Flying mosquitoes are generally thought to be caused by vitreous opacities. The manifestation is the appearance of intermittent dark shadows floating in front of the eyes, some are transparent, some may be in the form of stripes, filaments or clouds, most patients may be related to vitreous liquefaction, or posterior vitreous detachment. If you find that after the appearance of mosquitoes in front of the eyes, it is best to go to the hospital ophthalmology in time to do dilated fundus examination. Especially with high myopia, or eye trauma after the patient, is a high risk group. If there are also obvious symptoms of flashing, it means that the retina receives the vitreous traction and reacts, and needs to be seen as soon as possible, mainly to exclude pathological vitreous turbidity. Because the detached vitreous may tug on the retina, sometimes leading to the rupture of blood vessels and the formation of retinal fissures and retinal detachment, a detailed examination of the fundus should be done as soon as abnormalities are detected. If, after detailed examination, no abnormality is found in the fundus, but only simple vitreous clouding, it can be considered without treatment and given observation. At present, there is no effective drug treatment for simple vitreous turbidity. For the age of 45 years old or above, there are obvious posterior vitreous detachment weiss ring type of vitreous cord clouding, can also be treated by modern vitreous ablation laser, while minor vitreous clouding, do not need to be treated by laser ablation. So if there is flying mosquitoes after, it is best to choose the hospital ophthalmology consultation.