Intraocular aphakia correction in patients with prior keratorefractive surgery: literature review. Part 1

Introduction . An increasing number of patients with a history of keratorefractive surgeries are presenting to ophthalmologists with complaints of vision loss due to cataracts. Treating this group poses surgeons with a range of unique challenges: high demands for vision quality, complexities in selecting the appropriate intraocular lens (IOL) power calculation formula and IOL model, target refraction, as well as the need to modify cataract extraction techniques and address specific postoperative considerations. Despite advancements in the development of new IOL designs and calculation formulas, clinical and functional outcomes in this group remain inferior to those in patients without prior keratorefractive procedures. A paradigm shift is emerging, advocating for a personalized approach in the diagnosis and management of cataracts in these patients. However, discussing all aspects within a single review proved impractical, leading us to divide it into two parts. The objective of the first part of this study is to assess the specific considerations for aphakia correction in patients who have undergone keratorefractive procedures, based on literature data, while taking into account the long-term complications of refractive surgery. Additionally, this part will address the fundamental principles of the design and functionality of pseudoaccommodating intraocular lenses (IOLs). Materials and methods . A selection of over 200 peer-reviewed publications from resources such as PubMed, eLibrary, CyberLeninka, Science Direct, and Google Scholar over the past 30 years was conducted. The first part of the review includes 49 publications. This work represents an analysis of contemporary literature, reflecting the impact of keratorefractive surgeries on the successful performance of phacoemulsification with IOL implantation. Results . The findings from the first part of the analysis indicate that a detailed medical history of previously performed keratorefractive corrections – specifically their type and potential long-term complications – play a significant role in determining the surgical treatment strategy. Standard examination methods do not always fully reflect the optical characteristics of the cornea in these patients. Extended preoperative assessments, including specialized techniques such as keratotopography and keratotomography, are crucial for identifying corneal irregularities and for the subsequent selection of the type of intraocular lens (IOL) for aphakia correction in patients who have undergone keratorefractive surgeries. Studies show high effectiveness not only in using monofocal lenses but also in the potential application of pseudoaccommodating IOLs, including those with extended depth of focus and multifocal lenses. The selection of optimal formulas for IOL calculation, as well as the clinical aspects influencing refraction in the postoperative period, will be addressed in the second part of the literature review. Conclusion . The increase in the number of refractive surgeries has led to a growing population of patients with cataracts following ametropia correction. This has spurred the development of new IOL variants with extended depth of focus. However, literature data on their effectiveness in patients who have undergone keratorefractive procedures remain limited. Multicenter prospective studies are needed to evaluate new IOL models and to determine the optimal surgical strategies for this category of patients.