方法：采用前瞻性病例研究。将2014-04/10在中国医科大学附属盛京医院自愿接受SMILE手术的近视及近视散光患者60例120眼，按照患者术前是否长期配戴角膜接触镜分为两组：角膜接触镜组(60眼)和非角膜接触镜组(60眼)。采用NIDEK confoscan4型角膜共焦显微镜检测两组患者术前及术后1wk，1、6mo时的角膜内皮细胞密度、六角形细胞百分比，并记录数值进行统计学分析。

结果：全部患者手术进行顺利，术中和术后均无危害视力的并发症发生。两组患者的年龄、术前的屈光度数、切除基质透镜的厚度、剩余角膜基质床厚度、术后裸眼视力的差异均无统计学意义(P>0.05)。非角膜接触镜组术前及术后1wk，1、6mo的角膜内皮细胞密度的差异及六角形细胞百分比的差异均无统计学意义(F=0.864、2.488，P=0.460、0.061)。角膜接触镜组术前及术后1wk，1、6mo的角膜内皮细胞密度的差异无统计学意义(F=0.135，P=0.939)，但六角形细胞百分比的差异有统计学意义(F=4.913，P=0.002)； 经LSD-t检验，角膜接触镜组的六角形细胞百分比术后1wk时(30.70±4.08)%较术前(32.23±4.15)%明显降低(P=0.045)； 术后1mo时(33.05±4.28)%恢复至术前水平(P=0.364)； 术后6mo时(34.06±5.11)%与术前比较差异无统计学意义(P=0.091)。两组之间比较，角膜接触镜组的角膜内皮六角形细胞百分比于术前及术后1wk； 1mo时明显低于非角膜接触镜组(t=2.051、1.723、2.092，P=0.037、0.042、0.034)，但术后6mo时与非角膜接触镜组无明显差异(t=0.131，P=0.986)。

结论：在保留剩余角膜基质床厚度≥300μm的条件下，SMILE手术矫正近视和近视散光对角膜内皮细胞密度无影响，仅对角膜内皮六角形细胞百分比造成短暂的影响，其影响程度没有长期配戴角膜接触镜对角膜内皮细胞的影响大，SMILE手术是一种非常安全的角膜屈光手术。

METHODS: In this prospective study, 60 patients(120 eyes)with myopia or myopic astigmatism, who volunteered to receive SMILE from April 2014 to October 2014 in Shengjing Hospital of China Medical University, were divided into two groups: contact lens group(60 eyes)and non-contact lens group(60 eyes). The values of corneal endothelial cell density and the percentages of hexagonal cells, detected by NIDEK confoscan4 corneal confocal microscopy before and 1wk, 1, 6mo after surgery, were recorded and analyzed.

RESULTS: All patients were with successful surgery and there were no complications intraoperative and postoperative. No differences were noted between two groups in terms of average age, refractive error, stromal ablation depth, residual stromal bed depth, and postoperative uncorrected visual acuity(P>0.05). Using the analysis of variance of repeated measurement data, there were no statistically significant differences regarding mean endothelial cell density and percentage of hexagonal cells in pre- and 1wk, 1, 6mo post-SMILE within non-contact lens group(F=0.864, 2.488; P=0.460, 0.061). In the contact lens group, no differences were found regarding mean endothelial cell density in pre- and 1wk, 1, 6mo post-operation(F=0.135, P=0.939), but there were significant differences in the percentage of hexagonal cells(F=4.913, P=0.002). The percentage of hexagonal cells decreased significantly at 1wk post-operation(30.70±4.08)% compared with preoperative(32.23±4.15)%(P=0.045), returned to the preoperative levels at 1mo after surgery(33.05±4.28)%(P=0.364), and showed no difference(P=0.091)at 6mo after surgery(34.06±5.11)% with preoperative data. The percentages of hexagonal cells in the contact lens group were significantly lower in pre- and 1wk, 1mo post-operation than those in the non-contact lens group(t=2.051, 1.723, 2.092; P=0.037, 0.042, 0.034), however, there was no statistically significant difference between two groups at 6mo after surgery(t=0.131, P=0.986).

CONCLUSION: If the required residual stromal thickness limit was ≥300μm, SMILE to correct myopia or myopic astigmatism has no effect on the corneal endothelial cell density, only has short effect on the percentage of corneal hexagonal cells, which is slighter than wearing contact lens. SMILE to correct myopia is safe for corneal endothelium.