Vision defect

Vision Defect

A vision defect, also known as a refractive error, is a common eye disorder that impairs the eye's ability to focus light correctly on the retina. This results in blurred or distorted vision. The primary types of vision defects include myopia, hyperopia, astigmatism, and presbyopia.

Types of Vision Defects

Myopia

Myopia, or nearsightedness, is a vision defect where objects nearby are seen clearly, but objects farther away appear blurred. This occurs when the eye grows too long from front to back, causing light to focus in front of the retina instead of directly on it.

Hyperopia

Hyperopia, or farsightedness, is the opposite of myopia. People with hyperopia can see distant objects clearly, but close objects appear blurred. This happens when the eye is too short from front to back, causing light to focus behind the retina.

Astigmatism

Astigmatism is a vision defect that causes blurred vision at any distance. It occurs when the cornea or lens has an irregular shape, causing light to focus on multiple points in the eye instead of a single point on the retina.

Presbyopia

Presbyopia is an age-related vision defect that affects the ability to see close objects or small print. It is caused by the loss of elasticity in the lens of the eye, which makes it difficult for the eye to focus light directly on the retina.

Causes and Risk Factors

Vision defects are often hereditary and can also be influenced by factors such as age, eye strain, and certain medical conditions like diabetes.

Diagnosis and Treatment

Vision defects are typically diagnosed through a comprehensive eye examination. Treatment options include corrective eyewear such as glasses or contact lenses, refractive surgery, or in some cases, eye exercises.

See Also

• Eye health
• Optometry
• Ophthalmology