1, eye resistance decline contact lenses will make the cornea can not contact the air, the eyes will be a lack of oxygen and similar to the human body “plateau reaction” situation, can not be normal metabolism, resistance to decline. 2, resulting in visual fatigue, dry eye syndrome long wearing contact lenses, easy to produce visual fatigue, and even trigger dry eye syndrome. This leads to itchy eyes, foreign body sensation, multiple eye stools, dryness, burning eyes and blurred vision. 3, triggering eye allergies Contact lenses adsorb proteins, lipids, collagen, etc. in tears, which are deposited on the surface of the lens and breed germs, resulting in corneal edema, corneal neovascularization and allergic reactions. 4, wear the cornea, can not receive orthodontic contact lenses wear the cornea, may cause serious consequences of corneal epithelial detachment or perforation. Some contact lens concavity and corneal convexity do not match, irregular wear corneal, causing corneal ulcers, resulting in irreversible vision loss, even after treatment will leave white spots on the cornea. 5, causing ocular nerve paralysis Contact lenses attached to the eye for a long time will paralyze the nerve endings, leading to corneal hyperalgesia. Many patients have ulcerative keratitis and are unaware of it. 6, corneal aging accelerated If you start wearing soft contact lenses from the age of 20, 10 years later, the corneal fef skin cell density equivalent to 60-year-old people, will not be able to withstand any eye surgery, even in old age cataracts occur. 7, myopia deepening, affecting the image