Long-term Multicenter Analysis of Axial Length and ATN Grading in Myopic Choroidal Neovascularization

Abstract

INTRODUCTION: High myopia is the leading cause of vision loss, especially when associated with choroidal neovascularization (CNV). Despite advances in understanding myopic maculopathy (MM), its definition and relationship with axial length (AL) are not established. AL has been proposed as an essential factor in MM. Our aim was to analyze the relationship between AL, treatment, and MM progression in myopic eyes with CNV, based on the atrophy-traction-neovascularization (ATN) classification.

METHODS: Retrospective multicenter study that included patients with treated myopic CNV and a minimum follow-up of 5 years from two centers: Unidade Local de Saúde (ULS) de Coimbra and ULS de São João. Patients were grouped into: non-pathological myopia (nPM, AL <28 mm), pathological myopia (PM, AL ≥28 mm) and severe (sPM, AL ≥29.5 mm). A linear regression model was used to predict MM progression.

RESULTS: Forty-two eyes (73.8% women) from 42 patients were divided: 12 in the nPM group, 11 in PM and 19 in sPM. Mean follow-up was 127.57±43.77 months (10.6 years). The sPM group had younger patients (50.84±12.86 years) than the PM group (62.68±11.19 years) (p=0.045). Mean central choroidal thickness (CCT) of all patients was 79.9 ± 47.6 mm, with significant thinning in sPM (p=0.025) and in eyes with posterior staphyloma (p=0.033). Worse final VA correlated with increased age and with the initial atrophy (A) component (r=-0.34, p=0.029; r=-0.41, p=0.007). CCT correlated with the initial A component (r=-0.38, p=0.036). Age at diagnosis (B=0.28, p=0.016) and presence of staphyloma (B=1.00, p=0.023) were associated with a higher risk of MM progression.

CONCLUSION: This study highlights that the development and progression of chorioretinal atrophy is not limited to simple AL measurement. In fact, age at diagnosis and posterior staphyloma were significantly associated with MM progression, and choroidal atrophy was associated with retinal atrophy. This indicates that the three-dimensional shape of the eye, and changes in the sclera and choroid at the posterior pole, may play a relevant role in progression. Our analysis offers insights into MM and underscores the need for close monitoring of these patients.