Eyeworld

SEPTEMBER 2023 | EYEWORLD | 45 R While keratoconus is the most common reason for using this lens off label for irreg- ular astigmatism, Dr. Bafna said things like Salzmann's nodules and pellucid marginal degeneration can create an irregular amount of astigmatism. Patients with prior RK are also likely to have some irregularity in their cor- nea. "What's hard with RK is there's a lot more variability in terms of the final visual outcome; there's a lot more variability in our calcula- tions," Dr. Bafna said, adding that these patients may also have diurnal fluctuations. There are some patients who may not be ideal candidates for this lens. Dr. Bafna noted that due to the filter in the lens, most patients will get 30–40% less light coming into their eye. If you use it unilaterally, it's important to let pa- tients know that they will notice that there's less light and things will appear dimmer in that eye. "A lot of our patients have monovision prior to cataract surgery," he said, "but before cata- ract surgery, the natural lens gives them a bit of additional range of vision. One technique often used to simulate monovision is to put a monofo- cal lens in both eyes." The whole concept is range of vision, Dr. Bafna said. "A monofocal at near will be good at a particular point, but if you move your hand in and out, it gets out of focus. What's nice about this lens is I can target –1 or –1.25, so I can give patients that entire range of vision." Karl Stonecipher, MD, said he has been familiar with this lens for some time. "On label, we're looking at those patients who are a good monovision fit," he said. "For me, they have less than 2 D of cylinder because the lens neu- tralizes 1.5 D. … I think for that classic depth perception monovision patient who wants great distance, it's a fantastic lens." In patients who have a highly aberrated cornea—whether RK, hexagonal RK, LASIK with decentration, PRK with higher order aberrations and small optical zones, or keratoconus—Blake Williamson, MD, said these patients do excep- tionally well with the lens. He will usually start with the most aberrated eye first to see how the patient does. Dr. Williamson noted that he's generally using the IC-8 Apthera for off-label indications. If you ask most refractive surgeons, if the patient has a healthy cornea and desires presbyopia correction, the surgeon is most likely going to use an EDOF/multifocal/trifocal IOL, he said. The area where there's been a need is in the post-RK, keratoconic, and post-LASIK continued on page 46 Figure 3: Same patient as in Figure 1; current corneal topography of right eye following hyperopic LASIK years prior Figure 4: Same patient as in Figure 1; current corneal topography of left eye following hyperopic LASIK years prior Source (all): Arthur Cummings, MD

• Blank Page