Term | Definition |
biconvex | Consisting of two surfaces that are rounded, elevated, and curved evenly, like part of a sphere. The lens of the eye is a biconvex body. |
choroid ciliary body | Middle, vascular layer of the lens that connects the choroid and iris. It contains ciliary muscles, which control the shape of the lens,and it secretes aqueous humor. |
cone | Photoreceptor cell in the retina that transforms light energy into a nerve impulse. Cones are responsible for color and central vision. |
conjunctiva | Delicate membrane lining the undersurface of the eyelids and covering the anterior eyeball. |
cornea | Fibrous transparent layer of clear tissue that extends over the anterior portion of the eyeball. Derived from Latin corneus, meaning horny, perhaps because as it protrudes outward, it was thought to resemble a horn. |
fovea centralis | Tiny pit or depression in the retina that is the region of clearest vision. |
fundus of the eye | Posterior, inner part of the eye. |
iris | Pigmented (colored) layer that opens and closes to allow more or less light into the eye. The central opening of the iris is the pupil. |
lens | Transparent, biconvex body behind the pupil of the eye. It bends (refracts) light rays to bring them into focus on the retina. |
macula | Yellowish region on the retina lateral to and lightly below the optic disc; contains the fovea centralis, which is the area of clearest vision. |
optic chiasm | Point at which optic nerve fibers cross in the brain (Latin chiasma means crossing). |
optic disc | Region at the back of the eye where the optic nerve meets the retina. It is the blind spot of the eye because it contains only nerve fibers, no rods or cones, and is thus insensitive to light. |
optic nerve | Cranial nerve that carries impulses from the rod and cone cells of the retina to the cerebral cortex in the occipital lobe of the brain. |
pupil | Central opening of the eye, surrounded by the iris, through which light rays pass. It appears dark. |
refraction | Bending of light rays by the cornea, lens and fluids of the eye to bring the rays into focus on the retina. Refract means to break (-fract) back (re-). |
retina | Light-sensitive nerve cell layer of the eye containing photoreceptor cells (rods and cones). |
rod | Photoreceptor cell of the retina essential for vision in dim light and for peripheral vision. |
sclera | Tough, white outer coat of the eyeball. |
thalamus | Relay center of the brain. Optic nerve fibers pass through the thalamus on their way to the cerebral cortex. |
vitreous humor | Soft, jelly-like material behind the lens in the vitreous chamber; helps maintain the shape of the eyeball. |
accommodation | Normal adjustment of the eye to focus on objects from far to near. the ciliary body adjusts the lens (rounding it) and the pupil constricts. When the eye focuses from near to far, the ciliary body flattens the lens and the pupil dilates |
anterior chamber | Area behind the cornea and in front of the lens and iris. It contains aqueous humor. |
aqueous humor | Fluid produced by the ciliary body and found in the anterior chamber. A humor (Latin humidus means moist) is any body fluid, including blood and lymph. |
blephar/o | eyelid |
aque/o | water |
conjunctiv/o | conjunctiva |
conjunctivitis | Commonly called pinkeye. Conjunctivitis occurs when blood vessels dilate from allergens like pollen (allergic conjunctivitis), bacterial infection (bacterial conjunctivitis), or virus (viral conjunctivitis). |
cor/o | pupil |
anisocoria | Anis/o means unequal. Anisocoria may be an indication of neurological injury or disease. |
corne/o | cornea (see kerat/o) |
cycl/o | ciliary body or muscle of the eye |
dacry/o | tears, tear duct (see lacrim/o) |
ir/o, irid/o | iris |
iritis | Characterized by paid, sensitivity to light, and lacrimation. A corticosteroid is prescribed to reduce inflammation. |
iridectomy | A portion of the iris is removed to improve drainage of aqueous humor or to extract a foreign body. |
kerat/o | horny, hard; cornea |
keratitis | Note that kerat/o here does not refer to keratin (protein in skin tissue). |
lacrim/o | tear, tearduct; lacrimal duct |
Lacrimal | Pertaining to tea4rs |
ocul/o | eye |
ophthalm/o | eye |
ophthalmologist | Medical doctor who specializes in treating disorders of the eye. |
ophthalmic | |
opthalmoplegia | Paralysis in one eye. |
opt/o, optic/o | eye, vision |
optic | Nonmedical professional who can examine eyes to determine vision problems and prescribe lenses; a doctor of optometry (OD). |
optician | Nonmedical professional who grinds lenses and fits glasses but cannot prescribe lenses. |
palpebr/o | eyelid |
palpebral | pertaining to the eyelid. |
papill/o | optic disc; nipple-like |
pipilledema | The suffix -edema means swelling. This condition is associated with increased intracranial pressure and hyperemia (increased blood flow) in the region of the optic disc. |
phac/o, phak/o | lens of the eye |
phacoemulsification | Technique of cataract extraction using ultrasonic vibrations to fragment (emulsify) the lens and aspirate it from the eye. |
aphakia | Absence of the lens of the eye. This may be congenital, but most often it is the result of extraction of a cataract (clouded lens) without placement of an artificial lens (pseudophakia). |
pupill/o | pupil |
retin/o | retina |
retinitis | Retinitis pigmentosa is a genetic disorder pigmented scar forms on the retina) that destroys retinal rods. decreased vision and night blindness (nyctalopia) occur. |
hypertensive retinopathy | Lesions such as narrowing of arterioles, microaneurysms, hemorrhages, and exudates (fluid leakage) are found on examination of the fundus. |
scler/o | sclera (white of the eye); hard |
uve/o | uvea; vascular layer of the eye (iris, ciliary body, and choroid) |
vitre/o | glassy |
ambly/o | dull, dim |
amblyopia | reduced vision (poor eyesight) |
dipl/o | double |
glauc/o | gray |
glaucoma | Here, -oma means mass or collection of fluid (aqueous humor). The term comes from the dull gray-green color of the affected eye in advanced cases. |
mi/o | smaller, less |
miosis | Contraction of the pupil.
A miotic is a drug (such as pilocarpine that causes the pupil to contract. |
mydr/o | widen, enlarge |
mydriasis | Widening of the pupil of the eye.
Tropicamide, atropine, and cocaine cause dilation |
nyct/o | night |
nyctalopia | -opia means vision; -al comes from Greek ala, meaning blindness. Night blindness is poor vision at night but good vision on bright days. Deficiency of vitamin A lads to nyctalopia. |
phot/o | light |
photophobia | Sensitivity to light. |
presby/o | old age |
scot/o | darkness |
scotoma | a blind spot. Area of decreased vision surrounded by an area of normal vision; this can result from damage to the retina or the optic nerve. |
xer/o | dry |
xerophthalmia | |
-opia | vision |
hyperopia | Hypermetropia (farsightedness). |
-opsia | vision |
hemianopsia | Absence of vision in half of the visual field. Stroke victims frequently have damage to the brain on one side of the visual cortex and experience hemianopsia ( the visual loss is on the right or the left visual field of both eyes.). |
-tropia | to turn |
esotropia | Inward (eso-) turning of an eye. Exotropia is an outward turning of an eye. These conditions are examples of stabismus (defect in eye muscles so that both eyes cannot be focused on the same point at the same time.) |
astigmatism | Defective curvature of the cornea or lens of the eye. Abnormal curvature of the eyeball so that rays of light are not focused on a single point on the retina. |
hyperopia (hypermetropia) | Farsightedness |
myopia | Nearsightedness; vision for near objects is better than for far. |
presbyopia | Impairment of vision as a result of old age. |
cataract | Clouding of the lens, causing decreased vision. |
chalazion | Small, hard, cystic mass (granuloma) on the eyelid |
diabetic retinopathy | Retinal effects of diabetes mellitus include microaneurysms, hemorrhages, dilation of retinal veins, and neovascularization (new blood vessels form in the retina). |
glaucoma | Increased intraocular pressure results in damage to the retinal and optic nerve with loss of vision. |
Blepharitis | Inflammation of eyelid, causing redness, crusting, and swelling along lid margins. |
Chalazion | Ganuloma formed around an inflamed sebaceous gland. |
Dacryocystitis | Blockage, inflammation, and infection of a nasolacrimal duct and lacrimal sac, causing redness and swelling in the region between the nose and the lower lid. |
Ectropion | Outward sagging and eversion of the eyelid, leading to improper lacrim |
Entropion | Inversion of the eyelid, causing the lashes to rub against the eye; corneal abrasion may result |
Hordeolum (stye) | Infection of a sebaceous gland producing a small, superficial white nodule along lid margin. |
Ptosis | Drooping of upper lid margin as a result of neuromuscular problems or trauma. |
Xanthelasma | Raised yellowish plaque on eyelid cased by lipid disorder (xanth/o = yellow, -elasma = plate) |
hordeolum (stye or sty) | Localized, purulent, inflammatory staphylococcal infection of a sebaceous gland in the eyelid. |
macular degeneration | Progressive damage to the macula of the retina. |
nystagmus | Repetitive rhythmic movements of one or both eyes. |
retinal detachment | Two layers of the retina separate from each other. |
photopsia | bright flashes of light |
floaters | black spots or filmy shapes, which are vitreous clumps that detach from the retina. |
photocoagulation | Making pinpoint burns to form scar tissue and seal holes |
scleral buckle | for large retinal detachments, made of silicone is sutured to the sclera directly over the detached portion of the retina to push the retinal layer together. |
pneumatic retinopexy | A procedure used in retinal detachments, involving a gas bubble that is injected into the vitreous cavity to put pressure on the area of retinal tear until the retina is reattached. |
strabismus | Abnormal deviation of the eye. |
esotropia | Turning inward of one or both pupils; "cross eyes" |
exotropia | one eye turns outward; wall-eyed
Turning to the side or outward of one or both pupils. |
hypertropia | upward deviation of one eye |
hypotropia | downward deviation of one eye |
amblyopia | partial loss of vison or lazy eye |
diplopia | double vision |
fluorescein angiography | Process of recording (viewing and photographing) the circulation of a fluorescein dye through the blood vessels of the retina. |
ophthalmoscopy | Visual examination of the interior of the eye. |
slit lamp microscopy | Examination of anterior ocular structures under microscopic magnification |
visual acuity test | Measurement of clearness of vision; assessed by reading letters of decreasing size on an eye chart. |
visual field test | Measurement of the area (peripheral and central ) Measurement of the area in front of the eye in any part of which an object is seen without moving the eye. |
enucleation | Removal of the entire eyeball |
keratoplasty | Surgical repair of the cornea |
laser photocoagulation | Intense, precisely focused light beam (argon laser) creates an inflammatory reaction that seals retinal tears and leaky retinal blood vessels. |
LASIK | Use of an excimer laser to correct errors of refraction (myopia, hyperopia, and astigmatism. |
phacoemulsification | Ultrasonic vibrations break up the lens, which then is aspirated through the ultrasonic probe. |
scleral buckle | Suture of a silicone band to the sclera over a detached portion of the retina. |
vitrectomy | Removal of the vitreous humor. |
aqueous humor | Watery fluid that circulates through the posterior and anterior chambers of the eye. |
blepharitis | Inflammation of an eyelid. |
blepharoptosis | Prolapse (sagging) of an eyelid. |
conjunctivitis | Inflammation of the conjunctiva. |
anisocoria | Pupils are of unequal size. |
corneal abrasion | Defect in the surface of the cornea. |
cycloplegic | Pertaining to paralysis of the ciliary muscle (causing paralysis of accommodation). |
dacryoadenitis | Inflammation of a lacrimal (tear) gland. |
iritis | Inflammation of the iris. |
iridic | Pertaining to the iris. |
iridectomy | Removal of (a portion of) the iris. |
keratitis | Inflammation of the cornea. |
lacrimal | Pertaining to tears. |
lacrimation | The process of forming tears |
intraocular | Pertaining to within the eye. |
ophthalmologist | One who specializes in the study of the eye, its disorders and treatment. |
ophthalmic | Pertaining to the eye. |
ophthalmoplegia | Paralysis of the eye (muscles). |
optic | Pertaining to the eye or to vision. |
optometrist | One who “measures” (examines) eyes and prescribes lenses. |
optician | One who grinds lenses and fits glasses |
palpebral | Pertaining to the eyelid |
papilledema | Swelling of the optic disc (associated with increased intracranial pressure) and hyperemia (increased blood flow). |
phacoemulsification | Technique of cataract extraction using high-frequency ultrasonic vibrations to remove the clouded lens. |
aphakia | Absence of the lens of the eye. |
pupillary | Pertaining to the pupil. |
retinitis | Inflammation of the retina. |
hypertensive retinopathy | Disease of the retina associated with (secondary to) high blood pressure. |
corneoscleral | Pertaining to the cornea and scleral layers of the eye |
scleritis | Inflammation of the sclera |
uveitis | Inflammation of the uvea (vascular layer of the eye). |
vitreous humor | Clear, watery fluid filling the jelly-like mass (vitreous body) that fills the cavity of the eyeball. |
amblyopia | Dullness of vision (can be caused by poor nutrition, trauma to the eye, or suppression of vision in one eye to avoid diplopia). |
diplopia | Double vision (the perception of two images of a single object). |
glaucoma | Disease of the eye marked by increased intraocular pressure. |
miosis | Condition of contraction of the pupils. |
mydriasis | Condition of enlargement of the pupils. |
nyctalopia | Condition of night blindness |
photophobia | Condition of sensitivity to light. |
presbyopia | Condition of defective vision with advancing age; loss of accommodation. |
scotoma | Area of depressed vision surrounded by area of normal vision (blind spot). |
xerophthalmia | Condition of dry eyes. |
hyperopia | Farsightedness. |
hemianopsia | Condition of absence of vision in half of a visual field. |
esotropia | Condition in which the eyes turn inward. |
acoustic | Pertaining to hearing or sound. |
audiogram | Record of hearing as taken by an audiometer. |
audiologist | Health care professional specializing in the evaluation and rehabilitation of people with hearing loss. |
auditory | Pertaining to hearing. |
aural | Pertaining to the ear. |
postauricular | Pertaining to behind the ear. |
cochlear | Pertaining to the cochlea (spiral-shaped tube in the inner ear). |
mastoiditis | Inflammation of the mastoid process (behind the ear). |
myringotomy | Incision of the eardrum. |
myringitis | Inflammation of the eardrum. |
ossiculoplasty | Surgical repair of a middle ear bone. |
otic | Pertaining to the ear. |
otomycosis | Abnormal condition of a fungal infection in the ear. |
otopyorrhea | Discharge of pus from the ear. |
otolaryngologist | Specialist in the ear and larynx (upper respiratory region). |
salpingopharyngeal | Pertaining to the eustachian tube and the throat. |
stapedectomy | Removal of the stapes bone (middle ear bone). |
tympanoplasty | Surgical repair of the eardrum |
vestibulocochlear | Pertaining to the vestibule and cochlea of the inner ear. This is the 8th cranial nerve (acoustic nerve). |
hyperacusis | Abnormally acute sensitivity to sounds. |
presbycusis | Progressive, bilateral hearing loss occurring with age. |
audiometer | Instrument to measure the sharpness of hearing. |
macrotia | Condition of large ears. |
keratotomy | Incision of the cornea |
Outer Ear | Pinna or auricle, external auditory canal (meatus), Tympanic membrane. |
cerumen | yellowish brown, waxy substance, lubricates and protects the ear. |
Middle Ear | tympanic membrane,(between outer and middle ear) then ossicles; the three small bones, malleus, incus, and stapes...oval window. |
Ossices | Three small bones, malleus, incus and stapes. |
malleus | Hammer-shaped, small bone (ossicle) in the middle ear. |
incus | Small anvil-shaped bone (ossicle) in the middle ear; second ossicle. |
stapes | Small, stirrup-shaped bone in the middle ear; third ossicle |
oval window | separates the middle from the inner ear, is touched by stapes when and as the stapes moves. |
eustachian tube | is a canal leading from the middle ear to the pharynx. |
labyrinth | inner ear, circular, maze-like structure |
perilymph | Special auditory liquids, found in the cochlea of the inner ear, through which vibrations travel. |
endolymph | Special auditory liquids, found in the cochlea of the inner ear, through which vibrations travel. |
organ of Corti | Present in the cochlea of the inner ear, is a sensitive auditory receptor area; in this organ, tiny hair cells receive vibrations from the auditory liquids and relay the sound waves to auditory nerve fibers. |
auditory nerve fibers | Pick the sound vibrations from the auditory liquids and relay them to the auditory center of the cerebral cortex, where impulses are "heard." |
vestibule | Central cavity of the labyrinth, connecting the cochlea and semicircular canals |
Inner Ear | Cochlea, Auditory liquids and receptors in the organ of Corti, Auditory nerve fibers. To Cerebral cortex |
Auditory canal | Channel that leads from the pinna to the eardrum. |
auditory meatus | Auditory canal. |
auditory nerve fibers | Carry impulses form the inner ear to the brain (cerebral cortex). These fibers compose the vestibulocochlear nerve (cranial nerve VIII) |
vestibulocochlear nerve | cranial nerve VIII |
auditory tube | Channel between the middle ear and the nasopharynx; eustachian tube. |
auricle | Flap of the ear; the protruding part of the extyernal ear, or pinna. |
cerumen | Waxy substance secreted by the external ear; also called earwax. |
cochlea | Snail shell-shaped, spirally wound tube in the inner ear; contains hearing-sensitive receptors cells. |
endolymph | Fluid within the labyrinth of the inner ear. |
incus | Second ossicle (bone of the middle ear; incus means anvil. |
labyrinth | Maze-like series of canals of the inner ear. This includes the cochlea, vestibule, and semicircular canals. |
malleus | First ossicle of the middle ear; malleus means hammer. |
organ of Corti | Sensitive auditory receptor area found in the cochlea of the inner ear. |
semicircular canals | Passages in the inner ear associated with maintaining equilibrium. |
stapes | Third ossicle of the middle ear. Stapes means stirrup. |
saccule | Membranous sac (saccule and utricle) contains fluid, endolymph, as well as sensitive hair cells. Located in the semicircular canals |
utricle | Membranous sac (saccule and utricle) contains fluid, endolymph, as well as sensitive hair cells. Located in the semicircular canals |
salping/o | uterine (fallopian) tube; oviduct; auditory (eustachian) |
ot/o | ear |
nyct/o | night |
-tropia | to turn |
tympan/o | tympanic membrane (eardrum); middle ear |
uve/o | uvea, vascular layer of eye (iris, choroid, ciliary body) |
-cusis | hearing |
-meter | measure |
acous/o | hearing |
audi/o | hearing; the sense of hearing |
audit/o | hearing; as in auditory |
aur/o, auricul/o | ear (see ot/o), as in aural |
cochle/o | cochlea |
mastoid/o | mastoid process; the posterior portion of the temporal bone extending downward behind the external auditory meatus. |
Mastoiditis | The mastoid process is the posterior portion of the temporal bone extending downward behind the external auditory meatus. Mastoiditis, cased by bacterial infection, spreads from the middle ear. |
myring/o | eardrum, tympanic membrane (see tympan/o) such as myringotomy or myringitis |
ossicul/o | ossicle |
-otia | ear condition |
macrotia | Abnormally large ears; congenital anomaly. |
acoustic neuroma | Benign tumor arising from the acoustic vestibulocochlear nerve in the brain. |
cholesteatoma | Collection of skin cells and cholesterol in a sac within the middle ear. |
deafness | Loss of the ability to hear |
Meniere disease | Disorder of the labyrinth of the inner ear; elevated endolymph pressure within the cochlea (cochlear hydrops) and semicircular canals (vestibular hydrops). |
otitis media | Inflammation of the middle ear |
Serous otitis media | Noninfectious inflammation of the middle ear with accumulation of clear fluid. |
otosclerosis | Hardening of the bony tissue of the middle ear |
tinnitus | Sensation of noises (ringing, buzzing, whistling, booming) in the ears. |
vertigo | Sensation of irregular or whirling motion either of oneself or of external objects. |
audiometry | Testing the sense of hearing |
audiometer | An audiometer is an electrical device that delivers acoustic stimuli of specific frequencies to determine a patients hearing loss for each frequency. |
cochlear implant procedure | Surgical insertion of a device that allows sensorineural hearing impaired persons to understand speech. |
ear thermometry | Measurement of the temperature of the tympanic membrane by detection of infrared radiation from the eardrum. |
otoscopy | Visual examination of the ear canal with an otoscope. |
tuning fork test | test of ear conduction using a vibration source (turning fork) |
AD | right ear |
AOM | acute otitis media |
AS | left ear (Latin, auris sinistra) |
EENT | eyes, ears, nose, and throat |
ENG | electronystagmography- a test of the balance mechanism of the inner ear by assessing eye movements. |
nystagmus | rapidly twitching eye movements |
ENT | ears, nose, and throat |
ETD | eustachian tube dysfunction |
HEENT | head, eyes, ears, nose, and throat |
PE tube | pressure-equalizing tube-a polyethylene ventilating tube placed in the eardrum (to treat recurrent episodes of acute otitis media) |
SOM | serous otitis media |
dacryoadenitis | Inflammation of tear glands. |
miotic | Drug that causes the pupil of the eye to contract. |
nyctalopia | Night blindness or difficult, poor vision at night. |
retinitis pigmentosa | Inflammation of the retina with pigmentation and progressive scarring of tissue |
tonometry | Measurement of tension and pressure within the eye; glaucoma test. |
suppurative otitis media | Infectious inflammation of the middle ear with pus formation. |