Chapter 13 Medsurg Eye & Ear #1

Romberg test

Ability to perform tasks with eyes open then closed. Client maintains balance with both eyes closed Normal response- maintain balance throughout procedure

Semicircular canal

Associated with balance and equilibrium

Webers test

Determines hearing loss in one or both ears Bone conduction test Place stem of tuning fork (while its vibrating ) in center of the clients head Normal test results- sound is heard equally in both ears

Sclera

Fibrous layer (tunic) The outermost tunic or layer Provides protection & gives shape to the eyeball Thick white opaque connective tissue

Cornea

Fibrous layer(tunic) Central anterior portion of the sclera. Clear, transparent anterior covering. Light enters through it. Most exposed part of the eye, damage can occur.

Accommodation

Focus on objects at various distances During the aging process an individual looses the ability to accommodate

Audio metric testing

Hearing acuity Determines the lowest intensity

Color vision test

Identification of colored patterns on a background of mixed colors May use chart or machine Prerequisite for driving license

Presbyopia

Inability to focus on close objects

Refraction Accommodation Constriction Convergence

Processes that are necessary to form an image

Middle ear

Small air filled chamber located within the temporal bone Oval window, round window, auditory tube, malleus, incus, stapes

Tuning fork test

Two most common tests to determine hearing loss: 1. Webers test 2. Rinne test

Snellen's test (visual acuity)

Used to determine visual status Chart is placed 20 feet from the client Cover one eye while testing the other 20/20 is normal 20/200-Legally blind Used as a screening test The snellen eye chart is read at 20 ft The last line the patient can read with no more than 2 errors is recorded.

Amsler grid test

Used to monitor and diagnose macular problems Look at printed cards with grid lines similar to graph paper. Focus on dot Problems with retina dot will become blurry Check central vision

Choroid

Vascular tunic (layer) *Middle Layer* Rich nutritive blood supply 2 involuntary modified smooth muscle structures located in the anterior portion of the choroid 1) ciliary body (muscle) 2)Iris (flat muscular ring, pigmented)

Posterior chamber

Vitreous humor Transparent jelly-like substance that gives shape to the eye Not constantly replaced Keeps retina attached

Accommodation

What is the process when the lens of the eye changes its curvature to focus on the retina?

Esotropia

When eyes turn inward

Exotropia

When eyes turn outward

Any distortion of the grid

When staring at the black dot on an Amsler grid you should report __

louder in affected ear

You should take into consideration that the Weber test indicates a conductive hearing loss when hearing the tone _____

endolymph and perilymph

_____ conduct sound waves through the inner ear system

Anterior chamber

aqueous humor Being constantly replaced Controls intra-ocular pressure Between cornea and lens helps maintain shape of eye

Lysozyme

bactericidal enyzme found in tears

optic nerve

cranial nerve II Conducts impulses from the eye to the brain and its primary function is vision. Penetrates the sclera at the back of the eye (optic disc or blind spot)

Hyperopia

farsightedness

External auditory canal

Contains cilia Sebaceous glands that secrete cerumen (earwax) Cerumen protects the ear from infection

Parts of eye from the exterior to the most interior

Cornea Aqueous humor iris lens retina choroid

Visual pathway

Cornea Aqueous humor Lens Vitreous humor

vestibule

Deep inside the inner ear past the cochlea Contains receptors that respond to gravity (determine up from down)

anterior chamber & posterior chamber

The lens divides the eye into two chambers ___

3 subdivisions of the inner ear

1- Semicircular canal 2- Vestibule 3- Cochlea

Sclera, Choroid, Retina

3 tissue layers that form the eyeball

Conjunctiva

A thin mucous membrane that lines the inner aspect of the eyelids and the anterior surface of the eyeball. Also extends to the edges of the cornea

tympanic membrane

AKA eardrum Thin, semitransparent membrane that seperates the external ear from the middle ear Transmits sound vibrations to the internal ear

Lens

AKA the crystalline lens Transparent, colorless structure, located behind the pupil Focuses light rays so that they form a perfect image on the retina

Refraction

Bending of light rays

Astigmatism

Blurred vision (light ray is not sharply focused on retina, exact cause is unkown-poss. hereditary tendencies)

Malleus, Incus, Stapes

Bones of the middle ear

pupil

Circular black opening in the iris regulates light that comes in and out

Rinne test

Determines whether hearing loss is sensorineral (sensory nerve) or conductive Are the vibrations heard equally in one ear by placing the tuning fork near the external meatus and the by placing the stem of the tuning fork on the mastoid bone- or are the sound heard longer in one areas as opposed to the other.

Mydriatics

Dilating drops

Auditory tube

Eustachian tube Equalizes pressure on either side of the tympanic membrane Infections can travel easily via mucous membrane from the throat to the middle ear because all areas are lined with a mucous membrane lining

Ophthalmoscopy

Evaluation of underlying structures of the eye To detect abdormalities of the retina, macula, optic disk, and retinal vessels Routine screening test Performed with an instrument called an opthalmoscope Looks at all structures of the eye

otoscopy

Examination of the external acoustic meatus with an otoscope (pulling the ear upward & backward for visualization ) Visualization of the -external auditory canal -typmanic membrane

Sclera

Known as white of the eye (gives shape & protects)

Tonometry test

Measurement of intaocular pressure Normal intraocular pressure is 15-21 mm Hg Used to detect tumors or glaucoma

Refraction test

Measurement of visual acuity to determine refractory errors such as: Myopia Hyperopia Presbyopia Astigmatism

Past-point testing

Measures ability to place a finger accurately on a selected point of the body

Schmirmer test

Measures tear volume within a specific time frame Diagnose dry eyes Numbing drops in eye pull eyelid down Test strip in corner try to produce tears

Convergence

Medial movement of both eyes allows light rays from an object to hit the same point on both retinas

Cornea

Only tissue in the body that can be transplanted from one person to another and is usually not rejected. Immune system is not involved because there are no blood vessels.

Retina

Photooreceptors are located within the __

Cones

Receptors for day vision Three types of cones, each sensitive to a different color (red, green & blue) Color blindness occurs with the absence of the 3 types of cones

Rods

Receptors for night vision and peripheral vision; light & dark no color

Constriction

Regulates the amount of light that enters the eye

Cochlea

Resmembles a snail's shell and contains the organ of corti(organ of hearing) Contains hearing receptors or hair cells C N VIII vestibulocochlear - transmits sound wave messages to the brain

Visual fields test

The area a person can see while looking straight ahead without moving the head. Some conditions such as glaucoma and retinal detachment cause loss of parts of the visual fields

hearing and equilibrium

The inner ear functions in both ____

hearing only

The outer and middle ear structures are involved with _____

20

The patient that has 20/40 vision can see at 40 feet what the normal eye can see at _______ feet

Iris

colored portion of the eye

Retina

inner layer of the eye(3rd layer) Delicate nervous tissue membrane. Located posteriorly but extends anteriorly only to the ciliary body Recieves images and transmits impulses through the optic nerve to the brain.

Vestibular testing

measures balance and equilibrium Types; 1) Romberg test 2) Past point testing

Myopia

nearsightedness