You look in the mirror and notice that the dark circles in the middle of your are bigger than usual. What\’s going on? Those dark circles are your pupils, the openings that let light enter your eye so you can see. Muscles in the colored part of your, called the iris, control your pupil size. Your pupils get bigger or smaller, depending on the amount of light around you. In low light, your pupils open up, or dilate, to let in more light. When itвs bright, they get smaller, or constrict, to let in less light. Sometimes your pupils can dilate without any change in the light. The medical term for it is mydriasis. Medicines, injuries, and diseases can all cause this eye condition. A few medicines can affect the muscles that control your pupils and prevent them from getting smaller when light shines in. These meds include:
(Atropen), which treats problems with rhythm, issues, and some types of poisoning, like diphenhydramine, like and anti- medicines such as Parkinson\’s medications such as ( ) and -levodopa ( like amitriptyline ( ) and ( (, Myobloc) Anti- drugs, such as ( ) and topiramate ( Dilated pupils are one sign that someone has used, such as: These drugs affect the muscle that widens the pupil, slowing how it reacts to light.
So even in a bright room, the stay dilated. Withdrawal from these drugs can also make the pupils stay open wide. Pressure that builds inside your after a head injury, or tumor can damage the muscles in your iris that normally make your pupils open and close. One or both of your pupils can become fixed in the dilated position and canвt react to light. If that happens, you should see a doctor right away. If you\’ve had a, your doctor or nurse might shine a light into your during the exam to see if your pupils get smaller. When a doctor physically examines your eyes, they are looking not just at the outer surface, but at the inside health of the eye too.
They do this by looking through the pupil, which is like a keyhole into the \’room\’ where the retina is. When the light shines into the eye, the pupil naturally shrinks smaller to protect the eye from what it perceives to be bright sunlight. By putting special eye drops into the eye, the doctor can make the pupil open wide, just as it does when we enter a darkened room. The doctor can see much more clearly to examine our inner eye through this wide opening, making the examination far more effective and thorough. Although having the pupils dilated is a time-consuming inconvenience, it is a necessary part of your preventative eyecare. Application of the Eye Drops As part of a regular eye examination the optometrist will apply eye drops into your eye to dilate and open the pupils.
The take approximately 15-20 minutes to work. Side affects of this drop is sensitivity to light and difficulty focusing up close, such as reading a book, for a few hours. For this reason you should allow plenty of time for the examination itself, for both the preparation time and the recovery time afterwards. Dilating drops work on one of two principles: they either stimulate the iris muscle that opens the pupil (the dilator), or prevent action of the iris muscle that closes the pupil (the sphincter). What Does the Optometrist See? Once the pupil is fully dilated, which takes around thirty minutes after the eyedrops have been applied, the optometrist can then see all the way into the back of the eye. During a normal eye examination, the doctor uses a light and a lens to look right into the eye and inspect the health of the cornea, the iris and the lens of the eye.
They can check the optic nerve and the important blood vessels to make sure there are no signs of disease or cataract. Pupil dilation can also reveal other health problems such as hypertension (high blood pressure), diabetes, eye conditions like and cataracts. Dilated exams can also detect thinning areas of the retina, or tears and holes which can lead to a retinal detachment and blindness. Once the eye examination has been completed, the pupils will remain dilated for a while, so it is a good idea to wear to protect your eyes from the bright daylight which may hurt your eyes. Some supply disposable sunglasses if you have forgotten to bring any. Having your eyes dilated may make you feel slightly disoriented for a while afterwards. You should sit for awhile before driving, or take someone with you to drive you home. To Summarize Eye Dilation: Related Questions