The eye is a complex organ made up of several highly specialized components. Many eye disorders do not threaten sight, but a few serious conditions may damage the eye’s components and lead to loss of vision. Eye disorders are very common, but early diagnosis usually leads to successful treatment.
This section covers disorders caused by disease, structural abnormality, or injury to the eye. Conditions that involve the front covering of the eye (the conjunctiva and cornea) are described first, followed by disorders that affect the front chamber of the eye and the structures within it, including the iris and lens.
The next group of articles discusses disorders of the light-sensitive retina at the back of the eye and conditions affecting the optic nerve, which carries nerve signals from the retina to the brain. The final articles in this section cover conditions in which the eye is displaced or injured in some way. Impaired vision, whether occurring in healthy eyes or as a consequence of serious underlying causes, is described separately (see Vision disorders), as are disorders of the eyelid and tear system and eye disorders that usually or only affect children. These include congenital blindness, cancer of the retina (see Retinoblastoma), and misalignment of the gaze of the eyes (see Strabismus).
Many major eye disorders that in the past would have ultimately progressed to blindness can now be treated successfully if detected early. For example, diabetic retinopathy is often now treated by laser surgery to prevent further sight loss. Regular eye examinations are therefore important, especially for people over the age of 40.
For more information on the structure and function of the eye, see Eyes and Vision.
From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.
The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.