Interplay Of Tear Cytokine Levels And Confocal Microscopy In Progressive Keratoconus
Published 2026 - 44th Congress of the ESCRS
Reference: FP06.14 | Type: Free paper | DOI: 10.82333/wajq-0048
Authors: Dr Priyam Gupta* 1 , Dr Rashmi Deshmukh 2 , Dr Vivek Singh 3
1Cataract and refractive,L.V. Prasad Eye Institute,Hyderabad,India, 2Cornea and Anterior Segment,L.V. Prasad Eye Institute,Hyderabad,India, 3Research department ,L.V. Prasad Eye Institute,Hyderabad,India
Purpose
Keratoconus (KC) is a bilateral yet asymmetric corneal ectatic disorder characterized by progressive corneal thinning and protrusion. While biomechanical and genetic predispositions are well established, inflammatory mediators are increasingly recognized as contributing factors. Our aim was to analyse IVCM changes in progressive keratoconus and correlate them with alterations in tear cytokine levels, as compared to eyes that remain stable over time.
Setting
This was a prospective observational study (LEC-BHR-P-10-23-1114) included twenty adult patients with bilateral keratoconus, with progressive KC in one eye and stable disease in the fellow eye who were followed up for 6months.
Methods
Eyes with prior ocular surgery, active allergic conjunctivitis or vernal keratoconjunctivitis, current topical medication use, contact lens wear, or hormonal disorders were excluded. Quantitative nerve morphology parameters—corneal nerve branch density (CNBD), total branch density (CTBD), and nerve fiber area (CNFA)—were analyzed using Automated CCMetrics software. Tear samples were collected from each eye at baseline and after six months for quantification of pro-inflammatory cytokines (IL-1α, IL-1β, IL-2, IL-6, IL-17, TNF-α), anti-inflammatory cytokines (IL-4, IL-21), and chemokines (CCL2, CCL3, CCL5, CXCL8, CXCL9, CXCL10) using ELISA.
Results
At baseline, progressive keratoconus eyes showed significantly reduced SBNP parameters compared with stable eyes. CNFD was lower in progressive eyes (14.19 ± 4.06) than in stable eyes (17.17 ± 8.72; p = 0.05). CNBD was markedly reduced in progressive eyes (15.14 ± 3.12) compared with stable eyes (25.61 ± 4.39; p = 0.03). Similarly, CNFL and CTBD were significantly lower in progressive eyes (9.11 ± 2.45 and 26.59 ± 9.19) compared with stable eyes (11.66 ± 4.11 and 42.21 ± 15.84; p = 0.03 and p = 0.05, respectively). Tear cytokine profiling at the first visit demonstrated no statistically significant differences between stable and progressive eyes.
Conclusions
Our results indicate that early and progressive SBNP loss is detectable even when tear cytokine levels remain statistically similar, suggesting that structural nerve alterations may precede biochemical inflammatory changes in keratoconus progression, which need further validation in larger cohort.