This is the branch of medicine that deals with the disease, anatomical and physiological structure of the eyeball and orbit. A specialist in medical and surgical eye disease is called an ophthalmologist. Defect to the human eye could be congenital or acquired through exposure to some heavy metals or careless exposure to the non-polarized light beam and another unhealthy lifestyle.
Types of Eye Defects
This is a defect of vision in which near objects are seen clearly but far objects appear blurred. The image is focused not on the retina but in front of the retina. This usually occurs when the eyeball is elongated abnormally or when the refractive power of the lens in the eye is very strong. wearing glasses/contacts with concave lenses which helps in focusing the image on the retina can correct myopia.
This is a defect of vision caused by short eyeball or weak refractive power of the eye’s lens. Near object appears blurred but far objects can be seen easily. The image is not focused upon the retina but behind it. Hyperopia can be corrected by wearing glasses/contacts that contain convex lenses.
This defect is when the light rays are distorted and is not a single focal point on the retina, instead of some focus on the retina and some focus in front of or behind it. An irregular curvature of the cornea is the primary cause of this type of defect. A typical symptom of astigmatism is if you are looking at a pattern of lines placed at various angles and the lines running in one direction appear sharp whilst those in other directions appear blurred. The lenses for correcting astigmatism are usually spherically cylindrical in appearance.
Cataracts: Cataract causes the lens to be cloudy, which in turn prevents the formation of a clear, sharp image. When the lens is sealed in a capsule and old dead cells get trapped in the capsule to form cataracts which eventually causes a clouding over of the lens. This clouding results in blurred images.
Age-related macular degeneration (ARMD):
The hardening of the arteries that nourish the retina it’s the major cause of wearing out of the macula. It leads to deprivation of the retinal tissue nutrients and oxygen that are needed for proper function, hence, leading to deterioration of the central vision.
Glaucoma is a disease caused by increased IOP (intraocular pressure) usually resulting from a malfunction in the eye’s drainage system. A persistence IOP can lead to an irreversible damage of the retinal fibres and optic nerve when not treated can cause permanent vision loss.
Treatment and Prevention
In mild cases, glasses are recommended to the patient as a means of correcting or enhancing vision. The types of defect suggest which lens that is recommended. However, most eye problems require the use of surgical means to remove the obstructing film or component from the eye. In most instances where the eyeball is completely broken, artificial eyeball are fixed to fill the orbit of the patient.