Targeting plano in the dominant eye and –1.25 D to –1.

5 D in the nondominant eye will yield high-grade

intermediate and near vision. does not reduce stereopsis significantly. Patients who enjoy playing tennis, for
example, do not complain of inability to function on the court. Postop patients typically can be measured to
have high-grade stereo acuity.
•does not reduce contrast sensitivity significantly. While some reduction in high spatial frequency contrast
sensitivity occurs during distant tasks in the nondominant eye, the patient can compensate. The brain
"shifts" its attention during these tasks to the dominant eye, which has perfect contrast sensitivity. You won't
find "perfect" contrast sensitivity in an eye with a multifocal.

How does monovision work?

Typically, a lens set to far distances is implanted in your dominant eye, while a lens set to near distances is
implanted in your non-dominant eye. While it may sound strange to deliberately make the two eyes have
different focusing powers, the two eyes actually can work together well to provide clear, blended vision at all
distances.
Monovision works because your brain automatically adjusts your visual system to achieve clear vision when
you are focusing on near and distant objects.
When you focus with your “near eye” on near objects:
•Your brain partially suppresses vision in the distance eye
•This suppression helps the near eye take in the full stereo picture
When you focus with your “distance eye” on distant objects:
•Your brain partially suppresses vision in the near eye
•This suppression helps the distance eye take in the full stereo picture
Am I a good candidate for IOL monovision?
You may be a good candidate for IOL monovision if you:
•Desire high-quality vision at all ranges (near, distance and intermediate) without glasses or contact lenses
•Cannot wear or don’t like bifocals
•Cannot wear or don’t like contact lenses
•Love outdoor activities and sports for which wearing glasses is inconvenient
You are not a good candidate for IOL monovision if you:
•Have a history of eye muscle surgery, double vision or prism in your glasses
•Need perfect, fine stereovision for your job, such as flying an aircraft
•Cannot pass pre-operative monovision screening tests
•Have significant astigmatism and are not interested in having it corrected (there is an extra out-of-pocket
cost that is not covered by insurance)
•Have a history of severe eye problems in the past, one eye or both eyes, such as lazy eye,
severe glaucoma with significant loss of peripheral field vision, severe diabetic retinopathyor severe macular
degeneration with multiple medication injections into your affected eyeball(s)
•Have a history of stroke with severe side vision loss, history of Parkinson’s disease or history of severe
Graves Eye Disease (thyroid-related eye disease)
Before your cataract procedure
Before your cataract procedure, we will conduct a careful preoperative personal consult about your lifestyle,
job and hobbies, and perform a series of tests and eye measurements to determine if you are a good
candidate for monovision.
If you are a good candidate for IOL monovision:
•We will select appropriate intraocular lenses with different powers to correct one eye for distance and the
other eye for near vision.
•If you have significant astigmatism, you will likely need to have your astigmatism corrected during your
cataract surgery – otherwise you may still need to wear your glasses for most of your daily activities.
•With laser-assisted cataract surgery, the monovision technique can be expected to be more precise.
After your procedure
•You can be expected to be glasses free for most of your daily activities due to increased focus depth with
good vision for far, intermediate and near.
•However, you may still need a pair of glasses for backup, such as for nighttime driving or reading small print
for a few hours or more.
•You may experience some mildly compromised fine depth perception in certain specialized tasks, such as
threading a needle, which may require reading glasses.
•But you should not expect to have a problem for daily activities that require stereovision, such as navigating
curbs, stairs and steps.
•If you decide you no longer want monovision, you can simply reverse the effects by wearing glasses. The
need to have implant exchange is extremely rare
 Two years ago, Anne Collins of Arlington, Va., who has been wearing glasses since fifth grade, noticed she
had trouble reading the overhead street signs while driving. Cataracts, the clouding of the natural lenses that
occur with age, were taking their toll.
She decided it was time for cataract surgery.
Mrs. Collins, now 61, chose to have her lenses replaced with two different intraocular lenses – one for
seeing far and the other for seeing near — in a procedure known as monovision cataract surgery.
“I thought it was a miracle,” Mrs. Collins said after the surgery was completed. “It was like I was back in
second grade and didn’t have any problems with my eyes.” Still, her vision isn’t perfect. Mrs. Collins still
needs glasses to read the newspaper, but she can see her cellphone just fine.
By age 80, more than half of all Americans either have a cataract or will have had cataract surgery,
according to the National Eye Institute. The average age for the surgery is the early 70s.
Cataracts typically develop in both eyes, and each eye is done as a separate procedure, usually one to eight
weeks apart. Patients most commonly have their clouded lenses replaced with artificial monofocal lenses
that enable them to see things far away. Most will still need glasses for reading and other close-up tasks.
With monovision surgery, the patient’s dominant eye receives a replacement lens for distance vision. In a
subsequent operation, the less dominant eye receives a lens for close vision. Once surgery on both eyes is
completed, the brain adjusts the input from each eye and patients typically can see both far and near. Some
people can stop wearing glasses altogether, although many, like Mrs. Collins, still need them for certain
tasks.
But monovison takes some getting used to. The ideal candidates may be people who already have tried a
monovision approach with contact lenses for 15 or 20 years, before they even have developed cataracts,
said Dr. Alan Sugar, a professor of ophthalmology at the University of Michigan. “People who have worn
contact lenses in their 40s, with one contact for near vision and one for distance, are good candidates,” he
said.
Others may be able to give monovision a trial run. The cataract surgeon replaces the first eye with a lens
that corrects for distance vision and then, if the cataract in the second eye hasn’t progressed too far, can let
the patient use a contact lens for near vision in the second eye, Dr. Sugar said. If the patient is comfortable
with the trial monovision, the surgeon can then implant a lens for near vision in the second eye.
Experts caution that monovision surgery is not for everyone. “Many patients get misled by asking how their
friends like monovision,” said Dr. David F. Chang, a clinical professor of ophthalmology at the University of
California, San Francisco, and past president of the American Society of Cataract and Refractive Surgery.
“Some individuals hate what another individual loves.”
After any cataract surgery, including monovision surgery, patients may also experience what doctors call
“dysphotopsia,” or visual disturbances like seeing glare, halos, streaks or shadows. Moderate to severe
problems occur in less than 5 percent of patients, said Dr. Tal Raviv, an associate clinical professor of
ophthalmology at the New York Eye & Ear Infirmary of Mount Sinai Icahn School of Medicine. Symptoms
often improve during the first three months after surgery without treatment, he said, though in a small
number of cases one or both lenses may need to be replaced.
In addition, some patients who get monovision surgery will need a separate pair of glasses that focus both
eyes for distance vision for driving at night. “Night driving is more difficult if both eyes are not optimally
focused at distance,” Dr. Chang said.
Some visual functions such as stereopsis, contrast sensitivity, and visual fields can decrease after
monovision correction.[2] Pseudophakic monovision has the same problems as monovision induced by
Lasik, CK and contact lenses, especially when there is high postoperative anisometropia.
When targeting monovision, the nondominant eye is usually targeted for near and the dominant eye for
distance. However, some patients are able to have the reverse, he said.

I'm right eye dominant for distance.

Extend both hands forward of your body and place the hands together making a small triangle
(approximately 1/2 to 3/4 inch per side) between your thumbs and the first knuckle
•With both eyes open, look through the triangle and center something such as a doorknob in the triangle.
•Close your left eye. If the object remains in view, you are right eye dominant. If closing your right eye keeps
the object in view, you are left eye dominant.
Evaluating Your Eye Dominance
1. 1
Try a simple pointing test. With both eyes open, point your finger at a distant object. Close one eye,
then switch and close the other eye. Your finger should appear to move off or away from the object
when one eye is closed. If the finger does not appear to move, then the eye you closed is your
nondominant eye.[1]
• Another variation of this test is to stretch your arms out in front of you and form a triangular-shaped
hole with your fingers. Look through this hole at an object about 10 feet (3 m) away, keeping both eyes
open. Without moving, close one eye, then the other. The object should appear to move, possibly out
 of the triangular window, when you close one of your eyes. If it moves, then you are looking through
your nondominant eye.

2.
2
Conduct the Distance-Hole-In-The-Card test. This test examines which eye you use to focus on
objects that are 10 feet away. You can easily perform it on yourself at home.[2]
• Cut a hole in a piece of paper that is about an inch and a half in diameter. On a second piece of paper
write a single letter so that it is roughly one inch high.
• Tape or tack the paper with the letter onto a wall at eye level. Measure a distance of exactly 10 feet
away.
• Stand 10 feet away from the letter on the wall. Hold the paper with the hole in it at arm’s length with
both hands. Your arms should be parallel to the floor.
• Look through the hole in the paper at the letter in the wall. When you can see the letter, have a friend
cover first one eye, then the other. Don’t move or adjust your position. The eye that can see the letter
is your dominant eye. If you can see it with both eyes, then neither eye is dominant in this task.
3.
3
Do the Near-Hole-In-The-Card test. This test is similar to the distance test, but it examines which eye
you use when focusing up close. You can also do it with quickly and easily with household objects.[3]
• This test can be done using a thimble, shot glass, or similar household object. Write a single letter on a
piece of paper so that it is about 1/16th of an inch tall and wide. Tape this letter to the bottom of the
inside of the thimble or shot glass.
• Cover the thimble or shot glass with paper or aluminum foil. Fix it in place with a rubber band or tape.
Make a small hole that is about 1/16th of an inch in the paper or foil. The hole should be over the letter
so that you can see the letter when looking through the hole.
• Put the thimble or shot glass on a table and lean over so that you can read the letter. Do not touch the
thimble/shot glass or press your eye to the opening. Your head should be about 1 to 2 feet away.
• Don’t move your head while you look at the letter. Have a friend cover one eye, then the other. The
eye that can see the letter is your dominant eye. If you can see the letter with both eyes when the
other is covered, you don’t have a dominant eye for this test.
4.
4
Do the convergence test. This test examines which eye is dominant at extremely close distances.
The results may differ from the results on the other tests.[4]
• Get a ruler. Write a single letter on a piece of paper. The letter should be about 1/16th of an inch high
and wide. Tape the letter to the ruler so that it doesn’t move.
• Hold the ruler out in front of you with both hands. The letter should be at eye level. Focus on the letter.
Slowly, with both hands, move the ruler straight towards your nose.
• Stop moving when one eye is no longer able to focus on the letter. That is the nondominant eye in this
task. If both eyes remain focused until the ruler touches your nose, then neither eye is dominant in this
task.