Mobile Devices & Double Vision

Within the past 5 years (from 4/9/2016), there have been reports in the eye care field showing that excessive smartphone use (“excessive” being defined as more than 4 – 6 hours per day) causes a condition called esotropia (crossed eyes) which results in double vision. 

My office is beginning to see young adults who fit this category.

A little background history is helpful here. One hundred years ago, developmental optometry came to the conclusion that our eyes were designed for distance activities, like searching for food or watching out for predators.  When we used our eyes for close work, it was usually for a 3-dimensional task such as using or making tools, or cooking and eating. 

Our daily tasks involved shifting our vision from far to near to far again. This was a very healthy way of using our visual system.

When reading became a popular activity in the 1920s, optometrists began to notice how reading produced headaches and eyestrain in some of their patients, and how many good readers became nearsighted (losing their ability to see clearly at far distances).

Developmental optometry analyzed the task of reading and found these 6 detrimental factors:

1. Social – economic pressure to maintain the task.
2. Restricted area of eye movement involved.  (No shifting of eyes from far to near to far, a close and fixed working distance of 10-13 inches.)
3. High contrast. (Dark letters on white background). 
4. Two-dimensional (a flat page).
5. Prolonged concentration required.
6. All body movements inhibited.

This abnormal situation produced changes in the ways our eyes functioned and led to visual problems and/or symptoms.

Fast forward 100 years to 2021:  Today’s children, young adults, and adults are placing themselves in a similar abnormal situation when they use their smartphones at a close distance of 8 or 9 inches from their face.

Seeing double is very disturbing. Walking becomes more challenging, and driving becomes exceedingly dangerous.

For patients who are seeing double, Dr. Gushiken has developed a 5  pronged approach which represents the first step in helping patients recover their normal binocular (seeing clear and single) vision.

STEP ONE:

1. We explain how incorrect posture (close working distance) and excessive screen time may cause double vision.
   
   
2. We recommend taking multiple breaks: go outdoors, walk, move, stretch, look at various objects that are far away.
   
   
3. We advise that you increase the distance that you hold your phone while in use to your “Harmon distance” (the distance from your closed fist middle knuckle to your elbow). You can also switch to using your iPad/tablet or laptop, which can be used at farther working distances.
   
   
4. We recommend wearing near-point, stress-relieving lenses when using your phone and other screen devices. Your developmental optometrist can write you a prescription for these glasses. These glasses can be worn over your contacts. (Note: These lenses are different than blue light blocking glasses.)
   
   If you are nearsighted, wearing a “minimal prescription lens” or “removing your glasses” is often beneficial. However, if you remove your glasses and find yourself holding your phone closer than 6 inches in order to see the content, you should ask your optometrist for an appropriate prescription that will allow you to see your phone at a farther distance.
   
   
5. We encourage practicing the “Cover, Uncover, Recover” vision therapy activity twice a day, 4-5 times a week. (This activity is described below.)

Return to your optometrist in 3 months to see if your double vision has improved. “Improvement” means that either you no longer see double, or it occurs so infrequently that it doesn’t bother you.

STEP TWO:

For those patients who did Step One for 3 months and continue to experience double vision, we would then recommend an in-office vision therapy program.

STEP THREE:

If a patient wants to try a different approach, a referral to an ophthalmologist can be made for extraocular muscle surgery. However, our office does feel that this type of surgery should be considered “a last resort.”

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COVER,  UNCOVER,  RECOVER

Purpose: To improve your eye coordination. This skill will help keep your eyes straight and provide you with good depth perception.

Materials: A variety of targets that are located in the distance.

For example:

• T.V. across the room or laptop on desk
• Clock on wall 
• Air conditioner on wall
• Framed picture on wall
• Looking at your own reflection in hallway mirror

Time: 10 to 15 minutes, twice a day. Four to five times a week for 3 months.

Procedure (with a TV as example target):

1. Stand about 4 to 6 feet from the TV.  If you see two TV images at that distance, slowly walk towards the TV until it comes into focus as one. (If you cannot see one TV at any distance, please contact our office.)
   
   
2. As you look at the TV, cover your right eye with your right cupped hand. Avoid touching or pressing on your eye; simply place your hand in front of your eye. Keep your eye covered for about 3 to 5 seconds.
   
   
3. Next, quickly uncover your right eye and attempt to point your eyes so that you see one TV image.
   
   If you see two TV images slide into one, that means that your right eye made an outward movement to link itself up with your left eye. This is your goal.
   
   If you see two TV images, try blinking your eyes until the two TV images slide into one. You can also walk toward the TV – so that you are closer to the TV. This closer distance from the target will make it easier to obtain one image.
   
   
4. Repeat the above 20 times.
   
   For example, you could say to yourself:    
   “Cover, uncover, recover, one.”
   “Cover, uncover, recover, two.”
   “Cover, uncover, recover, three.”
   And so on…
   
   
5. When you’ve completed the above, repeat the same steps by covering your left eye with your left cupped hand. Repeat this 20 times.
   
   
6. Finally, repeat the above by alternately covering your right eye, then your left eye, then your right eye, etc. Repeat this 40 times.
   
   
7. Now take one, two, or more steps backward, while seeing one TV. Try to find the distance where you begin to start seeing double. Then move a little closer to where you can see one, then do the cover, uncover, recover steps.
   
   
8. On subsequent days, change your target and attempt to increase the distance that you are standing from the target. Take notes on which targets are easy to keep as one image and which are hard. (“Hard” being defined as: the target is always double.)
   
   
9. Your goal is to immediately see one target at a 15 to 20 feet distance when you uncover your eye. The target should be clear, not blurry.

If you are experiencing double vision and/or have any questions regarding the above approach, please contact our office to schedule an appointment.