Evaluation of the Visual Quality in Myopic and Astigmatic Patients Treated with Corneal Topography-Guided FS-LASIK

Objective: To observe and evaluate the changes in visual quality after corneal topography-guided FS-LASIK for myopia and astigmatism. Methods: This was a prospective study. Forty patients (68 eyes) with myopia or myopic astigmatism were selected from June to October 2017 in the Optometry Center, Hunan People's Hospital and divided into a middle-high astigmatism group (32 eyes, astigmatism >1.0 D) and a low astigmatism group (36 eyes, astigmatism ≤1.0 D). The corneal topography-guided FS-LASIK was used. The preoperative and postoperative 3-month visual acuity (UCVA), best corrected visual acuity (BCVA), refractive error, corneal total higher-order aberrations, corneal spherical aberration, corneal coma, MTF cutoff and objective scattering index (OSI) were recorded. Data were analyzed using t test. Results: The UCVA of 100% of the eyes reached preoperative BCVA at 3 months after surgery. The UCVA (LogMAR) of the patients at 3 months after operation was -0.10±0.07, which was significantly higher than that of preoperative BCVA (LogMAR) -0.02±0.07 (t=8.714, P<0.001). The prevalence of spherical equivalent (SE) within ±0.50 was 94%; the residual astigmatism was 0.40±0.17 D. At 3 months, postoperative coma and OSI decreased compared with preoperative levels, and the MTF cutoff increased compared with preoperative levels. The difference was statistically significant (t=1.757, -2.935, 4.243, P<0.05). The UCVA, coma and MTF of the moderate and high astigmatism group and the low astigmatism group had improved at 3 months after surgery, and there was no significant difference between the two groups. Conclusions: FS-LASIK guided by corneal topography can effectively improve the visual quality of myopic astigmatism patients. Key words: corneal topography guide; femtosecond laser; laser in situ keratomileusis; myopia; astigmatism; visual quality