EyeWorld Asia-Pacific June 2017 Issue

June 2017 28 EWAP SECONDARY FEATURE Zonules after TriMoxi injection Source (all): G. Auffarth, MD Going dropless by Stefanie Petrou Binder, MD EyeWorld Contributing Writer Experts discuss the pros and cons of “dropless” cataract surgery I f it’s not broken, why fix it? But when the advantages of the new override the tried and true, we pay attention. The application of an antibiotic/ corticosteroid combination into the vitreous body or the anterior chamber after cataract surgery has shown decided advantages for patients in the postoperative period, including warding off infection, inflammatory control, patient convenience, and guaranteed compliance, not to mention appreciably lower costs. Stewart Galloway, MD , Cumberland Eye Care, Crossville, AT A GLANCE • The application of an antibiotic/ corticosteroid combination into either the vitreous body or the anterior chamber after cataract surgery has shown decided advantages for patients over topical application. • Transzonular drug application is safe once you learn the technique. • TriMoxi is extremely effective in the prevention of inflammation, CME, and endophthalmitis following cataract surgery. • Intracameral drug application using dexamethasone and moxifloxacin is safe and effective and allows the surgeon to assess a patient’s vision right after surgery. • There is no learning curve using intracameral drugs and they offer a superior method of endophthalmitis prophylaxis. • It’s not recommended to use TriMoxi in the anterior chamber. Tennessee, and Francis Mah, MD , director of corneal and external disease and co-director of refractive surgery, Scripps Clinic, La Jolla, California, spoke to EyeWorld about which method they use and why. Transzonular approach A controversial method of administering prophylactic meds after cataract surgery involves the transzonular injection of a triamcinolone/ moxifloxacin combination, TriMoxi (Imprimis Pharmaceuticals, San Diego) into the anterior vitreous, with or without vancomycin (TriMoxiVanc, Imprimis Pharmaceuticals). While some surgeons prefer to avoid any unnecessary manipulation of the zonule fibers due to concerns of preserving their structural integrity and potentially creating new problems in the eye, Dr. Galloway sees this as a misconception. “My own personal approach is almost 100% transzonular. It is very safe and does not damage the zonules. The biggest disadvantage of the approach is that some surgeons might not feel comfortable about going through the zonules, because we are taught in training not to damage the zonules and be wary of going into the vitreous. But, it is very safe once you learn the technique and know how to do it. I don’t see any other disadvantage, whatsoever,” he said. Dr. Galloway and his colleagues have successfully used TriMoxi for cataract surgery in about 20,000 eyes. His technique involves gently stretching the Transzonular TriMoxi injection ciliary sulcus and zonules with viscoelastic and directing the cannula under the iris and above the anterior capsule. The cannula is then advanced through the zonules, which separate but do not break, and into the vitreous. A visual movement or release of the lens capsule sometimes confirms zonular penetration. TriMoxi is injected slowly and at a constant rate. “The pars plana approach is also very effective and quite prominent in the U.S. The only downside is that there can be some discomfort to the patient. In addition, anatomically we don’t always know the exact location of the pars plana. In some patients, it is more anterior or posterior, and since we are applying a standard, injecting 2.5–3 mm back, finding the pars plana won’t be perfectly precise. It is essentially a blind maneuver, which is why I choose to inject transzonularly. Still, I don’t think there is any huge disadvantage to the pars plana approach, other than making another opening into the eye. With a transzonular approach, you are already in the eye to remove the cataract,” Dr. Galloway said.