Ten-year observation of corneal densitometry and associated factors following small incision lenticule extraction
Authors:   Eye Institute and Department of Ophthalmology, Eye &amp; ENT Hospital, Fudan University, Shanghai 200031, China; NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai 200031, China; Shanghai Research Center of Ophthalmology and Optometry, Shanghai 200031, China, Han Xiao-Song , Chen Zhuo-Yi ,   Eye Institute and Department of Ophthalmology, Eye &amp; ENT Hospital, Fudan University, Shanghai 200031, China; NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai 200031, China; Shanghai Research Center of Ophthalmology and Optometry, Shanghai 200031, China, Yao Pei-Jun ,   Eye Institute and Department of Ophthalmology, Eye &amp; ENT Hospital, Fudan University, Shanghai 200031, China; NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai 200031, China; Shanghai Research Center of Ophthalmology and Optometry, Shanghai 200031, China, Yang Dong-Mei ,   Eye Institute and Department of Ophthalmology, Eye &amp; ENT Hospital, Fudan University, Shanghai 200031, China; NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai 200031, China; Shanghai Research Center of Ophthalmology and Optometry, Shanghai 200031, China, Zhao Jing ,   Eye Institute and Department of Ophthalmology, Eye &amp; ENT Hospital, Fudan University, Shanghai 200031, China; NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai 200031, China; Shanghai Research Center of Ophthalmology and Optometry, Shanghai 200031, China, Zhou Xing-Tao ,   Eye Institute and Department of Ophthalmology, Eye &amp; ENT Hospital, Fudan University, Shanghai 200031, China; NHC Key Laboratory of Myopia (Fudan University); Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai 200031, China; Shanghai Research Center of Ophthalmology and Optometry, Shanghai 200031, China
Published: February 2024

AIM: To investigate the long-term changes of corneal densitometry (CD) and its contributing elements after small incision lenticule extraction (SMILE).
METHODS: Totally 31 eyes of 31 patients with mean spherical equivalent of -6.46±1.50 D and mean age 28.23±7.38y were enrolled. Full-scale examinations were conducted on all patients preoperatively and during follow-up. Visual acuity, manifest refraction, axial length, corneal thickness, corneal higher-order aberrations, and CD were evaluated.
RESULTS: All surgeries were completed successfully without complications or adverse events. Ten-year safety index was 1.17±0.20 and efficacy 1.04±0.28. CD value of 0–6 mm zones in central layer was statistically significantly lower 10y postoperatively, compared with preoperative values (0–2 mmΔ=-1.62, 2–6 mmΔ=-1.24, P<0.01). There were no correlations between CD values and factors evaluated.
CONCLUSION: SMILE is a safe and efficient procedure for myopia on a long-term basis. CD values get lower 10y postoperatively, whose mechanism is to be further discussed.