Trabecular Meshwork as functional antagonists of the Ciliary Muscle

I’ve found something interesting :slight_smile: The article is more about glaucoma so unless you are interested in that, I don’t recommend to read it (especially not fully), but it have an interesting postulate on which it bases it’s theory.

I always had a bit of problem with the “ciliary spasm” theory, because as @bachus argued in the other topic ( ) usually you need a counter-force to relax a spasm. If the spasm in your legs, you can use stretching for that, or simply using the antagonist muscle, because most muscle have those. But for obvious reasons you cannot stretch externally your ciliary muscle, nor it have antagonist muscle in the classical model. It only have the zonular fibers which is a passive ligament.
So some data points:

  1. If there is ciliary spasm and you can release it somehow, then something have to pull against it.
  2. Based on experiences most likely the improvement in Endmyopia is thanks to the AF practice.
  3. I think (almost) everyone’s experience is that you cannot hold AF for long. And when you start Endmyopia you can hold only for a really short time and it gets longer with time

So if we accept the 1) and add the 2) then we have to conclude that AF is somehow releases the ciliary muscle. The 3) suggest that it’s some muscle action: if you can relax a muscle (ciliary in this case) why would you not be able to let it be relaxed for a longer time? At least until you look elsewhere or look close-up, which needs the activation of the muscle. But if you don’t relax the ciliary muscle for AF, but use another muscle contraction for stretch the ciliary muscle then 3) is explained: for obvious reasons you cannot contract a muscle for too long. Especially not if you not used that muscle (correctly) for a long time.

So to come back to the article I linked above: they say that the Trabecular Meshwork is not a passive element, like in the classic model, but:

ample evidence supports the theory that trabecular meshwork possesses smooth muscle-like properties … In this model, trabecular meshwork and ciliary muscle appear as functional antagonists

For reference studies check the full paper on sci-hub, they reference 6 studies on this matter. No way I will check them, this one was more than enough :smiley: I mean it have figures like this:
I don’t even… :smiley:

Anyhow, back to our topic. If they (and the other guys in the reference studies) are correct then we have an antagonist muscle for the ciliary muscle: the Trabecular Meshwork.

If you are interested more about it, use google :slight_smile: The point is that it’s in the eye, connected with the ciliary muscle and can acts as an antagonist. Which can answer the “How can you release a spams in the eye?” and “Exactly what muscle works during AF?” questions.
Also it answers another one: “Why AF is so mystical and hard to find?”: because the Trabecular Meshwork works like a smooth muscle. You have no conscious control on those muscles. So just like you cannot make your heart beat faster (or slower) consciously and directly, you cannot make the Trabecular Meshwork contract consciously (I know that heart is not a simple smooth muscle, but in this regard it works like that and more understandable example than if I cite the Arrector pili muscle). But as you can influence your heart beat, you can influence this “muscle” too. And it would explain why finding AF needs such indefinable and “guruesque” things like “make sure you relax”, “just want things to get into focus”, “find a nice sunny day when you have no other thing to do”, “just look at the words”, etc. Because it’s even worse than learning wiggle your ears: you have direct control on your head muscles. But you don’t have on this.

As a footnote, because it have nothing to with Endmyopia:
For me it would make the Ortho C theory more simple and more logical: if instead of the special plano contact lens more or less miraculously relax the oblique muscles, the lens would add additional support or force to the Trabecular Meshwork (if you check where it is, it really close to where the lenses connect to the sclera), then it’s easy to see why putting in the lens would help to relax the ciliary muscle, even to the point of total relaxation (according to Ortho C if you have low myopia, so no axial elongation, just putting the special plano lens in makes you reach 20/20).


What a nice rabbit hole! I will take the time to investigate it.

Ooops, way above my paygrade - I will content myself with reading abstracts.
The ciliary muscle is also smooth muscle,aqueous%20humor%20into%20Schlemm’s%20canal.


Added some picture about the trabecular meshwork to the op.

Also realized it can explain my previous hypothesis better:

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The article seems to be saying that the Trabecular Meshwork is a functional antagonist with the ciliary muscle in regards to “regulation of aqueous humor outflow and intraocular pressure”. Wikipedia says it “is responsible for draining the aqueous humor from the eye via the anterior chamber”.
I don’t see any mention of it being able to relax the ciliary muscle to flatten the lens, though that is an interesting theory to consider.

They are researching on glaucoma, they don’t care about myopia at all. So they did not deal with any kind of implication of lens and focus. So I only took that there is a muscle which can act against the ciliary and build the hypothesis from there.

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About Ortho C, it views rectus muscles as antagonist muscles to ciliary body.
When rectus muscles are contracted, ciliary body should completely relax.

In my eyes, I can enforce ciliary muscles to relax or contract far away, no matter I use overcorrection or not. Not being able to relax ciliary muscles when viewing things at 7 cm from both eyes.

Yet another reason to practice squinting.

No, in their theory the rectus muscle is responsible to hold the sclera in the correct shape. Which it not able to do if the oblique muscle is in spasm. There is no connection in Ortho C between the ciliary and the rectus muscle.

I correctly remember in Yee’s book that contraction of the rectus muscles stimulates to relax ciliary muscles even more. Not a direct effect; but that is the way biomechanics fly.

Squinting causes irregular astigmatism.

Maybe constant squinting.

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As well as winking. Winked left eye now has it slightly irregular, but this usually disappears in short time.

Then check again. I don’t have time to skim through the public part of the book (and I don’t have the full), but in his science paper he clearly states:

The rectus muscles allow for the lengthening of the sclera by relaxing their tension.

Maybe you remember this:

The rectus muscles are on standby to allow the shape of the sclera to elongate if necessary to alleviate the tension of the ciliary muscle during prolonged near focusing

But this is not about letting the ciliary to relax while try to look into the distance, but about helping the ciliary not tension up that much during close-up.

No, I didn’t. I totally believed that there is only one rectus muscle and there is one oblique muscle :man_facepalming: Also you should have mentioned that I used sclera in single altough we have two eyes and so two sclera.

That does not falsify theory that they also help lens to flatten.

Yes, I can’t find that in Yee’s book, but that’s maybe takes place in Doonan’s model of accommodation. And I don’t have enough stamina to search more in Yee’s book.

Your theory is interesting and may be true, but it seem to be quite strange.

Well, all is way more complex than we think.

As I see in Yee’s book, lens can bulge regardless of ciliary muscle, because vertical length of eye may decrease when oblique muscles are tight so it will stretch zonule fibers and lens will bulge. If I understand correctly.

Also, there is no relationship between oblique muscles and ciliary muscle. Thus, oblique muscles maintain the tightness of ciliary muscle indirectly, by pressing on some eyeball structures that makes easier for ciliary muscle to stay in some tightness rather than in full relaxation.

That is too much off topic, but neither I nor you have correct understanding.

Well that is very interesting. I know science doesn’t turn on whether I like it or not, but I really like this idea. :laughing: I can imaging that what I feel happening could fit with an explanation like this.
If this trabecular meshwork were related to AF and also to aqueous humor outflow and intraocular pressure, would that also provide a potential line of inquiry for the frequent increased floaters reports?

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Yup. This whole premise has been floating about in BackTo20/20 for a while and is making it into more recent change logs.

Functionally there is an issue when users go to suddenly a much higher distance vision requirement - and rather than expected either no change in improvement rate, or increased improvement rate, they actually encounter more strain symptoms and in some cases even regression.

A longer story of course, this just as a bit of a side-and-foot note.

I’ve been mulling the trabecular meshwork function as a potential piece of that part of the ongoing puzzles of all the everythings.


So here’s a funny one. I was just researching the impact of NO (Nitric oxide) on relaxing the Ciliary, when I came across this post and in turn the below article.

If I’m reading it correctly. Ciliary and Trabecular Mesh-work can be relaxed/affected by NO. Which could in turn not only affect accommodation but also affect IOP.


I am resuscitating this post, as I suddenly remembered that humming increases the level of NO in the body. So we should hum for a while before testing our vision? I suppose this would only work if the ciliary muscles are in some spasm as I see no way of relaxing them beyond their natural limits of relaxation. Of course a change in IOP will also affect vision.

Wouldn’t it be a lark if humming improves distance vision. :crazy_face:
This also reminds us of the importance of nose, and not mouth, breathing.

Combine it with yoga breathing, if you will.

The drop in blood pressure is likely to be because of the increase in NO.


Here we also get into the unicorn farming IMO - refusing to go into the unicorn farming in the other aspects.

Those humming and yoga breathing with IOP affecting refraction… Eh sorry, but I thought I am the most crime of betraying EM with unicorn farming.


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