角膜板层刀和飞秒激光制瓣准分子激光原位角膜磨镶术后泪液功能及角膜神经再生速度的比较

目的 比较M2机械角膜刀及FEMTO LDV飞秒激光制瓣准分子激光原位角膜磨镶术（LASIK）后泪液功能和角膜神经再生速度，为制定个性化手术方式提供依据。方法 前瞻性病例对照研究。纳入患者40例（80眼），机械角膜板层刀制瓣LASIK（M-LASIK）组和FEMTO LDV飞秒激光制瓣LASIK（F-LASIK）组各20例。观察术后1、3个月泪液功能的3项客观指标即泪膜破裂时间（BUT）、泪液分泌试验（Schirmer I试验）和角膜荧光素染色（FS）评分，并对患者进行角膜共聚焦显微镜检查，对角膜上皮下神经修复速度进行分析。对检查结果进行方差分析、独立样本t检验、Mann-Whitney U检验和Spearman相关分析。结果 术后1个月和3个月F-LASIK组BUT长于M-LASIK组，差异有统计学意义（t=-2.195、-2.174，P<0.05）；2组间Schirmer I试验、FS评分差异无统计学意义。角膜上皮下神经纤维（CSNFs）再生速度评分，术后1个月时F-LASIK组为（1.03±0.63）分，M-LASIK组为（0.83±0.55）分，差异无统计学意义（Z=-1.400，P>0.05）；3个月时分别为（2.31±0.83）分和（1.93±0.80）分，差异有统计学意义（Z=-2.100，P<0.05）。Schirmer I试验和CSNFs再生速度呈正相关（r=0.231，P<0.01），而BUT（r=0.143，P>0.05）和FS评分（r=-0.049，P>0.05）与CSNFs再生速度无相关性。结论 飞秒激光制瓣LASIK术后泪液功能恢复较机械刀制瓣快，角膜瓣切缘处神经修复速度较机械刀制瓣LASIK快。基础泪液分泌量随着角膜上皮下神经修复速度加快而增加。

Tear dynamics and corneal sub-basal nerve fiber regeneration after laser in situ keratomileusis flap made with microkeratome or Femto LDV femotosecond laser

Objective To investigate changes in tear dynamics and corneal sub-basal nerve fiber regeneration after laser in situ keratomileusis （LASIK） surgery with a femtosecond laser and a mechanical microkeratome. Methods In a prospective case-control study， 40 eyes of 20 patients were treated with FEMTO LDV femtosecond laser LASIK surgery （F-LASIK group） or mechanical microkeratome LASIK surgery （M-LASIK group） respectively. Tear film break-up time （BUT）， Schirmer I test with corneal fluorescein staining （FS） and in vivo confocal microscopy of corneal subbasal nerve fibers （CSNFs） were obtained preoperatively and 1 and 3 months after surgery. Images of the CSNFs were analyzed to evaluate nerve regeneration. Data were analyzed using repeated measures ANOVA， an independent samples t test， Mann-Whitney U test and Spearman correlation analysis. Results At 1 and 3 months after operation the average of BUT of F-LASIK group was significantly longer than that of M-LASIK group （t=-2.195， -2.174， P<0.05）. Schirmer I test results and the FS were comparable between the 2 groups. The nerve regeneration score was a little higher in F-LASIK group （1.03±0.63） than that in M-LASIK group （0.83±0.55） at 1 month after surgery， but there was no significant difference （Z=-1.400， P>0.05）. The nerve regeneration score in F-LASIK group （2.31±0.83） was significantly higher than that in M-LASIK group （1.93±0.80） at 3 months after surgery （Z=-2.100， P<0.05）. Significant positive correlations were found between Schirmer I test and the CSNFs regeneration score （r=0.231， P<0.01）， while there was no statistically significant associations between the CSNFs regeneration score and BUT （r=0.143， P>0.05） or FS （r=-0.049， P>0.05）. Conclusion The recovery of tear dynamics and corneal subbasal nerve fibers is faster in FEMTO LDV LASIK than in traditional LASIK. Schirmer I test is increase with the CSNFs regeneration.