exam 2 Flashcards
(193 cards)
1
Q
what is a nucleus and what can they do
A
nucleus can: -send projections to more than one place (to one or more other nuclei) -receive projections from more than one place (from one or more other nuclei)
2
Q
auditory cortex
A
-transverse temporal gyrus of Heschl
3
Q
brainstem structures
A
- medial geniculate body
- *thalamus underneath
- inferior colliculus
- *midbrain
- lateral lemniscus
- *pons
- superior olivary complex
- cochlear nucleus
- *medulla
4
Q
middle ear muscles and innervation
A
- tensor tympani
- trigeminal CN V
- stapedius
- facial CN VII
5
Q
specificity and sensitivity of behavioral site of lesion tests is
A
not always high
**absent in todays audiology
6
Q
acoustic immittance
A
- have become routine as pure tone and speech audiometry
- guides the diagnostic audiologist in identifying abnormalities in the auditory system
- procedure is basic to the test battery
**impedance + admittance
7
Q
acoustic impedance
A
- in plane of TM
- variety of impedance meters used today
8
Q
compliance
A
related to dimensions of an enclosed volume of air as expressed on a scale of different units of measurement
9
Q
immittance
A
used as an all-encompassing term to describe measurements made of tympanic membrane impedance, compliance or admittance
10
Q
three measurements made on acoustic immittance meters
A
- static acoustic compliance
- tympanometry
- acoustic reflex
11
Q
static acoustic compliance
A
- static acoustic admittance
- the mobility of the membrane as a function of various amounts of positive and negative air pressure in the external ear canal
12
Q
tympanometry
A
a procedure in acoustic immittance testing which measures the ease which sound flows through the tympanic membrane while air pressure against the membrane is varied
-the purpose is to determine the point of maximum compliance of the eardrum membrane
13
Q
acoustic reflex
A
-contractions of the ME in response to intense sounds which has the effect of stiffening the ME system and decreasing its static acoustic compliance
decreased mobility - decreasing compliance - increasing impedance
14
Q
procedure for SAC
A
- first clear ear canal of all debris
- ear tip pressed with tight seal and positive pressure increased with air pump
- once seal is obtained pressure increased to +200 daPa
- next decrease pressure in external ear canal until TM reaches maximum compliance = when pressure on both sides of membrane are approximately equal and eardrum is most mobile
15
Q
c1
A
first measurement, made with the TM immobilized by positive air pressure and represents compliance of outer ear
16
Q
c2
A
reading taken at maximum compliance which represents SAC of OE and ME combined
17
Q
cx(ME)
A
c2(EAC+ME) - c1(EAC)
*to cancel out compliance
18
Q
normal compliance range
A
0.28 - 2.25cm3
19
Q
maximum compliance for normal ears
A
0 daPa
20
Q
high compliance
A
flexible, extra mobile, interruption in chain of bones, or abnormal elasticity of TM
21
Q
low compliance
A
change in stiffness, mass, resistance of ME, fluid accumulation, immobilized osciles
22
Q
SAC is the
A
- weakest in terms of clinical value
- because of overlap in static compliance between normal and pathologic ME
23
Q
tympanogram
A
a graph showing compliance, impedance, of the ME as a function of air pressure against the TM
24
Q
tympanometry procedure
A
- *purpose is to determine the point and magnitude of greatest compliance of the TM
- obtain air tight seal
- introduce +200 daPa of air pressure into external auditory canal
- take compliance reading
- gradually decrease the air pressure and take successive measurements of compliance as the air pressure is reduced
- decrease air pressure until at least -200 daPa
- plot these readings on a tympanogram
25
type A
- represents normal middle ear function
- pressure peak near 0 daPA and -/+ 100 daPa
- normal static compliance
26
type As
- same peak in normal range
- low compliance represents a stiff middle ear system
- pressure peak much shallower
- stapes immobilization, otosclerosis
27
type Ad
- same peak in normal range
- high compliance
- eardrum in very mobile represents a hypermobile eardrum or middle ear system
- amplitude of curve is very high
- flaccidity of TM or separation of the chain of the ME bones
28
type B
- ME pressure not normal
- no visible peak
- no point of maximum compliance
- very stiff middle ear system
- fluid in ME
- earwax or debris occlude ear canal or probe
- tiny hole in TM
29
type C
- pressure in the ME falls below normal
- TM becomes most compliant when the pressure in the ear canal is negative thus equaling ME pressure
- when maximum compliance occurs it is beyond -100 daPa
- problem in ET
30
tympanograms of people with normal hearing loss might be identical to people with
sensory/neural hearing loss
31
acoustic reflex
contraction of one or both of the intra-aural middle ear muscles in response to a loud sound creating an increase in stiffness of the ME system (change in compliance)
32
intra-aural muscle reflex
most normal hearing individuals demonstrate this bilaterally when pure tones are introduced to either ear at 85 or 100 dB SPL
33
acoustic reflex threshold
the lowest intensity at which a stimulus can produce acoustic reflex
34
reflex activating stimulus
RAS
- signal used to produce acoustic reflex
- any kind of sound from a pure tone to a noise band
- 500 - 4000 Hz
- 70-100 dB SPL
* no higher than 115 dB SPL
35
within normal limits
70 - 100 dB HL/SL
36
cochlear loss
20-60 dB SL
| -reduced SL
37
pseudohypacusis
- faker, no hearing loss
| - below 10 dB SPL
38
absent reflex
indicitive of a conductive component, severe to profound sensorineural involvement, or absence of stapedius muscle
39
elevated reflex
| >100 dB HL
possible minimal conductive componant or sensorineural involvement
-possible sign of VIII nerve lesion
40
characteristics of acoustic reflex
- individual variability in amplitude of acoustic reflexes
- tend to last for duration of stimulus
- latency period between presentation of the stimulus and reaction of muscles
- 3-10 msec for high
- 100 msec for low
- on and off responses observed
- acoustic reflexes show relatively little adaptation
- as stimulus intensity increases, the amplitude of the acoustic reflex increases up to a maximum contraction at 15-20 dB above ART
41
R -normal hearing
| L - normal hearing
contralateral - present at normal SL
| ipsilateral - present at normal SL
42
R - normal hearing
| L - conductive HL
R contralateral - absent
L ipsilateral - absent
L contralateral - absent or present at high SL
R ipsilateral - present at normal SL
43
R - conductive HL
| L - conductive HL
contralateral - absent
| ipsilateral - absent
44
R ipsilateral
| L contralateral
phone left
| probe right
45
R contralateral
| L ipsilateral
phone right
| probe left
46
R - normal hearing
| L - cochlear HL (mild to moderate)
R contralateral - present at normal SL
L ipsilateral - present at low SL
R ipsilateral - present at normal SL
L contralateral - present at low SL
47
R - cochlear HL (mild to moderate)
| L - cochlear HL (mild to moderate)
contralateral - present at low SL
| ipsilateral - present at low SL
48
R - cochlear HL (severe)
| L - cochlear HL (severe)
contralateral - absent
| ipsilateral - absent
49
R - VIII (AN) HL (mild to moderate)
| L - normal hearing
R contralateral - absent or present at high SL
L ipsilateral - present at normal SL
R ipsilateral - absent or present at high HL
L contralateral - present at normal SL
50
R - normal hearing
L - normal hearing
(brain stem lesion)
R contralateral - present at normal SL
L Ipsilateral present at normal SL
R ipsilateral - present at normal SL
L contralateral - absent
51
R - normal hearing
(cortical lesion)
L - normal hearing
R contralateral - absent
L ipsilateral - present at normal SL
R ipsilateral - present at normal SL
L contralateral - absent
52
if there is a disorder/lesion about acoustic reflex arc
reflex will appear normal
53
R normal hearing
(VII nerve pathology)
L normal hearing
R contralateral - present at normal SL
L ipsilateral - present at normal SL
R ipsilateral - absent
L contralateral - absent
54
acoustic reflex decay
with constant tone, stapedius muscle will gradually relax following contraction to a loud sound
55
loudness growth
normal steady rise of loudness vs. intensity
56
loudness recruitment
-very rapid and quicker than normal loudness growth
57
loudness decruitment
slower than normal increase in the loudness of a signal as intensity is increased
58
ABLB test
alternate binaural loudness balance
- best way to test for loudness recruitment in patiesnt with unilateral hearing loss
- compare increase in loudness in normal ear to increase in loudness in abnormal ear
* *rarely used today
59
patients with lesions in cochlea
are able to detect extrememly small changes in intensity
60
SISI
short increment sensitivity index
- test ability of patient to detect the presence of a 1 dB increment superimposed on a continuous tone presented at 20 dB SL
* patients with cochlear lesions can detect and get scores close to 100
* *patients with retrocochlear and conductive hearing loss as well as normal hearing get scores close to 0
rarely performed
61
tone decay
- tones that are sustained above a threshold fade rapidly to inaudibilty in those with cochlear lesion
- no tone decay in normal and conductive hearing loss
- lesions in auditory nerve show dramatic tone decay at all frequencies
62
AEPs
electrical potentials or activity caused by a signal
63
electrodes
electrical activity evoked by sound is picked up by electrodes
64
non-inverting (active) electrode
p/u signal + noise
65
inverting (reference) electrode
ideally p/u noise only
66
latency
-time period that elapses between the introduction of a stimulus and the occurrence of the response
67
amplitude
the strength, or magnitude of the AEP
68
EcochG
electrocochleography
- procedure for measuring electrical responses from the cochlea of the inner ear
- primary use is diagnosis and monitering of conditions of inner ear
- 2-3 milliseconds
69
AMLR
AEP occurring from 10-100 milliseconds in latency
- originates in the cortex
- low frequencies
70
LER/ALR
- auditory late responses, cortical auditory evoked potentials
- occur between >100 milliseconds and presumably arise in cortex
- stimulus can be speech or tones
- identify upper brain lesions
71
P300/EPR
auditory event related potentials
- 300 miliseconds
- involve association areas of the brain
72
SOAEs
spontaneous otoacoustic emissions
- produced without any acoustic stimulation
- not all people have SOAEs
73
evoked OAEs
- produced following some acoustic stimulation
- most people with normally functioning cochleas have evoked OAEs
- 3 ways to measure
74
TEOAEs
transiently evoked OAEs
-stimulus: brief click
normal response: broadband emission
-signal emenate from cochlea 5-20 msec after sound received
75
DPOAEs
- used in clinic
- stimulus: brief simultaneous presentation of 2 pure-tones
- normal response: emission at the frequency of the distortion product of the presented tones
76
pinna
```
auricle
-helix
-antihelix
-concha
-tragus
lobule
```
77
osseo cartilaginous junction
-pinna
-auditory canal
-tympanic membrane
-2/3 cartilage
where cartilage meets bone is junction
78
tympanic membrane
- pars flaccida
- pars tensa
- umbo
- cone of light
* healthy
- pearly white
- semi-transparent
- cone of light
- cone shaped
79
microtia
- ears of very small size
- with normal canal, unlikely to be associated with hearing loss
- twice as frequent in males as in females
80
anotia
- no ear
| - rare congenital deformity characterized by total absense of pinna
81
atresia
- entirety of external auditory ear canal never formed
- congenital abnormality
- may occur in one or both ears
- may occur alone or with other issues
* *often associated with microtia
82
macrotia
-outstanding pinna
83
stenosis
- collapsed canal
- narrowing of a EAM
- easily becomes impacted with cerumen
- can lead to conductive loss if lumen clogged
84
external otitis
cysts and tumors
-infection that occurs in the skin of the EAC
"swimmers ear"
-water trapped in ear or fungus
85
myringitis
- inflammations of the TM
| - blood blisters on surface of TM
86
osteoma
- bony or cartilage tumor in the ear canal
- do not cause hearing problem unless growth is larger than lumen of canal and conductive hearing loss results
- may result in serious infection of EAC
87
perforation of TM
- excessive pressure buildup
- response to infection
- direct trauma
- pressure from explosion
- traumatic perforations show better spontaneous closure
- place cigarette paper over to help close
- easy to retear
88
myringoplasty
- surgical repair of a perforated TM
- vein grafts, not skin grafts
* *prefer to use fascia
89
tympanosclerosis
- TM becomes thickened and scarred
- deposits of calcium
- response to infection
- disorders of ME
- sometimes hearing loss
- stiffening effect
- do not respond well to treatment
90
pinnaplasty
reconstruction of pinna
| -repair with rib cartilage grafts
91
negative pressure
retraction of TM
| -colds, allergies, sinus infection
92
barotrauma
-sudden changes in air pressure as in flying, or diving
93
chloesteatoma
- disease in which skin cells/debris collect & grow in ME cavity
- epidermal cyst
- keratin protein mixed with squamous epithelium and fats such as chlosteral
- best treatment is surgery
- otorrhea - foul smelling discharge
- elevated AC levels
- acquired
- ET dysfunction
- recurrent
94
necrosis
- death of the mucosa, submucosa and TM
| - if condition furthers TM may rupture
95
otosclerosis
- common cause of hearing loss
- hereditary in 70% of all cases
- more common in women
- progressive disorder causing conductive hearing loss
- otospongiosis
- immobilizing stapes footplate fixing to oval window
- tinnitus
- ear discomfort
- bone conduction loss
96
schwartze sign
-rosy glow seen through TM
97
paracusis willisii
speech is easier to understand in presence of background noise
98
disarticulation of the ossicles
- common cause is trauma
- subluxation - partial dislocation
- conductive hearing loss
- mild
99
tympanoplasty
- surgical reconstruction of ME
- myringoplasty
- attach ossicles together
- improvement varies
- dependent on ET
100
Pressure equalizing tube
- inserted through incision in TM to normalize ME pressure
- remain for several weeks to several months
- used with fluid pressure
- new tubes can stay in place permanently
- successful
101
myringotomy
-incision in TM to suction and remove fluid and relieve fluid pressure
102
stapedectomy
- success rate - 90-95%
| - removal of the stapes
103
impedance componants
- frictional resistance
- reactance - mass & stiffness
- frequency
104
equivalent ear canal volume
estimate of volume of air between probe tip & TM
105
PB max and PBmin
phonetically balanced
106
retrocochlear hearing loss
decline in word recognition as levels get louder
107
normal rollover ratio
0.0 - 0.44
108
retrocochlear
0.45-1.0
109
rollover ratio
PBmax-PBmin/PBmax
110
purpose of behavior site of lesion
locate the lesion
111
anterior ligament
attached to head of malleus
112
posterior ligament
short process of incus
113
exotoses
many bony growths need to be removed
114
I
distal portion of AN
115
II
proximal portion of AN
116
III
CN
117
IV
SOC
118
V
lateral lemiscus
119
ABR threshold
lowest intensity for ABR V to show
120
lesion in retrocochlear
no waves
prolonged wave V
or long interpeak latencies
121
VII nerve tumor
peaks after wave I absent or delayed
122
stacked ABR
- uses amplitudes
- neural response strength
- easier to identify tumors
- uses high pass
- division of ABR into 5 frequency bands
123
ASSR
auditory steady state resposnse
- no neural generator
- stimulus AM/FM
- focus on frequency and latency
- children
- stimuli that are most frequency specific may be used to obtain thresholds
124
intraoperative monitering
-when under surgery do AEP
125
inner hair cells
3500
- pear shaped
- dont move
- limited stimulation w/out outer hair cells
- 1:1 innervation
- u shaped formation
126
outer hair cells
12000
- long and skinny
- sharpening wave
- enhance reception of sound
- 1:10 innervation
- v shaped
127
possible failure
-vernix can block canal
128
limitations
- conductive hearing loss
| - interpreted with caution
129
normal hearing
-10 - 15 dB
130
slight hearing loss
16-25 dB
| -possibly hearing aid in children
131
mild hearing loss
26-40
| -possible aid in adults, definite in children
132
moderate hearing loss
41-55 dB
| -hearing aid
133
moderately severe
57 - 70 dB
| -hearing aid
134
severe hearing loss
71-90 dB
| -hearing aid
135
profound hearing loss
>91 dB
| -cochlear implant
136
impedance
the opposition to sound wave transmission
- more dense object opposing greater impedance
- as mass and frequency increase, stiffness decreases
137
immittance instrumentation
- earphone
- computer
- probe - loudspeaker, air pump, microphone
138
purpose of immitance tests
tell if ME is functioning properly, and if not show how
139
AEP basic equipment
- elctrodes
- electrode box
- stimulus generator
- amplifiers
- signal averaging computer
- filters
- oscilloscope
- plotter
- disk storage
140
electrode impedance
- low balanced impedance
| - below 5K ohms
141
band pass filter settings
-30 or 100 Hz - 3000 Hz
142
normal response occurs
5-6 msecs after stimulus
143
stimulus
-brief click
144
AEP measures reveal
- lesions, tumors, or impairment in AN or brainstem
| - measures neuroelectric events that occur once and after sound hits cochlea
145
signal averaging
because AEPs are embedded in EEGs
146
signal vs noise
signal - stimulus response
| noise - unwanted electrical activity
147
ABR abnormal if
- interpeak intervals prolonged
- wave latency is significantly different between ears
- amplitude ratios are abnormal
- wave V is abnormally prolonged or disappers
148
latency vs intensity
as intensity increases latency decreases
149
clinical applications of ABR
- newborn auditory screenings
- estimation of auditory sensitivity in young or difficult to test patients
- diagnosis of AN or brainstem dysfunction
- intraoperative monitering
- ICU
150
clinical limitations of ABR
- click only estimates 1000-4000 Hz
| - ABR is not test of hearing
151
ABR parameters influenced by
- age
- gender
- body temp
152
who discovered OAE
-kemp
153
DP
2F1 - f2
154
DP gram
x - frequency
y - sound level dB SPL
-shows cochlear function
155
function of ME
- carries sound from OE to IE
| - match impedance of air in external auditory canal to impedance of fluid in the inner ear
156
chorda tympani
- branch of facial nerve in ME
- often in way in surgery
- carries taste sensation
- when cut taste changes recovers after several months
157
parts of ME
- malleus
- incus
- stapes
- oval window
- promontory
- round window
158
joints of ossicles
malleoinductal
| inductostapedial
159
eustachian tube
connects ME to back of throat
opens in nasopharynx
-malfunction can lead to negative pressure in ME and infection
160
impedance mismatch
- larger TM to 17 times smaller oval sindow
- able to put 23 times more pressure on than sound alone would do
- value is 30 dB
- almost exactly 28 dB loss of air to fluid impedance mismatch
161
eustachian tube in adults and children
- children horizontal and shorter
| - adults down at 45 degrees and longer
162
otalgia
pain in ear
162
otalgia
pain in ear
163
otorrhea
dischare
163
otorrhea
dischare
164
superior olivary complex
located on pons
| -receives input from cochlear nuclei
164
superior olivary complex
located on pons
| -receives input from cochlear nuclei
165
cochlear nuclei
- on pons
- lowest
- AN fibers terminate on cochlear nuclei
165
cochlear nuclei
- on pons
- lowest
- AN fibers terminate on cochlear nuclei
166
medulla
- cochlear nuclei
- SOC
- lateral lemniscus
166
medulla
- cochlear nuclei
- SOC
- lateral lemniscus
167
lateral lemniscus
- major pathway for transmission of impulses of ipsilateral lower brainstem
- from SOC to inferior colliculus
167
lateral lemniscus
- major pathway for transmission of impulses of ipsilateral lower brainstem
- from SOC to inferior colliculus
168
inferior colliculus
- midbrain
- receives stimulation from both SOC
- neurons connect to medial geniculate body
168
inferior colliculus
- midbrain
- receives stimulation from both SOC
- neurons connect to medial geniculate body
169
medial geniculate body
-thalamus
169
medial geniculate body
-thalamus
170
otalgia
pain in ear
171
otorrhea
dischare
172
superior olivary complex
located on pons
| -receives input from cochlear nuclei
173
cochlear nuclei
- on pons
- lowest
- AN fibers terminate on cochlear nuclei
174
medulla
- cochlear nuclei
- SOC
- lateral lemniscus
175
lateral lemniscus
- major pathway for transmission of impulses of ipsilateral lower brainstem
- from SOC to inferior colliculus
176
inferior colliculus
- midbrain
- receives stimulation from both SOC
- neurons connect to medial geniculate body
177
medial geniculate body
-thalamus
178
otalgia
pain in ear
179
otorrhea
dischare
180
superior olivary complex
located on pons
| -receives input from cochlear nuclei
181
cochlear nuclei
- on pons
- lowest
- AN fibers terminate on cochlear nuclei
182
medulla
- cochlear nuclei
- SOC
- lateral lemniscus
183
lateral lemniscus
- major pathway for transmission of impulses of ipsilateral lower brainstem
- from SOC to inferior colliculus
184
inferior colliculus
- midbrain
- receives stimulation from both SOC
- neurons connect to medial geniculate body
185
medial geniculate body
-thalamus
