Presbyopia: Age-Related Vision Loss
Age related vision deterioration
Presbyopia is the progressive loss of vision experienced by everyone as they age. It is different from other vision disorders, such as nearsightedness and farsightedness, which are caused by an irregularly shaped eyeball. Even people with perfectly shaped eyeballs who have had 20/20 vision their entire lives will experience some form of presbyopia if they live past the age of fifty.
Signs and Symptoms of Presbyopia
People begin noticing symptoms of presbyopia at some point in their 40s. They begin holding the newspaper and other reading materials at arm’s length, and get headaches when doing close work, such as writing letters or sewing fabric. They may also have a general feeling of eye fatigue when performing such tasks.
Presbyopia Causes
There are a number of theories as to what causes presbyopia, but most eye doctors subscribe to the explanation of a gradual loss of flexibility in the eye’s crystalline lens. Other popular theories include continued lens growth, and gradual atrophy of the muscles that control lens dilation.
Treatments for Presbyopia
The most common treatment for presbyopia is prescription eyewear, usually bifocals, progressive lenses, or reading glasses. Bifocals have two distinct prescription strengths – one on the top half of the lens and another on the bottom – while progressive lenses move gradually from one prescription to the other. Reading glasses are only worn when doing close work, such as reading or writing letters. There are also special contact lenses designed for presbyopes, called multifocal lenses. Yet another contact lens solution involves the use of monovision contacts, which are discussed below.
Other Presbyopia Treatments
Conductive Keratoplasty (CK) is used to correct presbyopia and create monovision in people age 45 and older. One eye is adjusted for near vision and the other eye for distance vision. During the CK procedure, the surgeon uses the light beams to increase the curvature of the cornea, improving vision almost immediately. It is suggested that presbyopic patients try monovision contacts before scheduling a CK procedure, as some patients experience dizziness with monovision. The human mind learns to favor one eye over another, depending on whether we are performing a near or far task. This takes time, however, so you should consult with your eye doctor before discontinuing your use of monovision contacts.
Possible Presbyopia Treatments on the Horizon
The following IOL Procedures have not been approved by the FDA for treatment of presbyopia. They are generally used as an alternative treatment Cataracts. However, they have promise as presbyopia treatments in the near future. Consult with a qualified LASIK Surgeon if you would like to know more about the following vision disorder treatments.
Click to View the Interactive Cataracts Vision Test
Crystalens is an intraocular lens (IOL) replacement procedure, in which the patient's natural lens is removed and replaced with a clear plastic lens. Crystalens surgery has the added benefit of preventing cataracts (another common age-related vision disorder) in the future.
ReStor® and ReZoom® are IOL replacement procedures that utilize patented technologies to provide a greater range of vision than other IOL procedures. The lens is convex on both sides. It is folded and inserted into the patient's eye through a microscopic incision. Once inserted, the lens gently unfolds itself and restores both near and distant vision. The most common use for either procedure is in lens replacement after cataract surgery. However, many refractive surgeons are implanting them as replacements to the natural lens for the purpose of restoring both near and far sight. As with Crystalens surgery, both ReStor® and ReZoom® have the added benefit of preventing cataracts in the future.
Diagnosing Presbyopia
If you are over the age of forty, all eye exams performed by your optometrist or ophthalmologist should include testing for presbyopia. The condition worsens as we age, so presbyopia treatments may have to be repeated every three to five years.
