Case #92

Case #92

The patient

Patient right profile

Bilateral Asymmetric Keratoconus induced by eye rubbing

Identity : Mr T.U
First visit : 05/22/2018
Last Visit : 11/06/2018

17
Age (years)
6
Follow-up (months)
The crosslinking controversy

Mr. T.U is a 17-year-old male with a history of atopy (eczema and multiple allergies) since childhood. He has no family history of keratoconus (his 2 brothers and 3 sisters all do not have keratoconus).

He presented with a progressive decrease in visual acuity greater in the left eye than the right, and was diagnosed to have keratoconus in October 2017 by an ophthalmologist in another institution. He was advised corneal collagen cross-linking on an urgent basis, as keratoconus progression had been detected in the left eye over several visits. The patient’s mother was unsure about the cross-linking procedure for her son, and upon reading the articles in this website, decided to come to us for a second opinion.

FIRST CONSULTATION 

His refraction at the Rothschild Foundation (on 05/22th/2018) was : Right Eye (RE) 20/25 with -0.25 (-1.00 x 70 °) and Left Eye (LE) 20/40 with -0.75 (-5.25 x 115 °).

Clinical examination with the slit lamp suggested a thin and irregular left cornea with Fleischer ring. (Fleischer rings are pigmented rings in the peripheral cornea, resulting from iron deposition in basal epithelial cells, in the form of hemosiderin).

Corneal topography performed at our institution showed the presence of bilateral keratoconus, more pronounced in the left eye. He had with him a copy of the cornea topographies (Pentacam) that were performed 7 months earlier in the other institution where the diagnosis of keratoconus was first made, and an analysis of these also revealed topographic and aberrometric abnormalities in both eyes, more pronounced in the left eye. Comparison of the Pentacam maps performed at both institutions confirmed that the keratoconus had indeed progressed in both eyes during the 7 month period. 

When asked about the possibility of frequent eye rubbing, the patient admitted to enjoying rubbing his eyes when he awoke in the mornings or when working in front of the computer. His mother, who was present during the consultation, confirmed her son’s eye rubbing habit, and verbalized that he would rub his left eye more frequently and intensely than the right. The patient also recollected rubbing his eyes very vigorously during childhood because of his multiple allergies, with his left eye always being itchier than the right.

He is right handed but would rub his left eye preferentially with his left hand. He sleeps on either side, with the head buried in the pillow (pillow hugging) or on his arms.

We explained to the patient that the vigorous eye rubbing had caused his corneas to deform, leading to the classic clinical presentation of keratoconus in his case.

We strongly advised him to stop rubbing his eyes and to change his unhealthy sleeping position and referred him to a physician to treat his allergies. An eye shield to be worn at night was prescribed to prevent ocular compression and subsequent eye rubbing during sleep. 

SECOND CONSULTATION

The patient informed us that he was fortunately able to comply with most of our instructions and modified his eye rubbing technique to avoid direct compression on the cornea. He also concocted a « home made » ocular protection for sleep (see picture below). His mother however, informed us that he would still rub his eyes occasionally during the day, and she had caught him unawares on several occasions rubbing his eyes vigorously. She would then do her part by reminding him about the deleterious effects of eye rubbing and encourage him to stop.

She was also able to provide us with a timeline of some relevant details on his condition:

2001 to 2006: The family lived in an unpolluted area in ​​Rio, Brazil. There was no eye rubbing during this period.
2008 -2014: They moved to a different neighborhood, which was unfortunately polluted, and the apartment was at some point mold-infested. Eye rubbing commenced during this period. The boy was also spending long hours playing video games, during which he would rub his eyes incessantly.
2016: The family relocated to France (near the countryside) and lived with two pet cats. The boy suffered allergic crises in the spring. The periods of intense eye rubbing continued.
June 2017: The boy started noticing a decrease in vision in the left eye.
October 2017: The diagnosis of keratoconus was made by an ophthalmologist (in another institution in France)
May 2018: Urgent corneal collagen cross-linking was proposed by the ophthalmologist. The mother was hesitant about the cross-linking procedure after reading articles on this website. She decided a second opinion was warranted.

SUBSEQUENT CONSULTATIONS

The mother provided us with videos and photographs of the patient during his younger years, documenting the frequency and intensity of the eye rubbing habit (see below).

The boy was, by this time, able to curtail his eye rubbing habit. 

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

eye with keratoconusPATIENT RIGHT PROFILE. Note the central flattening and the inferior steepening. There is no "protrusion" or "ectasia" but a redistribution of the curvature due to the biomechanical decompensation of traumatic origin (repeated vigorous eye rubbing episodes).
PATIENT LEFT PROFILE. As for the right eye, the deformation of the corneal dome is characterizéd by a central flattening and a paracentral inferior steepening. The biomechanical decompensation of the cornea results in a redistribution of the corneal curvature. This does not correspond to any "ectatic" or "protruding" deformation. In keratoconus, the corneal dome is permanently warped.
PICTURE OF THE PATIENT (TAKEN BY HIS MOTHER) SHOWING HIS SLEEP POSITION. Note the proximity of the forearm to the right orbit.
ANOTHER PICTURE OF THE PATIENT DEMONSTRATING HIS SLEEP POSITION (TAKEN BY HIS MOTHER). Here, the palm is positioned against the orbit.
A CASUAL PICTURE OF THE PATIENT TAKEN IN 2015, INCIDENTALLY FEATURING HIM RUBBING HIS LEFT EYE (Note the intense pressure inflicted on the eye)
THIS IS THE OCULAR MASK CONCOCTED BY THE PATIENT HIMSELF, COMBINING TWO EYE SHIELDS. Nocturnal protection of the eyes is mandatory in such cases where an unhealthy sleep position resulting in compression of the eye, can lead to ocular discomfort and itch and then subconscious incessant rubbing while asleep.

Here is a video graciously sent to us by the patient’s mother, with the patient’s consent, for use in this website.

The video reveals the patient’s eye rubbing habits during childhood. Notice how he tends to rub his left eye a lot more often and vigorously. His technique of eye rubbing correlates well with the topographic changes seen (see section below).  The infero-nasal corneal deformation in the left eye corresponds to the area receiving maximal compression from the knuckles and fingernails during rubbing. The less frequently and less vigorously rubbed right eye is also deformed, but not as severely.

INITIAL TOPOGRAPHIES (PERFORMED AT ANOTHER INSTITUTION (10/11/2017))

RIGHT EYE PENTACAM These maps show a typical mild keratoconus pattern. The cornea is hyperprolate (conical shape). It is also irregular. The repeated trauma has caused the cornea to "buckle" centrally.This explains the steepening of the corneal apex.
LEFT EYE PENTACAM: As for the right eye, the cornea is irregular, very prolate (central steepening and consecutive peripheral flattening). The deformation in the left eye is slightly more pronounced than that in the right eye.

FIRST TOPOGRAPHIES AND EXAMINATIONS AT ROTHSCHILD FOUNDATION (05/22/2018)

RIGHT EYE ORBSCAN: This examination shows moderate deformation with inferior steepening, evocative of keratoconus. Both the anterior and posterior elevation maps are showing increased positive elevation centrally.
LEFT EYE ORBSCAN: The corneal deformation is obvious: it is characterized by an irregular infero-central steepening. The corneal surfaces are hyerprolate, and there is marked central thinning
RIGHT EYE PENTACAM: This examination shows a moderate degree of irregular astigmatism, and a suspicion of thinning in the paracentral cornea.
LEFT EYE PENTACAM: This examination shows the presence of keratoconus with increased prolateness and central thinning.
RIGHT EYE HIGH RESOLUTION OCT EPITHELIAL THICKNESS AND PACHYMETRY MAP. Note the slight increase in the thickness of the epithelial layer in the center.
LEFT EYE HIGH RESOLUTION OCT EPITHELIAL THICKNESS AND PACHYMETRY MAP. Note the slight increase in the thickness of the epithelial layer in the paracentral area.
RIGHT EYE OPD Scan III examination (combined topography and aberrometry). The irregularity of the corneal surface results in moderate induction of coma and positive spherical aberration. These aberrations explain the visual symptoms of the patient (perception of ghosts and multiple images)
LEFT EYE OPD Scan III examination (combined topography and aberrometry). The slight irregularity of the corneal surface results in moderate induction of coma and positive spherical aberration. These aberrations explain the visual symptoms of the patient (perception of ghosts and multiple images).

Difference maps were performed at each subsequent visit. No evolution has been observed between the first and last visits. The keratoconus is stable, more than 6 months after the patient definitively stopped rubbing his eyes .

RIGHT EYE ORBSCAN (2nd VISIT). Stable since first visit.
LEFT EYE ORBSCAN (2nd VISIT). Stable since first visit.
RIGHT EYE PENTACAM (2nd VISIT). Stable since first visit.
LEFT EYE PENTACAM (2nd VISIT). Stable since first visit.
PENTACAM DIFFERENTIAL MAPS : RIGHT EYE. (between first and second visits). This difference map demonstrates the absence of progression of the corneal irregularities since the patient definitively stopped rubbing his eyes
PENTACAM DIFFERENTIAL MAPS : LEFT EYE. (between first and second visits). This difference map demonstrates the absence of keratoconus progression. Like most of the cases in this website, the cessation of eye rubbing suffices to stabilize the corneal deformation.
RIGHT EYE ORBSCAN (3rd VISIT). Stable since first visit.
LEFT EYE ORBSCAN (3rd VISIT). Stable since first visit.
PENTACAM DIFFERENTIAL MAPS : RIGHT EYE. (between first and third visits). This difference map demonstrates the absence of progression of the corneal irregularities since the patient definitively stopped rubbing his eyes
PENTACAM DIFFERENTIAL MAPS : LEFT EYE. (between first and third visits). This difference map demonstrates the absence of progression of the corneal irregularities since the patient definitively stopped rubbing his eyes

We have presented an archetypal case of keratoconus here: A young man with a history of allergies since childhood rubs his eyes habitually and incessantly. He has an unhealthy sleep position, compressing his eyes with his arms and palms. He develops blurring of vision after a few years of vigorous eye rubbing and is then diagnosed with keratoconus by an ophthalmologist. The eye rubbing habit goes unnoticed, he continues to rub, and the keratoconus progresses. The ophthalmologist, oblivious to the association between eye rubbing and keratoconus genesis and progression, offers urgent corneal collagen cross-linking as a therapeutic measure.

Fortunately for this young man, he has an informed and motivated parent (his mother), who upon reading the articles in this website, was made aware of the direct causal effect of eye rubbing on the pathogenesis of keratoconus, and became skeptical about the need for cross-linking for her son, and made a decision to seek a second opinion.

The simple act of cessation of eye rubbing has arrested the progression of keratoconus in this case. No corneal collagen cross linking was required.

 

There are several other learning points in this case:

ASYMMETRIC NATURE OF KERATOCONUS DEVELOPMENT

The asymmetric nature of keratoconus development is related to the habit of preferentially rubbing the left eye. Once again, the technique of eye rubbing (refer to the videos) determines the severity of keratoconus.  Rubbing with the knuckles or nails, the hardest part of the hands, is particularly detrimental, as it inflicts severe biomechanical stress on the cornea.

KERATOCONUS AND OCULAR ALLERGY

Ocular allergy has often been associated with keratoconus, but in our opinion, this association is not a true association. The pertinent link is between KERATOCONUS and EYE RUBBING, which is triggered by pruritus (itch) from ocular allergy. Atopic and allergic patients who do not incessantly rub their eyes are not susceptible to develop the corneal deformation seen in keratoconus.

KERATOCONUS AND THE YOUNG CORNEA

As seen in this case, the risk of keratoconus progression is higher in the young, as the corneas of young patients are less rigid and prone to deformation (corneas stiffen naturally with increasing age). Although young patients in general tend to be less compliant to advice and recommendations, if proper and diligent explanations on the benefits of curtailing the eye rubbing habit are enforced, the outcome can be truly rewarding. During the 7 month period from the time of diagnosis of keratoconus, there was an obvious and rapid progression of the disease in both eyes. Within 6 months of cessation of eye rubbing, definite disease stabilization was achieved, once again highlighting the important role of eye rubbing in keratoconus genesis and progression.

ELUCIDATING THE EYE RUBBING HABIT

It is very important to spend time with the patient to elucidate the triggers and reasons for eye rubbing. Often the answers are not apparent at the first consultation, because the patient is not always conscious of the habit. Hence the importance of re-interrogating the patient at each consultation to make him or her aware of his or her rubbing habits. Help and support from friends and family members can be invaluable. This patient’s mother has been doing a great job alerting her son to unconscious rubbing episodes, thus increasing his awareness of the problem.

THERE IS NEVER AN URGENCY TO PERFORM CORNEAL COLLAGEN CROSS-LINKING FOR KERATOCONUS

In many centers, corneal collagen crosslinking (CXL) is often suggested immediately or on an urgent basis to patients upon diagnosis of keratoconus. As demonstrated in this case, this practice is unnecessary. In this patient, despite a young age and supposed « aggressive keratoconus », stability of keratoconus  was attained simply by the cessation of eye rubbing. 

WHAT IF CORNEAL CROSS-LINKING (CXL) HAD BEEN PERFORMED?

If CXL had been performed and the patient concomitantly stopped the eye rubbing habit (which is not uncommon as patients are often fearful of rubbing the eye after a surgical procedure), the stability of the disease would have been wrongly attributed to the success of the CXL procedure.  Conversely, if CXL had been performed and the patient continued to rub his eyes, it is likely that the keratoconus would continue to progress, as the force exerted on the cornea would still exceed any purported corneal strengthening achieved by the CXL procedure, resulting in continued weakening of the cornea.

  • Date 16 juillet 2018
  • Tags Allergy, Asymmetric, Bilateral keratoconus, Childhood rubbing, Eczema, Enjoyed eye rubbing, Eye rubbing, Inferior keratoconus, Knuckles rubbing, Male, Morning rubbing, Sleep position, Stabilization, Witness, Youngest