The fundus usually refers to the structures inside the eye, including the vitreous, retina, choroid or optic nerve. The presence of damage to the fundus, whether it can still be treated and whether it can be restored to normal, depends on the extent of the specific lesion and the type of lesion. If it is a retinal detachment or inflammation of the retina, it can be treated, and if it can be treated aggressively, it can be restored to normal. But if it is a more serious disease, such as retinal atrophy or optic nerve atrophy, this condition cannot be restored to normal. Moreover, the current treatment for fundus disease is mainly restorative, which means that localized lesions appear and need to be treated early so that retinal function can be restored as normal as possible, but there is no such treatment as retinal replacement. Therefore, for the treatment of fundus disease, early detection and early treatment are necessary.