Brandon's Amblyopia Treatment: Help!

OK,
Now I've got more information on my son's extreme farsightedness after a
second visit to the optimetrist. He is the 5 1/2 year old who I described
in a couple of earlier posts.

Before his corrected acuity was 20/200 (20/500 without lense) in the
weak/Amblyopic eye with +8.00 lense and 20/40 in the good eye (not sure if
that was with or without lense). Today with the +4.00/+2.125 he was 20/200
and 20/25, respectively. The doctor did not want to change the prescription
for fear of double vision developing, and because even corrected his acuity
is poor. She did not retest his acuity level with +8.0 lense. The eye
exercise she prescribed was 1 hour daily for six weeks, and to do active
work during that 1 hour rather than just patching. She advised the use of
scotch tape over the lense rather than a patch. She said they were a part
of active vision treatment programs, but none were aimed at Amblyopia
victims at this time, but Birmingham may offer such.

Questions: Is 1 hour sufficient or should we do more? What is the risk of
really developing double vision? Should we wait six weeks to get the
correct lense? She advised we could get stronger lense if we went contact
lenses immediately, but wanted to see his acuity improve before prescribing
different glasses. Is his prescription likely to change in 6 or more weeks?
Advice, in general?

Thanks,
A very concerned father.

Jeff

 

1. If you test an amblyope's vision using a lens that is 4 diopters
underplussed, these eyes accommodate poorly and will often measure lower
acuity than what they really are with best corrected lenses. I would not
expect much vision improvement until he is wearing glasses that more closely
correct the error in the amblyopic eye, due to the image remaining out of
focus during treatment.

2. If he was seeing, I would do maximum occlusion therapy. Scotch tape over
the better eye still allows in light, which interferes with the amblyopic
eye trying to see, and slows treatment. (This is a dictum of Dr. Arthur
Jampolsky, world-famous strabismologist, who, by the way, actually used to
be an optometrist in his previous life.) I would put him in the full Rx, and
use patch occlusion for most of his awake hours. Note that while he is
patching, double vision due to the unequal Rx, if you believe in it, cannot
happen, since only one eye is being used during the patching. Once he
attained maximum improvement, then the issues of glasses full Rx vs. contact
lens can be brought into play. Children generally do not develop double
vision at this age, especially in the face of dense anisometropic hyperopic
amblyopia.

3. What is the reference to Birmingham?

4. No, the eyeglass (cycloplegic) power of his eyes is not expected to
change hardly in 6 weeks. By the way, with high hyperopia such as this, I
generally don't fully trust my office cycloplegic eyedrops, and usually do
an "atropine refraction", using atropine 1% ointment at home once a day for
3 days, unless they have very light color eyes where office drops are
sufficient.

Is the prescribed power from the optometrist likely to change in 6 weeks?
That I don't know.

THIS IS MY OPINION!

David Robins, MD
Board certified Ophthalmologist
Pediatric and strabismus subspecialty
Member of AAPOS
(American Academy of Pediatric Ophthalmology and Strabismus)

____________________________________________

 

Questions: Is 1 hour sufficient or should we do more? What is the risk of
really developing double vision? Should we wait six weeks to get the
correct lense? She advised we could get stronger lense if we went contact
lenses immediately, but wanted to see his acuity improve before prescribing
different glasses. Is his prescription likely to change in 6 or more weeks?
Advice, in general?[/QUOTE]

First of all, I don't know much about amblyopia or farsightedness. I have
experience with double vision due to wearing glasses with unequal
correction.

About 10 years ago (I am now 53) I was diagnosed with cataract in both
eyes. It wasn't bad enough to justify surgery, but the doctor said that
it almost always gets worse, and I would probably need surgery in 5-10
years. He gave me a whole lot of options (which have nothing to do with
your son), and finally he said that based on my choices (which he thought
were good and usual), I would need to switch from glasses to contacts or I
would probably see double. So I switched primarily to contacts, but wore
glasses when I felt like it. In a few years I had the surgery in one eye,
and got a new lens for my glasses. I came home, took out my contacts and
put on the glasses. Then I sat outside and watched the cars go by. There
was one car driving along the street like they are supposed to, and an
identical car driving along about 10 feet in the air! It was pretty
amusing. So, when I wore contacts I saw normally, but when I wore glasses
with the same prescription I saw double. I was not surprised, since both
my OD and my OMD had explained this to me many times. Although I wore my
contacts every day, 7 days a week, for 12-14 hours, I wore these glasses
for the time after I took out my contacts and before I went to bed. I
eventually learned to suppress my vision in one eye, so I didn't see
double. This was OK for me, because I only did this for a couple of hours
a day, and I had almost 50 years of experience with seeing with both
eyes. Of course, this is exactly what your son has learned to do, to
suppress the vision in one eye, and what you are trying to stop.

After five years of this, I had surgery in the other eye, and have plano
vision in both eyes. I now have the option of wearing glasses again, but
so far haven't. I don't know about the timing, but if the doctor is
pushing contacts over glasses, you should listen. I always thought that
contacts were something that only vain people wore, but I was wrong. For
people who need minor correction and roughly the same amount in each eye,
then contacts might be cosmetic. But for people who need a lot of
correction (and +8 is a lot) or have unequal amounts of correction (and +8
and +4 are pretty unequal), contacts will significantly improve vision. I
sure wish that I had gotten contacts earlier. It's a hassle to learn to
wear them, but it's going to be easier for a younger person to get used to
them.

 

1. Different situation entirely. Post cataract surgery is induced
anisometropia with equal length eyeballs, due to lenticular refractive
difference. You cannot equate that to the axial anisometropia of a child's
eyes. Axial differences do better with eyeglass lens correction than contact
lens correction, up to an ill-defined limit, due to an optical principle
called Knapp's Rule.

2. Child's amblyopia (suppression) is not due him wearing unequal glasses
and trying to suppress an image as you did, as you suggest. It is due to the
more farsighted eye staying out of focus, not sending a sharp image to the
brain, which therefore never learns to "se" a sharp image.

3. There is NO NEED for contacts in any case until you establish that the
amblyopia is treatable, and is finished treating it by occlusion therapy, as
only 1 eye will be used most of the time, so the inequality issues are moot.
Once binocular vision is desired, then one can argue over the issues above
about Knapp's Rule, etc.


I would suggest that your lay input is sending him off on the wrong track,
but it makes interesting reading...


David Robins, MD
Board certified Ophthalmologist
Pediatric and strabismus subspecialty
Member of AAPOS
(American Academy of Pediatric Ophthalmology and Strabismus)



On 10/21/03 12:57 PM, in article
, "Dan Abel" <>
wrote:

see

 

The differential issue is in adults with qual length eyes. Yes, then once
you get above about 1.5 difference, size diplopia can occur. However, you
are forgetting most of this kids have axial length differences, and your
inequality of images is not what you suggest. As I've mentioned, David
Guyton, MD, one of the optics gurus of all time, has stated many times that
by Knapp's Rule, unequal eyeglass lenses reduce the diplopia issue in axial
anisometropia, and is aggravated by contact lenses.

So, I think the optometrist in question is not "absolutely right" in
children. Adults with postop cataract asymmetry, I would totally agree, but
not here.

Also, maximum patching should always include tiem for vision in the other
eye, in any case. As long as the eyes are straight, simply removing the
patch for a minimum of 1 hour per day will give enough visual stimulation.
If strabismic, some woul argue to put the patch on the amblyopic eye for 1
hour per day, instead. I've always just removed the patch for the hour, with
or without strabismus, while in the process of treating the amblyopia. The
faster is gets ove, the sooner one can get back to using both eyes.

I agree than the +8D may drop slowly, as is commonly seen. The other eye
increasing is much less commonly seen, but can happen. However, unless the
difference is corrected when in glasses, the amblyopic eye will remain, or
go back to, the amblyopia. Instead, once the amblyopia is over, and you've
been using about full power to optimize the focus and less the amblopia get
treated, then you can order glasses with equal reduction each eye. Ie, if it
is now +8 and +4, once the treatment is over I'd probably cut each by 1.5,
to +6.5 and +2.5. This stimulation of equal accommodation both eyes is
probably what drives gradual reduction in the hyperopia.


David Robins, MD
Board certified Ophthalmologist
Pediatric and strabismus subspecialty
Member of AAPOS
(American Academy of Pediatric Ophthalmology and Strabismus)

___________________________________________

 

I didn't think I knew much about amblyopia. You've just shown me that I
know even less than I thought!

I think I was missing that distinction. I realized that his condition
wasn't due to unequal glasses, but wasn't thinking about the difference in
the situation.

Oh, well. This is a learning experience for me anyway. I certainly hope
that no one is going to do anything not recommended by their doctor based
on what I post here.