Question | Answer |
Abrasion | Scraped area of corneal surface accompanied by loss of superficial tissue. |
Accomodation | The ability of the crystalline lens to adjust power to provide retinal focus of images of objects closer than infinity. |
Acuity | Measure of an eyes ability to distinguish object details and shape. Assessed by the smallest identifiable object that can be seen at a specified distance (usually 20 ft or 16 in) |
Adnexia Oculi | Structures surrounding the eyeball, includes the eyelids, eyebrows, tear drainage system, orbital walls, and orbital contents |
Albinism | Lack of pigment in the iris and choroid, results in reddish pupils and iris; usually accompanied by poor vision, light sensitivity, and involuntary oscillating eye movements |
Amblyopia | Loss of vision without any apparent disease of the eye; decreased vision without detectable anatomical damage to the retina on visual pathways. |
Ametropia | A refractive error in which the eye, when in a state of rest, does not focus the image of an object upon the retina. Includes hyperopia, myopia, and astigmatism. |
Aniridia | (Iris hypoplasia); Incomplete formation of the iris; associated with glaucoma, nystagmus, sensitivity to light, and poor vision |
Aniseikonia | Unequal retinal image sizes in the two eyes, usually from different refractive errors |
Anisicoria | Unequal pupil size (difference of 1 mm or more) |
Anomaly | A deviation from normal, especially of a body part |
Anophthalmia | Absence of the eyeball |
Anterior Chamber | Fluid-filled space inside the eye between the iris and the innermost corneal surface. |
Antigen | Any substance that stimulates production of antibodies; part of the immune system. |
Aphakia | Absence of the eyes crystalline lens. |
Aqueous Humor | Clear, watery fluid that fills the space between the back surface of the cornea and the front surface of the vitreous, bathing the lens. Produced by the ciliary processes; nourishes the cornea, iris, and the lens and maintains intraoccular pressure. |
Arcus Senilis | Ring-shaped, grayish deposit of fat near the limbus. Typically occurs after age 60, or in young patients with abnormally high blood fat levels. |