes of 40 patients, in which one eye was treated with Nevanac and the fellow eye with Acular LS. The contact lenses were not removed until after epithelialization. The results showed that the Nevanac eyes experienced statistically less irritation after treatment on day three, and that the epithelialization rates were equal in both eyes. There was no difference among the four study sites.
Both studies are being submitted for publication where the details will be available. As Dr. Trattler alluded to in his paper, the difference in his experience with Nevanac and mine, including these two studies, may be how the drugs were used in these different studies. In the studies I participated in, we did not apply any of the non-steroidal agents directly onto the raw stromal surface following laser ablation before placement of the bandage contact lens. The NSAIDs were applied, as I do clinically, up to four times a day for the first 48 hours after surgery.
I have been using topical NSAIDs in PRK for over 10 years and have always used them as needed for pain after surgery. I believe with this type of use; we have helped reduce discomfort and have not had significant epithelial wound healing problems. I think cautious use of these medications is warranted, since we do have an open wound on the eye so patients to need to be followed closely.
I again want to congratulate Dr. Trattler on an excellent review, and wanted to add this information to the overall subject.
Sincerely,
Daniel S. Durrie, MD
Kansas City, Mo.