Higher order aberrations and glare disability in Mild Keratoconus: A comparative study

Purpose : To quantify glare-induced contrast sensitivity deficits across spatial frequencies in mild keratoconus and compare these functional impairments to age-matched controls. Method : Eighteen eyes with early keratoconus (grade 0–1, Belin ABCD) to age-matched controls. Visual acuity, wavefront aberrometry, and contrast sensitivity (CSV-1000HGT) were evaluated under baseline and glare conditions using best spectacle correction. Contrast thresholds were recorded across four spatial frequencies. Group differences were analyzed using non-parametric statistical tests. Results : Median age and visual acuity were similar between groups, though the Mild KC group had reduced acuity (0.13 log MAR). Higher-order aberrations (HOA) were significantly elevated in Mild KC (0.139 vs. 0.028; p < 0.05). Contrast sensitivity declined under glare in both groups, but significantly only in controls. Mild KC showed a 4% reduction vs. 3% in controls. A strong positive correlation was found between HOA and contrast sensitivity (R = 0.82, p < 0.05). Conclusion : Mild KCs are also associated with significantly elevated HOA and subtle but notable reduction in contrast sensitivity under glare, despite comparable median visual acuity between groups, the Mild KC cohort exhibited a greater reduction in AULCSF with glare exposure, although the effect of glare as defined by Glare disability doesn’t tend to differ significantly among the two groups.