Abstract
Purpose :
We tried to determine if, within a keratoconic population, strong eye rubbing was correlated with visual acuity, spherical equivalent value, biomicroscopic signs, corneal pachymetry, keratometry, and tomography classification determinating keratoconus stage.
Methods :
A retrospective study was performed between november 2014 and october 2015 in the Metz Hospital Center. Were included 33 patients presenting with treatment-naive keratoconus. Patients responded to a questionnaire that assessed eye rubbing habits, family history of keratoconus, history of atopy. 2 groups were separated: group 1 constituted by 15 eyes with no eye rubbing, and group 2 constituted by 18 eyes with moderate or severe eye rubbing. The following informations were collected: best visual corrected acuity (BCVA), spherical equivalent value (SEV), corneal opacities or Vogt striae. For each eye were performed an anterior segment OCT (AS-OCT) to determine the OCT stage for keratoconus (Fourrier domain OCT classification, 2013), and a Scheimpflug camera imaging to determine the maximal keratometry (Kmax) and the minimal corneal thickness (MCT).
Results :
15 eyes were included in group 1 and 18 in group 2; the average age was respectively 28 and 30 years old (p=0.77). Women represented 20% in group 1 and 44% in group 2 (p=0.27). In group 1, 1 patient had family history of keratoconus, versus (vs) 2 in group 2 (p=1). In group 1, 2 patients had history of atopy vs 12 in group 2 (p=0.004). Mean BVCA was 0.33 logMAR in group 1 and 0.58 logMAR in group 2 (p=0.005). Only 1 eye presented corneal opacity in each group (p=1). In group 1, 2 eyes presented Vogt striae vs 9 eyes in group 2 (p=0.034). Mean MCT was 444μm (+/-37μm) in group 1 vs 431μm (+/- 55μm) in group 2 (p=0.39). Mean Kmax was 55.9D(+/-3.3D) in group 1 versus 64.4D(+/-11.9D) in group 2 (p=0.02). Mean SEV was -4.3D(+/-4.4D) in group 1 vs -7.5D(+/-4.8D) in group 2 (p=0.07). In group 1 and 2, AS-OCT respectively showed 14 (93%) and 14(78%) stage 1 keratoconus (p=0.35) ;1 (7%) and 2 (11%) stage 2 (p=1); 0 and 1 (6%) stage 3 (p=1); no stage 4 and 5.
Conclusions :
In our study, eye rubbing is significantly associated with atopic status, decreased visual acuity, more frequent Vogt striae, and increased maximal keratometry. It tends to induce highest spheric equivalent value by increasing astigmatism. We found no difference in minimal pachymetry and OCT stage between the 2 groups.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.