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Tips to Prepare for a Dilated Eye Exam

With over two decades of experience in medicine, Melissa Flagg writes patient education articles, keeping you informed about your health.

After your vision has been checked and the refraction completed, the technician will check your pressure and then dilate your eyes. Dilation is an integral part of any eye exam, especially for those with systemic diseases such as diabetes or ocular diseases such as macular degeneration.

About the Author

Melissa Flagg is an ophthalmic technician and has been examining patients on a daily basis for over 19 years.

She has had rigorous training under the supervision of an ophthalmologist and specialized in the cornea, cataracts, and retina as well as how systemic disease affects the eye. She has been certified by JCAHPO as a Certified Ophthalmic Assistant.

Checking the Intraocular Pressure

The intraocular pressure check is a quick test, but a vital one. The procedure involves the technician anesthetizing the eye with a yellow dye and anesthetic combination drop known as fluorescein (pronounced floor-a-seen). This drop does sting when instilled until the anesthetic takes over and numbs the eye.

It is important to blink or bat your eyes as quickly as you can. This distributes the drop and allows the anesthetic to numb the eye more quickly than if you were to squeeze the eye shut. It will also ensure the eye is sufficiently numb for the tonometer probe. It is difficult to do since the drop stings quite a bit, and the natural reaction is to shut the eyes. It’s mind over matter here, but it can be done.

A Tonometer

The Tonometer used to check the intraocular pressure.

The Tonometer used to check the intraocular pressure.

The Mires of a Tonometer

These are the mires seen by the technician as they check your pressure.

These are the mires seen by the technician as they check your pressure.

A Note About The Pressure Check

If you go to your ophthalmologist specifically for a foreign body sensation, or sensation of something in the eye, DO NOT let the technician check your pressure if they attempt to do so.

An eye with a potential abrasion should be looked at first, and any technician worth his weight will check the cornea before attempting to check the pressure.

After the yellow dye, the technician will align you in the slit lamp. Technicians who are new to the field, will just go straight to the pressure check, using the blue-lit tonometer probe (see photo).

However, technicians who have been doing this for eons will always check your eye first to make sure the cornea is clear. This is important to make sure there is nothing on the cornea that will affect the reading or make it unsafe to use the tonometer, such as a corneal abrasion or scratch.

The technician should also check the angles of the anterior chamber (the space between the cornea and iris - see drawing below) to make sure it is safe to dilate your eyes.

They will then move the tonometer in place, turn on the blue light and have you look at a specific spot. They may or may not hold your lids. It’s more accurate if you do not hold a patient’s eye open during applanation because there is no risk of putting pressure on the globe (eyeball) which would artificially create a high pressure reading.

I rarely had to hold my patients’ eyelids open, but I was also quicker than the majority of technicians I worked with. Sometimes, however, you have no choice.

The easiest way for you, the patient, to hold your eye open for this test is to tap your fingers on your leg and to concentrate on doing so while the technician checks your pressure. It’s tough to do, but it will distract your brain from what’s happening to your eye, making it easier for you to keep your eye open. Whatever you do, don't squeeze your eye shut as this will artificially increase your pressure.

A Drop Used for Dilation

Cyclopentolate is typically used to dilate patients for cycloplegic refractions and prior to LASIK procedures.

Cyclopentolate is typically used to dilate patients for cycloplegic refractions and prior to LASIK procedures.

Dilating the Eyes

After the pressure check, your technician will instill dilating drops into both eyes and then have you sit in a waiting area while your eyes dilate.

This can take anywhere from 10 to 30 minutes. Those with dark irises will take longer to dilate and may need several applications of the dilating drop.

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Keeping your eyes closed will speed up the process. This forces your eye to dilate allowing the drops to penetrate the iris muscle faster.

Seeing the Ophthalmologist

Once you are dilated, you’ll be taken to see the doctor. He will examine the eye with a slit lamp like the one the tech used to check your pressure. He will also use a small magnifying lens to look at the optic nerve.

This little lens can cause the light of the slit lamp to be very bright, which can be painful and cause your eye to water. Try your best to keep your eye open; this part of the exam will be over more quickly if you are able to keep from blinking or moving your eye.

Image of the Retina

An image of the retina as seen by the ophthalmologist during an exam.

An image of the retina as seen by the ophthalmologist during an exam.

You may hear the doctor rattle off some medical lingo to his assistant. This is what he sees in the eye as he examines it. He calls out the information to the scribe (assistant) for him or her to record in the chart. It will typically sound something like this:

"Cornea clear, anterior chamber deep and quiet, lens two plus NS, cup to disc ratio .5."

Don’t be alarmed by this. This is only the doctor describing the anatomy of the eye to the scribe.

After the slit lamp exam, the doctor will put a device on his head that I like to call the space helmet. It’s actually called an indirect ophthalmoscope, but it looks almost alien. It has a light on it and mirrors that magnify so the doctor can view the retina clearly.

Your doctor will use a larger lens this time for magnification and this will cause the light to be very bright. If you can’t handle it, let the doctor know. He can turn the light down a bit, but he needs it to view the retina properly. It’s best to grin and bear it, and try to keep your eye open.

Eyes that have been dilated. Note the large pupils.

Eyes that have been dilated. Note the large pupils.

He will ask you to look in eight different directions: up and right, up, up and left, left, down and left, down, down and right, right and then finally straight ahead. This is so he can view all the peripheral areas of the retina.

Sometimes the doctor will use an instrument called a scleral depressor to push the walls of the globe in to see the most peripheral areas of the retina. This can be very uncomfortable, but it is usually only done when there is the possibility of a retinal detachment. The doctor will let you know prior to performing scleral depression so you’ll know it is coming.

I’ve only seen a general ophthalmologist perform this a couple times. Once was on myself because I asked him to do it. (I’m a glutton for punishment.) It is typically only done by retinal specialists.

After this examination, the doctor will make a few notes, and then address your eye health with you. This whole procedure only takes about three minutes. With managed care insurance plans the way they are today, it is difficult for the doctor to spend more than five minutes with a patient. But if you have questions, you need to ask them. Most good doctors will ask you if you have any questions before he tells you when he would like to see you again and excuses himself.

A Few Things to Keep in Mind

If you aren’t satisfied that the doctor has answered your questions, it’s important to voice your concerns. Ask your questions before the doctor leaves the room so that you do not have to ask to see him again before you leave. Unfortunately, this tends to irritate doctors because it throws off their schedule, and they may take that out on you, the patient.

But you are entitled to answers to your questions. If you happen to think of a question after you’ve seen the doctor, ask to speak with the most experienced technician. Doctor’s don’t always explain things in layman’s terms, but technicians have much more experience in this area.

I would also like to mention wait times. I know how frustrating it is to wait in a doctor’s office. I’ve waited for four hours before. But as a medical professional, I also understand why this happens.

The technicians and doctors can only work as fast as their patients will let them. Patients who have medical complaints that require unforeseen, additional testing take longer, and when appointments are scheduled, no one knows what tests will need to be done.

If you are getting frustrated by waiting, try to remember that your wait just means the staff is taking the time each patient needs and will do the same for you when you are finally called back. Getting impatient and becoming irate will only make the staff want to get you out of the building as quickly as possible and you won’t get the care you need. You catch more flies with sugar than with vinegar.

© Copyright 2012 by Daughter of Maat ALL RIGHTS RESERVED


Mel Flagg COA OSC (author) from Rural Central Florida on August 10, 2013:

Thank you jaydawg!

jaydawg808 on August 09, 2013:

Very informational, thank you!

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