Correlation analysis of optic disc structure and fundus morphological markers in highly myopic eyes / 中华眼底病杂志

ABSTRACT

Objective:To observe the changes of optic disc structure in patients with high myopia and the correlation with the morphological markers of the fundus.Methods:A retrospective study. From July 2018 to January 2020, 90 patients (155 eyes) diagnosed as high myopia in Department of Ophthalmology of Beijing Friendship Hospital affiliated to Capital Medical University were included in the study. Among them, there were 31 males (52 eyes) and 59 females (103 eyes), with age of 57.1±14.2 years old and axial length (AL) of 28.5±2.6 mm. According to the classification of myopic macular degeneration, patients were divided into 4 groups based on forms and degree of lesions, including non-pathological myopia group, mild traction lesions group, severe traction lesions group and neovascular lesions group, 35, 58, 41, 21 eyes, respectively. The digitized fundus photographs and an Image J system were used to measure the horizontal, vertical, maximal, and minimal diameter of the optic disc, the horizontal and vertical diameter of the parapapillary &delta; zone and γ zone, ovality index, distance between the most superior point of the temporal superior arterial arcade and most inferior point of the temporal inferior arterial arcade (VDA), angle between the temporal arterial arcade and optic disc (angle kappa), distance between the optic disc center and the fovea (DFD), angle between the horizontal disc axis and the disc-fovea line (DFA). The correlation between the diameter of the optic disc and other parameters was analyzed. Univariate and multivariate analysis were used to compare differences between groups.Results:The horizontal diameter of the optic disc was positively correlated with the horizontal diameter of the &delta; zone ( r=0.300, P<0.001), Kappa angle ( r=0.260, P=0.003), and elliptic index ( r=0.650, P<0.001); it was negatively correlated with DFD ( r=-0.190, P=0.030). Optic disc vertical diameter and optic disc horizontal diameter ( r=0.280), &delta;-zone horizontal diameter ( r=0.330) and vertical diameter ( r=0.460), γ-zone horizontal diameter ( r=0.430) and vertical diameter ( r=0.390), DFD ( r=0.390) was positively correlated ( P<0.001); it was negatively correlated with DFA ( r=-0.210, P=0.001) and Kappa angle ( r=-0.210, P=0.004). Compared with the non-pathological myopia group, there were statistically significant differences in the horizontal and vertical diameters of the optic disc in the severe traction disease group ( P<0.05). Among them, the horizontal diameter difference did not depend on the eye axis and age difference; the vertical diameter difference was caused by the eye axis difference. Compared with the non-pathological myopia group, the difference in the horizontal diameter of the optic disc in the neovascular disease group was statistically significant ( P<0.05), and did not depend on the difference in the axis and age; the difference in the vertical diameter of the optic disc was not statistically significant ( P>0.05). Conclusion:The morphology of optic disc was related to several fundus morphological markers, which was differentiated according to the age, AL and the degree of disease in patients with high myopia.