Dr Ared's research into eye rubbing and keratoconus has produced novel findings that have changed the way we think about this disease. Globally, keratoconus affects 138 people per 100,000, but the prevalence may be higher. If there is a known family history of keratoconus or if you are a known eye rubber, you may want to come in for a proper assessment.
Download Dr Ared’s thesis on: The Ocular Response to eye rubbing in keratoconus
Keratoconus and Corneal Assessments
ABSTRACT
This thesis examined the impact of eye rubbing on corneal shape and anterior eye structure in individuals with keratoconus (KC) (KC, n = 60) and those without (Non-KC, n = 60). Secondary aims included determining the repeatability of corneal epithelial thickness (CET) and corneal densitometry (CD) measurements, assessing habitual eye-rubbing behaviours, and the relationships between KC disease severity, rubbing habits, and the degree of corneal and structural changes after rubbing.
The repeatability of CET and CD measurements, using Swept-Source Tomography and Scheimpflug imaging, respectively, was evaluated. There were no significant differences between KC and Non-KC in CET for any coefficient of repeatability (CoR). CET had the highest repeatability at the central cornea (CoR = 4.4 ?m) compared to the peripheral locations (CoR = 11.5 - 12.5 ?m). CD repeatability was lower in KC (CoR = 1.0 - 3.7 grey scale units (GSU)) compared to Non-KC (CoR = 0.9 - 1.2 GSU), especially in the anterior regions. The central CET was thinnest in KC; the temporal CET was thickest in Non-KC. KC had a thicker nasal CET compared to Non-KC (p = 0.002). The anterior regions had the highest CD in both groups, with no differences between groups for CD in any region (p > 0.05). KC severity was associated with a thinner central CET (? = -0.60, p = 0.002) and higher CD in three regions (? = 0.48 - 0.78, p ? 0.02).
A self-reported survey revealed that a higher proportion of KC individuals rubbed their eyes more frequently (p = 0.005), forcefully (p < 0.001), and for longer durations (p < 0.001) than those without KC. A higher proportion of KC used palms (p = 0.002) and knuckles (p = 0.003). The duration of rubbing was positively correlated with KC severity (? = 0.43, p = 0.01).
Immediate corneal response to habitual eye rubbing was assessed. KC showed thinner CET post-rub (mean difference (MD) = 3.2 ?m, p < 0.001) and increased CD (MD = 0.8 GSU, p < 0.001), whereas there were no changes in Non-KC (p > 0.05). Both groups showed reduced anterior and posterior corneal curvatures (p < 0.001) and decreased ACV (p ? 0.04) post rub. Disease severity was associated with increased CD (? = 0.43, p = 0.01) and decreased anterior radius of curvature (? = -0.43, p = 0.01) after rubbing.
These findings highlight the cornea's vulnerability to rubbing-related ocular trauma, especially in KC, and emphasise that controlling abnormal rubbing behaviours in KC is essential for managing the disease.
