Sarkar Samrat, Devi Preetirupa, Vaddavalli Pravin Krishna, Reddy Jagadesh C, Bharadwaj Shrikant R
The Cornea Institute, L V Prasad Eye Institute, Hyderabad, Telangana, India.
Optom Vis Sci. 2022 Feb 1;99(2):137-149. doi: 10.1097/OPX.0000000000001850.
Psychophysical estimates of spatial and depth vision have been shown to be better after bilateral ReLEx small-incision lenticule extraction (SMILE) refractive surgery for myopia, relative to photorefractive keratectomy (PRK) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK). The present study provides the optical basis for these findings using computational image quality analysis.
This study aimed to compare longitudinal changes in higher-order wavefront aberrations and image quality before and after bilateral PRK, FS-LASIK, and SMILE refractive procedures for correcting myopia.
Wavefront aberrations and image quality of both the eyes of 106 subjects (n = 40 for FS-LASIK and SMILE and n = 26 for PRK) were determined pre-operatively and at 1-week, 1-month, 3-month, and 6-month post-operative intervals using computational through-focus analysis for a 6-mm pupil diameter. Image quality was quantified in terms of its peak value and its interocular difference, residual defocus that was needed to achieve peak image quality (best focus), and the depth of focus.
The increase in root mean squared deviations of higher-order aberrations post-operatively was lesser after SMILE (1-month visit median [25th to 75th interquartile range], 0.34 μm (0.28 to 0.39 μm]) than after PRK (0.80 μm [0.74 to 0.87 μm]) and FS-LASIK (0.74 μm [0.59 to 0.83 μm]; P ≤ .001), all relative to pre-operative values (0.20 μm [0.15 to 0.30 μm]). The peak image quality dropped and its interocular difference increased, best focus shifted myopically by 0.5 to 0.75 D, and depth of focus widened significantly after PRK and FS-LASIK surgeries, all relative to pre-operative values (P < .001). All these changes were negligible but statistically significant in a minority of instances after SMILE surgery (P ≥ .01).
Although all three refractive surgeries correct myopia, the image quality and its similarity between eyes are better and closer to pre-operative values after SMILE, compared with FS-LASIK and PRK. These results can be explained from the underlying increase in higher-order wavefront aberrations experienced by the eye post-operatively.
与准分子激光角膜切削术（PRK）和飞秒激光原位角膜磨镶术（FS-LASIK）相比，双侧ReLEx小切口透镜切除术（SMILE）治疗近视后，空间和深度视觉的心理物理学估计结果更好。本研究使用计算图像质量分析为这些发现提供了光学基础。
本研究旨在比较双侧PRK、FS-LASIK和SMILE屈光手术矫正近视前后高阶波前像差和图像质量的纵向变化。
使用计算全聚焦分析，对106名受试者（FS-LASIK和SMILE组各40例，PRK组26例）双眼在术前以及术后1周、1个月、3个月和6个月的波前像差和图像质量进行测定，瞳孔直径为6mm。图像质量通过其峰值、双眼差异、达到峰值图像质量（最佳聚焦）所需的残余散焦以及焦深进行量化。
与术前值（0.20μm[0.15至0.30μm]）相比，SMILE术后高阶像差的均方根偏差增加量（1个月随访时中位数[第25至75四分位数间距]，0.34μm[0.28至0.39μm]）小于PRK术后（0.80μm[0.74至0.87μm]）和FS-LASIK术后（0.74μm[0.59至0.83μm]；P≤0.001）。PRK和FS-LASIK手术后，图像质量峰值下降，双眼差异增加，最佳聚焦近视性偏移0.5至0.75D，焦深显著变宽，所有这些均相对于术前值（P<0.001）。SMILE手术后，所有这些变化在少数情况下可忽略不计，但具有统计学意义（P≥0.01）。
尽管三种屈光手术均能矫正近视，但与FS-LASIK和PRK相比，SMILE术后的图像质量及其双眼之间的相似性更好，且更接近术前值。这些结果可以从术后眼睛高阶波前像差的潜在增加来解释。
