Chapter 5: Diseases and Disorders of the Eye and Ear: Terms Flashcards
occurs when light that enters the eye is focused behind the retina rather than on the retina which requires refocusing by the internal lens or the use of an external corrective lens to reposition the viewed object on the retina to sharpen the image
Hyperopia (Farsightedness)
is the result of light rays entering the eye being focused in front of the retina, causing blurred vision
Myopia (Nearsightedness)
is an irregular focusing of the light rays entering the eye. caused by the corner not being spherical
Astigmatism
is the inability of the internal lens of the eye to focus on near objects due to loss of elasticity of the lens
Presbyopia
is an involuntary, rhythmic movements of one or both eyes
Nystagmus
a visual defect of misalignment, is failure of the eyes to look in the same direction at the same time, which primarily occurs because of the weakness in the nerves stimulating the muscles that control the position of the eye
Strabismus
are acute, focal inflammatory infections of the sebaceous glands of the eyelids
Hordeolum (Stye)
is a small firm, nonmotile, painless, subcutaneous nodule on the margin o body of the eyelid; occur with occlusion of the meibomian glands
Chalazion
inflammation or infection of the cornea
Keratitis
inflammation of the margins of the eyelids involving hair follicles and glands
Blepharitis
the eyelid margins (more often the margin of just the lower lid) turn inward, causing the lashes to rub the conjunctiva
Entropion
the lower eyelid everts from the eyeball, and the exposed surface of the eyeball and the lining of the eyelid become dry and irritated
Ectropion
is a permanent drooping of the upper eyelid, such that it is partially or completely covers the eye
Blepharoptosis
inflammation of the mucous membrane that covers the anterior portion of the eyeball and also line the eyelids
Conjunctivitis
is the painful loss of surface epithelium, or outer layer of the cornea.
Corneal Abrasion or Ulcer