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Understanding the Eye Chart

eyechart

Eye charts of different variations have become a standard in vision screenings and eye exams. One of the most familiar charts associated with vision is the Snellen eye chart, designed by Dutch ophthalmologist Hermann Snellen in 1862 to measure visual acuity- how well you can see at various distances.

Although there are variations of the Snellen chart used today, a traditional Snellen chart has eleven lines of block letters. The first line has one very large letter, which is one of several letters, for example E, H, or N. The following rows have increasing numbers of letters that become smaller in size as you read from the top to the bottom of the chart. The letters used on the chart are C, D, E, F, L, N, O, P, T, and Z.

When taking a vision exam, one eye is covered and you are asked to read the letters of each row aloud beginning at the top of the chart. The smallest row that you can read correctly indicates the visual acuity in the eye being tested.

The chart is positioned at a distance of 20 feet in the United States or 6 meters in the rest of the world. The term 20/20 vision is used to indicate the clarity and sharpness of your vision measured at a distance of 20 feet. If you have 20/20 vision, you can see clearly at 20 feet objects that can normally be seen at that distance. If you have 20/40 vision, it means that you need to be as close as 20 feet to see what a person with normal vision can see at 40 feet. The largest letter on an eye chart often represents an acuity of 20/200 which is associated with the term "legally blind."

You will be asked to read the letters one eye at a time. Some people can see well at a distance, but are unable to bring nearer objects into focus, while others can see items that are close, but cannot see them far away. By having you read the chart, your eye doctor is able to ascertain whether you have difficulty with distance vision and can determine which corrective lenses can be used to improve it. Near vision problems or other vision and eye health issues may not be detected with the Snellen eye chart alone, so a comprehensive eye exam is always recommended.

The next time you hop into the chair at your optometrists' office, you'll be able to understand why you have to read the letters on the chart in front of you and what the results mean for your vision.

Dear Richie Eye Clinic & LASIK Center Family and Friends,

As we head into the Holiday Season and the New Year, I have some news to share.

As many of you know, we have added some new doctors to our team in the last couple of years. Dr. Josh Spedding OD, our new Optometrist, joined us last summer and is currently seeing patients in both our Northfield and Faribault offices. We are thrilled to have Dr. Spedding on our team and welcome him and his family to the area.

Dr. Cory Miller, MD joined us in 2021 and we welcomed Dr. Mike Reinsbach, MD to our team this past summer. Both are Board Certified Ophthalmologists and skilled surgeons specializing in High Technology Cataract Surgery with Advanced Lens Implants, LASIK, Retinal injections, MIGS Surgery for Glaucoma, as well as the usual medical and surgical management of eye disease.

With the addition of these high performing providers, I am transitioning my role in 2023 to concentrate on Practice Development while continuing to serve as the Medical Director overseeing our practice protocols and procedures. Dr. Miller and Dr. Reinsbach will be assuming my day-to-day patient care duties.

I have done my best over the past several months to tell everyone of this transition plan while personally introducing Dr. Miller and Dr. Reinsbach; please accept my apologies if I missed any of you during this time.

Rest assured, we will continue our commitment to providing cutting edge care. Starting in 2023 look for Dropless Cataract Surgery, Light-Adjustable Lens Implants, and so much more…

Thank you for the Trust and Confidence you have shown me over the past 32 years. Please feel free to call us at (507) 332-9900 for questions, concerns, or clarification.

Sincerely,

Mike Richie, MD

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