Fig. 1

Progressive defect of the visual field and the loss of retinal nerve fibre layer in glaucoma. A Normal vision and vision in glaucoma patients. Patients usually experience blurry or missing spots in peripheral vision at early-stage disease. At nearly end-stage disease, only a central vision remains and “tunnel vision” is generated. B Visual field tests of glaucomatous left eyes show early (A), moderate (B), and severe (C) stages of functional loss. Reprinted from Ref. [6] with permission from Elsevier. C The ophthalmoscopic photograph of the retinal nerve fibre layer in healthy individuals (A) show a healthy retinal nerve fibre layer without any defect (red arrows). In patients with glaucoma (B), there are localised reduced reflexes of the retinal nerve fibre layer (light blue arrows), indicating the diminution of retinal nerve fibre layer. Reprinted from Ref. [5] with permission from Elsevier. D The optic disc of healthy individuals without glaucoma shows a normal shape of the neuroretinal rim, with its widest part in the inferior region (A). With glaucoma damage, the cup becomes deeper and larger, and the rim is much thinner than in the healthy optic disc (B). Reprinted from Ref. [5] with permission from Elsevier