Hypermetropia

What is Hypermetropia?

Hypermetropia is also referred to as hyperopia or long-sightedness, or far-sightedness. Hypermetropia is the condition of the eyes where the image of a nearby object is formed behind the retina. Here, the light is focused behind the retina instead of focusing on the retina.

The picture below helps you to understand the cause of hypermetropia in a better way.

The person suffering from hypermetropia will have difficulty focusing on nearby objects but can clearly see distant objects. Accommodation is the process used to treat hypermetropia without any defects in vision in the early stages.

Hypermetropia is mainly caused due to certain structural defects in the retina. Structural defects include:

• Small-sized eye-ball
• Non-circular lenses
• The cornea is flatter than usual
• Defective blood vessels in the retina
• Weakness in ciliary muscle
• Changes in the refractive index of the lens
• Alterations in the position of the lens or absence of lens
• Low converging power of eye lens

Risk factors include:

• Cancer around the eye
• Some medications
• Diabetes
• Small eye syndrome (microphthalmia)

Symptoms

This problem shows no major symptoms initially but later leads to a mild aversion to light, blurry vision, watering, tiredness in eyes, inward turning of the eyes and causes headaches too.

Types of Hypermetropia

Clinically far-sightedness is classified based on the structural appearance of the eyes, severity, or how the eyes respond to the accommodative status:

Based on the structure of the eye, hyperopia is classified into:

• Simple hyperopia: It is caused due to biological diversity.
• Pathological hyperopia: It is caused by abnormal development of the eye, disease, or trauma.
• Functional hyperopia: It is caused by paralysis that interferes with the eye’s ability to accommodate.

Based on severity hypermetropia is classified into:

• Low Hypermetropia: Refractive error is less than or equal to +2.00 diopters (D).
• Moderate Hypermetropia: Refractive error is more than +2.00 D up to +5.00 D.
• High Hypermetropia: Refractive error is beyond +5.00 D.

Based on the accommodative status hypermetropia is classified into:

• Total hypermetropia
• Latent hyperopia
• Manifest hyperopia

Comparison of image focus by a normal eye and eye with hypermetropia condition is as shown in the figure below.

Treatment

• Usage of proper corrective lenses and spectacles as prescribed by the ophthalmologist can help to overcome Low Hypermetropia.
• High degree hypermetropia is corrected using intraocular lens implantation.
• Surgery like LASIK (Laser-Assisted In situ Keratomileusis) Laser eye surgery, PRK (Photo-Refractive Keratectomy) and LASEK (Laser Subepithelial Keratomileusis).

Related links

Related links
Human Eye	Unit of force
Uniform Circular Motion	Myopia

Watch the video below to learn how and why spectacles/contact lenses are used to correct defects of vision and how exactly they affect the human eye

Frequently Asked Questions – FAQs

Q1

1. What is Hypermetropia?

It is the condition of the eyes where the image of a nearby object is formed behind the retina.

Q2

2. What is accommodation?

Accommodation is the process used to treat hypermetropia without any defects in vision in the early stages.

Q3

3. Based on the structure of the eye, how is hypermetropia classified?

Simple hyperopia, Pathological hyperopia, Functional hyperopia

Q4

4. What are the symptoms of hypermetropia?

Blurry vision, watering, tiredness in eyes, inward turning of the eyes and headaches.

Q5

5. Based on accommodative status, how is hypermetropia classified?

Total hypermetropia, Latent hyperopia and Manifest hyperopia

Watch the video and solve the previous year questions in the chapter The Human Eye and Colorful World Class 10

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