Occasionally there will be black shadow floating when looking at things usually consider flying mosquitoes, is the physiological vitreous turbidity. Generally this type of vitreous turbidity is mainly related to ageing, and the increase in myopia is related, especially after the age of 45 or highly myopic people. At present, the demand for electronic devices is increasing and people are moving forward in age and prescription, and some people may develop vitreous turbidity in their 30s. Usually this type of condition does not matter because it is also a normal physiological change that does not cause damage to vision and does not produce pain or itching. Clinical observation is the main focus, there is no good way to treat or alleviate the flying mosquitoes, as long as regular follow-up and observation of the fundus can be.