Mr. H.N is a 28-year-old male without any family history of keratoconus. He was operated in 2013 for a ptosis in the right eye (drooping of the upper eyelid). He has an atopic background (atopic eczema).
He complained of a progressive decrease in visual acuity in the right eye which he noticed since 2014. Corneal topography at that time revealed a unilateral keratoconus in the right eye.
His refraction was: RE 20/60 with -6 (-6.5 x 80 °) and LE 20/20 with -7.25 (-1.25 x 115 °).
Clinical examination with the slit lamp revealed bilateral tarsal papillae, a mild irregular corneal bulge in the right cornea, associated with a Fleischer ring and superficial punctate keratitis. The left cornea was essentially unremarkable.
When asked about eye rubbing, he admitted to rubbing his eyes frequently, more often his right eye than his left. He attributed the preferential rubbing of his right eye to the eczema which was more marked in the right eye, and the ptosis surgery, which caused additional discomfort and irritation.
We explained that chronic right eye rubbing had caused the right cornea to warp permanently, and subsequently advised him to abandon eye rubbing completely. We also advised this patient to have his eczema treated by a dermatologist.
Unilateral keratoconus developed in the right eye of this patient with atopic eczema. Allergy, which affects both eyes, would not alone explain the unilaterality of the keratoconus. The patient admitted to rubbing both eyes, but the right eye more aggressively. In this patient, the left cornea could uphold the rubbing which was less frequent and vigorous. At the subsequent visit, the patient verbalized that he remembered rubbing his right eye very frequently as a child, but he could not explain why the right eye was itchier.
The unilateral asymmetric character of the keratoconus could also be correlated to the ptosis surgery, responsible for a greater discomfort in the right eye (dysfunctional palpebral dynamics), causing greater irritation and consequently more pronounced eye rubbing on this side. It is also possible that chronic eye rubbing could exacerbate the ptosis (chronic palpebral distension causing aponeurotic ptosis).
The cessation of eye rubbing has resulted in the stabilization of the keratoconus in the right eye.