Keratoconus, which causes the cornea to become thinner and steeper, is perhaps most commonly associated with eye rubbing. Regular, traumatic vicissitude of eye rubbing can weaken the cornea, creating bulging, thinning and structural failure. The likely pathogenesis 
is multifactorial, with a wide range of genetic loci suggesting the disease is dependent on external influences that lead to initiation and progression. 

Associated ocular and systemic conditions include, but are not limited to, atopic eczema, asthma, allergic eye diseases, Down’s syndrome, collagen vascular diseases and retinitis pigmentosa. Keratoconus is known to affect between one in 400 and one in 2000 – mainly young – people worldwide (Godefrooij et al, 2017).