Light bends when it passes through different substances, such as air, water, or glass, resulting in refractions. In the context of vision, refractions play an important role in focusing light onto the retina, enabling us to see clearly objects. Here, we explore the causes, symptoms, diagnosis, treatment, and prevention of common vision problems related to refraction.
Causes
Refractions are caused by irregularities in the shape of the eye that affect the way light is focused onto the retina. Common causes include:
-
The eye is too long or the cornea is too steep, causing light to focus in front of the retina instead of directly on it.
-
Hyperopia (farsightedness): The cornea is too flat or the eye is shorter than normal, causing light to focus behind the retina instead of directly on it.
-
In astigmatism, the cornea or lens is irregularly shaped, resulting in blurred or distorted vision.
-
An age-related loss of flexibility in the lens that makes it difficult to focus on close objects.
Symptoms
Refractions can cause vision problems such as:
-
When viewing objects at certain distances, vision becomes blurry
-
An inability to see objects at a close distance (near vision) or from a distance (distant vision)
-
Reading or screen time can cause eye strain or fatigue
-
Especially around the eyes or forehead, headaches
-
To improve vision, squinting or tilting the head
-
Driving at night or in low light conditions is difficult
Diagnosis
A comprehensive eye examination by an optometrist or ophthalmologist is necessary to diagnose vision problems related to refractions. Diagnostic tests may include:
-
An eye chart is used to measure the clarity of vision at various distances.
-
The refraction test determines the correct prescription for corrective lenses by measuring how light is refracted by the eye.
-
Examining the retina and optic nerve at the back of the eye.
-
Glaucoma screening with tonometry.
Treatment
Refraction-related vision problems are usually treated with corrective lenses or refractive surgery.
-
The term eyeglasses refers to prescription eyeglasses with lenses that compensate for refractive errors, such as nearsightedness, farsightedness, astigmatism, or presbyopia.
-
A contact lens is a soft or rigid lens that corrects refractive errors and provides clear vision without the need for glasses.
-
LASIK or PRK are refractive surgeries that permanently correct refractive errors by reshaping the cornea.
Prevention
Refraction-related vision problems can be prevented by:
-
Monitor vision changes and detect refractive errors early with routine eye exams.
-
Wear safety glasses or goggles during activities that pose a risk of eye injury.
-
A healthy lifestyle promotes eye health and reduces vision problems by maintaining a balanced diet, staying hydrated, and avoiding smoking.
