strabismus

I'm not sure if anyone can help me here, but I can't seem to find any
info anywhere else. My 7 yr old son had eye surgery 3 wks ago to
correct his strabismus (his eyes were turning in). This is his 2nd
surgery, the 1st one was done about 3 yrs ago. This surgery involved
tightening the muscle on the outside of his eye. The redness has
really faded, but his eyes seem to be overcorrected - they are now
going out. He saw his opthalmologist at 2 wks post surgery, and we
were told it can take up to 8 wks to heal. His eyes never looked this
way after the 1st surgery so I am very concerned. Is there any
exercises he can do to help get his eyes lined up properly? Is this
normal 3wks post-op, or are we looking at another surgery? Thanks for
any input.

 

Tightening surgery is always less predictable than weakening, which is why
the first surgery was to weaken the inner muscles. Part of the reason the
tightening is less predictable is that the muscles stretch out somewhat
after surgery. Therefore, a small overcorrection is reasonable starting out.
It is true the roughly final angle may not be obvious until 6-8 weeks after,
and nothing can be done while you are waiting. Is the the balance of muscle
forces and the reconfiguration of the muscles that determines the final
alignment. Sometimes a lot can happen between the 3 and 6-8 week followups.

Another surgery is not an impossibility, but you have to wait and see. The
standard amount of surgery for the angle is a guide, and different patients
react differently to the same amount of surgery, which unfortunately cannot
be determined in advance.


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

 

David Robins, MD responded:

Dr. Robbins,

A couple of quick questions, if I may:

1) Prism Adaptive Trials?? Since this is surgery #2, perhaps there is more
eso- than "meets the eye."

2) Delayed Adjustable Suturing?? If it wasn't used, perhaps it should be
discussed if, indeed, a third surgery is considered.

3) Would it be important to know whether this child was an infantile
esotrope? If he is not, then isn't it likely that he has developed enough
of a fusion mechanism that vision therapy might be a better approach to take
care of post-op exo- than a third surgery, especially if the residual
exotropia is less than 8-10d? ISTR that vision therapy has a higher success
rate with exo- than esotropia, no?

4) If this child is also a high-plus, it would seem very, very important to
get this exotropia tamed, even if prisms were necessary

Thanks,

Neil

 

Thanks for all the info -
1) what is Prism Adaptive Trials - I'd appreciate any info on this?

2) NO, he did not have delayed adjustable suturing. I just recently
read about it and I would definitely ask about it if he indeed needs a
3rd surgery.

3) I assume by infantile esotrope, you are asking if he had this
problem as an infant. Yes - he was a preemie (3 months early), so
this is actually a common problem. His pediatrician dismissed it,
telling me it was normal for a baby's eyes to turn in. It became very
apparent on photos, which led me to consult a ped opth. He tried
patching and bifocals, which helped somewhat - but still did not
correct the problem. I really wish he would have had treatment before
age 2, but much time was wasted! So at age 3, he had his 1st surgery.
It was successful, that is with his glasses on, his eyes were
straight. 3 yrs later, they started going in again - which leads us
to his present surgery.

4) What is high plus - I really want to do everything possible to
avoid surgery. Is there any place you can direct me to on good vision
therapy? His opth did tell me to do exercises where he needs to
focus on an object and bring it into his nose, so he looks cross-eyed,
and hold it. His right eye always tends to pop right back into that
far off position, he cannot hold it in. Is there any other good
vision exercises he can do?

Thanks so much for your input!

 

PAT testing works when there is some fusion confounding the esotropia
measurements, typically with acquired strabismus, causing undermeasurement
of the angle. This results in too little surgery, and persistent esotropia
after surgery. In this case, the eyes are overreacting to the surgery which
is the opposite.

Can't do it at this young age.

Most adjustable sutures are done once awake, and are limited to cooperative
patients (ie over 13 years old or so), as it is uncomfortable - you are
pulling on the sutures on the eye to adjust the angle in the office, and
then tying it. I make angle measurements like I always do, using prisms
while they look at the eye chart. I use this in almost all adult patients,
not in children.

Some do attempt something like this in kids. They wake them up in the
recovery room and just look at them. Then, the anesthesiologist puts them
back under, in the recovery room, and the angle sutures are changed and/or
tied. Problem is, there are very few OR's where they will allow this to
happen in the recovery room - it is not set up to administer anesthesia.
Also, the angles are not really measured, and it is a guesstimate. Plus, it
is usually done when the child is still very groggy, and this can cause
angle that do not represent what they would be when fully awake. I have
never done this, and I know only a few who have managed to get this by the
regulators.

Fusion exercises work in some cases, but "vision therapy" is not always
that. I myself don't have experience with vision therapy.

If this child is high-plus, glasses would make him look through a base-in
prism, true. However, it sounds like he used to be straighter, and went more
eso, so there is probably little, if any, fusion. In that case, most likely
doesn't much matter what the prismatic effect is.

 

Prisms on eyeglasses are used to see what angle the eyes want to be at in
order to fuse - often a larger angle than the apparent angle seen. Used in
potential fusers. Infantile esotropes have usually no significant fusion,
hence PAT is not used for this.

See y reply to Neil. He is far too young to allow standard adjustable
sutures.

It is common not to get to the steady-state before age 2 with premies - too
much changes going on. You only operate once it is stable, with glasses, and
patching is over. Typical infantile esotropes are stable, and not glasses
dependent, and ready for surgery by as early as 6 months, typically at about
1 year. Premies often are not.

High hyperopia - farsighted. Probably the glasses you have are hyperopic,
but Neil was talking about high powers (ie over 6D or so. When looking
through the lateral part of the lens, this creates a prism effect, adding to
the misalignment of the eyes angled out. Really only an issue of there is
fusion to be gained, not really in infantile eso cases.

Vision therapy I feel has no real use in cases like this, as there is no
eye-to-eye cooperation to begin with. Trying to break down supression and
get both eyes "turned on" at the same time has led to cases of incurable
diplopia, so I would not try. What the opht is trying to do now is get hm to
probably try to stretch those outer muscles that were operated in, in the
hope this lengthens them a bit during the healing period. Can't hurt, but I
can't say what the chance is that it will help, either.

No other exercises I'd recommend. You have to wait and see where the final
result ends up.

 

DANIELLE: I'll respond to your e-mail as well. Again, I'm not a
doctor--just a long-time eye patient who's had three strabismus surgeries
(and a host of other issues that resulted from eye alignment, etc.) myself.
The /medical/ advice has to come from the Dr. Robinses (and others) of this
world and your son's ophthalmologist. I've learned quite a bit on the way,
but . . . a little knowledge can be a dangerous thing. Hopefully, I can
raise some issues that may benefit your son in the long term, but I don't
call the shots. You and your son's doctors do.

Neil0502 wrote:



David Robins, MD wrote:

Thank you. Obviously, we haven't heard the near vs. distant alignment
preoperatively. Assuming it was concomitant, I'm thinking this second
surgery may have overshot, possibly by quite a bit. I was raising the PAT
concept as a way of adding more science to the art. But you're right: it's
after the fact.

Sigh. I get it. Thanks.

Fusion exercises is what I was implying. I was hoping that (if there had
ever been fusion and the residual exo- was low enough) this child could
build his fusional amplitudes and avoid a potential third surgery....

I was also thinking about /reading/. If this child is exotropic post-op,
/and/ is a reasonably high hyperope (I'm thinking +4d or higher), would
there not be a significant additional strain to read (triad of
accommodation)? My point here is that it may be important to get this child
into full plus (again, assuming hyperopia) correction, fusional amplitude
exercises, and possibly prisms (hopefully to be reduced or eliminated on the
success of the fusional work) to reduce the likelihood of further binocular
dysfunction or accommodative issues down the road.

Thoughts??

Thanks, Dr.

 

I'm not sure about the tennis player thing. There are many cues of depth,
binocular fusion being only one of them. Further, vergence is slow
compared to other eye movements, and I'm not sure its fast enough to deal
with a fast tennis ball. There might be some field of view problems, like
a shortened nasal field in the viewing eye, but I'm not sure how important
binocularity is for a tennis pro, at least from the depth perception
standpoint.

Scott

 

I have no fusion and when I was too young to realize this was my situation,
I tried playing tennis and couldn't. In fact, I was partnered with a good
player whose dominant arm was in a cast and she was still better than I was
with my dominant arm. I could not play volleyball either. Though I can see a
ball traveling in the air, I have no idea if it is 5 feet infront of me or
heading 5 feet behind me. So, I took up running, swimming, and biking. I
have become a rather proficient distance swimmer (and have no problems doing
fast flip-turns off the wall probably more from feel of timing than visual
cues)--endurance sports are something I may never have done if I became a
tennis player. One can only wonder how much something like this eye
condition molds us--quite a bit I think, but not necessarily for the worse.

 

(responding to Scott Seidman)

I have no fusion and when I was too young to realize this was my situation,
I tried playing tennis and couldn't. In fact, I was partnered with a good
player whose dominant arm was in a cast and she was still better than I was
with my dominant arm. I could not play volleyball either. Though I can see a
ball traveling in the air, I have no idea if it is 5 feet infront of me or
heading 5 feet behind me. So, I took up running, swimming, and biking. I
have become a rather proficient distance swimmer (and have no problems doing
fast flip-turns off the wall probably more from feel of timing than visual
cues)--endurance sports are something I may never have done if I became a
tennis player. One can only wonder how much something like this eye
condition molds us--quite a bit I think, but not necessarily for the worse.

As a person who also has no fusion and has had three strabismus surgeries, I
was letting Scott slide ;-)

I couldn't agree /more/ with your last statement. My activities of choice:
bicycling, mountain biking, rollerblading, scuba diving, hiking, running,
swimming (see a 'ball' in here yet??), windsurfing (uh, not lately,
but....), etc., etc.

You're absolutely right: throw me a ball and it's going to hit me!
Entertaining for the spectators, but gets old for me. Part of one season as
the water polo goalie in high school proved that pretty well.

Glad you've found your niche. I hope this seven year old boy finds his as
well.

Neil

 

Thanks so much for your concern. My son's prescription is a little
hard to explain. His first ped opth moved out of the area, and I did
not care for the dr who took over. He was recommending surgery again
and changed his prescription to: Spherical-Distance- R +150 L +150,
Cylinder R +50 L +50, Axis R 95 L 88. ADD-R +250 L +250. He wore
these glasses for the next year, however, I didn't want to rush into
another surgery, so the following year I took him to another ped opth
for a 2nd opinion (there are only 2 ped opth in our area). My son
would never look through his bifocal, so the new dr told me he didn't
need them, since he didn't look through them. He got a new
prescription (which, I'm sorry - but I cann't locate at the moment).
We went back in 3 mths to see if his strabismus was improving or
getting worse. My son took his eye test with his glasses on and
totally failed it, he also tended to look over the top of his glasses
a lot because he obviously could not see through them. He took the
test with no glasses and got everything right. So now, the dr decides
he doesn't need any glasses at all, they weren't correcting the
strabismus - it was exactly the same with or without the glasses. He
stressed surgery was the only way to go to get his eyes property
aligned.

So, here we are now, almost 4 wks post-op. My son is not wearing any
glasses at the moment. I won't know the final figures for his
strabismus until his 6 wk post-op appt. Honestly, today is the worst
his eyes have looked. It's making reading and school very difficult,
since he is seeing double. I really hope things start improving for
him in the next 2 wks. Sorry to make this so long, I wish I lived by
San Diego, but I'm not even close, I'm about 4 hrs away from Chicago.
If you can think of any good questions to ask his dr, please let me
know. Thanks! Danielle

 

danielle wrote

 

Actually, reducing the plus migh be used here, using accommodative
convergence to get the exo smaller, but can't reduce the hyperopia by more
than maybe 3 D. I would assume glasses were used before and after surgery,
as is the general rule. Fusional amplitude exercises work is there is
fusion, and from the sound of this case, there probably is no real fusion.
In most cases I've seen, fusion exercises are not of real use. Unless the
angle gets to be small, prisms are also not helpful even if there was
fusion, as large prisms cause too much distortion. In smaller angles, prisms
are of use if there really is fusion, and low fusional amplitudes that
cannot maintain alignment alone. As long as the angle is less than about 12
prism diopters postoperatively, this is in the range for some peripheral
fusion, the only kind of fusion most of these cases have.

 

The Rx is a low plus, which is why the glasses made no difference in the
angle. In a few cases, it can even in this low Rx. Bifocals are only helpful
if the eyes are (almost) straight in the distance, and cross at near, and if
the bifocals then make the eyes straight at near also. If the eyes are
significantly crosses in the distance, even if the bifocals make the
increased near crossing less, it won't make them straight, so they are of
little if any value in that case.

At this point there is really nothing else to do besides wait and see what
happens at the end of the 6 weeks. If he is double, wouldn't hurt to patch
one eye or blur it (frosted scotch tape on the eyeglass) especially in
school. Probably won't influence the angle one way or the other.

 

On 10/28/04 9:27 PM, in article
zEjgd.36382$, "neil0502"

Actually, it is done for high AC/A ratio (accommodative convergence /
accommodation ratio). This is an extremely COMMON problem in kids. That is,
their distance correction makes them straight at far, but they still cross
at near, wearing the full cycloplegic refraction. In most cases, by reducing
the accommodation at near, you can reduce the near crossing and make it
straight by proper choice of bifocal power.

This is different from reading bifocals to read because of near blur due to
poor accommodation, which is what you seem ot be thinking of. True, a 7 year
old should not have a problem focusing at near. But, some do - the
optometrists call it accommodation infacility, or accommodative
insufficiency if worse. Some kids, especially when going thru growth spurts,
seem to have trouble reading, and a lower power reading glasses gets them
through the few months that this seems to take to get back to normal.

 

I still think you'd be surprised by the amount of "normal" people walking
down the street who have poor fusion and never even noticed it.

As a strabismic, though, you're facing some extra problems-- you supress
vision in one eye so as not to see double, so your visual field is
compromised, particularly to the nasal side of your viewing eye. This
might be as damaging to activities, if not more so, than a lack of fusion.

Scott

 

neil0502 wrote:.

Got it. Thank you.

 

On 10/29/04 7:57 AM, in article
tTsgd.2111$, "neil0502"

Prisms can reduce/eliminate diplopia when there is low fusion and small
angle deviation, where diplopia is a problem. If no diplopia, no need for
prism usually.