In the ophthalmology clinic, every time you dilate the pupil of a patient, you will meet the patient’s confused eyes, why do you dilate my pupil, why do you dilate my child’s pupil, will dilating the pupil cause damage to the eyes, why do I have trouble seeing for a while after dilating the pupil? Let me answer your questions now. First of all, let’s understand what kind of structure the pupil is. The pupil is a small hole located in the center of the iris in the central part of the eyeball, if the eye is compared to a camera, then the pupil is the aperture of the camera, it is said that the eye is the window of the soul, then the pupil is the window on the piece of bright glass. Pupil shrinkage and expansion of the decision to enter the eyes of the amount of light, the daytime light when the pupil will be narrowed, the night light when the pupil will be dilated when the pupil will be scattered, in the shock and pain and other stimuli when the pupil will also be dilated. The pupil will shrink during sleep, and some eye diseases can also cause changes in the pupil, such as acute angle-closure glaucoma, the pupil will be dilated, and the pupil will be narrowed or even atretic during acute iridocyclitis. At the same time, the pupil is also one of the important vital signs for us to observe systemic and ocular diseases. Generally speaking, ophthalmologists use medication to dilate the pupil for two purposes, one is to check for disease and the other is to treat the disease, the most common of which is to check the fundus and optometry. When the pupil is dilated, some of the conditions in the back part of the eye can be seen at a glance, which is conducive to the doctor’s diagnosis and treatment of diseases in the back part of the eye, such as laser, cataract, vitreous and retinal surgery. For children and adolescents, the most common practice is to dilate the pupils before optometry, because children and adolescents have strong eye adjustment ability, without dilating the pupils in the case of optometry, in myopia will lead to high test results, in hyperopia will lead to low results. A few days ago, a ten-year-old girl, before the pupil dilation check for 400 degrees of myopia, after the pupil dilation of only 50 degrees left, if not dilated on the prescription, live a “artificial myopia” appeared. Think about it! There are many kinds of dilating drugs, the doctor will make appropriate choices according to the use and the age of the patient, before dilating the pupil will routinely measure the patient’s intraocular pressure, grasp the indications, exclude contraindications, generally within three years of age, we will choose the atropine ophthalmic ointment, half a month or so the pupil is restored, from 4 years old to 11 years old will choose the SafeJet, one to two days or so to restore the children over 12 years of age will choose the Tropicamide, 5 hours to restore. When dispensing eye drops, the patient’s tear ducts will be compressed to promote absorption of the drops in the eyes and to reduce the side effects of the medication. To order the dilated medicine, dot the medicine between the lower eyelid and the white part of the eye. Close both eyes gently. The doctor examines the fundus of the patient’s eye after dilating the pupil. Patients will have short-term blurred vision and some fear of light during outdoor activities after their pupils are dilated, which are normal phenomena and will soon return to normal without much concern and will not cause adverse effects on the eyes and the body. Speaking of which, are you still afraid of dilated pupils?