The patient
Patient illustration
Bilateral Asymmetric Keratoconus induced by eye rubbing
Identity : Mr U.N
First visit : 10/22/2012
Last Visit : 01/23/2018
Mr. U.N is a 28-year-old male with no previous medical history or any known history of keratoconus in the family (a brother without keratoconus)
He has a known allergy to pollen and dust mites, and complained of a progressive decrease in visual acuity greater in the left eye than the right.
His refraction at the first visit (10/22th/2012) was : Right Eye (RE) 20/32 with -5.75 (-8.25 x 20 °) and Left Eye (LE) 20/32 with -6.75 (-8.5 x 175 °).
Clinical examination with the slit lamp suggested the possibility of corneal thinning. We also found bilateral Vogt’s striae, Fleischer rings (Fleischer rings are pigmented rings in the peripheral cornea, resulting from iron deposition in basal epithelial cells, in the form of hemosiderin), and tarsal papillae (indicating chronic ocular allergy) in both eyes.
Corneal topography revealed the presence of bilateral keratoconus more pronounced in the left eye.
When asked first about the possibility of frequent eye rubbing, the patient admitted to rubbing his eyes when working in front of the computer, using his fists and knuckles to rub the left eye in particular. The patient is right handed and sleeps on his sides.
We explained to the patient that since vigorous rubbing had preceded the drop in visual acuity, this habit may have caused the cornea to deform in his case. We strongly advised this patient to stop rubbing his eyes and treated his allergy. This included a visit to an allergy specialist to determine the allergens responsible for his symptoms. in particular, the ocular pruritus. The patient decided to comply with our recommendations. He has been followed up by our team for over 5 years. Nowdays he wears slceral contact lens and he definitely stop rubbing his eyes.
Here are pictures of the patient
RIGHT EYE PROFIL. NOTE THE PERI OCULAR ATOPIC SKIN. 
LEFT EYE PROFILE. Note the Dennie-Morgan sign which is a fold or line in the skin below the lower eyelid caused by edema in atopic dermatitis. The presence of Dennie–Morgan folds is used as a diagnostic marker for allergy.
Patient rubbing his eyes with knuckles. Here a video of patient rubbing his eyes
Here are the Orbscan quadmaps, OPDscan (topography and aberrometry) maps and Ocular Response Analyzer (ORA) results of the first visit .
RIGHT EYE ORBSCAN (1st VISIT). Note the severe deformation, very evocative of clinical keratoconus. The cornea is very steep centrally, and very flat peripherally. 
LEFT EYE ORBSCAN (1st VISIT). The keratoconus pattern is obvious, although less marked than on the right eye.
RIGHT EYE OPDscan. The ocular wavefront here is markedly distorted. The increase in higher order aberrations explains the reduction in visual performance, despite the "best " spectacle correction.
LEFT EYE OPDscan. The ocular wavefront is distorted (increase in coma like aberrations). 
RIGHT EYE ORA. Note the reduced height of the applanation peaks, and the reduced CRF (corneal resistance factor) value.
LEFT EYE ORA. Note the reduced height of the applanation peaks, and the reduced CRF (corneal resistance factor) value.Difference maps were performed at each subsequent visit. No evolution was observed between the first and last visits since the patient was properly sensitised to the deleterious effects of eye rubbing. The keratoconus is stable, more than 5 years after the patient definitively stopped rubbing his eyes .
RIGHT EYE ORBSCAN (2nd VISIT)
RIGHT EYE PENTACAM (2nd VISIT)
RIGHT EYE ORBSCAN (3rd VISIT)
RIGHT EYE PENTACAM (3rd VISIT)
RIGHT EYE ORBSCAN (4th VISIT)RIGHT EYE ORBSCAN (4th VISIT)
RIGHT EYE ORBSCAN (5th VISIT)
RIGHT EYE PENTACAM DIFFERENTIAL MAPS (2015 to 2017). As for the right eye, there is no progression between 2015 and 2017.
RIGHT EYE PENTACAM (6th VISIT)
RIGHT EYE PENTACAM DIFFERENTIAL MAPS (2015 to 2018). The results of the subtraction between the data obtained in 2015 and 2017 are shown in the right column. There is no significant difference between the two (green map).
LEFT EYE ORBSCAN (2nd VISIT)
LEFT EYE PENTACAM (2nd VISIT)
LEFT EYE ORBSCAN (3rd VISIT)
LEFT EYE PENTACAM (3rd VISIT)
LEFT EYE ORBSCAN (4th VISIT)LEFT EYE ORBSCAN (4th VISIT)
LEFT EYE ORBSCAN (5th VISIT)
LEFT EYE PENTACAM
DIFFERENTIAL MAPS (2015 to 2017). As for the right eye, there is no progression between 2015 and 2017.
LEFT EYE PENTACAM (6th VISIT)
LEFT EYE PENTACAM DIFFERENTIAL MAPS (2015 to 2018). The results of the subtraction between the data obtained in 2015 and 2017 are shown in the right column. There is no significant difference between the two (green map).This case is another example that illustrates that proper intervention can arrest the progression of kereatoconus. This « proper intervention » comes in the form of a strict cessation of eye rubbing and this has resulted in a stabilization of the corneal deformation over the last 5 years No cross-linking was necessary.
Allergy was the main risk factor in this patient causing intense eye rubbing.
Keratoconus is in essence a topographic syndrome resulting from repeated corneal trauma. The vigorous and repeated eye rubbing over time leads to a weakening of the corneal tissue, which is less resistant, and deforms under the combined forces of repeated mechanical stresses and intraocular pressure which exerts a constant force against the posterior surface of the cornea. Without eye rubbing or mechanical stress, the cornea does not deform.
The deformation of the corneal dome is assessed and quantified best by corneal topography. No histopathological alterations or specific bio-molecular mechanisms have been found in patients and in corneas with keratoconus.
The thinner corneas are generally less resistant and more prone to deform under the action of an identical physical stress than thicker corneas. Thus, keratoconus is more frequently associated with corneas whose central thickness is reduced. It is also probable that the ocular friction generated by repeated eye rubbing induces an additional thinning of the corneal stroma due to the progressive distension of the latter and the induction of secondary inflammatory phenomena liable to cause secondary alteration of the collagen matrix (cellular apoptosis).
