What is high myopia? High myopia is an eye disease characterized by myopia greater than 600 degrees, with growth of the eye axis, retinal and choroidal atrophy and degenerative lesions in the fundus of the eye. High myopia is different from what we generally call myopia, which is an autosomal recessive disease. The main manifestation is the onset of myopia at school or preschool age, and the progressive increase of myopia with age, and the aggravation of retinal chorioretinal lesions in the fundus of the eye, resulting in many serious complications. Therefore, high myopia is also known as pathological myopia, malignant myopia, and genetic myopia. High myopia can cause many complications, the most common and serious of which is retinal detachment. So why is high myopia prone to retinal detachment? This is mainly due to the pathological changes in the eye caused by high myopia. Patients with high myopia have a longer eye axis than normal, which causes the retina in the eye to not receive sufficient nutrition, especially the retina near the periphery often undergoes cystic degeneration, lattice degeneration, etc. The retina in the degeneration area becomes very thin and can easily form a fissure, plus patients with high myopia are prone to vitreous liquefaction Once the retinal fissure is formed, the liquefied vitreous body will enter the subretinal cavity from the fissure, and through gravity, the liquid will gradually accumulate more and more, eventually leading to retinal detachment. If you suddenly feel a black shadow in front of your eyes, and the position of the black shadow is fixed, then you should highly suspect that a “retinal detachment” has occurred. We should go to the hospital for examination as soon as possible, and if the diagnosis is confirmed, surgery should be performed immediately. The later the surgery is, the later the retinal detachment is reset, the more nerve cells will die, and the nerve cells cannot be regenerated, so the worse the vision recovery is after surgery. The choice of surgery for retinal detachment is based on the nature of retinal detachment, the extent of detachment, the size and shape of the fissure, the area of degeneration, whether the retinal surface forms a mechanized film, the degree of vitreous atrophy, and other factors. The purpose of surgery is to close the fissure, eliminate or reduce the traction of the vitreous on the retina, remove the proliferating membrane to free the retina, and finally reset the retina. There are two types of surgery: external surgery and internal surgery. The external surgery mainly includes scleral padding, retinal cryo- or electro-coagulation, intraocular gas injection and ring ligation: it is done by pressing the sclera and choroid with an external padding to make the detached retina adhere to the choroid, and by freezing or electro-coagulation around the retinal fissure to cause an inflammatory reaction to form a scar and then close the fissure. When the fissure is closed, the fluid that has collected under the retina is quickly absorbed and the detached retina is reset. This procedure is mainly used for early stage patients who have peripheral retinal fissures and do not have a total detachment of the retina. Another surgical procedure is the internal surgery, also known as vitrectomy: this procedure is more complex and is mainly used for patients with complex retinal detachment, mechanized membrane on the retinal surface, total retinal detachment, which we call funnel detachment, refractive interstitial clouding, or large fissures in the macula and posterior pole. During the surgery, we remove the cloudy vitreous and release the retinal traction from the vitreous to reposition the detached retina. After the retinal fissure is closed with a laser, a substance called silicone oil is injected into the eye to apply pressure to the detached retina to reposition it. This procedure is complicated, takes a long time, and requires the patient to remain in a strict prone position after surgery, so the patient is in more pain. Therefore, patients with high myopia who have retinal detachment must seek early medical attention and treatment. About 90% of the patients with retinal detachment can be cured with surgery. However, sometimes more than two surgeries are needed to achieve results. If the retina is successfully attached back, the eye will retain some vision and blindness will not occur.