The aim of this study is to compare higher-order aberrations(HOA)and objective visual quality at 1 year after tomography-guided femtosecond assisted laser in situ keratomileusis (FS-LASIK) versus wavefront-optimized FS-LASIK for the treatment of myopic astigmatism.

98 patients(196 eyes) with myopic astigmatism who underwent FS-LASIK in Shijiazhuang People′s Hospital from January 2022 to December 2023.There were 65 males(130 eyes)and 33 females(66 eyes)with the average age of 20(18.00, 25.25) years(ranging from 18 to 41 years). Patients were divided into the tomography-guided group and the wavefront-optimized group. Uncorrected distance visual acuity, spherical error, cylindrical error, spherical equivalent, keratometry, total HOA, total coma, total trefoil, total spherical aberration, objective scattering index (OSI), modulation transfer function cutoff (MTF cutoff), and Strehl ratio (SR) were evaluated preoperatively and at 3, 6, and 12 months postoperatively. Normally distributed continuous variables were presented as ±s and were compared using t-tests; non-normally distributed variables were presented by median with interquartile range M(Q1, Q3) and were compared using nonparametric tests. Longitudinal changes across time points were assessed using two-way repeated-measures analysis of variance. Considering the non-independence of bilateral-eye data, baseline intergroup and intragroup comparisons were performed using a generalized linear mixed model.

A total of 98 patients (196 eyes) were included, with 54 patients (108 eyes) in the tomography-guided group and 44 patients (88 eyes) in the wavefront-optimized group. In the tomography-guided group, the age, spherical error, cylindrical error, spherical equivalent, flat keratometry, and steep keratometry were 20 (18, 25) years, (5.06±1.54) D, (1.07±0.79) D, (5.60±1.68) D, (42.7±1.16) D, and (44.2±1.18) D, respectively. The corresponding values in the wavefront-optimized group were 20 (18, 28.5) years, (5.04±1.51) D, (1.08±0.69) D, (5.58±1.58) D, (42.6±1.24) D, and (44.1±1.23) D. There were no statistically significant differences between the two groups in baseline characteristics (Z=1.691; F=0.045, 0.052, 0.023, 2.833, 0.029; P>0.05). The logarithm of the minimum angle of resolution(logMAR) of uncorrected distance visual acuity in the tomography-guided and wavefront-optimized groups was 0.9 (0.80, 1.07) logMAR and 1.0 (0.80, 1.00) logMAR preoperatively, and improved to 0.0 (0.08, 0.00) logMAR and 0.0 (0.06, 0.00) logMAR at 12 months postoperatively, respectively. There were no significant differences between the two groups (Z= 0.766, 0.894; P>0.05), whereas significant improvements were observed within each group (Z= 9.050, 8.209; P<0.05). At 12 months postoperatively, the spherical error, cylindrical error, and spherical equivalent were (0.08±0.38)D, (0.24±0.33)D, and (0.21±0.40)D in the tomography-guided group, and (0.07±0.36)D, (0.25±0.35)D, and (0.05±0.43)D in the wavefront-optimized group, respectively. No significant differences were found between the two groups (t= 1.938, 0.163, 1.658; P>0.05). However, significant improvements were observed within both groups compared with preoperative values (t= 19.561, 6.258, 20.694, 22.841, 6.875, 23.209; P<0.05). In the tomography-guided group, the values for total HOA, total coma, total trefoil, and total spherical aberration preoperatively and at 3, 6, and 12 months were (0.33±0.10), (0.58±0.18), (0.56±0.19), (0.61±0.19), (0.15±0.08), (0.31±0.12), (0.31±0.12), (0.30±0.12), (0.20±0.09), (0.19±0.08), (0.19±0.09), (0.19±0.06), (0.09±0.04), (0.22±0.09), (0.19±0.08), (0.21±0.09), respectively. Corresponding values for the wavefront-optimized group were (0.33±0.12), (0.60±0.21), (0.60±0.22), (0.63±0.23), (0.17±0.07), (0.40±0.16), (0.39±0.22), (0.34±0.13), (0.20±0.08), (0.26±0.07), (0.25±0.08), (0.27±0.09), (0.10±0.04), (0.39±0.12), (0.32±0.09), and (0.31±0.09), respectively. There was statistically significant difference between the groups at postoperative time points in total coma, total trefoil, and total spherical aberration (t=4.241, 3.814, 2.595, 6.236, 5.504, 8.035, 11.914, 9.554, 7.237; P<0.05). In the tomography-guided group, total HOA, total coma, and total spherical aberration showed statistically significant difference over time (F=72.501, 61.390, 53.259; P<0.05). In the wavefront-optimized group, total HOA, total coma, total trefoil, and total spherical aberration all showed statistically significant difference over time (F=165.185, 55.345, 14.853, 174.245; P<0.05). The OSI, MTF cutoff, and SR values in the tomography-guided group preoperatively and at 3, 6, and 12 months postoperatively were 0.66(0.54, 0.80), 0.68(0.54, 0.82), 0.69(0.53, 0.82), 0.68(0.54, 0.82), (35.86±0.51), (36.40±2.05), (36.63±2.41), (36.63±2.61), (0.202±0.06), (0.214±0.04), (0.214±0.05), (0.212±0.04), respectively. Corresponding values for the wavefront-optimized group were 0.67(0.58, 0.77), 0.66(0.59, 0.76), 0.66(0.59, 0.75), 0.66(0.58, 0.76), (35.70±1.90), (35.65±1.88), (35.60±1.88), (35.71±2.03), (0.201±0.09), (0.201±0.03), (0.203±0.03), and (0.196±0.03), respectively. There was statistically significant difference in MTF cutoff at all postoperative time points (t=2.661, 3.278, 2.611; P<0.05)and in SR at 3 and 12 months postoperatively (t=2.304, 2.611; P<0.05). In the tomography-guided group, MTF cutoff and SR showed statistically significant variations over time(F=14.836, 5.766; P<0.05). In the wavefront-optimized group, OSI, MTF cutoff, and SR showed no statistically significant variations over time (F=0.124, 1.920, 2.581; P>0.05).

Tomography-guided FS-LASIK yields lower postoperative total coma, total trefoil and total spherical aberration values, along with higher MTF cutoff and SR, compared with wavefront-optimized FS-LASIK, thereby providing superior visual quality for patients with myopic astigmatism.