To evaluate the effect of topical N-acetylcysteine (NAC) on interleukin 1-alpha (IL-1α) levels in tear fluid after myopic laser subepithelial keratectomy (LASEK) and its possible role in modulating corneal wound healing.
Methods
Twenty-six eyes of 13 patients who underwent myopic LASEK were divided into 2 groups. Group 1 (n=10 eyes) was used as a control group. All patients received topical lomefloxacin and dexamethasone postoperatively. Additionally, patients in Group 2 received topical NAC for 1 month postoperatively. Tear fluid samples were collected with microcapillary tubes preoperatively, on the first and on the fifth postoperative day, and the release of IL-1α in tear fluid was calculated. Haze grading and confocal microscopic examination were performed at 1 and 3 months postoperatively.
Results
The mean IL-1-α release values were 0.285±0.159 pg/min in Group 1 and 0.235±0.142 pg/min in Group 2 preoperatively. In Group 1, the values were 0.243±0.155 pg/min on day 1 and 0.164±0.125 pg/min on day 5. In Group 2, the mean IL-1α release values were 0.220±0.200 pg/min on day 1 and 0.080±0.079 pg/min on day 5. The difference between the groups was significant only for day 5 (p<0.05). Mean corneal haze score and grey scale value in confocal microscopy were significantly higher (p<0.05) in Group 1 at 1 month. However, at 3 months there was no difference between groups (p>0.05).
Conclusions
NAC seems to have an additive effect to steroids in suppressing IL-1α levels in tear fluid and may be clinically advantageous in modulating corneal wound healing during the early postoperative period after LASEK.
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