Fig. 6.

VEGF derived from RPE is necessary for choriocapillaris development and maintenance, which is essential for overall ocular size development and maintenance. The development of emmetropic eyes requires VEGF derived from RPE to promote the development of choriocapillaris and maintain their physiological thickness. The decrease of VEGF derived from RPE can cause choriocapillaris dysplasia, and the thinner choroid thickness will promote axial length elongation and result in myopia. In a word, generous physiological secretion of VEGF is essential for choriocapillaris and axial length maintenance, while in the case of hypoxia in high-myopia, local pathological secretion of VEGF results in the formation of myopic choroidal neovascularization.