Hypermetropia
Causes of Hyperopia
In a “perfect” eye known as Emmetropia, vision is clear for everything far and near. When light enters an Emmetropic eye it focuses directly onto the Retina (photo) (the area at the back of the eye responsible for light absorption) and this results in clear focussed vision.
In a Hyperopic eye however, light entering the eye focuses behind the retina (photo) thus resulting in more blurry vision for near objects. This may be caused by:
- The eyeball being too short thus the eye is unable to focus light on the retina – known as Axial Hypermetropia
- The Cornea (clear window at the front of the eye) or Crystalline Lens (the flexible structure in the middle of the eye) are too flat in shape or too weak thus inhibits the eyes ability to focus light on the retina – known as Refractive Hypermetropia
Severity of Hyperopia
- Low Hyperopia is considered around 0.00D to +2.00D
- Moderate Hyperopia around +2.00D to +5.00D
- High Hyperopia around >+5.00D
In higher levels of hyperopia, far vision may also become blurred.
- Clear vision for far/distant objects but blurry/unclear vision for close/near objects
- Eyestrain/headaches when doing near work tasks e.g reading/using computer
- Rubbing/squinting your eyes
In some cases, particularly in children as their eyes are still developing, there may be no obvious signs or symptoms of Hypermetropia.
Undiagnosed Hypermetropia in a young child can lead to problems such as development of Lazy Eye or a Squint.
Hypermetropia is often confused with an eye condition called Presbyopia which also causes blurred vision for near/close vision tasks and usually affects adults in their 40’s.
If you would like to find out more about Presbyopia click here.
