Abstract:AIM:To investigate the dry eye symptoms and the stability changes of tear film after correction of myopia by laser-assisted in situ keratomileusis(LASIK)and laser epithelial keratomileusis(LASEK)with the use of 0.1% sodium hyaluronate(HA).
METHODS:A total of 230 myopia patients(460 eyes)were divided into LASIK group and LASEK group from February 2017 to December 2017. Each operation group was randomly assigned to 0.1% HA treatment subgroup and HA-free subgroup. Both subgroups were instructed to apply gatifloxacin(0.3%)and loteprednol(0.5%)after the corneal refractive surgery. The changes of dry eye symptom score, corneal perceptual reaction, corneal fluorescein staining(FL), basic Schirmer Ⅰ test(SⅠt)and tear film break-up time(BUT)were observed in different time points.
RESULTS:There were significant differences in FL, dry eye symptom score and corneal perceptual response between the 0.1% HA treatment group and HA-free group at 1wk, 1, 3 and 6mo after operation both in LASIK and LASEK patients(P<0.05). BUT after operation in each group was significantly deceased at 1wk compared with preoperative level. Other observation time points after surgery of BUT and each postoperative level of SⅠt were still within the normal range although lower than the preoperative levels. The subjective symptoms of dry eyes, tear film stability and corneal surface perception of LASEK patients were better than LASIK patients especially at 1wk, 1 and 3mo after surgery.
CONCLUSION:These two kinds of refractive surgery may cause different degrees of dry eye symptoms. These symptoms in the LASEK group were lighter than that in the LASIK group in the early postoperative period. The early adequate use of preservative-free 0.1% HA could effectively promote the corneal repair and be greatly helpful for postoperative dry eye symptoms.