Ophthalmologists often come into contact with patients with high myopia, most of whom wear bulky frames and can be separated from the crowd with a single glance. Many patients with high myopia do not pay attention to it at first, and regret when they come to the clinic with significantly reduced vision. Here we have to mention the fundus disease caused by high myopia. We call refractive errors with myopia greater than 600 degrees (children >400 degrees) high myopia, also known as pathological myopia, degenerative myopia, malignant myopia, the course of the disease is mostly progressive, the main anatomical pathological basis for the elongation of the eye axis, with the deepening of the degree, the pathological changes in the eye is gradually aggravated, resulting in a series of fundus diseases. The following will focus on several common fundus diseases that can be caused by high myopia. 1, flying mosquitoes high myopia patients with vitreous degeneration or liquefaction, as the eye turns will feel a black spot floating in front of the eyes, as if mosquitoes flying. This is the projection of some very fine opaque body in the vitreous on the retina. 2.Macular hemorrhage In highly myopic patients, choroidal neovascularization can be formed under the retina in macular area, and the rupture of neovascularization will cause macular hemorrhage, so that the central vision will be greatly damaged. At this time, the patient feels that there is a fixed black shadow in front of his eyes blocking his vision. Although the hemorrhage can be absorbed by treatment, it will always leave more or less blood marks and affect the vision. 3.Macular fissure High myopia can cause macular cystic degeneration, with the prolongation of the disease, the wall of the capsule becomes thinner and thinner, and eventually it will rupture to form a fissure, causing different degrees of damage to vision. Retinal detachment Retinal detachment is one of the common complications of myopia, about 5% of myopic eyes have retinal detachment, which can occur in all degrees of myopia, but the higher the degree of myopia, the greater the tendency to occur. In terms of internal causes, the retinal tissues of highly myopic patients are fragile due to degeneration and atrophy, which makes it easy for the retina to detach and cause blindness. The main external cause is the sudden impact of external force, which is transmitted through the vitreous humor and causes the retina to rupture, resulting in retinal detachment and blindness. So for high myopia, what can patients do on their own? (1) After a thorough examination by an ophthalmologist at a regular hospital, a regular optometry must be performed and appropriate glasses must be worn. (2) Avoid strenuous, impact head sports, such as diving, jumping, etc., to prevent retinal detachment. (3) If there is a sudden loss of vision, black shadows floating in front of the eyes, especially when there is a lightning-like flashing sensation, or if you feel that there is a fixed black shadow in front of your eyes, you should go to the hospital as soon as possible to see a specialist ophthalmologist for an examination, which may be a precursor symptom of some fundus diseases. (4) Eat less spicy food, avoid smoking and alcohol, and use vasodilators carefully to prevent repeated bleeding in the macula of the fundus. (5) Choose your job carefully, avoid heavy physical labor and work that uses too much eye. (6) Regular eye examination and dilated pupil examination of the fundus. (7) Vitamins A, C, E and trace elements zinc and chromium can improve the nutrition and metabolism of the retina, optic nerve and other tissues, and moderate supplementation is helpful for myopia. Finally, I would like to warn all patients and friends that the eyes are the windows to our hearts and minds, and to have a pair of bright glasses, you need to give it enough care, especially for patients with high myopia, it is more important to develop the habit of regular eye examinations to prevent the slightest problem.