Ms N.D is a 25-year-old female student with no previous medical or ophthalmic history, or any known keratoconus in the family. She has atopic dermatitis (eczema) since her teenage years. She complained of a progressive decrease in vision in the right eye only, for the past 6 months.
Her Refraction was : Right Eye (RE) 20/25 with -0.25 (-2.25 x 175 °) and Left Eye (LE) 20/20 with -0.5 (-0.5 x 110 °).
Slit lamp examination revealed keratoconus with a discernable Fleischer ring in the right eye (a Fleisher ring, formed by iron deposits within the corneal epithelium which is then stained brown, is commonly observed in keratoconus). The left cornea was unremarkable. Bilateral tarsal conjunctival papillae and periorbital eczema were also present.
Corneal topography revealed a frank keratoconus pattern in the right eye, and a forme fruste keratoconus (subtle vertical asymmetry on the corneal curvature map) in the left eye.
She admitted to rubbing her eyes with the knuckles frequently in an attempt to relieve her itchy eyes and swollen eyelids, especially on the right side. She is right handed.
The deleterious role of eye rubbing was thoroughly explained to the patient, and she was strongly advised to stop rubbing her eyes.
Here are pictures of the patient demonstrating her eye rubbing technique, and her profiles
Note the presence of the Dennie Morgan infraorbital fold or line on the skin below the lower eyelid in the right profile picture. This is caused by edema in atopic dermatitis. Dennie–Morgan folds are due to stretching of the skin from eye rubbing and is a useful marker for allergy affecting the eyes.
Atopy is frequently associated with keratoconus. In this case, the patient has chronic eczema responsible for palpebral and ocular surface inflammation, creating severe ocular pruritus and the intense desire to rub the eyes.
Asymmetry of ocular involvement in allergic disease is often observed. Although the patient admitted to rubbing both eyes, the asymmetrical involvement resulted in a more symptomatic right eye which was subsequently rubbed more vigorously and frequently. This patient is right-hand dominant, and this may also account for more intense rubbing on this side. Also, the rubbing technique as described by the patient was different from one hand to the other (knuckles in a grinding rotary fashion in the right eye, vs more gentle lateral movements with the pulp of the fingers in the left eye). These factors must be thoroughly elucidated during the clinical examination of any patient with keratoconus. It is mandatory to sensitize the patient to the role of eye rubbing in the keratoconus pathway, and strongly recommend them to definitively stop eye rubbing in order to arrest the process causing the corneal deformation.