The aim of this study was to evaluate optical and visual quality after implantable collamer lens (ICL) implantation for high myopia and astigmatism correction.

Thirty-two subjects (49 eyes) with high myopia and astigmatism correction, who accepted implantable collamer lens implantation at Hunan Provincial People's Hospital from January to December 2017 were enrolled. The time of surgery was 26.38±7.39 years with the range from 21 years-old to 42 years-old. The mean preoperative range of spherical refraction was -6.00 to -11.00 D, cylinder refraction was -2.50 to 0 D, and spherical equivalent was (-9.39±1.80) D. All subjects underwent ICL implantation. Uncorrected visual acuity, best corrected visual acuity, spherical equivalent, objective scatter index (OSI), and modulation transfer function (MTF) cut off frequency, at preoperative, postoperative 1 week, 1 month, 3 months, and 6months, were recorded. The postoperative uncorrected visual acuity and spherical equivalent were used as the categorical variables which were expressed as number and percentage. The Chi-square test was used for statistical analysis. OSI values and MTF cut off values were expressed as mean±standard deviation. One-way analysis of variance was used to compare preoperative and postoperative time points. When the difference is statistically significant, pair wise comparison was perfomred by Least-Significant Difference t test.

Among of 49 eyes, uncorrected visual acuityat with 1.0 or better was 95.92% (47 eyes), those of at 1.2 or better was 66.35% (33 eyes) at postoperative 6 months. There were 42 eyes (85.71%) gained 1 or more lines; no patients lost lines of best corrected visual acuity. The mean spherical equivalent was (0.30±0.20) D at postoperative 6 months. The OSI value was(1.16±0.77), (1.04±0.60), (0.99±0.60), (0.86±0.38), and (0.85±0.37) at preoperative, postoperative 1 week, 1 month, 3 months, and 6 months, respectively. There were significant differences between each time point (F=2.78, P<0.05) using one-way analysis of variance. Further comparisons showed that the OSI values at each postoperative time point were all lower than that of pre-operation, but there was not shown statistically between postoperative 1 week, postoperative 1 month and before operation (t=1.36, 0.95; P>0.05). While there were significant differences between postoperative 3 months, postoperative 6 months and pre-operation (t=5.79, 6.05; P<0.05). There were no significant differences between postoperative time points (F=0.66, P>0.05). The MTF cut off was (34.04±9.71), (35.88±9.02), (37.15±9.89), (37.11±6.61), and (37.08±3.31) at preoperative, postoperative 1 week, 1 month, 3 months, and 6 months, respectively. There were significant differences between each time point (F=2.14, P<0.05) by one-way analysis of variance. The MTF cut off at postoperative time points were all higher than pre-operation, but there not shown statistically between postoperative 1 week and pre-operation (t=0.13, P>0.05). While there were significant differences between postoperative1 month, postoperative 3 months, postoperative 6 months and pre-operation (t=26.36, 23.85, 17.88; P<0.05). The MTF cut off at postoperative 1 month was higher than postoperative 1 week, however, there was no significant difference (t=0.66, P>0.05). There were no significant differences between postoperative 1 month, postoperative 3 months, and postoperative 6 months (F=0.00, P>0.05).

ICL was good, safety and effectiveness in high myopia and astigmatism correction. The optical and visual quality was significantly improved after operation, and got a stable state at postoperative 1 month.