Introduction to the Sensory System

Practice flashcards covering the anatomy, physiology, assessment, and diagnostic studies of the eye and ear based on the Introductory Medical-Surgical Nursing curriculum.

Eyeballs

Globes located in a protective bony cavity or orbit of the skull.

Canthus

The location where the eyelids meet; usually horizontal unless affected by conditions like Down syndrome.

Blinking

A function that clears dust and particles from the eye surface.

Tears

A fluid composed of water, sodium chloride, and lysozyme.

Sclera

The white of the eye that protects internal structures and connects to the cornea, anterior chamber, and pupil.

Uvea

The vascular coat of the eye, which includes the choroid, iris, pupil, aqueous humor, and vitreous humor.

Posterior chamber

A section of the eye that maintains the shape of the eyeball and contains the retina, rods, cones, and macula.

Rods and cones

Photoreceptors located in the retina of the eye.

Cataract

An opaque lens that results in blurred or cloudy images.

Snellen eye chart

A tool used to determine visual acuity.

Jaeger chart

An assessment tool for testing near vision, alongside the Rosenbaum Pocket Vision Screener.

Ishihara polychromatic plates

A diagnostic tool used to assess color vision.

Corneal light reflex test

A test used to check eye alignment.

Cover–uncover test

A diagnostic test for extraocular muscle function.

Positions test

An assessment used to evaluate eye muscle strength and cranial nerve function.

Ophthalmoscopy

An examination of the fundus of the eye.

Retinoscopy

The assessment of the focusing power of each eye.

Tonometry

The measurement of intraocular pressure, with methods including applanation, indentation, and noncontact.

Normal Intraocular Pressure (IOP)

A pressure range measured between $10$ to $21\,mm\,Hg$.

Amsler grid

A diagnostic tool used to identify macular problems.

Slit-lamp examination

A test that magnifies the eye surface to identify corneal abrasions, iritis, cataracts, or conjunctivitis.

Retinal angiography

A study used to identify vascular changes and assess blood flow.

Outer ear (Auricle)

A subdivision of the ear that includes the pinna, external acoustic meatus, and tympanic membrane.

Middle ear

A subdivision of the ear containing the eustachian tubes, malleus, incus, and stapes.

Inner ear (labyrinth)

A subdivision of the ear containing the cochlea (hearing), semicircular canals (balance), and vestibulocochlear nerve (Cranial Nerve $VIII$).

Whisper test

A test used to assess gross auditory acuity.

Rinne and Weber tests

Tuning fork tests used to identify conductive or sensorineural hearing loss.

Romberg Test

A test used to assess a client's ability to sustain balance.

Audiometry

A precise measurement of hearing acuity recorded in decibels ($dB$).

Auditory perceived sound thresholds

The lowest perceptible sound is $20\,dB$ and the painful sound level is $120\,dB$.

Caloric stimulation test

A test that measures the vestibular reflexes of the inner ear by inducing nystagmus.

Electronystagmography

A diagnostic test used in conjunction with caloric stimulation to measure the duration and velocity of eye movements during nystagmus.