38 EWAP DECEMBER 2023 REFRACTIVE him is the lens only goes down to 10 D. For extreme myopes, particularly those with keratoconus, there might not be a lens power for that. However, Dr. Williamson noted that he did a case where he was anticipating a myopic surprise and was very straightforward with the patient about this. However, the patient came back 20/15 J2 several days postop with the IC-8 Apthera. “Sometimes that pinhole can gobble up a lot of refractive error, not just coma and astigmatism, but even sphere,” he said. Dr. Cummings has about 8 years of experience with the IC-8 Apthera. He said he mostly uses it when patients are dissatisfied with their quality of vision. “If someone had previous corneal refractive surgery and immediately after experienced glare and halos, it is likely from corneal origin,” he said. “If they did well initially and only became symptomatic once the cataract was diagnosed, the visual symptoms are likely from the cataract. Devices like the iTrace [Tracey Technologies] are useful for both patients and surgeons, making complicated optics understandable and showing both parties where the main issue lies. Is the greatest source of higher order aberrations external (cornea and tear film) or internal (lens and vitreous)? Address the source of greatest error first and explain to the patient that the vision will not be perfect until both have been addressed.” In the case where further corneal surgery is either impossible or unwanted, using the IC-8 Apthera can improve the overall wavefront from internal and external sources, Dr. Cummings said. Dr. Cummings did note that someone with a perfect cornea might consider less light with the IC-8 Apthera to be an issue if they have not seen a significant reduction in glare and halos because there were no corneal higher order aberrations to start with. “The IC-8 Apthera works well in cases with corneal aberrations, including keratoconus, post - RK, post - decentered corneal ablations, or cases with irregular astigmatism,” he said. “I have also found that patients with amblyopia often gain more vision than I would have expected, perhaps due to addressing the ‘crowding effect’ with the small aperture IOL.” Technique considerations Dr. Bafna said part of the approval process for surgeons who want to use this lens is they’re required to read about how to do a YAG because it’s a little different for this lens. The company asks you to YAG in a specific manner in these cases. “If you do it the normal way, patients will have floaters after the YAG,” he said. “In these patients, because they’re looking through this small, 1.6 mm aperture, if there are any floaters in the middle, it’s going to have a bigger impact on the patient’s overall vision.” Dr. Cummings also said it’s important to be very particular with the YAG laser, avoiding laser pulses in the center of the mask. “It is advised to laser outside of the mask with the hinge inferiorly, and after the YAG laser capsulotomy, ideally the posterior capsule will flop posteriorly and hang inferiorly out of the pathway of the incoming light beams,” he said. “On occasion, this won’t go entirely according to plan, then you must do the YAG through the aperture in the center of the mask to detach the posterior capsule from the IOL surface. A small nick in the IOL is more symptomatic here, so it is important to take extra care.” He also said to determine your surgically induced astigmatism with this IOL, as the incision size is bigger than usual at 2.7 mm, and sometimes even larger. The IOL performs well if the final astigmatism is <1.5 D, Figure 3. Current topography of right eye following hyperopic LASIK years prior. Figure 4. Current corneal topography of left eye following hyperopic LASIK years prior. Source (all): Arthur Cummings, MD
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