Dorado Beach, Puerto Rico—A topical non-steroidal anti-inflammatory drug (NSAID) can be a valuable tool for cataract surgeons.
However, initiating treatment 3 days preoperatively affords greater benefits to the surgeon and the patient compared with regimens started closer to the time of surgery, said Eric D. Donnenfeld, MD, at the Current Concepts in Ophthalmology meeting.
Dr. Donnenfeld reviewed data from previous studies suggesting there is a dose-response curve for the mydriatic effect of topical NSAIDs.
"Prostaglandins are largely responsible for intraoperative miosis and postoperative inflammation, and so treatment with a topical NSAID that blocks prostaglandin synthesis will help to maintain pupil size, reduce discomfort, and prevent CME.
"However, a topical NSAID offers more than just those benefits because it can improve surgical outcomes, reduce complications, and optimize visual rehabilitation of the cataract patient," said Dr. Donnenfeld at the meeting, sponsored by Johns Hopkins University School of Medicine, Baltimore, and Ophthalmology Times. "As such, NSAIDs should be considered a surgical tool as vital as the choice of phacoemulsification handpiece or viscoelastic in improving cataract surgery outcomes."
A number of studies published over the past several years have investigated the effects of preoperative NSAID use on intraoperative miosis.
Clinical studies evaluating administration of the NSAID beginning 1 hour, 2 hours, 1 day, or 3 days before surgery showed statistically significant efficacy for reducing pupil diameter regression intraoperatively relative to controls, and their results suggested a potential benefit for beginning treatment earlier with respect to minimizing the decrease in pupil size.
"NSAIDs prevent intraoperative miosis by inhibiting cyclooxygenase to prevent prostaglandin synthesis," said Dr. Donnenfeld, associate professor of ophthalmology, New York University, New York, and a partner in a private practice in Long Island, New York. "However, they have no effect on preformed prostaglandins."
A dose-response study Based on that information and recognizing that cataract surgery is more challenging and more likely to result in complications when performed in eyes with small pupils, Dr. Donnenfeld undertook a dose-response study assessing the clinical benefit and relative efficacy of different preoperative dosing regimens when using NSAID treatment as a tool in cataract surgery.
"It is probably intuitively obvious that large pupils make cataract surgery safer and easier. When operating in eyes with a large pupil, I am a superb cataract surgeon, whereas I am mediocre at best in the setting of small pupil surgery," Dr. Donnenfeld said.
A total of 100 patients were randomly assigned into one of four groups to receive placebo or ketorolac tromethamine 0.4% preoperatively either 1) q.i.d. × 3 days plus 1 hour preoperatively (q 15 min × 3 doses); 2) q.i.d. for 1 day plus q 15 min × 3 doses; or 3) q 15 min × 3 doses.
A large number of variables were studied, including intraoperative and postoperative discomfort, mydriasis, surgical time, phacoemulsification time and energy, endothelial cell counts, time to return of best-corrected visual acuity (BCVA), corneal clarity, pachymetry, postoperative inflammation, intraoperative complications, and the development of cystoid macular edema.
"This study was unique in selection of its endpoints because instead of looking just at the effects of the NSAID on mydriasis and pain, I wanted to see if NSAID use made me a better surgeon," Dr. Donnenfeld explained.
The results showed the presence of a dose-response curve with the best outcomes achieved in eyes treated beginning 3 days before surgery.