Deficient binocular fusion ?

Dear All,
I would like to ask you about my case. I've had strabismus onset
(esotropia) when I was 1yr old. It was sucessfuly corrected at age 5.
Althought I'm virtually stereoblind, I was able to keep my eyes
straight most of the time, and strabismus wasn't a problem for me.
Unfortunately after I had started proffessional career as a software
developer, it became worse, and I underwent second surgery for
alternating exotropia few months ago.
But what really is haunting me is my sensory status. Almost whole life
I've been told that I dont have binocular fusion or event
"simultaneous perception" - year after year, my eye doctor used to do
me a test with synoptophore, with the same result: images were
separated and when I tried to join them one disappeared. So she said
that I dont have a binocular vision.
Before my second surgery I went to another doctor, I was pessimistic
when she sat me in front of synoptophore, but then... first of the
time I was able to fuse images! I don't have an idea why it worked.
After surgery I'm still able to fuse images when synpoptophore is set
on +13 deegres eso angle. Besides chiasopic free space fusion cards
works as well. Stereopsis is totally absent.
Sorry for this rather boring introduction. I just wanted to draw some
background. So...can someone explain me why fusion can be obtained
with this eso angle ? My eyes look cosmetically straight, so why
synoptophore gives this angle ? And I even before recent surgery it
was like that, despite of I had 20 degree alternating exotropia! I've
read that strabismus might recurr when binocular vision is impaired
and eye doctor said that it is probable that I will need more surgery
after 3-5 years, but after all - how I was able to keep eyes straight
for such long time without binocularity ? I'm able to swithch fixating
eye or look with both... does not it mean that I'm "binocular" to some
extent ?
Best regards
Jack

In article
<92135c8f-77d7-418b-aebb-(E-Mail Removed)>,
jac-k <(E-Mail Removed)> wrote:

> Dear All,
> I would like to ask you about my case. I've had strabismus onset
> (esotropia) when I was 1yr old. It was sucessfuly corrected at age 5.
> Althought I'm virtually stereoblind, I was able to keep my eyes
> straight most of the time, and strabismus wasn't a problem for me.
> Unfortunately after I had started proffessional career as a software
> developer, it became worse, and I underwent second surgery for
> alternating exotropia few months ago.
> But what really is haunting me is my sensory status. Almost whole life
> I've been told that I dont have binocular fusion or event
> "simultaneous perception" - year after year, my eye doctor used to do
> me a test with synoptophore, with the same result: images were
> separated and when I tried to join them one disappeared. So she said
> that I dont have a binocular vision.
> Before my second surgery I went to another doctor, I was pessimistic
> when she sat me in front of synoptophore, but then... first of the
> time I was able to fuse images! I don't have an idea why it worked.

Maybe, after all this time, your brain figured out how to do it?

When I needed cataract surgery, I was given some choices. One of those
choices, that I picked, was that I would probably see double when
wearing glasses. So I just made sure (at the doctor's urging) that I
could wear contacts with no problem. So I wore contacts 14 hours a day,
7 days a week, after my surgery (this was before they had contacts for
continuous wear). This worked fine. However, I didn't want to wait
until it was time to go to bed to take out my contacts, so I took them
out a couple of hours before. I did see double, but it didn't bother me
much, and my brain learned to adapt, like yours, by blocking out the
image from one eye.

--
Dan Abel
Petaluma, California USA
(E-Mail Removed)

On Nov 9, 1:53*pm, Dan Abel <da...@sonic.net> wrote:
> In article
> <92135c8f-77d7-418b-aebb-be18789f4...@t2g2000yqn.googlegroups.com>,
>
>
>
> *jac-k <jac...@gmail.com> wrote:
> > Dear All,
> > I would like to ask you about my case. I've had strabismus onset
> > (esotropia) when I was 1yr old. It was sucessfuly corrected at age 5.
> > Althought I'm virtually stereoblind, I was able to keep my eyes
> > straight most of the time, and strabismus wasn't a problem for me.
> > Unfortunately after I had started proffessional career as a software
> > developer, it became worse, and I underwent second surgery for
> > alternating exotropia few months ago.
> > But what really is haunting me is my sensory status. Almost whole life
> > I've been told that I dont have binocular fusion or event
> > "simultaneous perception" - year after year, my eye doctor used to do
> > me a test with synoptophore, with the same result: images were
> > separated and when I tried to join them one disappeared. So she said
> > that I dont have a binocular vision.
> > Before my second surgery I went to another doctor, I was pessimistic
> > when she sat me in front of synoptophore, but then... first of the
> > time I was able to fuse images! I don't have an idea why it worked.
>
> Maybe, after all this time, your brain figured out how to do it?
>
> When I needed cataract surgery, I was given some choices. *One of those
> choices, that I picked, was that I would probably see double when
> wearing glasses. *So I just made sure (at the doctor's urging) that I
> could wear contacts with no problem. *So I wore contacts 14 hours a day,
> 7 days a week, after my surgery (this was before they had contacts for
> continuous wear). *This worked fine. *However, I didn't want to wait
> until it was time to go to bed to take out my contacts, so I took them
> out a couple of hours before. *I did see double, but it didn't bother me
> much, and my brain learned to adapt, like yours, by blocking out the
> image from one eye.

I'm not a doctor, but AM A true "congenital esotrope."

I actually think Dan's got the right idea.

In the time during which you were a baby, and an uncorrected eso, the
fusion center in your BRAIN tried its darnedest to put the two images
together, and create stereopsis.

Any idea what (how many diopters) your pre-(first) operative deviation
WAS??

It would also seem that -- like mine -- you didn't develop your fusion
mechanism (brain) properly, meaning ... it's quite possible that
mechanical straightening of your eyes will ONLY be a temporary fix.

Best of luck!

On Nov 9, 2:54*pm, jac-k <jac...@gmail.com> wrote:
> Dear All,
> I would like to ask you about my case. I've had strabismus onset
> (esotropia) when I was 1yr old. It was sucessfuly corrected at age 5.
> Althought I'm virtually stereoblind, I was able to keep my eyes
> straight most of the time, and strabismus wasn't a problem for me.
> Unfortunately after I had started proffessional career as a software
> developer, it became worse, and I underwent second surgery for
> alternating exotropia few months ago.
> But what really is haunting me is my sensory status. Almost whole life
> I've been told that I dont have binocular fusion or event
> "simultaneous perception" - year after year, my eye doctor used to do
> me a test with synoptophore, with the same result: images were
> separated and when I tried to join them one disappeared. So she said
> that I dont have a binocular vision.
> Before my second surgery I went to another doctor, I was pessimistic
> when she sat me in front of synoptophore, but then... first of the
> time I was able to fuse images! I don't have an idea why it worked.
> After surgery I'm still able to fuse images when synpoptophore is set
> on +13 deegres eso angle. Besides chiasopic free space fusion cards
> works as well. Stereopsis is totally absent.
> Sorry for this rather boring introduction. I just wanted to draw some
> background. So...can someone explain me why fusion can be obtained
> with this eso angle ? My eyes look cosmetically straight, so why
> synoptophore gives this angle ? And I even before recent surgery it
> was like that, despite of I had 20 degree alternating exotropia! I've
> read that strabismus might recurr when binocular vision is impaired
> and eye doctor said that it is probable that I will need more surgery
> after 3-5 years, but after all - how I was able to keep eyes straight
> for such long time without binocularity ? I'm able to swithch fixating
> eye or look with both... does not it mean that I'm "binocular" to some
> extent ?
> Best regards
> Jack

Jack asked:
"So...can someone explain me why fusion can be obtained
with this eso angle ? My eyes look cosmetically straight, so why
synoptophore gives this angle ?"

Strabismus isn't cosmetically noticable until about 15 to 20 prism
dioptres of deviation. Fusion after surgery is often weird and
wonderful.

You likely have anomolous correspondence, your eyes can achieve fusion
when the image separation corresponds to the original, pre surgery
deviation of the eyes. Every point on the retina of one eye
corresponds to a point on the retina of the other eye, with both
points having the same perceived location in space. The two points
will be fused by the brain to create one image.

The wiring that underlies fusion was laid down in the first year of
life based on the original deviation. Surgery alters where the eyes
point but does not alter the wiring. After surgery, the orignial
corresponding retinal points no longer receive images from the same
object in space but the brain continues to operate as if they did.
This can lead to diplopia, suppression of one eye and does result in
the strabismus measuring differently when done subjectively (fusion
angle ) vs objectively (appearance of where eyes are pointing).

" I'm able to swithch fixating eye or look with both... does not it
mean that I'm "binocular" to some
extent ? "

No. Binocular means you use both eyes at the same time with a fused
image, not each eye at a different time.

Judy