What is 20/20 – a perfect vision for 2020

A Dutch ophthalmologist, Dr. Herman Snellen, developed the 20/20 measurement system for visual acuity in 1862. Could he even have dreamed that 158 years later optometrists all over the US would be doing a happy dance that the year 2020 is going to be their year.

What is 20/20 vision?

In the Snellen measurement system- the top number represents the distance between the person and the eye chart. In the US, this distance is 20 feet. At this distance, one of the smaller lines at the bottom of the eye chart has been declared the standard- to correspond with normal visual acuity. If you can identify the letters on this line, but none of the smaller letters on lower lines, you have 20/20 vision.

The letters get larger as the lines go toward the top of the chart and each line corresponds to worse visual acuity. The smaller letters in lines below the 20/20 line correspond to better than 20/20 visual acuity. If you can read the 20/10 line- your visual acuity is two times better than someone who can only read the 20/20 line.

snellen chart
20/20 vision
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optometrist
Example of a Snellen chart

The single “E” at the top of the chart represents 20/200 vision. If this is the smallest letter you can read WITH corrective lenses in front of your eyes, you are legally blind.

Why do you keep saying 20/20 visual acuity?

While we tend to say “20/20 vision” a more proper term is 20/20 visual acuity. Vision is a term that is too general to accurately describe what the 20/20 measurement denotes. Why? Well, 20/20 vision is measured statically for one- in other words while the person is not moving. Also the measurement is using high contract- black letters on white background. This measurement is useful for a relative comparison of clarity of vision in a standard situation. It is a poor indicator of a person’s ability to see colored objects, moving objects or depth perception- all qualities of one’s vision. A more comprehensive description of vision would include eye tracking ability, contrast sensitivity and focusing speed.

An optometrist measures visual acuity with an instrument called phoropter in a procedure called a refraction. You’ll remember this from the eye exam when the doctor asks which is better one or two? and moves knobs or buttons until you can read the 20/20 line. The resulting numbers represent the strength of lenses needed to help you see 20/20.

patient getting eyes checked
2020 vision
eye exam
phoropter
Dr. McEathron measuring visual acuity

The quest for perfect vision

As discussed above, 20/20 visual acuity is a measured by eye doctors. There are even smart phone apps that can measure visual acuity. Using this reference will catch most visual disorders such as farsightedness, nearsightedness and astigmatism. Unfortunately certain eye conditions will prevent correction to 20/20 even with corrective lenses in glasses. These conditions include cataracts, macular degeneration and even extreme dry eyes. Often these conditions are progressive- meaning the vision degenerates more and more over time. There can be preventative measures to slow and even stop progression but in some cases the vision deterioration is irreversible. Read more information here about proactive eye care. Annual eye exams are extremely important to evaluate eye health and look for any early signs of these damaging conditions. An comprehensive eye exam is much more than seeing if you can read the 20/20 line. Every time you write “2020” let that be a reminder to visit the optometrist and congratulate them on the year of perfect vision. Click here to schedule your appointment today!

Much of the information in this blog post was gleaned from Dr. McEathron, Dr. LeClaire and the fine writing at www.allaboutvision.com.

Slow down “birthday induced changes” – part 3

Have you considered what it would be like to lose your sight?

A recent article in US News and World Report discusses a nationwide survey showing vision loss to be equal to or worse than losing hearing, memory, speech or a limb.  How about you?  Is age-related vision changes and loss a concern?  Have you considered what it would be like to lose your sight?  Are you taking steps today that could reduce risks of vision loss or blindness tomorrow?

See clearly – check yearly!

regular maintenance, routine eye exam, binyon vision center, bellingham eye careHow often do you take your car to be serviced or head to the dentist?  How often do you update the anti-virus software on your PC to protect your hard drive?

A routine eye check-up can monitor your eye health – catch problems before they start and keep your eyes in top working condition.  There is a lot more to a comprehensive eye exam than “which is better one or two”?

“I don’t need my eyes checked – I can see just fine!”

A patient came to see us for his first routine eye exam at the age of 55.  He had just started to wear over the counter readers but never had any vision problems.  During the visual fields test, Dr. McEathron discovered a field loss in his vision.  The glaucoma pressure test and assessment of the optic nerve confirmed a likely diagnosis of glaucoma.  The patient immediately began treatment for moderately severe glaucoma.  The 10 degrees of near vision field loss seen will never be recovered – the daily prescriptions drops the patient takes will slow progress of the disease, but as of now there is no cure.  Another important note to mention- the patient had no family history of glaucoma.

Fit an eye exam into your schedule

Eye exams are recommended every year.  The affordable health care act has deemed pediatric vision one of ten essential health benefits.  Many insurance plans include coverage for a routine eye exam yearly.  For more information on what your insurance plan covers, call our office and we can provide you with details.

In the beginningregular maintenance, routine eye exam, binyon vision center, bellingham eye care of the year- your birthday month – as soon as school’s out for summer or before the year is out – pick a time to schedule your yearly eye check up/regular preventative maintenance and stick to it!  Your future self will thank you!

Slow down “birthday induced changes” – part 2

Since today is Dr. McEathron’s birthday- it’s appropriate to communicate more of his tips to slow down age-related vision changes in your eyes.

Eat healthy now – see long term benefits!

Choosing to eat healthy can have a long term impact on your eye health and therefore your age-related vision changes. And, the good news is it certainly goes beyond carrots. Antioxidants and other specific vitamins nutrients can reduce your risk of cataracts, macular degeneration and glaucoma.  Furthermore, omega-3 essential fatty acids also help alleviate dry eyes and guards against macular damage.

Here are the main vitamins and nutrients that help protect our eyes:
  • Lutein
  • Zeaxanthin
  • Vitamin C
  • Vitamin E
  • Essential fatty acids
  • Zinc
  • Beta carotene
  • Bioflavanoids
Food sources that have high content of the above nutrients:
  • Carrots
  • Sweet potatoes
  • Squash
  • Kale
  • Spinach
  • Blueberries
  • Cherries
  • Legumes
  • Salmon
  • Walnuts
  • Eggs
  • Milk
  • Oysters
  • Beef
For an extra boost – vitamins!

In addition to food sources, there are many supplements on the market that promote eye health and help prevent age-related vision changes.  For example, for individuals at higher risk of eye disease, especially with family history of macular degeneration or glaucoma, Dr. McEathron certainly recommends adding an eye health supplement to your daily routine.  There are many such supplements on the market. However, the supplement should provide at minimum the following for maximum effectiveness as a result:

  • vitamin C (250 to 500 mg)
  • vitamin E (400 IU)
  • zinc (25 to 40 mg)
  • copper (2 mg)
  • vitamin B complex that also contains 400 mcg of folic acid
  • omega-3 fatty acids (2,000 mg)

Finally, after researching and evaluating several brands of eye health vitamins, we chose to offer Biosyntrx to our patients at our office.  Furthermore, they have three formulations:

  • BioTears – support for dry eyes, is also rich in omega 6 essential fatty acids.
  • Eye and Body Complete – includes a broad spectrum of 43 ingredients that consequently eliminates the need for an additional general multi-vitamin supplement.
  • Oculair – rich in vitamins, minerals and antioxidants, specifically targeting eye health but also with whole body benefits.

In conclusion, taking care of your eyes and entire body now through proper nutrition will give substantial benefits as each birthday passes as a result!  Stay tuned for more tips on how to beat those age-related vision changes!

Slow down “birthday induced changes” – part 1

Happy Birthday to you…

Dr. McEathron often talks to patients about how to slow down age-related vision changes to their vision and eyes.  It’s his gentle way of bringing up the inevitable- along with the rest of our body- our eyes change as we age.  This blog post is part one of a discussion on how to slow down those birthday induced changes to your eye health and vision.

Here comes the sun…

There is much talk about protecting your skin from the sun- wearing sunscreen daily and link between UV exposure and skin cancer- but let’s talk about your eyes.  The tissue on and around our eyes is thinner and more sensitive than the rest of our body.  Eyes can sunburn with a great amount of sun exposure in a short time. This effect is called photokeratitis and can be very painful.  Symptoms can include watery eyes, burning and feeling like grit is in your eyes.  Thankfully it is typically short-lived (up to one week) and usually has no long term effects.

Long term UV exposure to our eyes can however have long term effects, including on our age-related vision changes. UV-A and UV-B light rays speed up the process of forming a cataract and increases the risk of macular degeneration.  Both of these conditions affect your vision – cataracts make the world seem cloudy and blurry- which cannot be corrected with glasses, only surgery.  Macular degeneration is a loss of the central vision- a blind spot that is irreversible.  As previously mentioned- the skin around the eyes and tissue on the eyes is very thin. Consequently, excessive sun exposure without proper protection can lead to skin cancer and premature signs of aging, therefore furthering age-related vision changes.

Sunglasses protect your eyes today and tomorrow!

sunglasses to help with age-related vision changesWhenever you spend time outside, there are easy ways to protect your eyes from the sun to help reduce the risks discussed above.  Wearing quality sunglasses that provide 100% protection against UV-A and UV-B radiation is the first step.  Transition lenses (that darken in sunlight) also provide 100% UV protection.  Wrap-around sunglasses provide the most amount of protection.  Don’t forget about protecting children and young adults eyes too!  They typically spend the most time in the sun. Therefore, implementing the sunglasses habit can make the biggest impact to their long term eye health. It does this by reducing the amount of accumulative hours of UV exposure!

See Cleary – Check Yearly

 

In addition to sun protection- yearly eye exams to monitor eye health in all of these risk areas are very important.  If you have any questions or concerns- please contact us for an appointment today or stop in to talk with one of our opticians about sunwear!