What is hypermetropia?
Hypermetropia is a common vision disorder. Also known as hyperopia or long sightedness, it results from the overall power of the eye not being strong enough, or the length of the eye being too short. This means that the rays of light that enter the eye fall behind the retina rather than falling on the retina in focus. Hypermetropia can result in blurred vision, primarily at near distance, but depending on its severity it can also affect distance vision.
Hypermetropia symptoms and signs
People with hypermetropia may suffer from:
- Eye strain
- Blurred vision
- in some instances, squints (eye turning).
These signs and symptoms are worse when conducting near vision tasks like reading, and may be intermittent. Hypermetropia symptoms can manifest themselves during periods when the patient is doing lots of close work, for example, during exam periods for school children. In the short term, the visual system can compensate for small amounts of long sightedness but this can become problematic if effort is exerted over prolonged periods of time.
Who is affected by hypermetropia?
Hypermetropia is a common condition that can occur at any age. However, because hypermetropia is caused by the eye being too short or the optical components of the eye not being strong enough, it is quite common for children to have small degrees of long sightedness that they may grow out of over time as their eyes grow longer.
How is hypermetropia diagnosed?
Hypermetropia can be diagnosed by an optometrist during a routine eye examination, and common forms of vision correction can be prescribed to alleviate symptoms. Positive lenses are prescribed to increase the overall power of the eye, reduce the amount of effort the visual system is exerting to overcome any hyperopia present, and alleviate any manifest symptoms that the patient is suffering from as a result.
Eye prescriptions usually involve several numbers. The figure that is relevant to hypermetropia is Sphere (sometimes abbreviated to Sph). This describes how strong your lenses should be, and is measured in dioptres (D for short). A positive number, for example, 1.5D, indicates hypermetropia. (Negative numbers indicate short-sightedness or myopia). The more severe the long sightedness, the further away your Sphere prescription will be from zero. So 0.5 D would denote a mild case of hypermetropia, whereas 6D would be severe.
Hypermetropia treatment options
Hypermetropia can be treated with corrective contact lenses or spectacles. Alternatively, eye surgery is an option that can be very effective for suitable candidates.
- Traditional correction: glasses or contact lenses in the form of positive lenses.
- Surgical correction: The two surgical procedures available are Laser Eye Surgery and Clear Lens Extraction. The latter is the same as cataract surgery but involves the removal of a clear crystalline lens (with no cataract).
If your hypermetropia treatment of choice is surgical correction, it is important to talk through your choice with your eye surgeon. There are many factors to consider, including your age, how severe your hypermetropia is, the thickness of your corneas and whether you have any other eye conditions.