Why do we need reading glasses? Can I avoid reading glasses? What can I do instead of using reading glasses? This article aims to help answer some of these questions and help normalize the need for “cheaters”!
Natural Aging of the Eye
When it comes to creating vision, light must be given off by an object and come to land perfectly on the back most structure of the eye, the retina.
The retina contains specialized cells called photoreceptors which detect light and then transmit signals to the brain for image processing and formation.
In order for light to reach the retina appropriately, it must be bent and refracted so that it lands directly on the retina. If light comes to a focus in front of or behind the retina, it creates blur.
Therefore, a glasses prescription is needed anytime the eye is unable to correctly refract light on its own. Refraction of light is based upon two major factors—the cornea and the lens.
The cornea is the front most structure of the eye. It is clear and covers the colored part of your eye (iris).
The cornea is the first layer of the eye that refracts light. If its shape is slightly off—too steep or flat in curvature—it will refract light incorrectly.
The cornea is what is corrected in refractive surgery—LASIK, SMILE, PRK, etc.—as it can be reshaped with lasers.
The lens, on the other hand, is a bit more complex.
When we are young our lens flexes naturally in a process called accommodation to allow us to see both up close and far away.
As we age, the lens becomes less and less flexible in a process called presbyopia.
Presbyopia typically sets in around the age of 45—earlier in some individuals and later in others.
While you may be able to work through it temporarily, the accommodative capabilities of the lens will continue to lessen and lessen until reaching about 0, or absolute presbyopia. This typically occurs by the late 50s to early 60s.
There is currently no perfect fix for presbyopia, although research is ever-changing the field.
Cataracts vs. Presbyopia
Presbyopia is defined as a loss of accommodation, resulting in the ability to see only at one fixed distance. The set distance that is clear is variable depending on the person’s corneal refractive error.
Individuals who are low myopes (near-sighted) may retain the ability to see up close, but will require glasses to see at distance.
Individuals who are low hyperopes (far-sighted) may retain the ability to see far away, but will require glasses to see up close. These individuals may notice an earlier onset of presbyopia as well, as some accommodation is needed at all distances to “correct” their hyperopia.
Individuals who have no refractive error (had previous LASIK, PRK, or other refractive surgery or simply were born this way) will be able to see well at distance, but will require glasses for near work.
Presbyopia is a loss in the flexibility of the lens so that it can no longer clear images at a variety of distances. Cataracts, on the other hand, are changes within the lens in which the typically translucent lens becomes opaque and can interfere with vision.
With cataracts, the lens turns a yellowish color (responsible for a slow dimming affect of colors over time), hardens, thickens, and becomes dense and opaque.
These changes result in light scatter creating blur, glare, halos, and light sensitivity, decreased vision due to less light reaching the retina, decreased contrast and a dimming of colors, and several other inconveniences.
Cataract formation is usually slow. Due to this, symptoms of cataracts often go unnoticed until the cataract has progressed to a moderate/severe stage, or until after the cataract is removed and replaced with a clear artificial one.
First signs of cataract development begin around the age of 40 and progress until the cataract is removed via surgery—typically when an individual is in their late 60s to early 70s, although there is set age for surgery, some individuals are more sensitive to lens changes than others.
While presbyopia is a separate issue from cataract formation, cataract surgery can be used to help presbyopia slightly.
The artificial lens that replaced the natural lens in surgery is personalized to an individuals’ prescription and needs. Most individuals choose to have clear distance vision and wear reading glasses for near work. Others may choose to have clear near vision and a pair of distance glasses.
There are also multifocal lens implants. Multifocal lens implants allow for an extended range in vision—typically good distance vision with some intermediate abilities (computer range). An individual will still need reading glasses for extended periods of reading work, however he or she will be able to “get by” much better without reading glasses with a multifocal artificial lens.
Another option with cataract surgery is to do a monovision setup. Each lens is set for a given distance—one eye for distance and the other for near. With both eyes open, the individual will be able to see both up close and far away.
Monovision works for many, but sometimes the inequality between the two eyes can cause issues like increased glare, headaches, or may just be intolerable to some. It is recommended to try monovision contact lenses prior to getting monovision cataract surgery done to mimic its effects.
Managing Presbyopia
For most, signs of presbyopia come decades prior to the need for cataract surgery. So what can be done to help those individuals?
Currently, the two options are contact lenses and reading glasses.
Multifocal contact lenses or monovision can be prescribed by your local eye doctor to help correct your distance prescription and give you some reading capabilities up close. Like multifocal cataract surgery, these contact lenses are not perfect—there is some give and take—however they do drastically increase your range of vision.
Reading glasses are by far the most popular option.
For those with satisfactory distance vision, over the counter “cheaters” can be purchased at local drug stores, grocery stores, online retailers, and more.
The point to know with over the counter reading glasses is that they are set to work at one distance. Those earlier in the presbyopia course, who still have a little accommodation left, may be able to get by using one pair for intermediate distances and near.However, as the presbyopia progresses this will be unattainable.
The trick with over-the-counter reading glasses is that the higher the power, the closer the working distance. For example, a +2.50 equates to a working distance (where the material should be held for the clearest vision) of 40 centimeters. +1.50, on the other hand, is more commonly recommended for computer work with a working distance of 66 centimeters.
It can be helpful to get multiple pairs of varying powers from the dollar store and mess around with them until finding the perfect pair to suit your needs.
Another option with reading glasses is to get a prescription pair from an optometrist. This is especially helpful if you have a baseline prescription—myopia, hyperopia, and/or astigmatism—as the reading glasses are made personalized to your needs.
Prescription glasses also offer other options such as bifocals (a distance prescription on top with a near at the bottom), trifocals (distance, intermediate, and near), or progressive lenses (no lined bifocals with a progressively increasing power from distance to near).
Specialized glasses for computer work and near can also be made for those who spend a lot of time doing office work.
Whatever you choose, presbyopia is not a condition that needs to be suffered in silence! Everyone will experience it, this is unfortunately one of those unavoidable birthday gifts. If over-the-counter readers are not cutting it for you, call your local optometrist and they will be happy to talk over different options with you to get you seeing great at distance and near again.
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