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Seven-year corneal densitometry changes after small incision lenticule extraction and femtosecond laser-assisted in situ keratomileusis

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Abstract

This study aims to investigate the 7-year changes in corneal densitometry (CD) after small incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK). Forty-two eyes undergoing SMILE and thirty-one undergoing FS-LASIK were included in this retrospective study. CD was measured preoperatively and at 3 and 7 years postoperatively. Three concentric radial zones (0–2, 2–6, and 6–10 mm) of three different corneal depths (anterior 120 μm, posterior 60 μm, and central layer) were analyzed. In all three zones of the three corneal layers, no significant difference in CD was found between the two groups preoperatively and at 3 and 7 years postoperatively (all P > 0.05). All CD values in the three zones of the anterior and central layers significantly declined at 3 years postoperatively (all P < 0.001), and then increased at 7 years postoperatively compared to corresponding 3-year values (all P < 0.01). In the posterior layer, CD values in the 0–2-mm and 2–6-mm zones decreased at 3 years postoperatively (all P < 0.01) and continued to decrease at 7 years postoperatively (all P < 0.01). Similar CD trends were observed after SMILE and FS-LASIK. Posterior layer CD showed a decrease throughout the study period. In the anterior and central layers, CD values decreased and then increased at 7 years postoperatively. The transparency changes might have been due to age-related three-dimensional growth of collagen fibers and wound-healing reactions.

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Funding

This study was supported in part by the National Natural Science Foundation of China for Young Scholars (Grant No. 82000929), the Shanghai Sailing Program (Grant No. 20YF1405000), National Natural Science Foundation of China (Grant No. 81770955), Project of Shanghai Science and Technology (Grant No.20410710100), Clinical Research Plan of SHDC (SHDC2020CR1043B), Project of Shanghai Xuhui District Science and Technology (2020-015), Project of Shanghai Xuhui District Science and Technology(XHLHGG202104), Shanghai Engineering Research Center of Laser and Autostereoscopic 3D for Vision Care (20DZ2255000), 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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Author notes

  1. Tian Han and Luoli Zhang contributed equally and are considered co-first authors.

Authors and Affiliations

  1. Department of Ophthalmology, Eye and ENT Hospital of Fudan University, Shanghai, China

    Tian Han, Luoli Zhang, Yangyi Huang, Yang Shen, Xingtao Zhou & Ye Xu

  2. NHC Key Laboratory of Myopia (Fudan University), Shanghai, China

    Tian Han, Luoli Zhang, Yangyi Huang, Yang Shen, Xingtao Zhou & Ye Xu

  3. Research Center of Ophthalmology and Optometry Shanghai, Shanghai, China

    Tian Han, Luoli Zhang, Yangyi Huang, Yang Shen, Xingtao Zhou & Ye Xu

  4. Shanghai Engineering Research Center of Laser and Autostereoscopic 3D for Vision Care (20DZ2255000), Shanghai, China

    Tian Han, Luoli Zhang, Yangyi Huang, Yang Shen, Xingtao Zhou & Ye Xu

Authors
  1. Tian Han
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  2. Luoli Zhang
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  3. Yangyi Huang
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  4. Yang Shen
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  5. Xingtao Zhou
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Contributions

TH, XTZ, and YX were involved in the conception and design of the study. Material preparation and data collection were performed by TH, YYH, and YS. Data analysis was performed by LLZ. The first draft of the manuscript was written by TH and LLZ. Critical revision of the manuscript was performed by XTZ and YX. All authors read and approved the final manuscript.

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Correspondence to Xingtao Zhou or Ye Xu.

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Han, T., Zhang, L., Huang, Y. et al. Seven-year corneal densitometry changes after small incision lenticule extraction and femtosecond laser-assisted in situ keratomileusis. Lasers Med Sci 38, 183 (2023). https://doi.org/10.1007/s10103-023-03850-x

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  • DOI: https://doi.org/10.1007/s10103-023-03850-x

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