June 2019

REFRACTIVE

Pharmaceutical focus
Intracameral antibiotics at the end of cataract surgery


by Maxine Lipner EyeWorld Senior Contributing Writer

When it comes to protecting cataract patients from postop infection, many practitioners rely on intracameral injections at the end of surgery to stave off endophthalmitis, according to Richard Lindstrom, MD.
In the U.S., moxifloxacin is the staple, while in Europe most practitioners use cefuroxime, Dr. Lindstrom noted. This is because the European Society of Cataract & Refractive Surgeons (ESCRS) study used intracameral cefuroxime to forestall bacteria such as Staph epidermidis, but in the U.S. the impression is that moxifloxacin is better for this. “Moxifloxacin has been used in studies in Latin America, India, and elsewhere with good outcomes, and most U.S. surgeons were using a fluoroquinolone already topically,” Dr. Lindstrom said.
Eric Donnenfeld, MD, pointed out that until 1.5 years ago vancomycin was commonly used in the U.S. intracamerally. “Then there were some papers on the development of hemorrhagic occlusive retinal vasculitis (HORV), and the use of vancomycin has decreased dramatically,” Dr. Donnenfeld said, adding that this rare condition can potentially lead to bilateral blindness since its delayed onset generally doesn’t occur until after the second eye has been treated. Many now think this is not worth the risk.
The problem with intracameral antibiotics in the U.S. is that no medication has been FDA approved for this. “By definition they’re all off-label compounded medications, and there’s always the risk of contamination with a compounded medication as well as of dilution errors,” Dr. Donnenfeld said. “However, moxifloxacin is particularly safe in that it’s tolerant of higher concentrations.”
There haven’t been any immune responses or any vasculitis, he continued, adding that there have been some reports of pigmentary changes to the iris. “But the risk/reward ratio for moxifloxacin is in favor of the reward,” Dr. Donnenfeld said. “Using it can have a significant impact on reducing the risk of endophthalmitis.”
Dr. Lindstrom pointed out that most errors occur when the injection is prepared by the physician or nurse instead of a compounding facility. “If you work with a high quality, reputable compounding pharmacy with a long track record of quality work, I am comfortable with it,” he said. “I’ve used compounded injections of moxifloxacin made by the Phillips Eye Institute, Imprimis, and Leiters.”
The biggest risk with moxifloxacin in his view is that at too high a concentration, this can be endothelial cell toxic. Two ways this can be avoided are to inject a small amount of 0.1 ml or less into the eye or to make sure this is properly diluted. “From quite a bit of research, it appears that in a concentration of 500 mg per ml, which is a 10-to-1 dilution, it is safe,” Dr. Lindstrom said. “But if you’re using the full-strength 5,000 mg per ml, you have to appreciate that this can be toxic to the corneal endothelium.”
Dr. Lindstrom currently relies on the intracameral injection after cataract surgery without use of supplemental antibiotic drops. “I’m also dropless with regard to the steroid because I inject a small amount of dexamethasone solution intracamerally,” he said, adding that he does use a topical NSAID to reduce inflammation, pain, and the potential risk of clinically significant CME. He puts patients on nepafenac (Nevanac, Novartis) once a day or if that’s not available, bromfenac (Prolensa, Bausch + Lomb) also once a day or in some cases BromSite (Sun Pharmaceuticals) twice a day. If cost is a factor, he will turn to generic ketorolac. Although it is labeled as a four-times-a-day agent, he has patients use it twice a day for 2 weeks, then once a day until the bottle is gone. In some cases, he may use a single bottle of compounded drops that can contain an antibiotic, a steroid, and an NSAID.
Dr. Donnenfeld still frequently prescribes postoperative drops, predominantly in cases involving corneal incisions. He generally likes besifloxacin because it has the best activity against methicillin-resistant Staphylococcus aureus of all of the fluoroquinolones. “I use that twice a day, and if a patient wants a generic, I tend to use ofloxacin,” he said.
The use of intracameral antibiotics in the U.S. is not yet the standard of care as it is in Europe, Dr. Donnenfeld said, adding that the real difference is its approval in Europe. “An ASCRS study looked at the reason ophthalmologists don’t use intracameral, and it’s because it is not FDA approved,” he said. “I think this will become the standard of care in the future once it is FDA approved.”

About the doctors

Eric Donnenfeld, MD
Ophthalmic Consultants
of Long Island
Garden City, New York

Richard Lindstrom, MD
Minnesota Eye Consultants
Minneapolis

Financial interests

Donnenfeld: Alcon, Allergan, Bausch + Lomb, Novartis
Lindstrom: Alcon, Allergan, Bausch + Lomb, Novartis, Sun Pharmaceuticals

Contact information

Donnenfeld: ericdonnenfeld@gmail.com
Lindstrom: rllindstrom@mneye.com

Intracameral antibiotics at the end of cataract surgery Intracameral antibiotics at the end of cataract surgery
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2019-06-04T07:35:21Z
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