Difference between revisions of Axial length
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[[Hyperopic defocus]], excessive [[myopic defocus]], form deprivation, and [[accommodation]] strain can all cause [[axial elongation]]. In particular, using distances glasses for close-up is a very common cause of it. | [[Hyperopic defocus]], excessive [[myopic defocus]], form deprivation, and [[accommodation]] strain can all cause [[axial elongation]]. In particular, using distances glasses for close-up is a very common cause of it. | ||
==Further Reading== | |||
* https://pubmed.ncbi.nlm.nih.gov/19204786/ | |||
* https://chemport.cas.org/cgi-bin/sdcgi?APP=ftslink&action=reflink&origin=karger2&version=1.0&coi=1%3ACAS%3A528%3ADC%252BD1MXitFOgsLo%253D&md5=9cabd3078e641623141a8226331cdead | |||
* https://endmyopia.org/wp-content/uploads/2017/02/Reduction_in_Axial_Length_with_Age__An.3.pdf | |||
* https://iovs.arvojournals.org/article.aspx?articleid=2126435 | |||
==References== | ==References== | ||
Revision as of 08:21, 2 February 2022
Axial length of the eyeball is the distance from the lens to the retina. Axial elongation is the scientifically accurate reason why most myopes have myopia, as other causes are rare.
Biology
It would require precision engineering to be able to grow an eye that was perfectly emmetropic at birth. Instead, it is of approximate dimensions, and feedback during postnatal development tunes the axial length to match the focusing system. Two mechanisms are available: changing the thickness of the choroid, and changing the length of the eyeball itself. [1]
How it can be reduced
Myopic defocus, as well as conscious accommodation of the ciliary muscle during active focus, can cause axial shortening. Having good close-up and distance vision practices helps.
How it can be increased
- Main article: Axial elongation
Hyperopic defocus, excessive myopic defocus, form deprivation, and accommodation strain can all cause axial elongation. In particular, using distances glasses for close-up is a very common cause of it.
Further Reading
- https://pubmed.ncbi.nlm.nih.gov/19204786/
- https://chemport.cas.org/cgi-bin/sdcgi?APP=ftslink&action=reflink&origin=karger2&version=1.0&coi=1%3ACAS%3A528%3ADC%252BD1MXitFOgsLo%253D&md5=9cabd3078e641623141a8226331cdead
References
- ↑ Wallman J, Winawer J (2004). "Homeostasis of eye growth and the question of myopia". Neuron. 43 (4): 447–68. doi:10.1016/j.neuron.2004.08.008. PMID 15312645.Page Module:Citation/CS1/styles.css has no content.