Telescopic Reading Glasses |
PRL for Reading |
With advancing macular
degeneration, the center straight-ahead detail vision reduces. The clarity is no longer there due to “blurry-blind”
spots (scotomas).
NEI Central Scotoma |
Eccentric viewing is particularly
useful when scotomas affect both eyes.
When a person no longer looks directly at the object they want to see,
they are eccentrically viewing (i.e., they are using a healthier part of the
retina). If they look directly at
something, they cannot see it as well as if they look to the side.
With a central blind spot, looking slightly above, below or to one side of the object it can be seen better. The view is not perfect, but better
than if they were looking straight ahead.
For example, someone’s facial features may be better seen by looking
over their shoulder or at their forehead.
"I recognize the body, but not the face" |
Regaining Ability to Perform Everyday Reading Tasks
When reading, patients
report different symptoms. They will say
letters are “missing”, “greyed-out”, “distorted”, “do not make sense” or “they
come and go”.
Reading speed is dramatically
reduced. With advancing disease it is
not uncommon to hear patients say “I read like a first grader”. Eye fatigue and body stress are also common symptoms leading to frustration and exasperation.
Most patients have one
off-center position where they can see the best. The challenges are to find this position and to be able to hold it consistantly
so it can be use most effectively. The position can be practiced while looking at people’s faces, watching television and
reading. For reading it is some times best to practice
with single words.
Ways to Find the Best
Eccentric View Point:
Amsler Grid
Clock Dial
Single Letter or Words
Bat
Steady-Eye Posture Therapy
Once the eccentric viewing
position is determined high-powered glasses (prismatic, telescopic,
or microscopic) are prescribed. The patient views
a word maintaining the eccentric position and the print is slowly moved to the
left so that each word in turn is moved into the best area of vision.
With central scotomas, the patient must continue
to view eccentrically or the glasses will only magnify a blurry image.
Monocular Reading Telescope |
Binocular Reading Telescope |
Experience has shown that
it is best to have the patient sit back comfortably in a chair and bring the
print up to the glasses (to the focal length of the prescription) keeping the
back and neck straight.
Depending on the
size of the scotoma, it is often more challenging to place the reading material
on the table and bend over close to it.
Using a clipboard to support and help stabilize the reading material is beneficial.
Telescope Reading With a Clipboard |
Start with large print initially
to establish consistency. Patience is
the key and the goal is to reduce the font size as reading speed increases. Fluidity is one goal. Reading one-word-at-a-time makes it difficult
to get the context of the sentences.
Returning back to the next
line of print presents another challenge.
One technique is to slide the print back to the right to allow the
patient to quickly scan back along the line of print that has just been read to
the beginning and then move down to the beginning of the next line.
Another technique is to
use a line guide across the sentence that is dropped down when the sentence is
completed.
Experience has also shown
that for some patients the power of the prescribed glasses (i.e., magnification)
may be reduced after adapting Steady-Eye Posture strategies. Reducing the power increases the field of
view and the reading distance.
Powerful Reading Telescope |
Therapy sessions are best in short duration and repeated several times throughout the day.
Length and duration depends on the level of vision loss and the print
size goals.
For effective therapy, prescription
glasses, eccentric viewing techniqes, and patient motivation are critical components.
Call Dr. Kinkade for a free telephone consultation
Cheshire - Danbury - Farmington - Litchfield - Manchester - Norwalk - Waterford
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