Zhang Hui, Wang Yan
Clinical College of Ophthalmology, Tianjin Medical University, Tianjin, 300020, China.
Tianjin Eye Hospital, No 4. Gansu Road, Heping District, Tianjin, 300020, China.
Int Ophthalmol. 2018 Dec;38(6):2283-2288. doi: 10.1007/s10792-017-0717-x. Epub 2017 Sep 22.
To investigate the dry eye after small incision lenticule extraction (SMILE) and explore the correlations between changes in the tear film stability, the tear secretion and the corneal surface regularity.
Sixty-two eyes of 22 men and 13 women who underwent SMILE were included in this study. Corneal topography was measured to assess the index of surface variance (ISV) and the index of vertical asymmetry (IVA). Dry eye tests including subjective symptom questionnaire, tear breakup time (TBUT), corneal fluorescein staining and Schirmer's test (ST) were evaluated before and at 1 and 6 months postoperatively.
TBUT was found to be significantly decreased from 9.8 ± 3.4 s preoperatively to 7.4 ± 3.8 s at 1 month and 6.5 ± 3.6 s at 6 months (both P < 0.001). There was a significant decrease in ST at 1 month postoperatively (P = 0.012); however, ST returned to baseline by 6 months (P = 0.522). Both ISV and IVA significantly increased after the surgery (all P < 0.001). In addition, the changes in TBUT were negatively correlated with the increases in ISV and IVA (r = -0.343, P = 0.006 and r = -0.311, P = 0.014, respectively).
Patients undergoing SMILE might develop a short-TBUT type of dry eye. Corneal surface regularity indices might be helpful in the assessment of tear film stability following SMILE procedure.
研究小切口基质透镜切除术（SMILE）后干眼情况，并探讨泪膜稳定性、泪液分泌及角膜表面规则性变化之间的相关性。
本研究纳入了22名男性和13名女性接受SMILE手术的62只眼。测量角膜地形图以评估表面方差指数（ISV）和垂直不对称指数（IVA）。术前及术后1个月和6个月评估干眼测试，包括主观症状问卷、泪膜破裂时间（TBUT）、角膜荧光素染色和泪液分泌试验（ST）。
发现TBUT从术前的9.8±3.4秒显著降低至术后1个月的7.4±3.8秒和6个月的6.5±3.6秒（均P<0.001）。术后1个月ST显著降低（P=0.012）；然而，ST在6个月时恢复至基线水平（P=0.522）。术后ISV和IVA均显著增加（均P<0.001）。此外，TBUT的变化与ISV和IVA的增加呈负相关（r=-0.343，P=0.006；r=-0.311，P=0.014）。
接受SMILE手术的患者可能会出现TBUT缩短型干眼。角膜表面规则性指标可能有助于评估SMILE手术后的泪膜稳定性。
