# Eye Shape in Emmetropia and Myopia

“Although there are considerable individual variations, in general myopic eyes are elongated relative to emmetropic eyes, more in length than in height and even less in width. Approximately a quarter of the myopic participants fitted each of the global expansion or axial elongation model exclusively. The small proportions are due primarily to the large variability in the dimensions of emmetropic eyes.”

If myopic eyes are shorter in width and longer in height, there is should be a diagonal which is equal in length. If that diagonal matches the angle of oblique muscles attachment, then it could be a next brick in building an evidence for / discovering the cause of myopia as abnormal strength/weakness of extrinsic eye muscles.

Even if results are not equal or opposite, we should think why such a deformation exist, because internal eye mechanics (intraocular pressure) should pump an eye symmetrically.

Why extrinsic muscles have limits, how much it can converge/diverge/rotate/turn the eye? Maybe also intraocular pressure is their limiter/antagonist, along with opposite muscle.

Perhaps there is an issue with language here? The way I see it, this is:

• Eyes are elongated on the length axis
• Less elongated in height
• Even less elongated in width

Meaning that the width of a myopic eye is the same or slightly longer than that of the eye of an Emmetrope. Not shorter. So it should be longer than the normal eye in every axis, even if the overall eye shape (ratio of length to width) is not the same.
Unless I am misunderstanding your point?

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Yeah, it’s quite my mistake. I skipped the results, because I didn’t guess there is unclear language:

“With an increase in myopic refractive correction, myopic eyes became much larger in all three dimensions, but more so in length (0.35 mm/D, 95% confidence interval [CI] 0.28–0.40) than in height (0.19 mm/D, 95% CI 0.09–0.29) and more so in height than in width (0.10 mm/D, 95% CI 0.01–0.20). Based on height and length dimensions, 25% and 29% of myopic eyes exclusively fitted global expansion and axial elongation models, respectively. Based on width and length dimensions, 17% and 39% of myopic eyes exclusively fitted the global expansion and axial elongation models, respectively.”