Implementing a Dropless Approach
Postoperative prevention of infection and suppression of inflammation after cataract surgery is best accomplished through a "dropless" approach, according to Jeffrey Todd Liegner, MD, of Eye Care Northwest in Sparta, New Jersey.
With dropless surgery, the surgeon places medication -- antibiotics and/or steroids -- in or around the eye at the time of surgery to reduce or eliminate the need for postoperative eyedrops. The delivery can be by subconjunctival or sub-Tenon's injection, intracameral irrigation, or intravitreal depot placement. Administration of available products varies.
"Dropless surgery improves prophylaxis against infection, offers preemptive control of inflammation in the hands of the surgeon, provides better therapeutic compliance, entails less overall cost to the patient and insurer, and simplifies communication with the patient about postoperative care," Dr Liegner said in his "Hot Topics" presentation at the American Academy of Ophthalmology (AAO) 2015 Annual Meeting.
According to Dr Liegner, the product that provides the greatest ease of use, less waste, and lowest risk for contamination or complication is a compounded drug made of a long-acting steroid and an effective broad-spectrum antibiotic, with coverage for gram-positive organisms, if desired. It is sterile and preservative-free, and is delivered into the vitreous as a transzonular or pars plana injection at the conclusion of the surgery, he said.
Tri-Moxi contains 15-mg/mL triamcinolone acetonide and 1-mg/mL moxifloxacin hydrochloride in a single dose of 0.15 to 0.22 cc. Tri-Moxi-Vanc contains the identical drug formulation with the addition of 10-mg/mL vancomycin.
Tri-Moxi and Tri-Moxi-Vanc are produced by US Food and Drug Administration (FDA)-registered compounding pharmacies. They are proprietary formulations (patents are pending) that are buffered and stabilized. The usual drug dose is 3-mg triamcinolone, 0.2-mg moxifloxacin, and 2-mg vancomycin. Tri-Moxi and Tri-Moxi-Vanc are inexpensive compared with conventional pharmaceuticals, Dr Liegner added.
Compounding Pharmacies Well Regulated
Surgeons do not need to be concerned about the fact that Tri-Moxi and Tri-Moxi-Vanc are produced by compounding pharmacies, Dr Liegner indicated.
"Compounding pharmacies are no longer a dirty word. They must comply with FDA mandates," he said.
The Drug Quality and Security Act (DQSA) enacted in 2013 obligates compounding pharmacies to comply with current Good Manufacturing Practices. The DQSA ensures that the quality of compounded products is equivalent to that of drugs manufactured by big pharmaceutical companies, he emphasized.
The DQSA also created a new section 503B in the Federal Food, Drug, and Cosmetic Act, under which a compounder can become an "outsourcing facility." Under 503B, the government grants interstate shipping, eliminates the need for individual prescriptions, and requires frequent inspections and reporting.
"Most large compounding pharmacies, including Imprimis, are moving to this," he said.
Infection Risk Greatly Reduced
Compared with eye drops, dropless cataract surgery carries a greatly reduced risk for endophthalmitis, Dr Liegner reported.
The medical literature cites the rate of postoperative endophthalmitis following cataract surgery as 70/10,000 (0.70%) with antibiotic eyedrops alone, 25/10,000 (0.25%) with eyedrops plus povidone eyelid scrub, and 4/10,000 (0.04%) with povidone scrub plus intracameral antibiotics.
"Povidone provided a three-fold improvement. With povidone scrub and intracameral antibiotics, we reduced the risk 6 to 7 times further," Dr Liegner said. "But with povidone plus Tri-Moxi intravitreal injection, the anecdotal rate reported by surgeons using this product is only 0.2/10,000 (0.002%)."
He reminded attendees of the risk factors for postoperative endophthalmitis: prior vitrectomy, glaucoma surgery, and corneal transplant, along with presence of diabetes, compromised immunity, blepharitis, ocular trauma, and dialysis.
Medscape Ophthalmology © 2015 WebMD, LLC
Any views expressed above are the author's own and do not necessarily reflect the views of WebMD or Medscape.
Cite this: Advantages Claimed for Dropless Cataract Surgery - Medscape - Dec 21, 2015.