Finding out you need to wear glasses may come as a relief if you can suddenly see clearly but it may also come as a surprise if you saw clearly before. There are multiple reasons for needing glasses and not all glasses are only for correcting blurry vision.
What is Healthy Vision?
Vision is an active process that is much different than just simply seeing. If someone can physically detect an object, they can see it but to interpret, analyze, and form a coherent thought about the object requires vision.
With this definition, it is possible to begin to understand why not all visual issues are solely related to blurry vision.
Certainly, if an object is not clear and appears blurry that is not healthy vision. This is the case for nearsighted individuals who need glasses to see clearly.
However, if words run together move around on the page when reading that is also not a healthy visual system despite the fact that the words may be clear.
For an individual to have healthy vision, it must be clear, single, and flexible. If an object appears blurred, an object appears double, or if the visual system cannot interact with the object appropriately, then the vision is not healthy.
Glasses for Blurry Vision
The most common reason for needing glasses is to correct blurry vision. Whether the blurry vision is in the distance (such as nearsightedness), up close (such as farsightedness), or both (such as astigmatism), glasses can be useful to provide clarity in these cases.
These glasses will make a noticeable difference once they are worn for the first time.
In many cases, if you need glasses for blurry vision, you will always need glasses, contact lenses, or have to have a refractive surgery.
To determine if glasses can improve your blurry vision, your eye doctor will perform a refraction by trying different lenses to find the best option for your glasses.
Glasses for Double Vision
A much less common use of glasses is for double vision. If an individual is seeing double of an object, at distance or near, it is a concern.
In these cases, concerning diseases such as a stroke or tumor must be ruled out, but if they are, it may require glasses to help relieve the double vision.
In these glasses, your eye doctor may use prism or may occlude part of one of the lenses.
To determine if you need to wear glasses to help with double vision, your eye doctor will perform a variety of tests including trying different prism powers and partial occlusion of the eye.
Inflexible Vision
In a healthy individual, vision is flexible in that it can move from object to object and different distances without any issue.
If there are issues with eye coordination or focusing, then glasses may be prescribed to assist the eyes in becoming appropriately flexible.
The testing required is highly variable based on the reason for needing the glasses and the best course of testing will be determined by your doctor.
The Importance of Wearing Glasses
If you have prescription glasses, it is very important to follow the directed wearing instructions. Most glasses are designed to be worn full time, both distance and near but there are instances in which a pair of glasses may be prescribed for only distance or only near.
Any issue corrected by wearing glasses can continue to progress or cause other issues if the glasses are not worn appropriately and consistently.