Case #22

The patient

Patient right profile

Bilateral Asymmetric Keratoconus induced by eye rubbing

Identity : Mr C.B
First visit : 02/17/2015
Last Visit : 04/18/2017

29
Age (years)
26
Follow-up (months)

Mr. C.B is a 29-year-old male baker with no previous medical history or history of keratoconus in his family .
He has known allergy to dust mites, and complained of a progressive decrease in visual acuity greater in the left eye than in the right .

His refraction at the first visit (02/17th/2015) was : Right Eye (RE) 20/20 with -0.75 (-0.75 x 50 °) and Left Eye (LE) 15/20 with -1.5 (-4,75 x 90 °).

Clinical examination with the slit lamp revealed bilateral keratoconus with 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 which was more pronounced in the left eye.

He was advised by ophthalmologists in another institution to undergo corneal collagen cross-linking urgently, but he decided to consult us for a second opinion instead.

When asked about eye rubbing, the patient admitted to rubbing his eyes frequently (with the knuckles) everyday, especially while at work in the bakery. He also rubbed his eyes vigorously in the mornings, resulting in frequent red eyes. He is right-handed and sleeps on his left side .

We strongly advised this patient to stop rubbing his eyes, and explained to him that eye rubbing was responsible for the onset and progression of keratoconus in his case. We also treated his allergy, and this included a specialized visit to an allergy specialist to determine the allergens responsible for his symptoms and for subsequent desensitisation.

Here are pictures of the patient rubbing his eyes and his corneal profiles

PATIENT RIGHT PROFILE
PATIENT LEFT PROFILE
PATIENT RUBBING HIS RIGHT EYE
PATIENT SHOWING HIS SLEEPING POSITION (LEFT SIDE)

Here are the Orbscan quadmaps, Pentacam maps and Ocular Response Analyzer (ORA) results of the first visit .

RIGHT EYE ORBSCAN (1st VISIT)
RIGHT EYE PENTACAM
RIGHT EYE ORA. Note the reduced height of the applanation peaks, and the reduced CRF (corneal resistance factor) value.
LEFT EYE ORBSCAN (1st VISIT)
LEFT EYE PENTACAM.
RIGHT 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. The keratoconus is stable, more than 2 years after the patient definitively stopped rubbing his eyes .

RIGHT EYE ORBSCAN (2nd VISIT)
LEFT EYE ORBSCAN (2nd VISIT)
RIGHT EYE PENTACAM (2nd VISIT)
LEFT EYE PENTACAM (2nd VISIT)
RIGHT EYE ORBSCAN (3rd VISIT)
LEFT EYE ORBSCAN (3rd VISIT)
RIGHT EYE ORBSCAN (4th VISIT)
LEFT EYE ORBSCAN (4th VISIT)
PENTACAM DIFFERENTIAL MAPS : RIGHT EYE. No significant changes are detected.
PENTACAM DIFFERENTIAL MAPS : LEFT EYE; As for the right eye, there is no keratoconus progression in the left eye between the first and second visits.

The asymmetry of keratoconus development may be related to the sleeping position (left side) and the habit of preferentially rubbing the left eye. In the presence of allergies, the rubbing intensity is often more intense and more repetitive.

This case is very informative and demonstrative of the direct causal effect of eye rubbing in the pathogenesis of keratoconus. Allergy is a classic risk factor for the disease, but this association exists probably because allergic patients tend to rub their itchy eyes more often and more firmly than non-allergic patients.

Eye rubbing is frequently overlooked by patients and clinicians, but if made aware, standard advice on avoiding vigorous and prolonged rubbing are sometimes ineffective, even when repeated. Time is needed to counsel and educate patients and their family members on the deleterious effects of eye rubbing on keratoconus genesis and progression. Cross linking is never an urgent procedure and should not be suggested to patients without managing the eye rubbing habits of the patients first. As our wide experience shows, the cessation of eye rubbing is most important and this approach alone is sufficient to stabilize corneas with keratoconus at any stage. A dialogue on eye rubbing with the patient often suffices and avoids a potentially invasive intervention. We believe that cross-linking may have an indirect role in stopping eye rubbing, as like any surgical procedure to the eye, it desensitizes the cornea.

Like many of the other cases in this site, this case demonstrates that the cessation of eye rubbing and proper allergy therapy are the best tools in the prevention of the onset and/or evolution of keratoconus. Prevention is the key.