Zhang Lin, Wang Yan, Zhao Wei, Cheng Wenbo, Cui Tong
Clinical College of Ophthalmology, Tianjin Medical University, Tianjin, China.
Tianjin Eye Hospital and Eye Institute, Tianjin Key Lab of Ophthalmology and Visual Science, Clinical College of Ophthalmology, Tianjin Medical University, No 4. Gansu Road, Heping District, Tianjin, 300020, China.
Int Ophthalmol. 2019 Aug;39(8):1827-1836. doi: 10.1007/s10792-018-1010-3. Epub 2018 Aug 31.
To evaluate the three-dimensional corneal spatial profiles following small incision lenticule extraction (SMILE) based on corneal asphericity, thickness, and volume.
Eighty-three eyes in 83 patients who underwent SMILE were examined before and 1 and 6 months after surgery. The asphericity of the anterior and posterior corneal surfaces was analyzed. Corneal volume (CV) was measured in corneal regions measuring 3.0 mm, 5.0 mm, and 7.0 mm in diameter. Mean corneal thickness (CT) values were acquired at the apex (0.0 mm) and in four concentric radial zones from the apex (with diameters of 2.0, 4.0, 6.0, and 8.0 mm).
The mean anterior Q value increased from - 0.32 preoperatively to 0.67 at 1 month and 0.62 at 6 months postoperatively. The mean posterior Q value decreased from - 0.30 preoperatively to - 0.26 at 1 month and to - 0.25 at 6 months postoperatively. The CV increased by 0.05 ± 0.06 mm (1.40%), 0.06 ± 0.11 mm (0.83%), and 0.09 ± 0.17 mm (0.73%) along the radial zones with respective diameters of 3.0 mm, 5.0 mm, and 7.0 mm. The CT increased by 6.02 ± 6.48 µm (1.36%) at the apex and then decreased with increasing distance from the center, i.e., to 5.52 ± 6.31 µm (1.20%) at 2.0 mm, 4.72 ± 6.55 µm (0.92%) at 4.0 mm, 4.47 ± 7.86 µm (0.75%) at 6.0 mm, and 4.86 ± 10.31 µm (0.70%) at 8.0 mm. No correlations were observed between changes in CV and CT and refractive fluctuation between 1 month and 6 months postoperatively.
The corneal profile displayed a less oblate shift on the anterior surface; however, the posterior surface showed a slight backward shift during the postoperative period. The CV and CT steadily increased after surgery and mainly within the operative zones. Refraction remained stable postoperatively and was not affected by the corneal remodeling.
基于角膜非球面性、厚度和体积，评估小切口透镜切除术（SMILE）后的三维角膜空间轮廓。
对83例行SMILE手术的患者的83只眼在术前、术后1个月和6个月进行检查。分析角膜前表面和后表面的非球面性。在直径为3.0mm、5.0mm和7.0mm的角膜区域测量角膜体积（CV）。在角膜顶点（0.0mm）以及距顶点四个同心径向区域（直径分别为2.0、4.0、6.0和8.0mm）获取平均角膜厚度（CT）值。
术前平均前表面Q值为-0.32，术后1个月增加至0.67，术后6个月为0.62。术前平均后表面Q值为-0.30，术后1个月降至-0.26，术后6个月降至-0.25。沿直径分别为3.0mm、5.0mm和7.0mm的径向区域，CV分别增加了0.05±0.06mm（1.40%）、0.06±0.11mm（0.83%）和0.09±0.17mm（0.73%）。角膜顶点处CT增加了6.02±6.48μm（1.36%），然后随着距中心距离增加而减小，即2.0mm处为5.52±6.31μm（1.20%），4.0mm处为4.72±6.55μm（0.92%），6.0mm处为4.47±7.86μm（0.75%），8.0mm处为4.86±10.31μm（0.70%）。术后1个月至6个月期间，未观察到CV和CT的变化与屈光波动之间存在相关性。
角膜轮廓在前表面显示出较少的扁圆移位；然而，术后期间后表面显示出轻微的后移。术后CV和CT稳步增加，且主要在手术区域内。术后屈光保持稳定，不受角膜重塑影响。
