Monochromatic higher order aberrations in highly myopic eyes with Staphyloma

Abstract

ABSTRACT. BACKGROUND: Prevalence of high myopia is continuously increasing, thus, patients affected with staphyloma are abundant worldwide. Assessment of the quality of vision in these patients is mandatory for a proper clinical counselling, especially when undergoing surgical procedures that require intraocular lenses implantation. Thus, the purpose of the study is to assess monochromatic higher order aberrations (HOAs) in highly myopic eyes with without staphyloma compared to those with or without macular bending due to eitherra dome-shaped macula or inferior staphyloma. METHODS: Participants underwent optical coherence tomography, ocular axial biometry, dual Scheimpflug photography and integrated Placido disk topography, and Hartmann-Shack wavefront analysis. Five groups were evaluated: a low-moderate myopia control group (<6.00 diopters, n=31) and four high myopia (≥6.00 diopters) groups: eyes without staphyloma (n=18), eyes with macular bending due to an inferior staphyloma (n=14), eyes with posterior staphyloma without dome-shaped macula (n=15) and eyes with posterior staphyloma with dome-shaped macula (n=17). Subsequently, two new groups (including all participants) were created to assess differences between eyes with and without no staphyloma. One-way analysis of covariance was performed using age and lens densitometry as covariates. RESULTS: Statistically significant (p≤0.05) differences in anterior corneal fourth-order HOAs and spherical aberration were observed between the low-moderate myopia and no-dome-shaped macula and dome-shaped macula groups (0.16 and 0.12 and 0.19, and 0.13 µm, respectively). Anterior corneal tetrafoil was significantly higher (p=0.04) in dome-shaped macula compared to no-dome-shaped macula. When all participants were grouped together, significantly lower mean anterior corneal primary spherical aberration (0.15 µm vs. 0.27 µm, p=0.004) and higher internal primary spherical aberration (0.04 µm vs. -0.06 µm, p=0.04) was observed in staphyloma compared to no-staphyloma myopic patients. CONCLUSIONS: Eyes with high myopia and staphyloma have less positive anterior corneal primary spherical aberration and less negative internal primary spherical aberration, suggesting that the anterior corneal surface tends to mimic in a specular fashion the posterior pole profile. This corneal behaviour appears to change in patients older than 45 years.