Case #6

The patient

Patient right profile

Bilateral Keratoconus stable since the first visit

Identity : Ms B.N
First visit : 10/05/2016
Last visit : 01/30/2018

32
Age (years)
15
Follow-up (months)

Ms B.N is a 32 year old female with no previous medical history, or any known keratoconus in her family. She complained of a progressive decrease in visual acuity in both eyes over a period of two year .

Her refraction at the first visit was: Right eye (RE)20/25 -1.25 (-3.5 x 15 °) and Left eye (LE) 20/60 -5.5 (-6.25 x 155 °)

Slit lamp examination revealed features of keratoconus in both eyes with thin and steep corneas and Fleischer rings. (Fleischer rings are pigmented rings in the peripheral cornea, resulting from iron deposition in basal epithelial cells, in the form of hemosiderin).

Corneal topography confirmed the presence of bilateral keratoconus, more pronounced of left eye. 

The patient is right handed and spends a lot of time in front of the computer screen. She admitted to rubbing her eyes since teenage period but more vigoursly when she started working on her thesis of history, especially left eye. She rubbed her right eye repeatidly, because of a foreign body sensation due to the contact lens. She sleeps constantly on the left side, causing some left eye compression and contact against the pillow.

She was then advised to stop eye rubbing

PATIENT RIGHT PROFILE
PATIENT LEFT PROFILE
PATIENT DEMONSTRATING HER TECHNIQUE OF EYE RUBBING
PATIENT DEMONSTRATING HER TECHNIQUE OF EYE RUBBING

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

This topography maps strongly suggests the presence of a keratoconus pattern. The elevation maps of the anterior (top right) and posterior (top left) corneal surfaces show increased negative asphericity (hyperprolateness) and toricity (astigmatism). The axial curvature map (bottom left) reveals the presence of a marked inferior steepening. The pachymetry (thickness) map (bottom right) reveals rapid central thinning; These features are typically observed in corneas with keratoconus.
The corneal deformation of the left cornea is severe. The keratoconus of the left eye is slightly more pronounced that that of the right eye.
RIGHT EYE PENTACAM
LEFT EYE PENTACAM
RIGHT EYE ORA
LEFT EYE ORA

Difference maps have been performed at each subsequent visit. The patient was informed that she should stop rubbing her eyes. No evolution has been observed since 15  months.

RIGHT EYE ORBSCAN (2nd VISIT)
PENTACAM DIFFERENTIAL MAPS : RIGHT EYE. To determine if the keratoconus is stable, the best examination is the corneal topography "difference map". The result of two consecutive examinations are subtracted. The right column shows the result of the "point by point" subtraction. Greenish colors correspond to "close to zero" changes. In this case, there is no progression of the corneal deformation between 2016 and 2017.
RIGHT EYE ORBSCAN (3rd VISIT)
RIGHT EYE PENTACAM (3rd VISIT)
PENTACAM DIFFERENTIAL MAPS : RIGHT EYE. The difference map (third column) demonstrates the absence of progression (green and blue colors: stability or flattening).
RIGHT EYE ORBSCAN (4th VISIT)
RIGHT EYE PENTACAM (4th VISIT)
PENTACAM DIFFERENTIAL MAPS : RIGHT EYE. The difference map (third column) demonstrates the absence of progression (green and blue colors: stability or flattening).
LEFT EYE ORBSCAN (2nd VISIT)
PENTACAM DIFFERENTIAL MAPS : LEFT EYE. As for the right eye, this corneal subtraction map demonstrates the absence of any progression. Blueish colors reveal a possible moderate flattening which occurred "spontaneously" (while the patient strictly observed our recommendation to cease eye rubbing). This change corresponds most probably to a random"fluctuation" (within instrument repeatability in the context of a deformed cornea).
LEFT EYE ORBSCAN (3rd VISIT)
LEFT EYE PENTACAM (3rd VISIT)
PENTACAM DIFFERENTIAL MAPS : LEFT EYE. The difference map (third column) demonstrates the absence of progression (green and blue colors: stability or flattening).
LEFT EYE ORBSCAN (4th VISIT)
LEFT EYE PENTACAM (4th VISIT)
PENTACAM DIFFERENTIAL MAPS : LEFT EYE. The difference map (third column) demonstrates the absence of progression (green and blue colors: stability or flattening).

 This case strongly suggests that eye rubbing can trigger keratoconus, even when there are no associated allergies or  atopic conjunctivitis. Contact lens wear can indirectly precipitate keratoconus, as contact lenses often trigger itch and pruritic sensations, leading to eye rubbing.