Abstract and Introduction
Purpose of Review: Corneal refractive surgery has achieved spectacle-free vision for millions of patients, but this aging population is now developing cataracts. Many of these patients may wish to avoid reliance on glasses after cataract surgery. Presbyopia-correcting intraocular lenses (IOLs) offer a solution, but corneal changes after refractive surgery may compound higher order aberrations and dysphotopic symptoms associated with these IOLs. This review aims to discuss potential factors that could aid in determining suitable postkeratorefractive candidates for presbyopia-correcting IOLs.
Recent Findings: Studies investigating which preoperative measures influence outcomes are lacking. The few studies that have examined presbyopia-correcting IOLs in postkeratorefractive patients report that satisfactory outcomes are possible. However, recommendations for preoperative thresholds appear limited to expert opinion and studies involving virgin corneas.
Summary: As the number of presbyopia-correcting IOLs and postkeratorefractive patients grows, continued investigation into relevant preoperative factors and appropriate IOLs is required to make evidence-based decisions. The current literature shows that with rigorous counseling and appropriate patient selection, presbyopia-correcting IOLs can provide postkeratorefractive patients with satisfactory results and spectacle independence. In addition, the development of postoperative modifiable IOLs may prove to be the preferred option.
Corneal refractive surgery has been performed for decades, helping millions of patients achieve clear, glasses-free vision. Many of these patients are now developing cataracts, and due to a variety of factors, postkeratorefractive patients tend to undergo cataract surgery earlier than patients with virgin corneas. Self-selecting as a group that prioritizes spectacle independence, many of these younger postkeratorefractive patients maintain higher expectations for their refractive outcomes following cataract surgery.
Presbyopia-correcting intraocular lenses (IOLs), such as multifocal IOLs (MFIOLs) and extended depth of field (EDOF) IOLs, have been shown to provide higher rates of uncorrected intermediate and near vision and, therefore, higher rates of spectacle independence than monofocal IOLs. However, many of these presbyopia-correcting IOLs are associated with an increased risk of dysphotopsias and a decrease in contrast sensitivity. Patients who achieve 'perfect' surgical results may still be dissatisfied with their outcomes. Demanding patients with high expectations are unlikely to tolerate the dysphotopsias and visual disturbances associated with presbyopia-correcting IOLs. Properly counseled and amenable patients, who understand the compromises of these IOLs, are ideal.
Patients should be aware that Food and Drug Administration (FDA) premarket approval trials for all presbyopia-correcting IOL implants were exclusively conducted on virgin corneas, and trials for the AcrySof Panoptix (Alcon Laboratories, Fort Worth, Texas, USA) and Tecnis Symfony (Abbott Medical Optics, Inc., Santa Ana, California, USA) showed complaints of some degree of dysphotopsia, such as glare, halo, or starburst, in around 40–50% of patients with 20–30% failing to achieve complete freedom from glasses.[5,6] The FDA approved and other presbyopia-correcting IOLs discussed are presented in Table 1.
Although previous corneal refractive surgery is not an absolute contraindication for presbyopia-correcting IOLs, it does provide several challenges that require additional evaluation and counseling. The challenges associated with presbyopia-correcting IOLs in postkeratorefractive patients have not been quantified, and no comprehensive guidelines exist for determining which patients make suitable candidates. In addition, nonstandardized reporting of results limits interstudy comparisons and efforts to establish guidelines. The IOL power calculations for these patients pose a further challenge; however, this review aims only to discuss potential screening thresholds and other considerations when determining postrefractive candidates for presbyopia-correcting IOLs.
Curr Opin Ophthalmol. 2021;32(1):45-53. © 2021 Lippincott Williams & Wilkins