Anatomy Of Hearing

Front 1

Sound is converted to ______ or vibrational energy in the middle ear.

Back 1

mechanical energy

Front 2

The _______ chain is a series of three small bones: the malleus, incus, and stapes.

Back 2

ossicular

Front 3

The _______ tube connects the middle ear space to the nasopharynx.

Back 3

eustachian

Front 4

If the pressure in the middle ear space (on the medial side of the ear drum) is not equal to the pressure in the ear canal (on the lateral side of the ear drum), the ear drum will displace toward the region of (greater/lesser) pressure.

Back 4

lesser

Front 5

The middle ear space is encased within the _______ bone of the skull.

Back 5

temporal

Front 6

What are the two main areas the make up the middle ear cavity?

Back 6

1.tympanic cavity proper
2.attic/epitympanum/epitympanic recess

Front 7

What is largely considered to be the lateral boundary of the middle ear space?

Back 7

The tympanic membrane

Front 8

Formed by a thin plate of bone known as tegmen tympani

Back 8

superior boundary

Front 9

Formed by the tympanic plate of the temporal bone

Back 9

Inferior boundary

Front 10

A thin plate of bone that is perforated in the superior region by an opening for the ET and an orifice for the tendon of the tensor tympni muscle

Back 10

Anterior/Carotid wall

Front 11

Has a number of landmarks including the tympani aditus, fossa incudis, and pyramidal eminence

Back 11

Posterior/Mastoid wall

Front 12

Formed by a dense portion of the temporal bone which houses the inner ear

Back 12

Medial wall

Front 13

Seperates the middle ear space from the cranium

Back 13

Tegmen tympani

Front 14

An area of indirect communication between the middle ear space and mastoid air cells

Back 14

Tympanic atrium

Front 15

Seperates the middle ear from the jugular fossa

Back 15

Tympanic plate

Front 16

A groove in the temporal bone through which the jugular vein passes

Back 16

Jugular fossa

Front 17

Entrance to the tympanic atrium

Back 17

Tympanic aditus

Front 18

A buldge in the bony foundation of the posterior wall the houses the stapedius muscle

Back 18

Pyramidal eminenece

Front 19

An opening into the basal turn of scala tympani

Back 19

Round window

Front 20

A rounded prominence formed by the lateral projection of the basal turn of the cochlea

Back 20

Promontory

Front 21

A small bowl in the epitympanic recess that accommodates the short process of the incus

Back 21

Round window

Front 22

An area through which the facial nerve courses

Back 22

Prominence of the facial nerve

Front 23

An opening into the vestibule of the inner ear that accommodates one of the middle ear bones, the stapes

Back 23

Oval window

Front 24

The tympanic membrane is a flat membrane.

Back 24

False

Front 25

What are the three layers of the tympanic membrane?

Back 25

Outer, Inner and Middle

Front 26

is formed by an extension of the epidermal lining of the EAM

Back 26

Outer layer of the tympanic membrane

Front 27

Inner layer of the tympanic membrane

Back 27

Continuation of the membranour lining of the MES

Front 28

Middle layer of the tympanic membrane

Back 28

Composed of fibrous material that believed to provide support for the tymapnic membrane

Front 29

Region found in the superior portion of the TM where the fibers are quite sparse

Back 29

Pars flaccida/ Schrapnell's membrane

Front 30

The area of the TM where the fibers tend to be steffer and tensor

Back 30

Pars tensa

Front 31

The groove in the external auditory meatus where the tymapnic annulus is located

Back 31

Tympanic sulcus

Front 32

The fibrocartilaginous ring located along the periphery of the TM

Back 32

Tympanic annulus

Front 33

The opening in the superior aspect of the tympanic annulus

Back 33

Notch of Rivinus

Front 34

The attachment of the malleus to the tympanic membrane

Back 34

Malleal prominence

Front 35

Ligamentous bands that run from both sides of the malleal prominence to the notch of Rivinus forming a triangular area (the location of pars flaccida)

Back 35

Anterior and Posterior malleolar folds

Front 36

The point of the maximal concavity of the tymapnic membrane at the end of the manubrium of the malleus

Back 36

Umbo

Front 37

While performing otoscopy, the ____ _____ _____ is a reflection of the light found on the anterior-inferior quadrant of the tympanic membrane.

Back 37

cone of light

Front 38

When looking at the rught ear, the cone of light will radiate from the tip of the manubrium to the _____ position, whereas it will radiate to the ____ position in the left ear.

Back 38

-5 o'clock - 7 o'clock

Front 39

One of the 3 processes attaches firmly to the tympanic membrane

Back 39

Manubrium of the malleus

Front 40

A large bulb-shaped portion of the ossicle / it protects in an upward direction from the mandibrum into the epitympanic recess

Back 40

Head of the malleus

Front 41

Serves as the point of connection with the second bone in the series, the incus - it is found on the posterior surface of the malleus

Back 41

Articular facet of the malleus

Front 42

A constriction in the bone located between the manubrium and the head

Back 42

Neck of the malleus

Front 43

Spine-like process that can be seen in the region of the juncture of the manubrium and the head

Back 43

Anterior process of the malleus

Front 44

Directed laterally and attaches to the upper portion of the tympanic membrane

Back 44

Lateral process of the malleus

Front 45

The _____ ______ of the incus is directed backward in a roughly horizontal plane intothe epitympanic recess

Back 45

short process

Front 46

The ______ _______ of the incus courses in a vertical direction, roughly parallel to the manubrium of the malleus.

Back 46

long process

Front 47

The medial end of the ________ _________ is covered with cartilage and articulates with the stapes.

Back 47

lenticulas process

Front 48

The smallest bone in the body

Back 48

The stapes

Front 49

Where the stapedius muscle attaches

Back 49

Articular facet

Front 50

Contain a concave articular facet that forms the point connection with the lenticular process of the incus

Back 50

Head

Front 51

The open triangular space between formed by the crura and footplate

Back 51

Obturator foramen

Front 52

The flattened base of the stapes

Back 52

Footplate

Front 53

The shorter, more slender, and less curved crus of the stapes

Back 53

Anterior crus

Front 54

The taller, less slender, and more curved crus of the stapes

Back 54

Posterior crus

Front 55

Attaches the hyaline cartilage to the oval window of the cochlea

Back 55

Annular ligament

Front 56

true or false: The displacement of the stapes in the oval window is more of a rocking/pivoting motion rather than functioning like a piston.

Back 56

true

Front 57

There are six ligaments and two tendons that suspend the ossicular chain within the middle ear. List them.

Back 57

1.Superior malleular ligament
2. Lateral malleular ligament
3. Anterior malleular ligament
4. Annular ligament
5. Posterior incudal ligament
6. Superior incudal ligament
7. Tendon of the tensor tympani muscle
8. Tendon of the stapedus muscle

Front 58

True or False: The Eustachian tube courses at 45 degree angle in adults.

Back 58

True

Front 59

The first third of the Eustachian tube is (cartilaginous/osseous) while remaining two-thirds is (cartilaginous/osseous)

Back 59

osseous; cartilaginous

Front 60

The point where the cartilaginous and bony portion of the Eustachian tube meet is called the:

Back 60

isthmus

Front 61

True or False: At rest the cartilaginous portion of the Eustachian tube is open.

Back 61

False

Front 62

Name the two muscles that control the Eustachian tube.

Back 62

1.Levator veli palatini
2. Tensor veli palatini

Front 63

The tensor tympani is innervated by the ______ nerve (CN V), which when innervated pulls the malleus in an anterior and posterior direction. The stapedius muscle is innervated by the ______ nerve (CN VII) which when contracted will pull the stapes in a posterior direction.

Back 63

-5th cranial (trigeminal)
-facial

Front 64

The Eustachian tube and semicanal of the tensor tympani are seperated by the _____ _____ ________.

Back 64

septum canalis musculotubarii

Front 65

The tensor tympani both have a bony prominence that houses where they enter the middle ear. List these two prominences:

Back 65

a)cochleariform process
b)pyramidal eminence process

Front 66

Inserts at the point where the manubrium meets the neck of the malleus

Back 66

tensor tympani

Front 67

Attaches to the head of the stapes

Back 67

Stapedius muscle

Front 68

True or False: The intrinsic and extrinsic muscles of the pinna are largely nonfunctional in humans.

Back 68

True

Front 69

The internal structure of the pinna has a (cartilaginous/osseous) foundation

Back 69

cartilaginous

Front 70

What three muscles attach to the pinna?

Back 70

1. Anterior auricular muscle
2. Interior auricular muscle
3. Posterior auricular muscle

Front 71

The auricular muscle in humans are _____, serving little function, as opposed to animals that have operational auricular muscles that aid in localization.

Back 71

vestigal

Front 72

Pinnae that are too large

Back 72

Macrotia

Front 73

Pinnae that are too small

Back 73

Microtia

Front 74

Pinnae that protrude at a sharp angle from the head

Back 74

Prominent Ears

Front 75

Pinnae that fold over on themselves

Back 75

Lop ears

Front 76

Pinnae that are missing or incomplete

Back 76

Anotia

Front 77

Damage caused by prolonged exposure to cold temperatures

Back 77

Frostbite

Front 78

Danaging effects from the sun

Back 78

Melanoma

Front 79

True or False: Most medical conditions that affect the pinna have severe audiological consequences.

Back 79

False

Front 80

What is the approximate length (in cm) for the ear canal of the average adult?

Back 80

25 - 30 cm

Front 81

What is the isthmus of the ear canal?

Back 81

The most narrow portion of the ear canal

Front 82

True or False: The opening of the ear canal tends to be more circular in children and oval in adults

Back 82

True

Front 83

How many curve (or bends) are there in the ear canal?

Back 83

2

Front 84

Why do the authors refer to the canal as a "lazy S"?

Back 84

The folds look like an S lying on its side

Front 85

What is meant by the "lumen" of the canal?

Back 85

The outer end of the canal

Front 86

True or False: The ear canal of the infant and child tends to be more horizontal than the adult's.

Back 86

True

Front 87

Why is the diameter of the medial portion of the EAM fixed in adults?

Back 87

Because the foundation of the EAM is bone and the inner 2/3 is osseous.

Front 88

Why do health care professionals pull up and back on the pinna while performing otoscopy?

Back 88

Helps achieve better visualization of the tympanic membrane

Front 89

What three main structures from the bony portion of the canal and what part of the canal do they form?

Back 89

1. Tympanic portion of the temporal bone - forms the floor and anterior wall and the inferior to posterior wall of the canal
2. Squamous portion of the temporal bone - forms roof and a portion of the posterior wall of the canal
3. Condyle of mandible - contributes to the inferior and anterior wall of the canal at the temporal mandibular joint

Front 90

True or False: At birth there is no osseous portion of the ear canal.

Back 90

True

Front 91

An incomplete cartilageous ring that develops from the osseous portion of the EAM.

Back 91

Tympanic annulus

Front 92

By what age, on average does the osseous portion of the EAM reach full maturation?

Back 92

3 years

Front 93

What two types of glands in the EAM contribute to the secretion of cerumen?

Back 93

1. Sebaceous gland
2. Ceruminous gland

Front 94

How is ear wax formed?

Back 94

Sebaceous cells produce oily substance that lubes ear canal then mixes with wax - like substance secreted by ceruminous glands.

Front 95

True or False: Individuals of Asian decent are more likely to have wet, sticky ear wax whereas Caucasians, Latinos, and individuals of Afircan descent are more likely to have the flaky type of cerumen.

Back 95

False

Front 96

Where in the ear canal is cerumen more likely to be found and why?

Back 96

Outer region of EAM - outer layer of skin covering EC migrates out and transports cerumen out of EC.

Front 97

Give two reasons why cerumen can build up, requiring clinical management:

Back 97

1. Lack of epithelial migration
2. Increased production of cerumen

Front 98

Give two examples of the productive function of cerumen:

Back 98

1. Has a slight antibacterial property
2. Has slight anti-fungal property

Front 99

Cerument that covers the tympanic membrane and cerument that blocks the transmission of sound through the EAM

Back 99

Impacted cerumen

Front 100

What type of hearing loss does cerumen impation cause?

Back 100

Conductive hearing loss

Front 101

Which cranial nerves innervate the ear canal?

Back 101

the Vth (trigeminal) - the VIIth (facial) the IXth (glossopharyngeal) the Xth (vagus)

Front 102

Around what frequency does the pinna most effectively collect sound and why?

Back 102

5000 Hz, wavelengths of frequencies in this range are smaller than the pinna

Front 103

The pinna plays a role in localization along both the _______ and _______ planes.

Back 103

horizontal; vertical

Front 104

A tube that is closed at one end and open at the other is a _______ -wave resonator which will reinforce acoustic energy that is _______ times greater than the length of the tube.

Back 104

quarter; 4

Front 105

The frequency range that is typically boosted by the ear canal and the amount of amplification provided.

Back 105

3.5 to 4 kHz by 10-15 dB

Front 106

Why would a patient with an occluding earmold complain that sound is "tinny" or "hollow"?

Back 106

The ressonance patterns of the ear are altered and the natural resonance that occurs at 3000-4000Hz.

Front 107

Are high frequencies or low frequencies more affected by the head shodow effect?

Back 107

High frequency

Front 108

Why would a clinician want to use insert earphones?

Back 108

Pressure from circumaural head phones can cause the canal to collapse

Front 109

The difference in the intensity levels of the signal reaching the two ears is known as the _______ ________ difference.

Back 109

interaural intensity

Front 110

The difference in the time of arrival between the two ears is known as the ______ ______ difference.

Back 110

interaural time

Front 111

The sound pressure arriving at the entrance to the ear canal depends on:

Back 111

the frequency of the sound, the angle of the incidence of the sound, characteristics of the head and torso

Front 112

The combined individual effect show a broad overall increase in acoustic pressure over what frequency range?

Back 112

2000 - 7000Hz

Front 113

The opposition to the flow of energy

Back 113

Impedance

Front 114

Loss of energy caused by fricition

Back 114

Resistance

Front 115

Interacts with frequency in a direct proportional manner

Back 115

Mass reactance

Front 116

Also known as the "elastic reactance factor" and is related to the stiffness of the system or object

Back 116

Stiffness reactance

Front 117

Tend to be preferential to low frequency sounds and offer greater resistance to high frequency sounds

Back 117

Massive objects

Front 118

Preferential to high frequency sounds and offer greater resistance to low frequency sounds

Back 118

Stiff objects

Front 119

A clinical test to assess changes in the stiffness at the TM

Back 119

Tympanometry

Front 120

The air of the middle ear space has an acoustic impedance governed by (mass/stiffness)

Back 120

stiffness

Front 121

The enclosed air in the middle ear space acts as a ________ that limits the flow of (high/low) frequencies through the system.

Back 121

filter; low

Front 122

If a patient with fluid in their middle ear were to have a hearing test performed, would they be more likely to have a high or low frequency hearing loss?

Back 122

Low - frequency HL

Front 123

True or False: The sound that reaches the cochlea is the same as the sound that enters the ear

Back 123

False

Front 124

The hearing sensitivity across the range of audible frequencies is the most sensitive in the (mid to high/low) frequencies and the poorest in the (mid to high/low) frequencies.

Back 124

mid to high; low

Front 125

During an audiometric exam are the thresholds on the audiogram plotted in dB SPL or dB HL.

Back 125

dB HL

Front 126

True or False: The tympanic membrane vibrates in a uniform manner.

Back 126

False

Front 127

Is the impedance of the ossicular chain cominated by stiffness reactance or mass reactance?

Back 127

stiffness reactance

Front 128

At high intensities, the response of the stapes changes from a ________ motion to more of a ________ or ________ motion.

Back 128

piston - like; tilting; rocking

Front 129

What pathology of the middle ear causes the stapes footplate to become fixed over time?

Back 129

otosclerosis

Front 130

What pathology of the middle ear results in increased mobility of the tympanic membrane?

Back 130

ossicular disarticulation

Front 131

What is the significance of the change in response of the stapes at high intensities?

Back 131

Provides protection against damage to cochlear structure/less fluid movement in inner ear

Front 132

What three things happen when the tensor veli palatini and levator veli palatini muscles cause the lumen of the Eustachian tube to open?

Back 132

1. Pressure differential is equalized
2. Fresh air is supplied to the middle ear cavity
3. Small amounts of fluids that could have collected here are drained into the nasopharynx

Front 133

What tyoe of tympanogram are you likely to see when there is negative pressure in the middle ear space?

Back 133

Type C

Front 134

What type of tympanogram are you likely to see when there is fluid in the middle ear space?

Back 134

Type B

Front 135

Why does the middle ear need to function as an "impedance matching device?

Back 135

Air ad the high impedence offered by the fluid in the inner ear

Front 136

What are the three transformer mechanisms of the middle ear?

Back 136

1. areal difference
2. level action
3. buckling effect

Front 137

Which trasformer mechanisms gives the largest contribution to the impedance matching process?

Back 137

area differential

Front 138

Which two ossicles move as a unit to form a level?

Back 138

1. malleus
2. incus

Front 139

By approximately how many decibels does the middle ear tranformer system boost the signal before it reaches the inner ear?

Back 139

33 dB

Front 140

Does the bone conduction oscillator stimulate one or both cochleas?

Back 140

both

Front 141

What are the three mode of bone conduction stimulation?

Back 141

1. Osseotympanic stimulation
2. Inertial simulation
3. Distortional/compressional stimulation

Front 142

Which type of bone conduction stimulation causes the stapes to move in and out of the oval window because of the lag in movement of the ossicular chain?

Back 142

inertial stimulation

Front 143

Which type of bone conduction stimulation causes skull vibrations to radiate into the EAM and thereby stimulate the cochlea in the same manner as air conduction

Back 143

Ossestympanic stimulation

Front 144

Which type of bone conduction stimulation causes movement within the fluidfilled inner ear?

Back 144

distortional / compressional stimulation

Front 145

Inertial stimulation is the dominate vibratory response for (high/low) frequencies whereas compressional stimulation is dominant for (high/low) frequencies.

Back 145

low; high