20/20 Vision, What Does That Even Mean?

ery time you go to the eye doctor one of the first things they do is check your visual acuity. Your visual acuity is the sharpness of letters or images at a fixed distance according to a fixed standard.

Let’s break it down in terms that are easier to understand.

We all have heard the term 20/20 but what exactly does it mean.

According to the Snellen chart, 20/20 is the standard for normal vision. The Snellen chart is used in the United States by eye doctors, (optometrists and ophthalmologists), as well as other doctors. There is no such thing as perfect vision. (The only person that has perfect vision is Superman.)

The Snellen chart was developed by Herman Snellen, a Dutch Ophthalmologist, in 1862. The chart is based off of a distance of 20 feet and lines of letters that are a specific size with the largest one on top, gradually getting smaller at the bottom. According to the Snellen chart, 20/20 means you have normal vision at a distance of 20 feet.

This picture might clear that up.

Patient A has 20/70 vision so they are only able to read line 3 on the Snellen chart at 20 feet away. Patient B who has 20/20 vision can read the same line at 70 feet away.

Here is a video that also explains it. What is 20/20 Vision?

Stop by for your FREE visual acuity screening Tuesday - Friday from 10am - 6pm.

Text us to schedule your next complete eye exam 801-987-8698.

Vision Therapy: Making Your Eyes Work For You

Do you have either of these eye conditions?

• Lazy eye (amblyopia)

• Crossed-eyes (strabismus)

When you're reading do any of these things happen?

• You often lose your place

• Words go in and out of focus

• You struggle retaining what you’ve read

If you answered yes to any of these questions you could benefit from vision therapy. Vision Therapy is a customized treatment to improve and strengthen a person's vision and how your eyes work together and with your brain. Most often vision therapy is done with children but anyone who has any of the above mentioned issues may be able to improve their vision and ability to read by one of many custom treatment plans. Vision therapy is designed to treat the vision problems that glasses alone can’t fix. These are some Vision Therapy techniques:

• Eye tracking using computer games. This uses your eyes as the mouse to accomplish tasks in computer games. This may sound simple but it is actually very effective in getting your eyes working together and it’s fun.

• A Marsden ball is used to focus on something finite and add movement while maintaining focus on the same thing. Our Marsden ball hangs from our ceiling and is white with letters randomly all over it.

• Stereo viewers are used to find depth. Both eyes have to be working together to see the 3D image. Many eye doctors will do a stereo test on children as part of their routine eye exam.

• Life saver cards are clear cards that have green circles that look like lifesavers on one side and red circles on the other side. Together the circles make a V shape. These cards are designed to get the eyes working as a team to see a phantom circle in between the 2 circles.

There are many other techniques that are used in vision therapy; these are just a few. The keys to making vision therapy work for you are: working with an Optometrist trained in vision therapy, following the plan, repetition, and consistency.

You're Going To Do WHAT To My Eyes???? Part 3

Dilating your eye causes the pupil to get bigger so the doctor can better check the Macula and optic nerve health. The picture below shows it best.

To properly dilate your eyes the doctor will put eye drops in your eyes. It can take 15-30 minutes for your pupils to fully dilate. Dilated eyes can last for 4-6 hours on average, though for some people it can last longer. (BrightFocus Foundation brightfocus.org)

How often should I get my eyes dilated?

It is recommended for children and people 40+ to get their eyes dilated every year. People with underlying health conditions such as diabetes and hypertension should also be dilated every year. Everyone else should be dilated every other year. If you're not sure if you should be dilated check with your eye doctor and they will let you know.