Associations of fundus tessellation, myopic diffuse chorioretinal atrophy and choroidal thickness with visual acuity in myopia.

PURPOSE

To explore associations between stages of myopic macular degeneration (MMD) and visual acuity and influencing parameters.

METHODS

Participants of the population-based study Beijing Eye Study (n = 3468 participants) underwent a detailed ocular and systemic examination.

RESULTS

Assessable images were available for 3040 (87.7%) individuals (age: 64.0 ± 9.7 years). In multivariable analysis, worse best-corrected visual acuity (BCVA) (i.e. higher logMAR values) was associated with higher MMD stage (beta: 0.11; B: 0.06; 95%

CI

0.04, 0.08; p < 0.001) and thinner subfoveal choroidal thickness (beta: -0.06; p = 0.002), with adjustments for age, sex, educational level, cognitive function, degree of any cataract and prevalence of glaucoma, diabetic retinopathy and age-related macular degeneration. If only eyes with MMD grade 1 or no MMD were included, worse BCVA was associated (multivariable analysis) with higher prevalence of MMD stage 1 (beta: 0.11; B: 0.07; 95%

CI

0.05, 0.09; p < 0.001) and thinner medium-sized choroidal vessel layer thickness. Correspondingly, BCVA was worse in eyes with MMD stage 1 than in eyes without MMD (0.13 ± 0.27 logMAR vs. 0.04 ± 0.14; p < 0.001). Including only eyes without vision-influencing disorders (except myopia), BCVA was also worse in eyes with MMD stage 1 than in eyes without MMD (0.06 ± 0.13 logMAR vs. -0.01 ± 0.08 logMAR; p < 0.001). In these eyes without vision-influencing ocular disorders, worse BCVA was associated with thinner total subfoveal choroidal thickness (beta: -0.15; R: 0.000; 95%

CI

0.000, 0.000; p < 0.001) and longer axial length (beta: 0.14; R: 0.01; 95%

CI

0.01, 0.02; p < 0.001), or alternatively with higher MMD staging (beta: 0.24; R: 0.09; 95%

CI

0.01, 0.11; p < 0.001).

CONCLUSIONS

MMD stage 1 (fundus tessellation) is associated with decreased BCVA and may be considered pathological. Independently of longer axial length, thinner choroidal thickness is a factor associated with lower BCVA in myopic eyes, including eyes with MMD stage 1.