Eyeworld

FALL 2024 | EYEWORLD | 37 C YES CONNECT by Ellen Stodola Editorial Co-Director About the physicians Neel Pasricha, MD Assistant Professor of Ophthalmology University of California, San Francisco San Francisco, California Nandini Venkateswaran, MD Assistant Professor of Ophthalmology Harvard Medical School Cornea and Refractive Surgery Service Massachusetts Eye and Ear, Lexington Lexington, Massachusetts advise patients of the risk of refractive surpris- es, even with modern-day formulas. She also advises patients that they will likely need to be in glasses or hard contact lenses after surgery based on the degree of keratoconus/ectasia for best vision. Dr. Pasricha also discussed several challeng- es of performing cataract surgery in patients with keratoconus: intraocular lens selection, choosing the correct formula, and surgical tech- nique modification. Dr. Pasricha said you want to look at the central corneal astigmatism of these patients, which can be broken down to regular or irreg- ular. If it's regular, there are different options. "You could consider doing a standard monofo- cal toric in some cases. Most people, including myself, would opt for a non-toric monofocal," he said. "If you have the LAL [Light Adjustable Lens, RxSight] available, that's a great option for those patients." He noted that the LAL FDA label states it can correct up to 2.75 D of astig- matism but in the real world can achieve more. You ideally want to use a monofocal lens that will treat the negative spherical aberration that the keratoconus induces, Dr. Pasricha said. Keratoconus is similar to hyperopic LASIK in that it causes a central steepening ectasia effect, and that causes negative spherical aberration, he said. The lens you want to go with is either a zero spherical aberration, like the EnVista plat- form (Bausch + Lomb), or an older one that has positive spherical aberration, like the SA60AT (Alcon). If the central corneal astigmatism is irregular, with the classic inferior steepening, you want to find out if the patient wears hard contact lenses, he said. Many of these patients are wearing a scleral lens or rigid gas permeable lens ahead of time. "That's great because it does an amazing job of correcting their irregular astigmatism," he said. "If they do wear a hard contact lens, I like to counsel them that after surgery, they'll need to wear the hard contact lens for their best vision, but the prescription is going to need to be changed." If they don't wear scleral lenses or rigid gas permeable lenses, and they're not planning to Cataract surgery in patients with keratoconus presents a challenge in the presurgical, intra- operative, and postoperative stages. Refractive outcomes are notoriously difficult to predict de- spite careful preoperative planning, and patients with irregular corneas often require postoperative correction with rigid contact lenses for their best visual acuity and quality of vision. Recent develop- ments, such as newer-generation keratoconus-spe- cific IOL formulas and advanced lens technology (including the Light Adjustable Lens and aperture optics), hold promise for improving outcomes for these patients. Yet, significant challenges remain. For this YES Connect column, we queried two experts regarding how they proceed with cataract surgery in patients with keratoconus and how they leverage the latest technology to maximize outcomes for this unique patient population. —Eric Weinlander, MD, Guest Editor, YES Connect W hen performing cataract surgery in patients with keratoconus, there are considerations for surgical planning, lenses, and techniques that surgeons need to account for to ensure success. In this issue's YES Connect column, Nandini Venkateswaran, MD, and Neel Pasricha, MD, discussed how they handle these patients, including testing, formu- las, and IOL selection. Potential problems of preexisting keratoconus Dr. Venkateswaran shared the major challenges in eyes with keratoconus undergoing cataract surgery. There is always the concern for ongoing keratoconus progression. She said to ensure that the keratoconus is stable prior to proceeding with cataract surgery, as ongoing keratomet- ric changes can lead to refractive changes and blurred vision post-cataract surgery. In addi- tion, given the degree of ectasia and possible corneal scarring, the view for cataract surgery can be difficult, and trypan blue to stain the anterior capsule can be helpful. A suture in the main wound is often needed given corneal elasticity changes. Finally, she shared that IOL calculations are an ongoing challenge. She'll Cataract surgery in patients with keratoconus continued on page 38

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