Corneal aberrations in primary congenital glaucoma and its visual correlation

Abstract

Primary congenital glaucoma (PCG) can cause permanent vision loss, and its prognosis is related to early detection and treatment. The main pathological defect consists of resistance to aqueous outflow through the trabecular meshwork due to abnormal development of tissue derived from the neural crest in the anterior chamber angle. Even after successful intraocular pressure (IOP) management in PCG poor visual outcomes still present a lifelong challenge. Vision loss in PCG is multifactorial, resulting from optic nerve damage, corneal scarring, and myopic astigmatism associated with anisometropic amblyopia. Although it is already known that children with PCG present with an altered corneal configuration, the knowledge of irregular astigmatism due to high-order aberrations (HOA) and due to the unequal expansion of the anterior segment, and its impact on visual outcomes, is not yet fully understood, to the best of our knowledge. Quality vision is influenced by the presence of aberrations in the eye's optical system, which can degrade the quality of the image projected onto the retina. Low-order aberrations (LOA), including myopia, hyperopia, and regular astigmatism, can be corrected by spectacles, while HOA cannot be corrected by ordinary means. Coma and spherical aberrations are the most visually significant HOAs, while trefoil and other HOAs have a lower impact on visual quality. The purpose of this article is to establish a quantitative correlation between HOA and visual acuity (VA) to measure the magnitude of the impact of the altered cornea on visual outcomes in PCG.