ObjectiveTo investigate the incidence and influencing factors of optic disc changes in children and adolescents with high myopia. MethodsA clinical cross-sectional study. A total of 162 children and adolescents with high myopia (162 eyes) who visited Department of Ophthalmology, Northern Jiangsu People's Hospital Affiliated to Yangzhou University from January to April 2025 were included in this study. Myopia refractive error ≥ 6.00 D and/or axial length (AL) ≥26 mm. All participants underwent best-corrected visual acuity, refraction, fundus color photography, swept-source optical coherence tomography (SS-OCT), and AL measurement. Subfoveal choroidal thickness (ChT) was measured within 1 mm using SS-OCT. Optic disc changes assessed included tilt, rotation, peripapillary atrophy (PPA), and peripapillary hyperreflective ovoid mass-like structures (PHOMS). The patients were divided into the children group (4-11 years old) and the adolescents group (12-18 years old) based on age, with 63 (38.9%, 63/162) and 99 (61.1%, 99/162) cases respectively. The incidence of ocular features and optic disc morphology changes in the two groups was compared and observed. According to the myopia diopter, the patients were divided into the high diopter long axial group (myopia diopter ≥ 6.00 D, AL≥26 mm) and the low diopter long axial group (myopia diopter ＜6.00 D, AL≥26 mm), with 85 (52.5%, 85/162) and 77 (47.5%, 77/162) eyes respectively. The incidence of optic disc morphological changes in the two groups was compared and observed. The comparison of quantitative data between groups was conducted using the Mann-Whitney U test. Multivariate logistic regression was used to analyze the correlations between PPA, optic disc tilt, PHOMS occurrence and gender, age, diopter, AL, and ChT. ResultsAmong the 162 patients, 103 were male and 59 were female. Age was 12 (10.5, 13.5) years old. Among the 162 eyes, the optic disc morphology changed in 152 eyes (93.8%, 152/162). Among them, the PPA, optic disc tilt, PHOMS, and optic disc rotation were 148 (91.4%, 148/162), 95 (58.6%, 95/162), 62 (38.3%, 62/162), and 35 (21.6%) eyes respectively. Myopic macular degeneration in 137 eyes. There were 56 eyes with peripheral retinopathy. There was no statistically significant difference in myopia diopter, AL and ChT between the children group and the adolescent group (Z=−1.201, −1.934, −0.761; P=0.230, 0.053, 0.447). There was no statistically significant difference in the incidences of PPA, optic disc tilt and optic disc rotation (χ2=0.293, 2.618, 0.398; P > 0.05). There was no statistically significant difference in the incidence of optic disc morphological changes between the low diopter long axial group and the high diopter long axial group (χ2=0.000, P > 0.05). The results of multivariate logistic regression analysis showed that the thinner the ChT, the higher the risk of PPA [odds ratio (OR) =0.98, 95% confidence interval (CI) 0.97-0.99, P ＜0.001]. Female (OR=2.3, 95%CI 1.04-5.07, P=0.039), older age (OR=1.17, 95%CI 1.01-1.37, P=0.043), thinner ChT (OR=0.99, 95%CI 0.99-1.00, P=0.012), the higher the risk of optic disc tilt. The older the age, the higher the risk of developing PHOMS (OR=1.22, 95%CI 1.06-1.40, P=0.006). ConclusionOptic disc morphology changes may be the most common fundus alterations in children and adolescents with high myopia.