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Snellen Chart

Hopefully by now, we’ve all seen one. The projected or wall-mounted Snellen eye chart, usually topped by the big letter “E”, is a common visual acuity test used to measure your sharpness of vision at multiple distances.

Arranged as a pyramid of sorts, the letters in the Snellen chart are specifically chosen and arranged to test your sharpness and clarity of vision at a baseline distance of 20 feet. During a visual acuity test, the Snellen eye chart is viewed as a projection, or mounted on a wall.

Handheld versions of Snellen charts are used for testing near vision as well.

By viewing or reading each line from top to bottom (with one eye covered at a time), your eye doctor can gain a general approximation of the quality of your visual acuity, or sharpness. Where a line of characters begin to become difficult to see is the approximate measurement of your vision.

The Snellen chart serves as a beginning—not an end—to a comprehensive eye examination.

What does “20/20” vision mean?

Snellen charts help to determine a baseline for your vision in each eye—a baseline typically measured against “20/20” vision. This means when you are 20 feet away from an object, you can comfortably see details that most people with normal vision can also see at 20 feet distance.

If you have 20/30 vision, that means what you see comfortably at 20 feet, can be seen by a person with “normal” vision at 30 feet. Your vision is weaker, in other words.

Conversely? In the rare instances where vision may test better than normal on a Snellen chart, a value of 20/10 vision means that you can see clearly from a distance of 20 feet, what a person with normal vision sees well at a distance of 10 feet. Make sense?

In fact, if you look closely at a Snellen eye chart, you’ll see the vision values associated with measuring your vision on the right or left side of each line of characters.

 

Special thanks to the EyeGlass Guide, for informational material that aided in the creation of this website. Visit the EyeGlass Guide today!

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Most people between the ages of 40-45 start to have difficulty seeing up close. This is called Presbyopia and slowly progresses until about the age of 65. This is a normal change due to the lens in the eye hardening and losing flexibility.

Vuity is 1.25% pilocarpine. This is not a new drug. It has been on the market for decades and is used to temporarily shrink the pupil size. It is now being rebranded as a drop that can help improve near vision. How does this work? By shrinking the pupil size, physics tells us this can increase our depth of focus. This drop will not CURE presbyopia. It can improve it while the drop is active and the near blur will return when the dose wears off after approximately 4-6 hours. This drop is recommended for individuals ages 40-55.

Dosage: one drop in each eye once per day. Side effects: possible brown ache or a mild headache. The cost at this time is about $80-90 per month at most pharmacies and insurance does not apply.