Ocular Surface Modulation In Young Allergic Keratoconus: Can Trehalose And Cyclosporine Delay The Need For Cross-Linking?

Keratoconus (KC) in adolescents and young adults, particularly in the presence of allergic disease and eye rubbing, is often characterized by rapid progression leading to early consideration of corneal cross-linking (CXL). However, in patients with good visual acuity, immediate CXL may be perceived as invasive or premature. This study aimed to evaluate whether long-term ocular surface–directed therapy with trehalose-based lubricants and topical cyclosporine A (CyA) is associated with tomographic stabilization in young keratoconus patients and may serve as a noninvasive strategy to delay surgical intervention.

Ankara Bilkent City Hospital

This observational study included 61 consecutive keratoconus patients younger than 23 years treated with trehalose-containing lubricant and topical cyclosporine A. Baseline and follow-up assessments included corrected-distance visual acuity (CDVA), spherical equivalent (SE), and corneal tomography (Pentacam HR). Keratometric indices (Km, Kmax), central corneal thickness (CCT), thinnest corneal thickness (tCCT), and astigmatism were analyzed. Disease progression was strictly defined as an increase of more than 1.0 diopter in Kmax within 12 months and CXL was performed when necessary. Patients were categorized into progression and non-progression groups accordingly.

Mean age was 21.38 ± 3.53 years; 34 patients (55.7%) were female. Of 61 eyes, 54 (88.5%) remained stable and 7 (11.5%) showed progression. In the non-progression group, Kmax (49.73 ± 3.76 vs. 49.76 ± 3.72 D; p = 0.714), Km (p = 0.640), CCT (p = 0.326), thinnest corneal thickness (p = 0.069), astigmatism, spherical equivalent (p = 0.482), and CDVA (p = 0.229) showed no significant change. In the progression group, Kmax increased from 50.99 ± 6.07 to 52.13 ± 6.08 D (p < 0.001) and Km from 45.74 ± 3.77 to 46.06 ± 3.87 D (p = 0.015). Pachymetric parameters remained stable, spherical equivalent showed a nonsignificant myopic trend, and CDVA was preserved. No treatment-related adverse events were observed.

In this young, allergic keratoconus cohort, long-term ocular surface modulation with trehalose and topical cyclosporine A was associated with tomographic stability in nearly 90% of eyes. Progression, when present, involved anterior keratometric steepening rather than significant corneal thinning, while visual acuity remained preserved. These findings suggest that targeting ocular surface inflammation may reduce Kmax steepening in selected young patients. In eyes with good visual acuity, where immediate cross-linking may be overly aggressive, ocular-surface-directed therapy represents a valuable noninvasive strategy to delay intervention. Prospective controlled studies are warranted to confirm its disease-modifying role in early keratoconus.