Usually experienced by people aged 40 and above, presbyopia is a condition where the eye loses its natural ability to focus on near objects. You suddenly find it hard to do things such as reading, sewing or working at the computer. Presbyopia is an inevitable part of aging.
The most noticeable symptom of presbyopia is difficulty reading unless you hold the material at arm’s length. When they perform near work, such as embroidery or handwriting, they may develop headaches, eye strain or feel fatigued.
Presbyopia is an age-related process. This differs from astigmatism, nearsightedness and farsightedness, which are related to the shape of the eyeball and caused by genetic and environmental factors. Presbyopia generally is believed to stem from a gradual thickening and loss of flexibility of the natural lens inside your eye as we age.
These age-related changes occur within the proteins in the lens, making the lens harder and less elastic over time. Age-related changes also take place in the muscle fibers surrounding the lens. With less elasticity, the eye has a harder time focusing up close.
Presbyopia Treatment: Eyewear
Eyeglasses with bifocal or progressive addition lenses (PALs) are the most common correction for presbyopia. Bifocal means two points of focus: the main part of the spectacle lens contains a prescription for distance vision, while the lower portion of the lens holds the stronger near prescription for close work.
Progressive addition lenses are similar to bifocal lenses, but they offer a more gradual visual transition between the two prescriptions, with no visible lines between them.
Reading glasses are another choice. Unlike bifocals and PALs, which most people wear all day, reading glasses typically are worn just during close work.
If you wear contact lenses, your eye doctor can prescribe reading glasses that you wear while your contacts are in. You may purchase readers over-the-counter at a retail store, or you can get higher-quality versions prescribed by your eye doctor.
Presbyopia Treatment: Surgery
Surgical options to treat presbyopia also are available. Radio waves are sometimes used to create more curvature in the cornea for a higher “plus” prescription to improve near vision. This is performed on one eye only for a monovision correction but the correction is temporary and diminishes over time.
PresbyLASIK is a new presbyopia-correcting surgery. This innovative procedure uses an excimer laser to create a multifocal ablation directly on the eye’s clear surface or cornea. This enables vision at multiple distances.
LASIK also can be used to create monovision, in which one eye is corrected for near vision while the other eye is stronger for distance vision.
A highly experimental treatment being studied is the injection of an elastic gel into the capsular bag, the structure in the eye that contains the natural lens. In theory, the gel would replace the natural lens and serve as a new, more elastic lens.
Experiments also have centered on laser treatment of the eye’s hardened lens to increase its flexibility and thereby improve focus.
With the recent introduction of presbyopia-correcting intraocular lenses, some people undergoing cataract surgery may be able to achieve clear vision at all distances.
Also, an elective procedure known as refractive lens exchange may enable you to replace your eye’s clear but inflexible natural lens with an artificial presbyopia-correcting lens for multifocal vision.