Both eye and general examinations are required before cataract surgery. Eye examination includes visual function examination, including visual acuity, distance vision, near vision, and light localization examination in nine directions, color vision examination, laser interferometry, contrast sensitivity, flash retinal electrogram, visual evoked potentials, etc., and flushing of tear ducts and removal of dacryocystitis. Pupillary examination such as pupil size, reaction to light, etc. Slit lamp examination of the degree of lens clouding, site, there is no subluxation, as well as the cornea, aqueous humor, iris, etc. There is no abnormality. Fundoscopic examination to rule out retinal optic neuropathy, eye A ultrasound, eye B ultrasound examination, to clarify the length of the eye axis and to rule out retinal detachment and other diseases. Systemic examination includes blood pressure, chest X-ray, electrocardiogram, blood test, coagulation time, liver and kidney function, blood sugar and other tests.