What if my child’s eyes are crossed? Strabismus 411.

HELP! It looks like my child’s eye is turning in, or out or I’m not sure. What do I do? What is strabismus anyway?

Photo courtesy of mjtmail (tiggy) on Flickr

Photo courtesy of mjtmail (tiggy) on Flickr

Strabismus, or crossed eyes, is a condition in which both eyes do not look at the same place at the same time. It occurs when an eye turns in, out, up or down. Strabismus is classified by the direction the eye turns:
• Esotropia = Inward turn
• Exotropia = Outward turn
• Hypertropia = Upward turn
• Hypotropia = Downward turn

There are six muscles attached to each eye that control eye movement. Normally, the eyes work together so both eyes look at the same place at the same time. An eye turn may be visible when there are problems with eye movement control.
The eye turn may be present constantly or only at certain times such as when the person is tired, ill, or has done a lot of reading or close work. One eye or both eyes may alternate turning.

Proper eye alignment is important to avoid seeing double, for good depth perception, and to prevent the development of poor vision in the turned eye.

What causes strabismus?

There are many causes, including:

  • Eye muscle problems.
  • Problems with the nerves that transmit information to the muscles.
  • Trouble with the control center in the brain that directs eye movements.
  • General health conditions or eye injuries.

What are risk factors for developing strabismus?

  • Family history – Those with parents or siblings who have strabismus are more likely to develop it.
  • Refractive error – Especially a large amount of uncorrected farsightedness (hyperopia).
  • Medical conditions – Including Down syndrome, cerebral palsy, stroke or head injury.

How is strabismus diagnosed?
Strabismus is diagnosed through a comprehensive eye exam. Testing may include:

  • Visual acuity, or vision – “Normal” distance visual acuity is 20/20.
  • Refraction – Determine the appropriate lens power needed to compensate for any refractive error (nearsightedness, farsightedness, or astigmatism).
  • Alignment and focusing testing – How well the eyes focus, track, move and work together.
  • Examination of eye health – This includes the front and back of the eyes. Eye pressure is also evaluated.

Because vision may change frequently during the school years, regular eye and vision care is important.

How is strabismus treated?
There are several treatment options to treat strabismus, including:

  • Eyeglasses or contact lenses – For some conditions, glasses alone will align the eyes.
  • Prism lenses – Prisms align the images seen by both eyes, so the eyes can fuse or see the same image, restoring visual clarity and depth perception.
  • Vision therapy – Vision therapy trains the eyes and brain to work together more effectively.
  • Eye muscle surgery – Surgery may be able to physically align the eyes so they appear straight. A vision therapy program may also be needed after surgery.

What can happen if the eye turn is not treated?

Photo courtesy of jmoneyyyyyyy on Flickr

Photo courtesy of jmoneyyyyyyy on Flickr

Potentially an untreated eye turn can lead to amblyopia, otherwise known as lazy eye. Amblyopia is permanently reduced vision in one eye.

When does a child develop strabismus?
Typically strabismus develops in infants and young children by age 3. It may be present in older children and adults. Children do not “outgrow” strabismus.

Most importantly…
If detected and treated early, strabismus can often be corrected with excellent results. Eye examinations are important for all children and adults, starting at 6 months of age. If any eye turn is in question, schedule a comprehensive eye examination immediately.

~Melissa Barnett, OD, FAAO
California Optometric Association
http://www.eyehelp.org
http://www.coavision.org

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Legal blindness – What does it mean?

Recently, after telling a young patient of mine that she needed glasses, she asked “Does that mean I’m blind?” Fortunately, she was nowhere close to being blind. Her vision, with correction, was 20/20 in each eye.

Unfortunately, that is not the case for all of my patients. Some of my patients have lost sight permanently due to macular degeneration, amblyopia, glaucoma, stroke or injuries that have left them with vision much worse than 20/20, even with the best pair of glasses or contacts available to them.

Picture courtesy of musescore on Flickr

Picture courtesy of musescore on Flickr

Although definitions can vary, the term “legally blind” commonly refers to a person who’s vision in their better eye cannot be corrected to 20/200 with correction or who’s visual field is limited to 20 degrees or less.

It is important to delineate the difference between blindness and legal blindness. A person who is blind is unable to see at all; they have no sight. A person who is legally blind is far from being blind. They can see light, and potentially shapes, colors, or even large type. They can still gain visual information of the world around them.

However, people who are legally blind due to vision or visual field do require more assistance than a person with vision that is better than 20/200 or with a visual field larger than 20 degrees. People who have been found to be legally blind can qualify for government assistance programs.

A summary of major federal disability programs can be found here, and the the Department of Human Services list of services for people who are blind or visually impaired can be found here. Californians who would like more information on services available to them will find them in the California Department of Social Services Handbook of Resources and Services For Persons Who Are Visually Impaired. And if you need any additional information, you can always contact your local California Optometric Association optometrist for additional services that may be found in your area.

~Ranjeet Bajwa, OD
California Optometric Association
http://www.eyehelp.org
http://www.coavision.org

Bob Costas’ eyes – An eye doc’s perspective

Screen shot of Bob Costas on air

Screen shot of Bob Costas on air

I’ve been seeing quite a bit of pink eyes these last couple of days. The first one started with Bob Costas’ left eye on TV Friday night while watching the Olympics coverage. The next day, I received two calls on my on-call line from patients worried that they might have a contagious pink eye. I returned to work Monday and have seen more pink eyes in three days than I can remember.

I believe I have Bob Costas to thank for that. Sure, Sage Kotsenburg scored the first gold medal in snowboarding slopestyle, but that wasn’t what my Facebook friends were talking about these last two days. They wanted to know what’s going on with Bob Costas’ eye.

Sadly, I noticed that his infection has spread to the other eye, although the Twitter account @BobCostasEyes probably let slip the 4-1-1 first.

I wish I could definitively diagnose his eye condition. But being that all I have to go on are pixelated images of Bob Costas frozen in mid-speech without the use of microscopes and surface dyes to judge for irregularities, I can only surmise.

If it was a bacterial infection from a contact lens, antibiotics should have cleared it up by now, and it wouldn’t have spread to the other eye.  Now that it’s spread to the right eye, it’s most likely a viral infection.  It looks much worse than it feels. The eyes are usually watery, glassy and bright red. A microscope would show bumps on the inner eyelids as well as any cloudy areas on the surface. This can be treated with medications to limit the length of the infection, although it can last up to three weeks. Cool compresses and artificial tears can provide some relief of symptoms also.

But if you look at Costas’ outer eyelids, they’re also very red and irritated. It’s quite possible that he was given medications that he discovered he was allergic too. In either case, it was smart to finally take a sick day and go off the air to give him time to recuperate. Let’s hope for a speedy recovery before Matt Lauer’s beard has its own Twitter account.

So, to all of you with healthy, white and clear eyes, keep your hands clean and away from your face, don’t shake hands with someone with a pink eye, and see your optometrist if you think you have an irritated pink eye. To read more about pink eye, see our previous blog article on this topic.

~Cindy P. Wang, OD, FAAO

California Optometric Association
http://www.coavision.org

What did my doctor just say? Common terms your eye doctor will use and what they mean

Courtesy of riekhavoc (caughtup?) on Flickr

Courtesy of riekhavoc (caughtup?) on Flickr

Have you ever felt like you were not quite sure what just happened at your optometrist’s office? It is difficult enough to answer the “which is better, one or two?” questions and then at the end of the exam to try and understand the doctor’s explanations with difficult optometry terms without secretly worrying that you might have said something wrong!

Hopefully this blog will help you better understand some of the more common terms we use in our examinations.

1) First of all, most comprehensive exams will include a detailed case history. The doctor will want to know your family medical and ocular (eye) history. Some terms you may hear include the most common eye diseases – cataracts, glaucoma and macular degeneration.

  • Cataract is the term used when the natural lens of your eye becomes cloudy, causing blurred and distorted vision.
  • Glaucoma is the eye disease that causes your eye to have excessively high pressure, which can lead to long-term damage of the nerve in the eye.
  • Macular degeneration is a disease that affects your central or straight ahead vision.

Not only will the optometrist ask you about a family history of any of these conditions, they will also assess your eye health and your possible risk for developing any of them.

2) Next, the optometrist will perform a refraction to get you the best possible glasses or contacts that will correct your vision.

  • A refraction is just the process of determining for each individual what are the best lenses to give you maximum visual clarity and comfort at both distance and near.
  • Myopia – nearsightedness or the ability to see better at near than at far.
  • Hyperopia or farsightedness, really means that it is more difficult to focus at near and at far distances.
  • Astigmatism: this refers to the shape of the front surface of the eye being more football shaped rather than basketball shaped.

3) There are a few terms you might hear specifically in an child’s exam.

  • Pursuits: slow, smooth eye tracking.
  • Saccades: fast reading eye tracking.
  • Accommodation: focusing.
  • Binocularity: the ability of the eyes to work together as a team.

4) Finally, there are some terms regarding glasses that it might help to define.

  • Progressive lenses are the kind of “no line bifocal” that you might hear about on TV. But, unlike a bifocal, where there are two areas of vision, near and far, progressives have an unlimited amount of areas as you look from distance to near in the lens.
  • Transition lenses are the kind that change to dark outside. They undergo an anti-reflective treatment, which eliminates all glare and allows for crisper vision, especially at night.

Hopefully, this quick explanation helps with some of the confusing terms in an eye exam. As for any others, always ask your optometrist to explain something that does not make sense.

~Lisa Weiss, OD, MEd, FCOVD
California Optometric Association
http://www.coavision.org