Abstract
Purpose :
To assess the long-term (1-year) effect of myopic femtosecond laser-assisted in situ keratomileusis (FS-LASIK) on clinical characteristics and tear film biomarkers.
Methods :
Eighty eyes from 80 patients who underwent FS-LASIK were evaluated. Ocular surface symptoms and signs were evaluated using specific questionnaires and tests. The corneal nerves and dendritic cells (DCs) were examined using in vivo confocal microscopy. Corneal sensitivity was evaluated using a Cochet-Bonnet esthesiometer. Tear inflammatory cytokines and neuropeptides were evaluated using Luminex immunoassay. These examinations were performed preoperatively and at 1, 3, 6, and 12 months postoperatively.
Results :
Seventy-three participants completed all the follow-ups. Following FS-LASIK, ocular symptoms and signs (except Schirmer I test) worsened at 1 month but corneal and conjunctival stainings improved by 3 months. The numbers of DC and activated DC increased at the 3-month postoperative visit and recovered to preoperative levels by the 6-month visit. Ocular symptoms and corneal sensitivity recovered to preoperative levels at the 12-month visit. Tear break-up time and corneal nerve morphology were not recovered to preoperative status at the 12-month visit. Interleukin (IL)-1β, IL-17A, tumor necrosis factor-α, and substance P (SP) tear levels significantly increased at all postoperative visits compared to preoperative levels. Corneal staining scores positively correlated with tear IL-1β and IL-17A levels, while corneal nerve morphology positively correlated with corneal sensitivity and negatively correlated with SP levels.
Conclusions :
Although most clinical variables improved at 12 months postoperatively, some tear inflammatory cytokines and SP remain altered beyond 12 months, indicates that ocular homeostasis is not completely recovered.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.