Abstract:AIM: To explore the efficacy of 0.05% cyclosporine A(CsA)eye drops for preventing dry eye after femtosecond laser-assisted laser in situ keratomileusis(FS-LASIK).
METHODS: In this prospective randomized controlled study, a total of 80 patients(80 eyes)who underwent FS-LASIK surgery at the Affiliated Hospital of Xuzhou Medical University from January 2025 to September 2025 were enrolled, and only the data from the right eye were included for analysis. Before surgery, these patients were randomly assigned in a 1:1 ratio using a computer-generated sequence to a control group or an experimental group. All patients received standard postoperative treatment starting from postoperative day 1, including 0.5% levofloxacin eye drops, 0.1% fluorometholone eye drops, and 0.1% sodium hyaluronate eye drops(four times daily for 3 mo). The experimental group additionally received 0.05% cyclosporine A eye drops in addition to the standard treatment. The following parameters were compared between the two groups preoperatively and at 1 and 3 mo postoperatively: ocular surface disease index(OSDI)score, numerical rating scale(NRS)for ocular symptoms, lipid layer thickness(LLT), meibomian gland dropout score, Schirmer's Ⅰ test(SⅠt), corneal fluorescein staining(CFS)score, non-invasive tear breakup time(NIBUT), and tear meniscus height(TMH). Confocal microscopy was employed to evaluate corneal nerve parameters, including corneal nerve fiber density(CNFD), corneal nerve branch density(CNBD), corneal nerve fiber length(CNFL), and corneal total branch density(CTBD), and to count Langerhans cell density(DCD). In addition, levels of interferon-gamma(IFN-γ), interleukin(IL)-1β, IL-6, IL-10, and matrix metalloproteinase-9(MMP-9)in the tear were measured using liquid chip technology.
RESULTS: A total of 72 patients completed the final follow-up, including 37 patients(15 males, 22 females, mean age 24.05±4.00 y)in the experimental group, 35 patients(16 males, 19 females, mean age 23.77±3.71 y)in the control group. At 1 and 3 mo postoperatively, the experimental group showed significantly lower OSDI scores, NRS eye pain scores, and CFS scores(all P<0.01), and significantly higher NIBUT and TMH values, compared with the control group. Confocal microscopy revealed that DCD was significantly lower in the experimental group at 1 and 3 mo postoperatively, whereas CNFD, CNBD, CNFL, and CTBD were significantly higher at 3 mo postoperatively(all P<0.01). Analysis of tear inflammatory cytokines showed that the levels of IFN-γ, IL-1β, IL-6, and MMP-9 were significantly lower in the experimental group at 1 and 3 mo postoperatively compared with the control group(all P<0.01). Spearman correlation analysis revealed that OSDI and NRS scores were negatively correlated with NIBUT, corneal nerve parameters(CNFD, CNBD, CNFL, CTBD), and corneal sensitivity(all P<0.01), and positively correlated with CFS scores, tear inflammatory cytokines(IFN-γ, IL-10, IL-1β, IL-6, and MMP-9), and DCD(all P<0.01). Tear inflammatory cytokines were negatively correlated with corneal nerve parameters, NIBUT, and corneal sensitivity(all P<0.01), and positively correlated with CFS scores and DCD(all P<0.01). No significant correlations were observed among the remaining parameters(P>0.05).
CONCLUSION: Prophylactic use of 0.05% cyclosporine A eye drops significantly improves dry eye symptoms and signs, suppresses ocular surface inflammation, and promotes the restoration of tear film stability in patients after FS-LASIK. Through its dual anti-inflammatory and neuroregenerative effects, cyclosporine A constitutes an effective adjuvant therapy for reestablishing ocular surface microenvironment homeostasis after refractive surgery.
