Ametropia
Ametropia is a general term used to refer to any abnormality of refraction in the eye. This may be experienced as blurred vision.
Compare and contrast:
- In cases of normal vision, light enters the eye then passes through the cornea (which refracts light), then the aqueous humour, then the pupil, then the lens (that further refracts the light, focussing it into an image on the retina). This situation is called "emmetropia".
- In cases of ametropia, the overall process does not refract (that is, "bend" or "re-direct") light from the object being viewed to exactly the ideal extent necessary to form a clear sharp image on the retina at the back of the eye.
While ametropia is a general term for abnormal refraction through the eye, there are also many specific terms describing particular ways in which refraction through the eye is abnormal, including:
- Astigmatism,
- Hypermetropia, and
- Myopia.
More about Ophthalmology:
This section includes short definitions
of many diseases, disorders, and conditions of the eyes and visual system.
For definitions of other terms in this category, choose from the list
to the left (but note that this is not a complete/exhaustive list).
Other related pages include
- A diagram of the eye
- Definitions and descriptions of the parts of the eye
- A concise description of the human retina
- Definitions of parts of the retina
- Clinical and surgical procedures re. eyes and human visual system
For further information see also our pages of books about ophthalmology.