The retina is a very important anatomical structure in the eye, similar to the negative in a camera, commonly known as the fundus. Common clinical fundus lesions mainly include the following categories: 1, retinal vascular diseases: mostly caused by retinal artery or vein obstruction causing fundus hemorrhage; 2, retinal pigment epithelium with lesions and loss of photoreceptor cells, which can cause hereditary diseases, such as retinitis pigmentosa; 3, macular lesions: generally occurring in the most sensitive part of vision, such as macular fissure, macular detachment, macular edema, macular hemorrhage, etc.; 4, Retinal posterior surface and choroidal two-layer shared diseases; 5. Retinal detachment: more serious, can affect vision, need timely surgical treatment; 6. Retinal tumor.