What is dilation and why do you need it?

What does dilation do?

Most patients' vision at distance does not change from being dilated. 

Dilation relaxes your accommodative muscles in the iris so that your pupil opens up, it's just like opening the window so that your doctor can see all the structures in the back of the eye. 

However, if you are farsighted and your focusing system tends to over engage even for your distance vision it is possible to have your prescription kind of come out a little bit when you're dilated. 

There are patients who have difficulty seeing at a distance when they are dilated. But for the most part, most patients are able to drive themselves. 

Dilating Eye Drops 

• Paralyze muscle that makes pupil smaller
• stimulate muscle that makes iris (colored part of eye widen)
• keep pupil from adjusting to focus (accomodation)

Dilating eye drops may be used for reasons other than eye exams. For instance, your ophthalmologist will need to dilate your eyes to perform some types of eye surgery.In some cases drops will be used after surgery as well to keep your pupil wide. So scar tissue wont form. Sometimes your eyes may be dilated to relax your lenses muscles so your eye doctor can measure properly for your glasses prescription. Eyedoctorsmayuse dilating drops on children who have amblyopia or lazy eye.  

Side Effects of dilation

The side effect for the patient is that your focusing system will be temporarily out of commission. For most patients that's going to affect them closely only for about 4 to 6 hours, it's just difficult to see up close for reading and computer. 

Other than being fuzzy up close for about 4 to 6 hours there are some other side effects of being dilated. 

You will notice that you're much more light-sensitive than normal. If you're very light-eyed whether that's green or blue dilation tends to affect you maybe a little bit on the longer side. If you have very dark irises dark-brown for instance it tends to affect you quite as long. Your dilation should go away if standard dilation drops are used within about 4 to 6 hours. 

There are instances where stronger dilation drops are used and your optometrist will let you know that your dilation is expected to last closer to 12 or 24 or longer hours.