Module: heent assessment of the head and neck

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Upon completion of this module, the student will be able to:

1. Identify the normal anatomical structures involved in the HEENT examination.

2. Perform a complete HEENT examination, noting variations due to age.

3. Name cranial nerves II, III, IV and VI and explain their function.

4. Diagram the visual pathway.

5. Perform an examination of vision, including visual fields, distance vision, near vision, and color vision.

6. Perform a fundoscopic examination and identify the following structures: optic disc, optic cup, background, vessels, and macula.

7. Describe the findings of the otoscopic examination of the tympanic membrane including landmarks, light reflex, general color and pneumatic assessment.

8. Assess hearing including age-appropriate screening methods.
Read applicable sections of the course textbook
Equipment Needed for HEENT Exam:
Pto-ophthalmoscope, ear pieces/nasal speculum

Tongue blade


Snellen chart, eye cover

Pocket visual acuity screen with a 14 inch measure

Tuning fork 256 or 512

Disposable gloves

Glass of water

2” x 2” gauze

  • Amblyopia

  • anisocoria

  • A/V nicking

  • Blepharitis

  • Chalazion

  • Entropion/ectropion

  • Gingivitis

  • Koplik’s spots

  • Leukoplakia

  • Papilledema

  • Pterygium

  • Ptosis

  • Strabismus (esotropia/exotropia)

  • Tophus

  • Torus palatinous

  • Exophthalmos

  • Hordeoleum

  • Arcus senilus

  • Hyphema

1. What are the key symptoms of HEENT disorders?

2. Name and locate/diagram all head and neck lymph nodes.

3. Name and locate/diagram parts of the tympanic membrane.

4. Describe the normal findings of the fundoscopic exam: optic disc, cup, vessels, macula.

5. Describe common normal and abnormal variations in the fundoscopic exam.

6. Describe the clinical significance of a positive Weber or Rinne test.

7. Describe papilledema. What is its clinical significance?

8. What are the clinical features of the eye grounds that might be found in hypertension? Glaucoma? Diabetes mellitus?

9. What are the risk factors for oral cancer?

10. Describe the visual field changes that would be consistent with a lesion:

a. at the optic chiasm

b. at optic nerve

c. retina

d. at optic tract

11. Which of the nasal turbinates are you able to visualize with a nasal speculum?

12. What is the difference between a pterygium and pinguecula?

13. Describe the oral lesions associated with HIV infections.

Which questions are HPI, PMH, SH, FH, or ROS?


I. History

A. If head or neck trauma, gather CC and current status info. Postpone rest of history until x-rays obtained.

B. Head trauma, skull surgery, jaw/facial fractures?

C. Headaches?

1. Does relaxation, exercise, or massage reduce/relieve headaches?

2. Associated with lack of sleep, missed meals, or stress?

D. Any neck injury or surgery?

II. Inspection

A. Skull

1. Size and shape

a. Cranium (forehead--abnormal size/shape?)

b. Congenital abnormalities—(Down’s Syndrome?)

c. Increased bone structure

d. Swellings or injury

e. Swelling of face, jaws, mastoid process?

f. General size and contour of skull (looking down from above)

g. Deformities, lumps, tenderness

2. Face

a. Facial expression

b. Symmetry

c. Involuntary movement

d. Edema

e. Masses or lesions

f. Color and texture of skin

g. Rash

2. Hair & scalp—quality, texture, thickness, and distribution of hair (pattern of loss, if any), swelling, hair

loss, alopecia, presence of nits, dandruff, lesions

3. Skin--lesions, color

III. Palpation

A. Sinus infections/tenderness?

B. Temporal artery

C. Check for TMJ
Health Promotion Questions

  • Job: sitting at computer terminal? risk of head injury? (hard hat?)

  • Use sunscreen?

  • Use seat belts? Use helmets?

What are the regions of the skull?

I. History

A. Eye surgery, trauma, discomfort or vision loss

B. Long standing impairment in acuity or visual changes may not be identified unless you ask

C. Ask about--diplopia, glasses, contacts (when last changed lenses), visions, blurring, photophobia, inflammation,

scotoma, spots, floaters, halos around lights

D. Frequent eye infections/inflammation, sties

E. Clarify meaning of double vision, blurred vision or pan vision.

F. Identify the circumstances, background and characteristics of complaint.

G. Determine effects upon daily activities.

H. Clarify unilateral or bilateral; persistent or intermittent associated disease? DM, HTN, HIV

I. Any medications for eyes


K. FH (cataracts, glaucoma, blindness)

II. Visual acuity (CN II Optic Nerve)

A. Pocket screener or Snellen chart (20’), check also for near vision

B. Indicate if tested with glasses (corrected) or not

III. Inspection

A. External Eye Exam (SIMPLE) Symmetry, Inflammation, Masses, Puncta, Lacrimal Duct, Eyelids

1. Abnormals for external exam

a. Lid lag

b. Lid ophthalmus (incomplete closure)

c. Ptosis (drooping)

d. Blepharospasm

e. Xanthelasma

f. Ectropion (rolling out)

g. Entropion (rolling in)

h. Infections

i. Hordeolum (sty)

ii. Chalazion – nodule away from lid margin

iii. Blepharitis

i. Edema

j. Exophthalmos

k. Ecchymosis

B. Position of corneal light reflex (Hirschberg’s sign) --2-4” using light to see if equally centered on pupils

1. Esotropia--inward deviation

2. Exotropia--outward deviation

C. Conjunctiva--sclera, iris

1. Use penlight to view surface

2. Check pigmentation, hemorrhage, growths, inflammation, jaundice

3. Examine palpebral and bulbar conjunctiva--appearance, injection, pinguecula

a. Palpebral conjunctiva – lines lid

b. Bulbar conjunctiva – over sclera

c. Conjunctivitis – viral, bacterial, allergic

d. Pterygium – thickening of bulbar conjunctiva

D. Cornea (CN V)

1. Should be clear, smooth

2. Arcus senilis

3. Corneal reflex

a. CN V – Trigeminal

b. CN VII - Facial

4. Angle penlight from side to check clouding, ulceration, opacities

5. Corneal abrasions--cause severe pain each time lid moves over cornea

6. Pupils and pupillary reaction to light (CN II, III)

a. Check size (normal is 3-5 mm), shape, equality

b. Patient looks at examiner, penlight brought from side to center line of vision

c. Direct and consensual (other eye constricts) pupillary reaction

d. Check equality, shape, size (3-5 mm normal), brisk or sluggish

i. Accommodation-constrict

ii. Convergence--breaks at about 2”

iii. When checking convergence accommodation--have pt. gaze into distance, then focus on

penlight as moves toward nose

iv. Anisocoria – unequal pupils

7. Cover test--strabismus--esotropia or exotropia

E. Extra ocular movements (CN III, IV, VI) (“LR6, SO4, the rest are 3, there ain’t no more”)

1. Direct patient to move eyes into six cardinal fields of gaze to test function of each

2. Check if one of the EOM’s is paralyzed

3. Check for any lid lag

4. Ocular muscles abnormals

a. Strabismus – deviation of eye

b. Tropia – misalignment or deviation of eye

c. Exotropia – outward turning

d. Esotropia – inward turning

e. Phoria – mild weakness apparent only with cover test

f. Exophoria – outward drift

g. Esophoria – inward drift

F. Visual fields--confrontation testing

1. Patient stares steadily at examiner’s eye; examiner slowly brings finger from lateral position into field of

vision, noting when client first sees examiner’s finger. (test 8 visual fields)

2. Normal: vertical 45°, temporal 85°-90°, nasal 60°, superior 60°, inferior 70°

3. When checking temporal fields--come from behind the patient

G. Tonometry--measures intraocular pressure

H. Ophthalmoscopy

1. Best performed with dilated pupils (10% neosynephrine HCL ophthalmic viscous solution)

2. Patient stares at fixed distant object: move in at 15 degree angle from line of vision--start at 12” and

check red reflex--right eye to right eye and left eye to left eye

3. 8-10” positive + diopter lens used; as approach eye, gradually reduce power to visualize abnormalities

in the cornea, aqueous, lens, vitreous until retina comes into focus, reduce that lens necessary to focus

on the retina--negative diopter = red

4. Retina--examine optic disc and cup, major branches of optic vessels, arteries & veins, macula check

clarity of disc edges, color, crescents, size of cup

5. Normal findings

a. C:D ratio: cup usually less than half the diameter of disc

b. A:V ratio, artery to vein ratio is normally 2-3 or 4-5

c. Color of the background varies with the patient’s skin color

6. Abnormals

a. Disc: pallor, increased cupping (glaucoma), papilledema (increased intracranial pressure) vessels:

venous engorgement, hemorrhages, arteriolar narrowing, hypertension, arterial occlusion, copper

or silver wiring, tortuosity, vessel proliferation, sheathing, A-V nicking

b. Retina: exudates, hard, soft (cotton wool, waxy), color changes, retinal detachment

I. When to do a Fundoscopic exam

1. Suspected neuro problems

a. Headache

b. Dizziness

2. Diabetes

3. Hypertension

4. Toxoplasmosis

J. Optic disk

1. Size: 1.5 mm

2. Shape: round > slightly oval

3. Color: salmon pink, yellowish-white

4. Margins: distinct, fuzzy nasally

5. Disc-cup ratio – physiologic cup/optic disk should be <0.5

6. Normal variations

K. Retinal vessels

1. Number: branches to all four quadrants

2. Color: arteries brighter than veins (veins slightly darker and larger than arteries)

3. A-V ratio (diameter) – A/V > ½ (1/2 or less may mean diabetes

4. A-V crossing – should cross with no disruption of blood flow (if flow impaired = A/V nicking)

L. Macula

1. Location – 2 disc diameters temporally from disc

2. Fovea – center of macula

3. NOTE: uncomfortable for patients to have light shined on macula: aim for disc instead

M. Fundus Background

1. Color – bright orange/red; consistent OU

2. Abnormalities

a. Micro aneurysms

b. Hemorrhage

c. Hard exudate: creamy or yellowish, well-defined borders

d. Cotton wood spots (soft exudate): white/gray ovoid lesions with irregular borders

N. Any eye pain

1. Numb eye with Tetracaine

2. Use fluorescein paper (wet with sterile saline or water)

3. Use Wood’s light to check for abrasions, foreign bodies

Eye History: Children
  • Infant: gaze at you or other objects; blink at bright lights or quick movements?

  • Eyes ever crossed? Ever move in different directions?

  • Does child bump into things?

  • Does child sit near television at home?

  • How is child’s progress in school?

Eye History: Older Adult/Elderly

  • Do eyes feel dry?

  • Difficulty seeing in front of you but not to the sides?

  • Problems with glare?

  • Problems discerning colors?

  • Difficulty seeing at night?

Health Promotion Questions

  • Last eye examination?

  • Eye care insurance?

  • Occupation: prolonged reading or use of video display terminal?

  • Any eye problems from air at work/home?

  • Use goggles when appropriate? (when using tools, sports, swimming?)

The “Red Eye” Differential Diagnoses


  • If blurring: intermittent, clears on blinking

  • Discharge: usually, crusting of lashes

  • Pain: none or minor and superficial

  • Pupils: Normal size and response

  • Conjunctival injection: Diffuse

  • IOP: Normal (don’t measure if discharge)

  • Cornea: Clear


  • Vision: slightly blurred

  • No discharge

  • Pain: Moderately severe, aching, photophobia

  • Pupil: constricted, minimal response

  • Conjunctival injection: Circumcorneal

  • IOP: Normal to low

  • Cornea: clear or slightly hazy

Keratitis (Corneal inflammation or foreign body)

  • Vision: slightly blurred

  • Discharge: none to mild

  • Pain: sharp, severe foreign body sensation

  • Pupil: normal or constricted, normal response

  • Conjunctival injection: circumcorneal

  • IOP: Normal (Caution: do not measure)

  • Cornea: Opacification present; altered light reflex; (+) fluorescein staining

Acute Glaucoma (REFER)

  • Vision: marked blurring

  • Discharge: none

  • Pain: very severe, frequently N & V

  • Pupil: dilated, minimal or no reaction

  • Conjunctival injection: diffuse with prominent circumcorneal injection

  • IOP: elevated

  • Cornea: hazy; altered light reflex

  • Anterior chamber depth: shallow


I. History

A. Abnormals common with very young and very old

B. Most adults o.k.

C. Ask, “any ear trouble?”

D. If yes, then more ROS—pain, deafness, discharge, tinnitus, vertigo, cracking, foreign body

E. Questions to ask if “earache”—fever, perforation, trauma, skin diving, flying, past complications,

treatment, history of swimming, drainage, frequent ear infections

F. Any hearing differences in one/both ears?

G. Any problems with ear wax? What is done?

H. Ear injuries, surgeries?

I. Deafness—ear involved, progression, occupation/education

J. Tinnitus—ear involved, progression, drug history, occupation, head injury, recent URI

K. Vertigo, problems with balance —perforation, infections of middle ear, recent URI, head injury, syncope,

transient paralysis

L. Rx or OTC meds or home remedies for ears or any other conditions?

M. Family history of anyone with hearing problems

N. Occupational history

II. Inspection

A. Pinna (auricle)

1. Size and shape

2. Level on head

3. Flat or protruding

4. Tophi or nodules

B. Auricle, meatus, tragus, mastoid area

1. Otoscopic exam—largest speculum that will fit

a. Retract auricle up and back in adults; down and backward in babies

b. Advance slowly; ANCHOR the otoscope

c. In sick child—must examine ear; how to restrain

d. Cerumen—cleaning: curette, irrigation

e. Brace otoscope against head; tilt client’s head toward opposite shoulder, check tympanic


i. For light reflex, landmarks, color and luster, retraction or bulging of membrane, fluid levels or bubbles; canal for erythema or drainage, blood

ii. Oval thin, partially transparent grey

f. Gently move speculum to inspect entire ear drum

g. NOTE: the more scarring on the TM form healed ruptures, the less mobile it become - conductive

hearing loss

C. External auditory canal

1. Cerumen, discharge, foreign bodies, tumors

2. Signs of infection

III. Palpation

A. Auricle, meatus, tragus, mastoid area

B. External ear

1. Tophi and nodules

2. Assess for tenderness (with ear pain, discharge or inflammation)

a. Move auricle

b. Press on tragus

c. Press on mastoid

IV. Hearing --(CN VIII)

A. Conductive loss-most common--involves outer and middle ear; causes: ear wax, perforated TM., fluid—

middle ear, otosclerosis (stapes immobilized)

B. Sensorineural loss-involves either cochlea VIII, cranial nerve, or brain

C. Weber--tuning fork in middle of head, lateralization occurs with conductive and perceptive loss

1. Conductive loss--heard best in ‘bad ear’

2. Sensorineural--heard worse in ‘bad ear’

D. Rinne’ air conduction longer than bone--hold vibrating fork against mastoid process--when no longer heard,

hold it adjacent to external meatus of ear--test for conductive loss and middle ear problems.

E. Audiometry--watch ticking or whisper

V. Ear assessment – concepts

A. Lightheadedness – detachment

B. Vertigo – surroundings swirling around

C. Dizziness – disturbance in relationship to space (person feels as if they are spinning)

VI. Hearing Loss

A. Otosclerosis: bones fuse; ages 40-50 have some degree of hearing loss

B. Conductive hearing loss: sound not getting to hearing apparatus

C. Sensory hearing loss: high pitched sounds are the first to NOT be heard

D. Mixed hearing loss

E. Vestibular Testing

1. Romberg’s sign

2. Past-pointing

3. Nystagmus

Ear History: Children

  • Infant: respond to loud or unusual noises?

  • If > 6 months, does infant babble?

  • If > 15 months, does toddler rely on gestures and make no attempt at sound?

  • Child tugging at either ear?

  • Any coordination problems?

  • Hx: meningitis, recurrent OM, mumps, encephalitis?

Ear History: Older Adult/Elderly

  • Any recent change in hearing?

  • Wear a hearing aid?

  • If so, for how long?

  • How do you care for it?

  • Hearing loss? Do you wear a hearing aid?

Health Promotion Questions

  • Last ear exam/hearing test?

  • Results of test?

  • Any meds for ears?

  • Any concerns about ears/hearing?

  • Do you work around loud equipment or machinery? (or LOUD MUSIC!)

What are the 3 bones of the middle ear?
Case study discussion

  1. 15-year-old boy with “earache”

    1. What questions would you ask for HPI?

    2. What physical exam would you perform?

c. What physical findings would help you diagnose the complaint?

I. History

A. Dryness, bleeding, drainage, allergies causing breathing difficulties, broken nose, sneezing, drug use, sense

of smell

B. Nasal discharge or post-nasal drip

II. Inspection

A. Deformity, asymmetry, inflammation

B. Test for patency of each nostril

C. Insert nasal speculum into each nostril--anteroposterior direction--avoid pressure on septum

1. First inspect lower portion of nose--mucosa for color, swelling, drainage, bleeding, septal deviation,

bleeding, perforation

2. Then tip head back and view inferior and middle turbinates for color, edema, drainage, polyps.


I. History

A. Infection, congestion, headaches, drainage, tenderness, allergies causing breathing difficulty?

II. Inspection

A. Swelling, color

III. Palpation

A. Press or percuss: compare bilaterally

B. Frontal, maxillary are able to be assessed; ethmoid & sphenoid are not

IV. Transilluminate

I. History

A. Ability to chew, teeth, gums, dental care, tonsils, sore throat, sores, lesions/ulcers, cold sores, swallowing,

chewing, condition of lips, tongue, any changes in sound of voice?, snorking and/or stop breathing in sleep?

II. Inspection

A. Using gauze, glove, tongue blade, light

1. Lips--color, moisture, ulcers, lesions, cracking

2. Buccal mucosa - color, pigmentation, ulcers, nodules

a. Ducts of salivary glands

3. Gums and teeth

a. Discoloration, inflammation, swelling, bleeding, retraction of gums

b. Position, shape, number of teeth loose/missing, discoloration, caries

4. Hard palate

a. Shape, torus palatinous, color

5. Tongue

a. Color, texture, papillae

b. Use gauze and inspect sides of tongue, under surface

c. Floor of mouth, submaxillary ducts, frenulum, signs of carcinoma

d. Ask patient to put out tongue--check for symmetry, fasciculation--12th cranial nerve


e. Press tongue blade on the middle of arched tongue and ask patient to say “ah” watch for the rise

of the soft palate (testing for the 10th C.N.)

f. Inspect soft palate, anterior and posterior pillars, uvula, tonsils, post. pharynx

g. Tonsils--color, size, symmetry, exudate, edema, ulceration, crypts

h. Frenulum

III. Palpation

A. Any suspicious or tender areas

IV. Differential Diagnoses for sore throat



Additional Questions: Children

  • Drinking water treated with fluoride?

  • Use pacifier or thumb?

  • When did teething begin?

  • Tonsils present? If not, when removed?

Additional Questions: Older Adult & Elderly

  • Do you wear dentures? If so, how well do they fit?

Health Promotion Questions
  • Do you grind your teeth? Last dental exam? Floss?

  • Tobacco use? (Smoke a pipe? Chew tobacco or use snuff?)

Describe a crowded airway.

Describe Grade 3 tonsils.
Case study discussion

7-year-old girl with “sore throat”

a. What questions would you ask for HPI?

b. What physical exam would you perform?

c. What are the top 3 differential diagnoses you would consider?

I. History

A. Pain, swelling, nodes, dysphagia, thyroid trouble, any neck injury or surgery

II. Inspection

A. Symmetry, masses, scars, parotid glands, lymph nodes, thyroid swelling, pulsations, ROM, abnormal

pulsations, vein distension, enlargement of thyroid, lymph, salivary glands, deviation of trachea, neck


III. Auscultation

A. Check for bruits

1. Carotid arteries

2. Temporal arteries

3. Thyroid if enlarged

IV. Palpation

A. Lymph nodes--palpate preauricular, postauricular, occipital, tonsillar, submaxillary, submental, superficial

cervical, post. cervical, deep cervical, supraclavicular

1. Note exact location, size, shape, consistency, mobility (freely movable, adherent or matted together),

tenderness, texture (hard, soft, firm)

2. In enlarged, tender nodes--examine areas they drain

B. When to biopsy lymph nodes?

1. Immediate biopsy is indicated for painless, rubbery node of recent onset, especially if >1-2 cm in diameter

2. A smaller, rapidly enlarging node is also a biopsy candidate

3. Unilateral nodes should have a biopsy sooner than bilateral ones

4. More conservative with stable node
What are the 10 groups of lymph nodes?

I. Inspection-

A. Identify tracheal cartilages--thyroid, cricoid

B. Tracheal deviation

II. Palpation

A. For tracheal deviation--finger along each side of trachea

1. Should be equal spaces between each side and sternocleidomastoid muscles

I. Inspection

A. Visibility, contour, symmetry

II. Palpation

A. From behind or in front

1. Neck slightly extended, fingers in nape of neck

2. Identify cricoid cartilage and then feel the thyroid isthmus below it

3. Ask pt. to swallow--feel isthmus and lateral lobes as pt. swallows pt. can sip a glass of water

B. Ask pt. to bend neck forward and to the right; move thyroid cartilage to the right with your left hand, palpate

with right hand while asking pt. to swallow--repeat on other side by reversing technique


I. GENERAL APPEARANCE: Stature and weight

  1. The elderly experience a change in body stature as a result of MSK and subcutaneous tissue changes.

  2. The spinal column shortens as discs thin and compress and there are associated postural changes resulting in a flexed stance.

  3. Subcutaneous fat deposits decrease in the periphery and are redistributed to the trunk, especially the hips and abdomen.

1. Subjective complaints

    1. body image changes--clothes fit differently, increase waist size

    2. diminished height

2. Objective findings

    1. long thin extremities

    2. accentuation of bony prominences

    3. increased abdominal girth

    4. knee and hip flexion

    5. kyphosis of spine

    6. muscle atrophy of arms and legs

    7. diminished spontaneous movement


  1. There is generalized loss of subcutaneous tissue and sebaceous, sweat glands and hair follicles.

  2. Collagen and elastin degenerate, blood vessels thicken and superficial vessels become prominent.

  3. Loss of estrogen in women leads to the development of some male characteristics.

  4. There is extrapyramidal tract impairment which affects facial reaction as well as producing slowing of movements.

1. Subjective complaints

    1. loss and thinning of hair

    2. wrinkling of face and neck

c. chin whiskers (female)

d. decreased facial hair (male)

2. Objective findings

    1. graying thin hair

    2. wrinkled dry facial skin

    3. facial hair growth (females)

    4. prominent superficial face blood vessels

    5. thinned and bristling eyebrows

    6. impassive facial expression with decreased eye blinking


  1. Skin becomes thickened in nasal area, and gravitational pull makes organs appear longer.

  2. CNS changes contribute to decreased smell (parietal lobe).

  3. There is thinning and drying of nasal mucous membrane.

1. Subjective complaints

  1. nose is larger

  2. loss of smell

  3. epistaxis

  1. Objective findings

  1. large elongated ‘thick skinned’ vascular nose

  2. inability to recognize scents or discriminate between smells

  3. shiny, vascular nasal membrane turbinates


  1. There are atrophic changes which occur in the mouth. Salivary glands and lateral papilla on sides of the tongue atrophy and mucous membranes thin.

  2. Facial muscles become lax, and mandible loses normal contours due to bony changes, gravitational pull and muscle weakening.

  3. There is inward bulging of the buccal mucosa because of loss of elasticity of the fibers that attach the buccinator muscle and the mucous membrane.

  4. Gingival tissue atrophy and recede, and there is a diminished cough and swallowing reflex.

  5. Neuronal degeneration results in a diminished sense of taste, especially sweets.

  6. The surface pattern of and color of teeth change, roots are resorbed and pulp fibroses and calcifies.

  7. Dentine loses permeability and becomes dehydrated.

  8. Loss of skin elasticity and gravitational pull result in accentuated wrinkling in the neck area, and the musculoskeletal changes of the spine produce a forward tilting of the head.

  9. The neck is shortened as a result of these changes and the thyroid may descend below the clavicles.

  10. Elongation of the aorta and elevation of the aortic arch may cause malposition or distention of the innominate artery or jugular vein.

  11. Tonsillar lymph nodes may be calcified as a result of old infections such as tuberculosis.

  12. There is a loss of elasticity in laryngeal muscles and cartilage.

  1. Consider hearing loss in three ways (all 3 benefit from hearing aid):

      1. degree--volume above normal level needed to hear

      2. configuration--rage of frequencies at which loss occurs

      3. type--part of the auditory system affected.

B. Type influences treatment

  1. conductive--basically mechanical; often treated surgically or manually

  2. sensorineural--abnormality of cochlea, auditory nerve or brain

    1. infections--in utero or infancy/childhood

    2. drugs (antibiotics)

    3. congenital (Down’s syndrome, cystic fibrosis, etc.

    4. tumors

    5. presbycusis

3. Mixed--combination of 1 & 2

4. Central--centers responsible for decoding nerve signals that represent could can be damaged by trauma, strokes, tumors, and genetic defects. Peripheral hearing is good but patient cannot process the information.

C. How Does A Hearing Aid Help?
1. By setting or programming the amount of amplification the instrument provides at various frequencies,

the hearing aid attempts to make speech easier to hear and understand.

2. Although the aid amplifies sound it does not automatically improve the clarity of speech for all wearers.
3. Recent improvements in hearing aids:

a. filter background noise

b. change tonal qualities

c. modify (suppress) amount of power delivered to ear to control environmental loudness

d. miniaturization

e. digital--able to program to various listening situations

f. improved signal to noise ratio

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