[Efficacy of small incision lenticule extraction combined with femtosecond laser-assisted in situ keratomileusis for optimized monovision correction in myopia patients with presbyopia].

ABSTRACT

Objective: To evaluate the efficacy of optimized monovision correction using small incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK) in myopic patients with presbyopia and to assess the corneal epithelial remodeling following these procedures. Methods: A prospective study was conducted. Thirty-two patients (64 eyes) with myopia and presbyopia who underwent surgical correction at Chongqing Bai Ji Eye Clinic from August 2021 to April 2023 were continuously included. There were 9 males and 23 females, with an average age of (44.25±2.96) years. The dominant eyes (32 eyes) underwent SMILE, while the non-dominant eyes (32 eyes) underwent FS-LASIK with mild myopia and partial negative spherical aberration induction. Data on visual acuity and refraction were collected preoperatively and at 1 week, 1 month, 3 months, and 6 months postoperatively. Total ocular aberrations were measured using the iProfiler Plus, and the corneal epithelial thickness in different regions was assessed using anterior segment optical coherence tomography. Safety and efficacy indices were calculated based on visual acuity, the defocus and contrast sensitivity were measured using the Binoptometer 4P binocular vision tester, and a patient satisfaction survey was performed. Results: At 1 week postoperatively, the uncorrected distance visual acuity (UDVA) of dominant eyes significantly improved compared to preoperative values. At 3 months postoperatively, the uncorrected near visual acuity (UNVA) of non-dominant eyes showed significant improvement (P<0.05), 96.9% (31 eyes) of the dominant eyes achieved UDVA of 1.0 or better, and 93.8% (30 eyes) of the non-dominant eyes achieved UNVA of 0.8 or better. The safety index for distance vision was 1.15±0.09, and the efficacy index was 1.15±0.11. At 1 week, 1 month, 3 months, and 6 months postoperatively, the proportion of dominant eyes with a spherical equivalent (SE) deviation within ±0.50 D of the target was 90.6% (29 eyes), 90.6% (29 eyes), 93.8% (30 eyes), and 96.2% (31 eyes), respectively; for non-dominant eyes, the corresponding proportions were 81.3% (26 eyes), 87.5% (28 eyes), 93.8% (30 eyes), and 96.2% (31 eyes). The postoperative spherical aberration was (0.11±0.03) µm for dominant eyes and (-0.01±0.04) µm for non-dominant eyes, showing a statistically significant difference (P<0.05). At 1 week and 1 month postoperatively, the central corneal epithelial thickness of non-dominant eyes was significantly higher than that of dominant eyes [(71.34±21.69) µm vs. (51.97±6.33) µm at 1 week, and (61.34±15.85) µm vs. (52.72±6.32) µm at 1 month; P<0.05]. Patient satisfaction was high, with 96.9% (31 patients) rating their satisfaction as "satisfactory" or higher. Conclusions: The combined use of SMILE and FS-LASIK for optimized monovision correction in myopic patients with presbyopia is both safe and effective, achieving high postoperative satisfaction. The SMILE procedure reduces the extent of corneal epithelial remodeling compared to FS-LASIK.