EyeWorld Asia-Pacific June 2015 Issue

51 EWAP REFRACTIVE June 2015 by Maxine Lipner EyeWorld Senior Contributing Writer Buffing up refractive results in dry eyes Putting a new shine on the ocular surface I t can be par for the course—patients who are dissatisfied with their vision coming in for refractive surgery evaluation often have an underlying dry eye problem, according to William Trattler, MD, Center for Excellence in Eye Care, Miami. “They may have some contact lens intolerance or are just not happy with their vision and are hoping that LASIK would solve their problem,” Dr. Trattler said. “We therefore see a high percentage of patients that come in for refractive surgery consults who have preexisting dry eye.” He finds that this is especially true of contact lens patients. “Contact lens wearers often notice that their vision is not as crisp as they would like and they’re hoping that LASIK can solve their problem,” Dr. Trattler said. Computer use can also be a factor because individuals do not blink as much while using one, he said. “Also, as we get older we have a little more dry eye and as a result, patients commonly experience reduced quality of vision,” he explained. In addition, patients who use oral medications like oral antihistamines for allergies often experience dry eye. Uday Devgan, MD , chief of ophthalmology, Olive View-UCLA Medical Center, and Devgan Eye Surgery, Los Angeles, also finds that allergy medications can play a role. “The surface can be affected by a lot of these allergy drops,” Dr. Devgan said. “Patients who have seasonal allergies or rhinitis may be taking an antihistamine, which often has pseudoephedrine to dry out their mucous membranes but dries the eyes out, too.” For a potential corneal refractive patient, knowing about existing dry eye is even more important, he said. “LASIK or even PRK is going to make everyone’s eyes drier since we are interrupting those corneal nerves,” Dr. Devgan said, adding that even normal eyes are going to be dry for at least a couple of months post-LASIK. Dr. Trattler said it is important to identify dry eye and optimize the ocular surface for PRK patients because the condition can increase the risk for delays in epithelial healing. “Typically with PRK we expect visual recovery in 3–5 days, but it could take longer if dry eyes are not identified and treated preoperatively,” he said. Dr. Devgan urges restraint in working with dry eye patients, regardless of the method of refractive surgery. “Let’s be careful when operating on dry eye patients during the driest, hottest summer months particularly in arid climates like Southern California,” he said. He may recommend that patients use tears to optimize their ocular surface and return in a few months. Preop work With any potential refractive patient, the first step for Dr. Trattler is to determine whether dry eye is present. Usually in younger patients he finds that dry eyes are a form of aqueous deficiency. So preoperatively he will place punctal plugs, begin topical steroid therapy for 1–3 weeks, and start the patient on Restasis (cyclosporine, Allergan, Irvine, Calif.) to enhance the production of tears. Eric D. Donnenfeld, MD , clinical professor of ophthalmology, New York University Medical Center, New York, likewise stresses the importance of vigilance. Preoperatively he tests LASIK patients using the TearLab Osmolarity System (TearLab, San Diego). “We look for anything more than 308 (milliosmoles) or a difference of 8 milliosmoles or greater between the two eyes,” Dr. Donnenfeld said. He added that they also consider MMP-9 readings looking for inflammatory cytokines. If the patient does have preexisting dry eye, Dr. Donnenfeld is aggressive about appropriate treatment. For those with meibomian gland disease, he recommends use of hot compresses, stepping up lid hygiene, use of oral reesterified omega-3 supplements, and administration of artificial tears. In addition, he suggests instituting LipiFlow (TearScience, Morrisville, NC) to heat the lids from the inside and massage out the blocked oil glands. Meanwhile if the patient has aqueous deficient dry eye, Dr. Donnenfeld uses pulse steroid therapy with loteprednol 4 times a day for 2 weeks and then decreases this to twice a day for an additional 2 weeks. He recommends use of Restasis, as well as artificial tears. “We’re also much more aggressive with punctal plugs with LASIK,” Dr. Donnenfeld said. “A lot of the dry eye with LASIK is not inflammatory—it is actually mechanical due to the severing of the corneal nerves.” This makes preserving the patient’s own tears effective, he said, so he uses the collagen plugs from Odyssey Medical (Waltham, Mass.) in this situation. “The recent [FDA] PROWL studies showed that dry eye is very common for at least 3 months after surgery, and these plugs last 3 to 6 months,” Dr. Donnenfeld said. “So while the dry eye is resolving, the plugs are there, and when the corneal sensation returns, the plugs are gone.” For more on the PROWL studies and results, see the “Refractive editor’s corner of the world” column on page 96. Intraoperatively in LASIK cases involving dry eye disease, Dr. Donnenfeld will make flaps as continued on page 52