COMPARATIVE ANALYSIS OF INFLAMMATORY AND ANTI-INFLAMMATORY CYTOKINE DYNAMICS IN TEAR FILM FOLLOWING DEEP ANTERIOR LAMELLAR KERATOPLASTY

Abstract

Keratoconus is a progressive corneal ectatic disorder leading to irregular astigmatism and visual impairment. Deep anterior lamellar keratoplasty (DALK) is the preferred surgical option for advanced cases, as it preserves the host endothelium while replacing diseased stromal tissue. However, postoperative inflammatory responses play a critical role in graft survival, wound healing, and visual outcomes. Evaluation of cytokine dynamics may provide objective insight into the biological impact of different surgical techniques.

Purpose – to conduct a comprehensive analysis of the dynamics of inflammatory and anti-inflammatory cytokines in the tear film after DALK in patients with keratoconus.

Material and methods
This prospective, comparative, non-randomized clinical study included 50 patients with progressive keratoconus who underwent either conventional DALK (n=30) or femtosecond laser-assisted deep anterior lamellar keratoplasty (n=20). A control group of 30 healthy volunteers was enrolled. Tear film samples were collected preoperatively and at 1, 3, 6, and 12 months postoperatively. Interleukin-6 (IL-6) and interleukin-10 (IL-10) concentrations were measured using enzyme- linked immunosorbent assay. The IL-6/IL-10 ratio was calculated as an indicator of inflammatory balance.

Results
Both surgical techniques were associated with postoperative elevation of inflammatory markers; however, femtosecond laser-assisted surgery demonstrated significantly lower IL-6 levels and higher IL-10 concentrations at all postoperative time points. The IL-6/IL-10 ratio remained significantly more favorable in the femtosecond laser-assisted group, indicating a reduced inflammatory response. A ratio greater than 5.0 at one month predicted unfavorable outcomes.

Conclusion
Femtosecond laser-assisted deep anterior lamellar keratoplasty induces a more favorable postoperative inflammatory profile compared to conventional surgery, supporting its biological and clinical advantages in keratoconus management.