Hypermetropia (hyperopia) or long sightedness is the refractive state of the eye wherein parallel rays of light coming from infinity are focused behind the retina with accommodation being at rest thus the posterior focal point is behind the retina, which, therefore,receives a blurred image.
Types of Hypermetropia
There are three clinical types of hypermetropia:
1. Simple hypermetropia is the commonest from. It result from normal biological variation in the development of the eyeball. includes:
• Axial hypermetropia due to congenital/developmental short eyeball,and
• Curvatural hypermetropia due to congenital/developmental flatter cornea.
Simple hypermetropia may be hereditary. Inheritance is usually dominant, which may be irregular.
2. Pathological hypermetropia result due to either congenital or acquired condition of the eyeball which are outside the normal biological variations of the development.
3. Congenital pathological hypermetropia is seen in following conditions:
• Microphthalmos,
• Microcornea,
• Congenital posterior subluxation of the lens,and
• Congenital aphakia.
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