Impact of the Morphologic Characteristics of Optic Disc on Choroidal Thickness in Young Myopic Patients

PURPOSE. To explore the characteristics of tilted optic disc and peripapillary atrophy (PPA), and their associations with choroidal thickness (ChT) in young myopic patients. METHODS. A total of 821 patients were enrolled in this cross-sectional study. Optic disc tilt ratio, PPA area, macular ChT (mChT), and peripapillary ChT (pChT) were measured. Subjects were divided into four groups purely on the basis of the axial length (AL). Relationships between ChT and the morphologic characteristics of optic disc were analyzed using logistic regression. RESULTS. The prevalence of tilted optic disc and PPA increased as myopia severity increased. Every 0.1-mm(2) increase in PPA area was associated with a 14.93-mu m decrease in mChT and a 9.54-mu m decrease in pChT; and every 0.1 increase in tilt ratio was correlated with a 5.38-mu m increase in mChT and a 6.21 decrease in pChT. After stratifying by myopia severity, these trends were still observed in the high myopia group. A larger PPA area (odds ratio [OR] = 2.33; P < 0.01), a longer AL (OR = 1.34; P < 0.01), an increased pChT (OR = 1.11; P < 0.01), and a decreased mChT (OR = 0.93; P < 0.01) were associated with higher odds of having tilted optic disc. CONCLUSIONS. In young myopic patients, mChT was negatively associated with PPA area and positively associated with tilt ratio, while pChT was negatively associated with PPA area and tilt ratio. In this population, larger PPA area, longer AL, and thinner mChT were associated with higher odds of tilted optic disc.