Choroidal Remodeling Distribution Pattern in the Macular Region in Chinese Young Patients with Myopia

Abstract

Background: The pathogenesis of myopia has been found to be associated with the blood supply of the choroid. This study aimed to determine the relationship between distribution pattern of the choroidal remodeling and the degree of myopia in young patients.Methods: Young patients (age < 18 years) with spherical equivalent of less than -12 diopters (D) were included. Spectral-domain optical coherence tomography (SD-OCT) with enhanced depth imaging (EDI) modality was used to measure the choroidal thickness (CT) and choroidal vascularity index (CVI) in the macular regions. CVI was calculated as the proportion of luminal area to choroidal area and was measured within 1 mm and 3 mm nasal (N1 and N3), temporal (T1 and T3), superior (S1 and S3), and inferior (I1 and I3) to the foveal center. CT and CVI were compared across different ages (i.e., 5~9 years, 10~13 years, and 14~18 years), axial lengths (ALs) (i.e., 21.00~25.00mm and 25.01~29.00mm), and spherical equivalents (SEs) (i.e., SE>-0.5D, -0.5~-3.0D, -3.01~-6.0D, and <-6.0D). Multiple linear regression was applied to examine the associations amongst age, AL, SE, and CVI of different locations.Results: 164 of 172 eyes from 85 volunteers were included. The mean CT in the central foveal was 269.87 ± 63.32µm (ranging from 93.00µm to 443.00µm). The mean sub foveal-CVI was 67.66 ± 2.40% (ranging from 57.84% to 79.60%). Multiple linear regression results revealed significant correlations between SE and T1-CVI (p < 0.05, r2= 0.082, β= 0.194), N1-CVI (p < 0.05, r2= 0.039, β= 0.212). Simple linear regression results revealed that T1-CVI (p < 0.05, r2 = 0.09) and T3-CVI (p < 0.05, r2 = 0.05) were negatively correlated with SE; N1-CVI (p < 0.05, r2 = 0.05) and N3-CVI (p < 0.05, r2 = 0.04) were negatively correlated with SE. Conclusions and Relevance: CVI in the horizontal meridian underwent the largest change as myopia worsened. Temporal and nasal CVIs within the r =1mm and r=3mm sub foveal range were positively associated with degree of myopia in young patients. The CVI value may be used to assess the vascular status of the choroid and be a potential marker of myopic progression.