Objective: This study aimed to compare the macular and choroidal thicknesses and blood-flow parameters of patients with intermediate and simple juvenile moderate myopia in order to provide a greater understanding of the pathogenesis of myopia and a basis for its prevention.
Methods: Participants were selected from patients under the age of 18 with moderate myopia who were treated in our ophthalmic clinic between June and December 2019. Seventy-five right eyes were selected from participants with a mean spherical equivalent ranging from -6.0 to -3.0 D. These samples were divided into two groups based on eye axial length (AL). The thicknesses of the macula and choroid, the area of the foveal avascular zone (FAZ), and the blood flow density of the macular capillaries were measured, intergroup comparison was conducted.
Results: The average area of the FAZ was larger in the intermediate group than in the simple group. PERIM in the upper half was lower in the intermediate group than in the simple group, and the blood-flow density in the lower half of the macular area was higher in the simple group than in the intermediate group. The blood-flow density within 1 mm of the fovea centralis and the downward blood-flow density were higher in the intermediate group than in the simple group. The thicknesses of the lower part of the FAZ, the choroid of the fovea centralis, and the choroid under the retina were all larger in the intermediate group than in the simple group.
Conclusion: The area of the FAZ in patients with intermediate juvenile moderate myopia is larger than that in patients with simple myopia; the choroid in the fovea of macula compensatorily increases, and blood flow density also increases; the thickness of the choroid under the retina increases with myopia.
Keywords: choroidal blood flow; choroidal thickness; moderate myopia; myopic adolescents; optical coherence tomography angiography.
© 2021 Lin et al.