EyeWorld Asia-Pacific June 2015 Issue

June 2015 23 EWAP FEATURE designed to move in the eye, this can result in changes in the optic position and tilting of the optic in response to aggressive healing responses,” Dr. Dell said. Meanwhile, side effects associated with multifocals are well described and may include glare, halos, or unwanted images. Dr. Donnenfeld said the first thing you need when dealing with options for presbyopic patients is to have informed consent from the patient about what the visual realities of the different types of IOLs are. For the accommodating IOL, Dr. Donnenfeld said there is less risk of glare and halo, but there is also less reading function. Often, he has to do a mild monovision to give the patient significant reading function. Additionally, because the lens is more flexible, the refractive results at distance are not as accurate as conventional IOLs, so patients have to understand that there is an increased risk that they made need a laser enhancement to correct for residual refractive error. “The good news is there’s very little loss of contrast sensitivity,” he said. With multifocal IOLs, there will be more reading ability, but these are not truly multifocal IOLs, Dr. Donnenfeld said. They are truly bifocal IOLs, so they get a near point and a distance point, and intermediate distances may be out of focus. “They also have more glare and halo at night,” he said. Multifocal IOLs require good lighting and are dependent on quality refractive outcomes. The most important thing for all of the IOLs available is the preoperative evaluation of the patient and the informed consent, he said. “Patients have to have a reasonable set of expectations before surgery,” Dr. Donnenfeld. With that said, he uses a group of concepts known as the “5 Cs” to achieve optimal results. These include managing cylinder and refractive error; managing the corneal surface and especially dry eye; making sure the capsule is clear; avoiding cystoid macular edema (CME); and centering the IOL on the pupil and the visual axis. Ocular surface Dr. Donnenfeld evaluates the ocular surface in all patients. Dry eye testing is the first step. If he finds that a patient does have some form of dry eye disease, it is important to treat it aggressively before surgery. For patients who have aqueous deficient dry eye, he may use loteprednol or cyclosporine drops. For those with meibomian gland disease, hot compresses or omega-3 fish oils may help. Problems with the ocular surface can have an impact on these lenses. “I think it’s well described that multifocal IOLs in particular are more susceptible to degradation in performance when the ocular surface is less than ideal,” Dr. Dell said. The surgery, including all the topical medications, incisions in the cornea, and manipulation of the eye, can tip the balance in a negative direction in any eye teetering on poor ocular surface health, he said. Residual astigmatism Dr. Dell said residual astigmatism is more of a factor with multifocal IOLs than with accommodating IOLs. At this time, it is uncertain how extended depth of focus lenses will be affected by residual astigmatism. Even half a diopter can affect the performance of a multifocal IOL. “We tend to be very aggressive at treating those small refractive errors,” he said. For residual astigmatism after surgery, Dr. Gupta favors PRK enhancement. Many patients getting these lenses are older and may have subtle anterior basement membrane dystrophy, which could be a problem with a limbal relaxing incision (LRI). Any laser surgery can increase risk of dry eye, but an LRI can do the same as well as create chronic foreign body sensation. “I like the precision of PRK and laser vision correction in general,” she said. Dr. Donnenfeld said for small amounts of cylinder in a patient with no spherical refractive error, astigmatic keratotomy is commonly done. If the patient has a spherical component, IOL exchange or PRK/ LASIK may be used to resolve refractive error. “Refractive cataract surgeons have to be willing and able to perform adjustments in refractive error because it’s crucial to achieve optimal results,” he said. Explanting the lens Lens explanation/exchange is a definite possibility for larger refractive errors or for any patient that has intolerable visual disturbances, Dr. Gupta said. “Try to make the surgery as least traumatic as possible,” she said. Protecting the endothelium is important, as is having a good plan of how you are going to free up and cut the lens, she said. Additionally, Dr. Gupta stressed that counseling patients is vital. Any number of problems can occur in a lens exchange, she said. Dr. Dell said that for small residual refractive errors, he prefers to use laser vision correction. “If there’s a large refractive error, particularly hyperopic, we tend to do an IOL exchange or even a secondary piggyback IOL to rectify the situation,” he said. Lenses built on the single-piece acrylic platform are easily removable in the early postoperative period, he added. Resolving other problems before doing an explantation is key, Dr. Donnenfeld said. “[With] presbyopic IOLs, specifically multifocal IOLs, patients are by far the happiest patients and the most unhappy patients I have in my practice,” he said. “It’s our responsibility to maximize patients’ opportunity to achieve good results, but it’s still difficult to predict whether a patient will be happy or unhappy with a simple preoperative evaluation.” EWAP Editors’ note: Dr. Gupta has financial interests with TearScience (Morrisville, NC), Allergan (Irvine, Calif.), Bio- Tissue (Doral, Fla.), and Shire (St. Helier, NJ). Dr. Donnenfeld has financial interests with Alcon (Fort Worth, Texas), Abbott Medical Optics (AMO, Abbott Park, Ill.), Bausch + Lomb (B+L, Bridgewater, NJ), and Allergan. Dr. Dell has financial interests with AMO and B+L. Contact information Dell: steven@dellmd.com Donnenfeld: ericdonnenfeld@gmail.com Gupta: preeya.gupta@duke.edu