Changes of Subjective Symptoms and Tear Film Biomarkers Following Lenticule Extraction

Abstract

Purpose: To investigate the influence of lenticule extraction on subjective symptoms and objective biomarkers of dry eye and to clarify relationships between markers and find indicators for subjective symptoms after lenticule extraction. Methods: Right eyes of myopic patients undergoing lenticule extraction surgery (n = 35) were examined preoperatively and 5 and 90 days postoperatively using established clinical dry eye examination methods (tear film break-up time [BUT], Schirmer test, lissamine green and fluorescein staining, and Ocular Surface Disease Index (OSDI) questionnaire). A patient subset was also examined after 1 year (n = 14). Tear samples were eluted from Schirmer strips and then measured with enzyme-linked immunosorbent assays (calcitonin gene-related peptide (CGRP), interleukin-1β, IL-6, IL-8, matrix metallopeptidase 9 [MMP-9], nerve growth factor, and tumor necrosis factor-α). Postoperatively, unpreserved ofloxacin and dexamethasone eye drops were given (four times a day for 10 days). Results: BUT decreased at days 5 ( P = .023) and 90 ( P = .025). Lissamine green staining increased at day 90 ( P = .036). OSDI values increased at day 5 (total values, vision-related function, ocular symptoms, all P < .001, but not environmental triggers) and at day 90 (vision-related function, P = .017). A downregulation of CGRP ( P = .006) and MMP-9 levels ( P = .042) was observed on day 5 compared to day 90. Conclusions: Due to incongruity of patient symptoms, clinical signs, and tear protein changes, no predictive indicator was found, but some patients reported increased discomfort. Changes after lenticule extraction are not exclusively due to dry eye. [ J Refract Surg . 2023;39(9):597–604.]