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Why Do I Need My Eyes Dilated?

Why Do I Need My Eyes Dilated?

Eye dilation refers to when the pupil, the black center part of our eye, enlarges or becomes wider. Our eyes naturally dilate throughout the day, depending on lighting and other factors. This dilation and subsequent constriction of the pupil helps us focus and is primarily a safety mechanism that prevents dangerous levels of light from reaching the back of our eye. 

Eye exams can often use drops to dilate the eyes for imaging the retina. It is one of the more uncomfortable parts of visiting the eye doctor, but it can also leave you wondering; If too much light can potentially damage our eyes, why would we want or need to have our eyes dilated?


Why Do I Need My Eyes Dilated?

Eye dilation is often a valuable tool for an optometrist to see through to the retina and optic nerve better. By inducing dilation and using special equipment, they can get a better overall look at your eye's physical condition. A more complete and comprehensive view means they can better diagnose and treat diseases like glaucoma and macular degeneration.

While there are a number of essential examinations that occur without the need to dilate the eyes, testing for diseases like glaucoma are necessary tests that should occur regularly during eye exams. If undiagnosed and untreated, macular degeneration can risk your sight entirely.

How Eye Dilation Works at the Optometrist

Drops are instilled into the eyes which prevent the iris muscles from constricting thus leaving the pupil in a dilated state.  The drops take from 15-30 minutes to achieve maximum dilation.

While dilation eye drops are entirely painless, there are a few noticeable side effects from these eye drops that can last from four to six hours post-exam, including light sensitivity (also called photophobia, and possibly blurred vision.  Most doctors will provide sunglasses for patients who do not have sunglasses after a dilated exam.

If you are going to the optometrist for an exam that utilizes eye dilation, grab a pair of sunglasses to wear afterward, and if you are concerned about driving, try to bring along someone who is willing to drive. 

You should know beforehand if your eye appointment is going to require the use of dilation. And of course, if you have any concerns, always discuss them with your optometrist.

How Often Should a Comprehensive Dilated Eye Exam Occur?

Adults should have an eye exam on a yearly basis.  As we age, the risk of glaucoma, cataracts and macular degeneration increases. Making sure to have a yearly exam can help diagnose and treat conditions before they become too severe for actions to slow damage.  At your examination the doctor will determine if a dilated exam or other types of tests will need to be performed in order to adequately assess your eyes.

Are There Alternative Exams Without Dilation?

If you can’t work around the side effects of dilation or have experienced extreme photophobia or blurred vision caused by the eye drops, don’t use that as an excuse to skip the exam. There are examination techniques that provide your optometrist with a good view of the retina without the use of drops to dilate the eyes. 

One such technique is a new technology called Optomap. It uses a laser ophthalmoscope to scan the back of the retina digitally in a matter of seconds, without dilation. While a regular non-dilated exam might only allow your eye doctor to view about 15% of the retina, Optomap opens the view up to 82% of the eye.  Digital widefield imaging such as Optomap is a clinically equivalent substitute for dilation for many patients.  Some studies have actually shown widefield imaging detects more disease and pathology than just dilated exams.

There is no total replacement for a dilated exam for some conditions of the eye, but for many patients, a non-dilated eye exam is sufficient to catch changes within the eye. Ask your local optometrist if they offer non-dilated eye exam options and if you qualify.

Comprehensive Eye Exams in Asheville

Asheville Vision and Wellness has provided Western North Carolina superior eye care with the latest technology since 1989. Schedule your next annual eye exam with us to see the difference our experience means. We provide an array of medical testing utilizing the best techniques available, including Optomap Ultra-Widefield Retinal Imaging.

If you haven’t had an annual eye exam before, or it has been a while, you can read up on what to expect during your eye exam. We do our best to ensure every examination is customized for you and your unique eye-care needs.