Diagram illustrating ocular anatomy. The anterior segment comprises the cornea (1), anterior chamber (AC), iris (2), ciliary body (3), lens, and posterior chamber (PC). The AC and PC are filled with aqueous humour. The lens is laterally attached to the ciliary body. The posterior segment comprises the vitreous chamber (4) and the posterior ocular wall (5), which is formed by the retina, choroid, and sclera (posterior RCS complex). The vitreous chamber is filled with vitreous humour, and its periphery is called the vitreous capsule or hyaloid. The retina anchors anteriorly at the ora serrata (curved arrow) and posteriorly at the optic disc (6). The choroid anchors anteriorly at the scleral spurs near the ciliary bodies and posteriorly near the exit foramina of the vortex veins (at some distance anterior to the optic disc). Behind the globe, the optic nerve (ON) is seen.