Eye Disorders + Ear Terms/Enrichment — 101–126

diabetic retinopathy

Degenerative changes in the retina associated with diabetes mellitus

glaucoma

An eye disease caused by increased intraocular pressure that damages the optic disk and causes vision loss; usually results from faulty fluid drainage from the anterior eye

hyperopia

A refractive error in which light rays focus behind the retina and objects can be seen clearly only when far from the eye; farsightedness; also called hypermetropia

myopia

A refractive error in which light rays focus in front of the retina and objects can be seen clearly only when very close to the eye; nearsightedness

phacoemulsification

Removal of a cataract by ultrasonic destruction and extraction of the lens

presbyopia

Changes in the eye that occur with age; the lens loses elasticity and the ability to accommodate for near vision

retinal detachment

Separation of the retina from its underlying layer

ophthalmia neonatorum

Severe conjunctivitis usually caused by infection with gonococcus during birth

trachoma

An infection caused by Chlamydia trachomatis leading to inflammation and scarring of the cornea and conjunctiva; a common cause of blindness in underdeveloped countries

decibel (dB)

A unit for measuring the relative intensity of sound

hertz (Hz)

A unit for measuring the frequency (pitch) of sound

mastoid process

A small projection of the temporal bone behind the external auditory canal; it consists of loosely arranged bony material and small, air-filled cavities

labyrinthitis

Inflammation of the ear's labyrinth (inner ear); otitis interna

mastoiditis

Inflammation of the air cells of the mastoid process

audiometry

Measurement of hearing

otoscope

Instrument for examining the ear (see FIG. 3-11B)

diopter

A measurement unit for the refractive power of a lens

amblyopia

A condition that occurs when visual acuity is not the same in the two eyes in children; also called "lazy eye"

anisocoria

Condition in which the two pupils (root: cor/o) are not of equal size

floater

A small moving object in the field of vision that originates in the vitreous body; floaters appear as spots or threads and are caused by deposits in the vitreous body that cast a shadow on the retina

retinitis

Inflammation of the retina; causes include systemic disease, infection, hemorrhage, exposure to light

retinoblastoma

A malignant glioma of the retina; usually appears in early childhood and is sometimes hereditary; fatal if untreated, but current cure rates are high

scotoma

An area of diminished vision within the visual field

xanthoma

A soft, slightly raised, yellowish patch or nodule usually on the eyelids; occurs in the elderly; also called xanthelasma

enucleation

Surgical removal of the eyeball

keratometer

An instrument for measuring the curvature of the cornea