Yes. Or rather, most likely. Glasses are a simple solution to a complex problem. They change the focal plane inside your eye in a static fashion – meaning, unlike your eye which can refocus at […]
Yes. Or rather, most likely.
Glasses are a simple solution to a complex problem. They change the focal plane inside your eye in a static fashion – meaning, unlike your eye which can refocus at many distances, glasses simply make a “one size fits all” adjustment to your focus.
This isn’t so much a problem if you have axial elongation based myopia. If you have pseudo myopia this treatment will likely cause progressive myopia (increasing myopia, worse vision).
The biggest problem with glasses meant for distance vision is when they are worn while focused up-close. This activity when prolonged significantly contributes to progressive myopia, and should be avoided. If you are already myopic and can’t see well enough up-close, a differential (reduced prescription) should be used for close-up work.
Glasses cause lens-induced myopia. A large body of research substantiates this fact. From the American Academy of Optometry:
Axial Myopia Induced By Hyperopic Defocus
“This study investigated whether adolescent guinea pigs can develop myopia induced by negative lenses, and whether they can recover from the induced myopia. Forty-nine pigmented guinea pigs (age of 3 weeks) were randomly assigned to 4 groups: 2-week defocus (n = 16), 4-week defocus (n = 9), 2-week control (n = 15) and 4-week control (n = 9). A −4.00 D lens was worn in the defocus groups and a plano lens worn in the control groups monocularly. Refractions in the defocused eyes developed towards myopia rapidly within 2 days of lens wear, followed by a slower development. The defocused eyes were at least 3.00 D more myopic with a greater increase in vitreous length by 0.08 mm compared to the fellow eyes at 14 days (p < 0.05). The estimated choroidal thickness of the defocused eyes decreased rapidly within 2 days of lens wear, followed by a slower decrease over the next 4 days. Relative myopia induced by 4 weeks of negative-lens treatment declined rapidly following lens removal.”
More reading here.
Also worthwhile reading, from ScienceDirect:
“Spectacle Lens Compensation. The homeostatic control of eye growth functions to keep images sharply focused on the retina. Therefore, if the eye length increases more slowly than does the focal length, the focal plane will be behind the retina, creating hyperopic defocus on the retina. The same occurs if one puts a negative lens over the eye (Figure 2A). To regain sharp focus, the retina needs to be displaced backward to where the image is. This is done in two ways: the eye is lengthened by increasing the rate of growth or of remodeling of the sclera at the posterior pole of the eye Gentle and McBrien 1999 and Nickla et al. 1997, and the retina is pulled back within the eye by the thinning of the choroid, the vascular layer between the retina and sclera ( Figure 2B; Wallman et al. 1995 and Wildsoet and Wallman 1995); once distant images are again focused on the retina (emmetropia), both the rate of ocular elongation and the choroid thickness return to normal.”
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