Grading of retinal complications in high myopia occurring in Europeans

Abstract

Purpose : Retinal complications are the most important cause of visual decline in high myopia. The most established classification system to diagnose these lesions is META-PM, but this was developed mainly on Asian eyes. Here, we evaluated the performance of the META-PM classification in European eyes, assessed the relation with visual acuity and investigated potential ethnical differences.

Methods : A total of 451 patients with high myopia (spherical equivalent (SphE) ≤-6 D) from the Dutch MYST study were extensively examined using visual function tests and multimodal imaging. With the META-PM grading system, we analysed the type, extent and location of retinal complications on funduscopic photographs. We computed a complication score based on staphyloma, various myopic macular changes, myopic peripapillary atrophy (MPA), and/or a peripapillary intrachorideal cavitation (score range 0-4). We calculated correlation coefficients between parameters and visual acuity (Pearson and Spearman’s correlation coefficient (r_s), for normally distributed and skewed data, respectively), and applied unpaired t- tests to assess differences in visual acuity between complication locations.

Results : The mean age of the participants was 45.8 ± 13.0 years, the percentage men 36.4% and mean SphE was -10.36D ± 3.26. The most frequent lesion was MPA (62.0%) followed by staphyloma (21.4%). For comparison, the prevalence of MPA in Asians was reported to be 81.2% and of staphyloma was 23%. Foveal involvement of the staphyloma was present in 55.1% and was associated with decreased visual acuity (BCVA with vs. without foveal involvement 0.60±0.37 vs 0.85±0.28 (P=1,25E-06)). The occurrence of active CNV or Fuchs spot was rare (0.56% and 1.11% for CNV and Fuchs spot respectively).
A significant correlation was observed between complication score and mean SphE (r_s= -0.428, P= 3,36E-21), mean axial length (r_s= 0.567, P= 8,03E-39) and age (r_s= 0.297, P= 1,76E-10). This was in line with a significant trend (P<0.001) of more complications with lower spherical equivalent, longer axial length and higher age reported in Asians

Conclusions : The META-PM grading system enabled reliable identification and quantification of retinal complications due to myopia in Europeans.The frequency of complications was in line with that of Asians, albeit a slightly lower prevalence of MPA. Awareness of the morbidity of high myopia should be present around the globe.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.