Purpose: We investigated the vascular system in the far peripheral retina in eyes with pathologic myopia by ultra-widefield fluorescein angiography (FA).
Methods: We analyzed retrospectively 230 with pathologic myopia (myopic refractive error >8 diopters [D] or axial length >26.5 mm) and 42 emmetropic (refractive error < ± 2 D) controls who were examined with ultra-widefield FA by the Optos P200 system. Far peripheral retina was defined as the area anterior to the ampullae of the vortex veins.
Results: Retinal capillary telangiectasia was observed in the far periphery of 34 of 42 (81.0%) emmetropic eyes and in 90 of 115 (78.3%) highly myopic eyes. Retinal capillary microaneurysms were observed in 13 of 42 (31.0%) emmetropic eyes and in 60 of 115 (52.2%) eyes with pathologic myopia. The differences in the incidences of these two lesions were not significant. Areas of nonperfusion in the far periphery were found in two of 42 (4.8%) emmetropic eyes and in 95 of 115 (82.6%) eyes with pathologic myopia. In these myopic eyes, the arterioles and venules had an abrupt ending, and in advanced cases, the perfused area was limited to just beyond the staphyloma border. None of the eyes developed retinal neovascularization. Statistical analyses showed that the highly myopic patients with avascular areas in the far periphery were significantly older, and had significantly longer axial length.
Conclusions: Areas of nonperfusion in the far periphery are common in eyes with pathologic myopia. Retinal vasculature in the far periphery is significantly altered in eyes with pathologic myopia, and this may be due to a mechanical stretching.
Keywords: pathologic myopia; peripheral retina; wide-field angiography.