Ch 8: Sensory System - The Ear, Nose, Throat

Ear

sensory organ that aids in hearing and maintaining equilibrium

Nose

olfactory organ enabling the passage of air into the lungs, made of nostrils (anterior naris) and inferior concha in nasal cavity

Throat

acts as the passage of air, food, and fluids

in the anterior portion of the neck, contains pharynx and larynx

Otorhinolaryngology (ENT)

the study of the ear, nose, and throat

What are the main parts of the external ear?

pinna, external auditory canal, ceruminous glands

Pinna

external visible part of ear, made of auricle and external auditory canal

External Auditory Canal

S-shaped tube extending from the auricle to the eardrum (tympanic membrane)

Auricle

conveys captured sound waves to auditory canal

What structures do the skin lining of the external ear possess?

hair follicles, nerve endings, ceruminous glands

Ceruminous Glands

secrete cerumin

Cerumen

secreted waxy substance that protects the inner ear structure from foreign particles, helps lubricate auditory canal

What are the main components of the middle ear?

tympanic cavity, malleus, incus, stapes, eustachian tube

Tympanic Cavity

air-filled chamber extending from tympanic membrane, has a thin tissue covering that separates external ear from middle ear

conducts sound waves and transmits to bony ossicles in oval window

Malleus, Incus, and Stapes

tiny bony ossicles interconnected to each other across the middle ear

Eustachian Tube

connects to nasopharynx and opens into middle ear, helps maintain equal pressure inside and outside ear

What are the main components of the inner ear?

cochlea, semicircular canals joined by vestibules, organ of Corti

Cochlea

spiral-shapes part of inner ear that contains the organ of Corti

Organ of Corti

made of hair-like sensory cells surrounded by sensory nerve fibers, converts sound vibrations to electrical signals to be sent to the brain

Semicircular Canals

help evaluate the position of the head relative to the pull of gravity and maintain balance

Motion Sensitivity/Sickness

repetitive or excessive stimulation of equilibrium receptors that cause nausea or vomiting

Describe the passage of sound as it travels through the ear

auricle captures and directs sound through external auditory canal and to the middle ear, hits tympanic membrane and sound vibrations are sent to oval window, malleus/incus/stapes vibrate, nerve cell endings in organ of Corti are stimulated via those vibrations, sound transmitted to cochlear nerve and into the brain so we perceive sound

What are the major causes of disorders of the ENT?

structural abnormalities

What are two of the main causes/types of hearing loss?

conduction problems and sensorineural problems

Conduction Problems

sound waves within the ear are affected, causing hearing loss

include abnormalities in external or middle ear (preventing sound passage), conditions limiting tympanic membrane vibration, conditions interfering with middle ear bone-conducted sound passage

Sensorineural Problems

hearing loss related to the inner ear or auditory nerve

include abnormalities in the organ of Corti and auditory nerve problems

Presbycusis

reduction in the number of receptor cells in the organ of Corti, type of hearing loss that affects people as they age

Mixed Hearing Loss

combination of conductive and sensory deafness

What are some other potential causes of hearing loss?

impacted cerumen, trauma to tympanic membrane (especially with scar formation), hemorrhage or fluid in middle ear

Otitis

infection of the ear

Otitis Externa (Swimmer’s Ear)

infection of the external ear due to dermatologic conditions (e.g. seborrhea, psoriasis), trauma to the canal, or continuous use of earplugs/earphones

Otitis Media

middle ear inflammation resulting in fluid accumulation behind the tympanic membrane, fluid is either serous or suppurative

What are some risk factors of developing otitis media?

family history, premature birth, seasonal allergies, underlying disease

Impacted Cerumen

condition where excessive secretion of cerumen blocks the ear canal, resulting in a feeling of fullness, ear pain, tinnitus, or conductive hearing loss

Meniere’s Disease

chronic, progressive disease characterized by recurrent attacks of vertigo, tinnitus, pressure sensation in affected ear, and advanced hearing loss

involves ths semicircular canals, causing swelling and edema in the endolymphatic sac

Endolymphatic Sac

responsible for filtering and excreting endolymph

What are some commonly known illnesses that can affect the ENT?

common cold, allergies (both causing changes in nasal and oral mucosa), and group A beta-hemolytic streptococcal bacteria that can cause strep throat

Otoscope

used to examine auditory canal (covered with ear speculum to prevent transfer of disease)

What is a normal finding in the ear when using an otoscope?

seeing an external auditory canal with little cerumen and a pearly gray and concave tympanic membrane

Tympanogram

determines air pressure of the middle ear and mobility of tympanic membrane

Tuning Fork and Audiometric Testing

both used to test hearing acuity if hearing loss is suspected

What questions should an MA ask to get complete medical history regarding hearing ability/disease?

Are you experiencing pain? Any history of ear conditions? Is the problem in both ears? What medications have you taken for your symptoms?

What are some ear infection risks?

exposure to second-hand smoke, pacifier use beyond 6 months, exposure to large-group childcare settings

Tuning Fork Testing

assesses hearing through air and bone conduction

What is the most commonly used tuning fork frequency?

512 hertz (Hz)

Describe the general process of a provider performing a tuning fork test

holds fork by the stem, softly strikes tines on palm of hand to activate, positions fork according to test type performed

Weber Test

vibrating fork placed midway at top of head, test if patient reports hearing is better in one ear than the other

Rinne Test

compares air conduction sound with bone conduction sound, patient raises hand when sound disappears, then form inverted to ensure vibrating tines are about 1 inch in front of external ear canal

If there is no abnormality during a tuning fork Rinne test, then…

the patient hears the sound when the fork is placed in front of the canal

Audiometric Testing

measures lowest intensity of sounds a person can hear, usually done by specially trained MA, doe manually or automated model

Audiogram

results of audiometric test charted on this graph

Describe the general procedure of an audiometric test

1. sanitize hands, assemble equipment

2. ensure testing done in a quiet area

3. identify patient and introduce self

4. explain sounds of various intensities will be provided through headphone, patient must raise hand/push button upon hearing sound

5. place headphones and adjust for comfort

6. start transmitting lowest to highest frequency, gradually increasing, mark left ear X and right ear O

7. test each ear separately

8. hand results to provider, download to health record

9. sanitize and disinfect equipment

10. sanitize hands

Ear Irrigation

flushing the ear with fluids (e.g. water, prescribed meds) to help remove foreign body, remove excessive/impacted cerumen, treat inflammation with antiseptic solution

Describe the general procedure of an ear irrigation

1. sanitize hands

2. confirm provider’s orders, gather equipment

3. check solution label 3x to prevent med errors

4. prepare solution as directed, store at room temp.

5. identify patient, explain procedure

6. use otoscope to locate impaction

7. instruct patient to sit with head tilted toward affected ear, place water-absorbent towel over poly-lined barrier on patient’s shoulder, collecting basin on towel at base of ear

8. wear gloves, wipe any particles from outside ear with gauze

9. fill syringe with solution, expel any air

10. straighten external ear canal, place syringe tip in meatus of ear (older than 3 years = pull pinna up and back, younger than 3 years = pull earlobe down and back)

11. direct solution flow slowly toward rood of external auditory canal, continue until material removed

    1. tilt applicator up toward top of canal to not hit tympanic membrane

12. use gauze to dry patient’s external ear, inspect with otoscope to determine results

13. place clean absorbent towel on exam table, let patient rest with head turned to irrigated side

14. document procedure in record

What are otic medications commonly used for?

soften impacted cerumen before irrigation, relieve pain, act as antibiotic drop to treat middle and external ear infections, relieve Meniere’s disease nausea and vomiting

What are some commonly used otic medications?

cerumenolytics, otic anesthetics, otic antiinfectives, otic steroids

Myringotomy

surgical procedure used to drain fluid in tympanic membrane

What are some other treatment options for ear issues?

surgical, implantation, dietary and lifestyle modifications

Since Meniere’s disease cannot be treated with medications, what treatment may patients benefit from?

surgical destruction of affected labyrinth

If hearing loss cannot be improved with a hearing aid, what procedure may help?

artificial cochlea implantation for sensorineural hearing loss

Cochlear Implant

device that stimulates auditory nerve using electrical impulses, which then carry current to brain

passes damaged portion of the ear, provides increased sound not re-creating normal hearing

What dietary change may patients with Meniere’s disease benefit from?

salt-restricted diet, diuretics, antihistamines all to control labyrinth edema