EDIT: Rectus muscle attachment to anterior chamber angle distance is positively correlated with axial length

EDIT: Sorry for such a big misunderstanding :frowning: . It’s “iris to muscle” instead of “annulus of Zinn to other end of muscle”. But I seen people teach even to perform exerises for scoliosis on the opposite side and people listening to them went worse.

As you see, the longer eye gets, the more distance from three of four straight muscles attachment to the side of pupil increases on average.

The exception is side muscle with attachment from the side of temple, also called lateral rectus. There was found even the opposite.

Even 0.1-0.2 mm of axial length difference between eyes affects this distance measurably as you will see in the Table 4. Axial length difference is found also in many emmetropes, this is the second thing I get from this study, as well as @Varakari wondering why the shorter eye is more myopic. Or @200citizenships with different AL yet equal eyes which gave us pretty useless (sorry :stuck_out_tongue:) AL measurements from differently calibrated different machines measuring it differently.

The study: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0243382

2 Likes

Nice find - I think we have under-estimated the role of the EOMs in the creation and the maintenance of myopia, and especially in the case of strabismus-induced myopia.

These exist, but eventually this forum might be not a perfect place to dig into details…
EndMyopia seem to do its job on lens-induced myopia with a relatively high success rate.
So any problems beyond could get left in the Science category forever.
As there are minorities having such.

Probably, but I only discovered since EM that I have probably had some mild strabismus all my life, leading to double the myopia in the left eye than the right. I have @kem to thank for alerting me to this. It is vertical rather than horizontal strabismus, which is probably less noticeable, and was certainly never picked up by any opto.

For those didn’t know, muscle contraction does not depend on shortening:

Muscle can contract independently of it being shortened (concentric) or lengthened (eccentric). Or being the same length (isometric). As seen from spinal muscles, muscles stuck in eccentric contraction undergo more bad changes and develop stiffness as compared to muscles stuck in concentric. Which matches my experience my rectus muscles being stiff - eye movement inwards when rectus muscles are engaged more when obliques is accompanied by stiffness.

Eccentric contraction develops when muscle is loaded with more force it can overcome. Ciliary muscle could “train” obliques if they contract with ciliary contraction. So, obliques could just shorten forever and rectus are constantly fighting them to hold the eye in place. So eventually rectus muscles suffer most.

I just laught at @halmadavid’s nonsense on astigmatism and gravely mistaken myself.

My hypothesis is even more radical - over 80-90% of myopes having stable progression of myopia have some degree of compensated converging strabismus (also called esophoria), at least in some gaze - lateral, upward, downward or straight.

You may be right, but few have the degree of strabismus that you seem to have. I don’t think the EM method is the most useful for dealing with serious EOM problems. It is a pity that your strabismus was not dealt with at an earlier age. My suggestion is that you find the best vision therapist available to you, and to work with them before considering EOM surgery. DIY vision therapy may actually be counterproductive without expert guidance. Deal with your EOM problems first before trying to figure out how to reduce your myopia. With some luck, they will improve together.

You are frustrated because you are not finding your ‘tribe’ on the EM forum. Perhaps you should look elsewhere for a group of people who have problems similar to yours. You may find more useful information and suggestions there. I know you are doing a lot of research on vision problems, but a little knowledge can be a dangerous thing without actual expertise and experience.

It was invisible, as it’s phoria. I suspect it was just appeared at 11, when my myopia reached -6. In recent years, it progressed. Just internal recti go in spasm after more long convergence.

Perhaps it’s some kind of divergence insufficiency (I have very little divergence range) due to high myopia.

Results from eye protruded up and to the side: external rectus slips down and upper rectus slips in, to the bridge side. Interesting enough, this could mean the most elongated part of eye is where obliques attach. That’s why I would consider surgery here, because I guess it’s uncorrectable before high myopia.

But it has some conflicting points, like monocular motility: while it looks weird in me (eye moves also slightly up when moves out, and moves slightly down when in), however it’s not restricted in any way.

You definitely need to see an expert on this.