Med Term: Chapter 11 (nervous system and mental illness)

Set of flashcards focusing on ocular anatomy and related disorders.

Bony cavity of skull that contains and protects the eyeball and associated muscles, blood vessels, and nerves.

Orbit

Structures outside the eyeball.

Adnexa

Allow for wide range of precise eye movements.

Eye muscles

Coordination of eye muscles allowing for depth perception.

Binocular vision

Ability to see things in three dimensions.

Depth perception

Angle where upper and lower eyelids meet.

Canthus

Small hair making up eyebrows/eyelashes.

Cilia

Framework within upper and lower eyelids providing necessary stiffness and shape.

Tarsus

Transparent mucous membrane lining underside of the eyelid protecting the exposed surface of the eyeball.

Conjunctiva

includes structures producing, storing, and removing tears.

Lacrimal apparatus

Located on underside of upper eyelid just above outer corner of each eye.

Lacrimal gland

Maintains moisture on the anterior surface of eyeball.

Lacrimal fluid

Ducts at the inner corner of each eye; ducts collect tears emptying them into lacrimal sacs.

Lacrimal canal

Enlargement of the upper portion of the lacrimal duct.

Lacrimal sac

Passageway draining excess tears into nose.

Lacrimal duct

Pertaining to the eye.

Ocular

Outside the eyeball.

Extraocular

Within the eyeball.

Intraocular

White of the eye; maintains shape of eye; protects delicate inner layers of tissue.

Sclera

Opaque middle layer of eyeball; provides blood supply to the entire eye.

Choroid

Innermost layer lining posterior segment of the eye; receives nerve impulses and transmits them to the brain via optic nerve.

Retina

Front one-third of eyeball; located behind the cornea and in front of the iris.

Anterior segment

Remaining two-thirds of the eyeball; located behind the iris and in front of the ligaments holding the lens in place that lines with the retina

Posterior segment

Black and white receptors.

Rods

Color receptors.

Cones

Light-sensitive area in the center of the retina; responsible for sharp central vision.

Macula

Pit in the middle of the macula; high concentration of cones allows for the best color vision.

Fovea centralis

Where nerve endings of the retina enter optic nerve; blind spot; contains no rods or cones.

Optic disk

Transmits nerve impulses from retina to the brain.

Optic nerve

Pigmented layer of eye; rich blood supply; consists of choroid, ciliary body, and iris. (structure of the retina)

Uvea

Set of muscles and suspensory ligaments that adjust thickness of the lens and refine the focus of light rays on retina.

Ciliary body

Colorful circular structure surrounding the pupil; muscles control the amount of light entering through the pupil.

Iris

Transparent outer surface of eye covering iris and pupil; focuses light rays entering the eye.

Cornea

Black circular opening in the center of the iris permitting light to enter the eye.

Pupil

Clear, flexible, curved structure contained within clear capsule located behind the iris and pupil; focuses images on the retina.

Lens

Eye adjustment for the vision at varying distances.

Accommodation

Simultaneous inward movement of eyes toward each other; allows maintenance of single binocular vision as object comes nearer.

Convergence

Bending of light rays to focus on the retina.

Refraction

Ability to distinguish object details and shape at a distance.

Visual acuity

Specializes in diagnosing/treating diseases/disorders of eyes.

Ophthalmologist

Provides diagnosis of eye diseases, measuring accuracy of vision determining need for corrective lenses.

Optometrist

Health care practitioner who designs, fits, and dispenses lenses for vision correction.

Optician

Drooping of upper eyelid.

Ptosis

Nodule or cyst related to obstruction in sebaceous gland.

Chalazion

Swelling of eyelid, near eyelash follicles.

Blepharitis

Turning outward of eyelid.

Ectropion

Turning inward of eyelid.

Entropion

Pus-filled lesion on the eyelid due to acute infection in sebaceous gland.

Hordeolum

Swelling of tissue surrounding the eye(s).

Periorbital edema

Inflammation of conjunctiva.

Conjunctivitis

Inflammation of lacrimal gland.

Dacryoadenitis

Bleeding between conjunctiva and sclera.

Subconjunctival hemorrhage

Dry eye due to decreased production of tears.

Xerophthalmia

Inflammation of uvea.

Uveitis

Form of uveitis affecting structures in the front of the eye.

Iritis

Injury to outer layers of cornea.

Corneal abrasion

Pitting of cornea due to infection or injury.

Corneal ulcer

Inflammation of cornea.

Keratitis

Irregular, cone-shaped cornea leading to distortion of vision.

Keratoconus

Inflammation of sclera.

Scleritis

Unequal size of pupils.

Anisocoria

Loss of transparency of lens causing progressive loss of visual clarity.

Cataract

Particles of cellular debris in vitreous humor casting shadows on the retina, may be an indication of retinal detachment

Floaters

Appearance of flashes of light.

Photopsia

Contraction of pupil in response to light.

Miosis

Dilation of pupil.

Mydriasis

Involuntary, constant, rhythmic movement of eyeball.

Nystagmus

Swelling and inflammation of the optic nerve.

Papilledema

Separation of some or all of the retina from the choroid.

Retinal detachment

Progressive degeneration of retina affecting night and peripheral vision.

Retinitis pigmentosa

Group of diseases characterized by increased intraocular pressure.

Glaucoma

More common form; asymptomatic until optic nerve damage.

Open-angle glaucoma

Narrowing of area between cornea and iris resulting in decreased fluid to trabecular meshwork. Lack of treatment leads to blindness in as little as 2 days

Closed-angle glaucoma

Progressive condition causing damage to macula that results in the loss of central vision

Macular degeneration

Type of macular degeneration.

Dry macular degeneration

Type of macular degeneration.

Wet macular degeneration

Perception of two images of a single object.

Diplopia

Difficulty seeing at night.

Nyctalopia

Blindness in one-half of the visual field.

Hemianopia

Inability to distinguish certain colors.

Monochromatism

also known as auricle, the external portion of the ear that captures sound waves and transmits them into external auditory canal

Pinna

Eardrum Located between outer and middle ear, (Membrane transmits sound by vibrating)

Tympanic

Three small bones in middle ear that transmit sound waves from eardrum to inner ear by vibration

Auditory Ossicles

Hammer-shaped ossicle.

Malleus

Anvil-shaped auditory ossicle

Incus

Stirrup-shaped ossicle.

Stapes

spiral/Snail-shaped structure where sound vibrations are converted into nerve impulses

Cochlea

Central part of inner ear.

Vestibule

Contains endolymph and sensitive hair cells that bend in response to the movements of head and assist with equilibrium

Semicircular canals

Transmits sound signals to brain.

Auditory nerve

Inflammation of middle ear.

Otitis media

Inflammation of outer ear.

Otitis externa

Ringing in the ears.

Tinnitus

Sensation of spinning.

Vertigo

Problem conducting sound waves.

Conductive hearing loss

Damage to inner ear or nerve.

Sensorineural hearing loss

Age-related hearing loss.

Presbycusis

Disorder of inner ear causing vertigo.

Meniere disease

Inflammation of inner ear (May result in vertigo and deafness)

Labyrinthitis

Surgical repair of eardrum.

Tympanoplasty