Ear and Eye PP

ophthalmology

science of the eye and its disorders and diseases

ophthalmologist

physician who specializes in diagnosis and treatment of disorders and diseases of the eye

optometrist

not a medical doctor but can perform eye exams, diagnose vision problems and eye diseases, and treat visual defects through corrective lenses and eye exercises

optician

trained to fill prescriptions written by ophthalmologists and optometrists for corrective lenses by grinding the lenses and dispensing eyewear

anatomy of the eye

ocular adnexa

conjunctiva

cornea

lacrimal gland

nasolacrimal duct

layers of the eyeball

ocular adnexa

structures that surround and support the function of the eyeball

conjunctiva

thin mucous membrane that lines eyelid

cornea

covers center of eye

lacrimal gland

located in superior outer portion of eye

nasolacrimal duct

where tears drain into nasal cavity

three layers of eyeball

outermost layer

middle layer

inner layer

outermost layer of eye

sclera

cornea

middle layer of eyeball

choroid

iris

ciliary body

inner layer of eyeball

lens

retina

visual impulse begins with

light passing through the cornea

cornea refracts the light and

passes it through the aqueous humor and pupil into the lens

ciliary muscle adjusts the curvature of lens

to again refract light rays

rays pass into retina and

trigger photo-receptive cells of rods and cones

light energy converts into an electrical impulse and

is sent through the optic nerve to the brain

refraction

the ability of the lens of the eye to bend parallel light rays coming into the eye so that the rays are focused simultaneously on retina

hyperopia

farsightedness

when light enters the eye and focuses behind retina, causing difficulty seeing objects that are close

myopia

nearsightedness

when light rays entering eye focus in front of retina, causing objects at a distance to appear blurry and dull

presbyopia

changing the point of focus from distant to near becomes difficult, due to age

difficulty seeing at reading level

astigmatism

occurs when light rays entering the eye are focused irregularly

occurs because cornea or lens is not a smooth sphere, but has an irregular shape

corrected with glasses, contacts, or surgery

signs and symptoms of refractive errors

squinting

frequent rubbing of eyes

headaches

treatment of refractive errors

eyeglasses; problems with shape of lines can be corrected surgically

strabismus

eyes do not track together (do not look in same direction)

in children, caused by weakness in eye muscles

nystagmus

constant, involuntary movement of one/both eyes

accompanied by blurred vision

caused by an abnormal function in part of the brain that controls eye movements

hordeolum (stye)

localized purulent infection of sebaceous gland of eyelid

chalazion

small cyst from blockage of meibomian gland

keratitis

inflammation of cornea

results in superficial ulcerations

conjunctivitis

inflammation of conjunctiva caused by irritation, allergy, or bacterial infection

blepharitis

inflammation of glands and lash follicles along eyelids

corneal abrasion

caused by foreign body or direct trauma

corneal abrasion diagnosis is confirmed by

fluorescein stain highlighted by cobalt blue light

corneal abrasion

foreign bodies are removed first, then treated with antibiotic ointment and nonsteroidal antiinflammatory ophthalmic ointments

cataract

cloudy area blocks passage of light into retina

blurred, dimmed vision

effective treatment is surgical removal of lens

cataracts may result from

eye injury

exposure to extreme heat or radiation

inherited factors

usually due to aging

glaucoma

common and serious, increased intraocular pressure

damages optic nerve and causes blindness if untreated

tonometer and gonioscopy used to diagnose

miotic and beta-blocker eye drops or surgery for treatment

diabetic retinopathy

lack of blood flow due to diabetes mellitus

macular degeneration

progressive deterioration of macula lutea

causes severe vision loss and blindness

no cure but antioxidants may prevent or slow progression

macular degeneration two forms

dry- 90% of cases

wet

anatomy of ear

outer/external ear

middle ear

inner ear

outer/external ear

auricle/pinna

external auditory canal

tympanic membrane

middle ear

air-filled cavity that contains 3 tiny bones called ossicles

tympanic membrane seals off outer ear from middle ear

ossicles

malleus

incus

stapes

inner ear

labyrinth

divided into cochlea and semicircular canals

semicircular canals and vestibule function to maintain equilibrium

semicircular canals detect dynamic equilibrium

repetitive or excessive stimulation to equilibrium receptors may cause people to feel nauseous

hearing starts with soundwaves

reaching tympanic membrane

tympanic membrane vibrates and

ossicles transmit waves to oval window

organ of Corti contains

receptors for sound

eighth cranial nerve transmits

auditory impulse to the medulla oblongata

conductive hearing loss

caused by a problem that originates in the external or middle ear

sensourineural hearing loss

results from an abnormality of the organ of Corti or of the auditory nerve

otitis externa/swimmer’s ear causes

dermatologic conditions

trauma

continuous use of earplugs/earphones, swimming

otitis media

serous or suppurative

often associated with upper respiratory tract infection or allergic reaction

more common in children

cerumen

soft yellowish waxy substance that lubricates the external auditory canal

excessive secretion of cerumen can cause

hearing loss

tinnitus

feeling of fullness

otalgia

impacted cerumen can cause

conductive hearing loss

ménière’s disease

causes swelling and edema in the semicircular canals

triggers episodes of recurring attacks of vertigo, tinnitus, a sensation of pressure in the affected ear, and advancing hearing loss

ophthalmoscope

used to examine interior of eye

helpful for detecting disorders of eyes and certain systemic disorders

eyelids are examined for

edema

pupils of eyes are normally

round and equal

a light is shone into one eye

called the light and accommodation L&A

slit lamp biomicroscope

used to view fine details in anterior segments of the eye

PERRLA

pupils

equal

round

reactive to

light and

accommodation

distance visual acuity

best single test for vision screening

used with Snellen alphabetical chart

vision test patients must be able to

view the chart at eye level from a distance and chart should be illuminated with maximum light

because this is a gross screening of visual acuity

patients are usually allowed to use glasses or contacts

document use of corrective lenses

result of each eye separately and as fractions

outcomes of each test with appropriate abbreviations

near visual acuity

patient holds card with varying font size 14-16 in from face

test each eye, other eye covered but open

document number at which the patient stopped reading for each eye, whether corrective lenses were worn, and any signs of eye strain like squinting

ishihara color vision test

tests for defects in color vision (congenital or acquired)

assess perception of primary colors and shades of colors

polychromatic plates with numbers of one color, and background dots are different color

if score is 10 or higher, patient is within average range

eye irrigation

use sterile technique and equipment to avoid contamination

used to relieve inflammation, remove drainage, dilute chemicals, or wash away foreign bodies

never attempt to remove foreign body with applicator

instillation of medication to treat infection, soothe irritation, anesthetize eye, dilate pupils

eye drops or ointments are common

aseptic procedures in ophthalmology

avoid contamination of eye medication applicators

sterility of medications is critical

view external auditory canal with

otoscope covered by a disposable plastic ear speculum

a normal otoscopic examination reveals an

external auditory canal with a small amount of cerumen and a pearly gray and concave tympanic membrane

assess hearing acuity

tuning fork

quantitative and qualitative audiometric testing

questions for gathering a history of ear problems

are you experiencing nausea, vomiting, dizziness, ear pain, fever, headache, upper respiratory infection, ringing of ears, drainage, loss of balance, or hearing loss?

what are the onset, duration, and frequency of symptoms?

have you taken any medications for the symptoms? If so, what medication? Has it helped?

Do you have the problem in both ears?

Are you experiencing pain? On a scale of 1 to 10, with 10 being the worst pain, how would you rate the pain? Is it localized or radiating, in one ear or both?

Has anything you have tried relieved the symptoms?

audiometric testing

measures the lowest intensity of sound an individual can hear

wearing headphones, the patient is exposed to sounds and is asked to signal when a sound is heard

if initial screening indicates hearing deficit, an audiologist may be consulted

ear irrigation

done to remove excessive or impacted cerumen, to remove a foreign body, or to treat inflamed ear with an antiseptic solution

administer irrigating solution with applicator tilted up, toward top of external canal

always chart the treatment and its results immediately after completion

instilling otic medications

medication ordered for ear instillation is given to soften impacted cerumen, to relieve pain, or as an antibiotic drop for an infectious pathogen