Abstract
Small incision lenticule extraction (SMILE) is a “flapless” keratorefractive surgery with excellent safety, efficacy, stability, and predictability for myopia correction. A recent global multicenter study also reported good refractive outcomes for hyperopic SMILE. SMILE has shown advantages including improved biomechanical strength, fewer dry eye symptoms, less corneal denervation, and fewer surgery-induced higher-order aberrations over laser in situ keratomileusis (LASIK). However, night vision complaints, including glare, halos, and starbursts, could still occur after SMILE. These symptoms have been proven to be closely related to the effective optical zone (EOZ), which is defined as the achieved area of corneal ablation. A larger postoperative EOZ may indicate better visual quality, making EOZ an important safety parameter for keratorefractive surgeries. As SMILE has gained wider application globally, the EOZ following SMILE has also been increasingly studied in the field of refractive surgery. This review provides an update on topics related to the EOZ after SMILE, including its measurement and influencing factors, aiming to benefit the personalization of the surgical algorithm and ultimately improve the visual quality after the SMILE procedure.
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Funding
National Natural Science Foundation of China for Young Scholars (Grant No. 82000929); Shanghai Sailing Program (Grant No. 20YF1405000); National Natural Science Foundation of China (82371096); joint research project of new frontier technology in municipal hospitals (SHDC12018103); Clinical Research Plan of SHDC (SHDC2020CR1043B); project of Shanghai Science and Technology (Grant No.20410710100); project of Shanghai Xuhui District Science and Technology (XHLHGG202104); construction of a 3D digital intelligent prevention and control platform for the whole life cycle of highly myopic patients in the Yangtze River Delta (21002411600).
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Conception and design, YH, TH, and XZ; administrative support, XZ; collection and assembly of pictures, YH; data analysis and interpretation, YH and BZ; drafting of the manuscript, YH and TH; critical revision of the manuscript, YH, BZ, TH, and XZ; supervision, TH and XZ. All authors read and approved the final manuscript.
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Huang, Y., Zhan, B., Han, T. et al. Effective optical zone following small incision lenticule extraction: a review. Graefes Arch Clin Exp Ophthalmol 262, 1657–1665 (2024). https://doi.org/10.1007/s00417-023-06263-2
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DOI: https://doi.org/10.1007/s00417-023-06263-2