Case #44

The patient

Patient right profile

Bilateral Asymmetric Keratoconus induced by eye rubbing

Identity : Mr N.M
First visit : 05/12/2017
Last Visit : 06/13/2017

46
Age (years)
1
Follow-up (months)

Mr N.M is a 45-year-old male who was initially referred for a refractive surgery suitability assessment. He had no visual symptoms, but requested spectacle and contact lens independence through laser vision correction.

His refraction during the first visit at the Rothschild foundation (on 05/12th/2017) was : Right Eye (RE) 20/20 with +4.50 (-1.5 x 70 °) and Left Eye (LE) 20/20 with +3.25 (-1.75 x 150 °).

Clinical examination with the slit lamp revealed bilateral thin and irregular corneas with Vogt’s striae in the left eye. (Vogt striae are thin vertical streaks located in the posterior corneal stroma, at the level of the Descemet membrane).

Systematic corneal topography performed revealed bilateral keratoconus, more pronounced in the left eye.

At the first visit, when asked about his medical history, he declared that he had no allergies or atopy, and denied any conscious eye rubbing. His job entailed spending hours on the computer every day for many years. He sleeps on the left side with head in the pillow (« pillow hugging »)

We explained to this patient that we would check his topography one month later, and that in the meantime, he should be alerted to the possibility of rubbing his eyes unconsciously in the day. He was told to pay particular attention to certain periods or activities where eye rubbing is commonly performed including the morning upon awakening, under the shower, during work at the computer and after contact lens removal at the end of the day. We also advised the patient that should the need for rubbing arise, he should refrain from doing  so, and to instead instill artificial tears to relieve the itch and fatigue.

When the patient came for his second visit, he declared that he had come to realise that he was rubbing his eyes vigorously when working on the computer, and especially towards the end of the day when he started to feel uncomfortable after prolonged contact lens wear. He would rub his eyes vigorously under the shower in the mornings as well, a habit which was more frequent than he had thought initially.

We then strongly advised the patient to stop the eye rubbing and to change his unhealthy sleeping position.

Here are pictures of patient rubbing his eyes and profiles

PATIENT RIGHT PROFILE
PATIENT LEFT PROFILE
At his second visit, the patient demonstrates how he rubs his eyes many times a day, particularly during extended hours working on the computer .
This alternative technique of eye rubbing is frequently adopted by patients who suffer from Computer Vision Syndrome. The use of the palms provides both itch relief and relaxation. Patients with allergy tend not to rub their eyes this way, but use their knuckles with grinding movements instead.

Here are the Orbscans quadmaps, Pentacam maps, OPDscan (topography and aberrometry) mapsOcular Response Analyzer (ORA) and OQAS (Optical Quality Analyzing System) results of the first visit.

RIGHT EYE ORBSCAN (1st VISIT). The corneal deformation is dominated by asymmetry, due to the inferior sag of the corneal dome. The central cornea is thinned.
LEFT EYE ORBSCAN (1st VISIT). The typical keratoconic deformation is more pronounced on the left eye.
RIGHT EYE PENTACAM (1st VISIT). The information provided is superimposable to that provided by the Orbscan
LEFT EYE PENTACAM (1st VISIT). As for the Orsbcan, the deformation recorded by the Pentacam on the left eye is more pronounced than that of the right eye.
RIGHT EYE ORA. This examination is quite unremarkable.
LEFT EYE ORA. In comparison to the right eye, the peaks have reduced height.
RIGHT EYE OPDscan (1st VISIT). The ocular wavefront is distorted by odd aberration terms (3rd and 5th order coma).
LEFT EYE OPDscan (1st VISIT). The increased prolatennes of the corneal surface leads to an increase in negative spherical aberration and the asymmetry leads to increase in coma like aberrations.
RIGHT EYE OQAS. There is no increase in optical scatter (as expected since despite the corneal distortion, it remains transparent).
LEFT EYE OQAS. The vertical "tail" of the double pass PSF reflects the influence of coma-like aberrations. It may be correlated to symptoms such as monocular or vertical diplopia, ghosting, etc.

Difference maps were performed at each subsequent visit. No evolution was observed between the first and last visits. The keratoconus is stable more than 1 month after the patient had definitively stopped rubbing his eyes. Longer follow-up is of course scheduled.

RIGHT EYE ORBSCAN (2nd VISIT)
LEFT EYE ORBSCAN (2nd VISIT)
RIGHT EYE PENTACAM (2nd VISIT)
LEFT EYE PENTACAM (2nd VISIT)
PENTACAM DIFFERENTIAL MAPS : RIGHT EYE. The 3rd column reveals the absence of significant changes between the first and second examinations.
PENTACAM DIFFERENTIAL MAPS : LEFT EYE. As for the right eye, there is no progression between the 1st and 2nd examination time points.

The diagnosis of keratoconus was made incidentally during a refractive surgery suitability assessment. The patient was visually asymptomatic, and together with the fact that he was 46 years of age at the time of diagnosis suggests that the disease was insidious in onset and progressed slowly. The effect of palm rubbing is not as deleterious as rubbing with the knuckles. Also, for the same rubbing intensity and frequency, some corneas may deform at different speeds, depending on their respective resilience and native properties. There was no genetic background of keratoconus in the family, and again the only risk factor for keratoconus in this case was eye rubbing. Extensive computer use had probably caused visual fatigue, and prompted the frequent rubbing episodes, which made the patient feel better, albeit temporarily. Cessation of the eye rubbing stopped the corneal deformation from progressing.