What Is Considered Extreme Farsightedness?
An eye doctor will diagnose extreme farsightedness when you can’t focus on an object unless it’s about a yard or two away. When your eye’s natural lens loses its flexibility, it causes presbyopia.
You would need corrective glasses to see and interact with objects nearby, such as reading the newspaper.
About Presbyopia or Farsightedness
Presbyopia refers to the gradual loss of the ability of the lens in your eyes to focus actively on nearby objects. You would need about a foot of clearance for your eyes to see something. The word Presbyopia is Greek for ‘old eye’; apt, considering the main cause of the condition is old age.
You will inevitably have presbyopia as you get older, with eyesight typically starting to deteriorate at age 40.
For ages 45 to 55, 80 percent of the adult population will have this age-related condition. The lens hardens and loses the ability to change shape with age, which means you can’t focus on nearby objects.
Doctors use various instruments to get a presbyopia diagnosis, and a routine eye exams can determine if you have farsightedness or nearsightedness. The test involves an eye health exam and refraction assessment using various lenses.
Levels of Farsightedness
The standard unit of measure for optical power is diopters (D), which is normally used to measure farsightedness. The American Optometric Association gives the following levels of farsightedness:
- Mild: refers to any measurements below +2.00D
- Moderate: if the eye doctor gives you a score between +2.25 and +5.00, it shows you have moderate farsightedness
- Severe/extreme farsightedness: this is anything measured at +5.25 and beyond
The sphere (SPH) or spherical error represents your level of near or farsightedness. If your score is – (negative) it means you’re nearsighted, while a + (positive) number denotes farsightedness.
0 (zero) represents perfect sight, and vision gets worse the more it shifts away from zero in either direction. The further away you can see a close object determines the level of your farsightedness.
The lens in your eye stiffens with age, losing flexibility and ability to focus on nearby images. Eye lens hardening means light from nearby things can’t focus directly onto your retina.
Diagnosing Farsightedness and Presbyopia
You can tell if you are struggling with farsightedness or presbyopia if your vision is blurry, and you have trouble focusing clearly on things that are close. There are additional signs of farsightedness.
- Eye strain
- Trouble seeing clearly in dimly lit locations
- Needing to hold things away from your eyes to see better
- Difficulties reading books, newspapers, menus, or anything else up close
You will probably be able to self-diagnose presbyopia or farsightedness just by recognizing that things appear blurry up close. To determine the level of farsightedness that you suffer from and to get an official diagnosis, you will need a comprehensive exam from an ophthalmologist. Farsightedness can often be missed by an eye exam that includes reading letters off of a chart, as that only checks for myopia, or nearsightedness.
To check for farsightedness, your eyes will typically need to be dilated. The American Academy of Ophthalmology (AAO) explains that a special light will be shined in them, and a retinoscope is then used to measure how the light is reflected off the retina. Other specialized instruments, such as a phoropter, can be used to measure the level of the refractive error.
Treatments for Farsightedness
There are four main ways to treat presbyopia:
- Reading glasses
- Bifocals, trifocals and progressive lenses
- Contact lenses
- Refractive surgery
These help bend (refract) light before entering your eyes, thereby correcting farsighted issues. How powerful the reading glasses need to be depends on your level of farsightedness.
Bifocal, Trifocal and Progressive Lenses
If you’re already wearing glasses, you might need to supplement those with:
- Bifocals: They correct far and close-up vision. There’s a line on your glasses that separate the different types of lenses. The upper part corrects distant vision distortion while the lower bottom refracts light so you can focus on nearby objects.
- Trifocals: Similar to bifocals, these glasses have three lens areas that help correct far, near and mid-range vision
- Progressive lenses: These can operate like bifocals or trifocals except that the lenses show no clear line dividing the lens areas as refraction shifts gradually between the different vision zones.
These work like lenses, but they sit directly on the surface of our eyeballs. They refract light, bending it to ensure clear vision. Examples include soft, monovision, and gas-permeable contact lenses.
Surgeries aim to correct blurry vision. The type of surgery the ophthalmologist recommends depends on the severity and type of your farsightedness. There are three main types of refractive surgeries for treating farsightedness:
- LASIK: Most people prefer this procedure for correcting hyperopia. It involves creating a flap, gently pushed aside, and some underlying tissue removed before placing the flap back. LASIK works a treat in mild to moderate farsightedness, with limited success over severe farsightedness.
- PRK (Photorefractive keratectomy): Unlike LASIK, the surgeon will remove the thin flap created on the cornea completely before reshaping the material underneath. PRK is very similar to LASIK, so it’s not appropriate for people with high farsightedness.
- Refractive Lens Exchange (RLE): This is one of the best solutions for treating severe farsightedness. The procedure involves the eye surgeon replacing your natural lens with a new one, often a synthetic intraocular lens (IOL). It’s the same procedure as cataract surgery, without the cataract. RLE is a capable procedure for remedying farsightedness, often recommended to people who don’t qualify for LASIK or PRK.
- Phakic IOL (pIOLs): This procedure mainly treats hyperopia. The surgeon will place an IOL either in front or behind the iris without removing the lens.
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