Final Exam Review Flashcards
(108 cards)
1
Q
What causes tinnitus?
A
- The cause is unknown
- Usually associated with damage to the auditory pathway
- Tinnitus with normal hearing is less common
2
Q
What happens on the neural level with tinnitus?
A
- Change in spontaneous neural activity
- Brain identifies the change and interprets it as sound (tinnitus)
3
Q
How can cochlear damage contribute to perception of tinnitus?
A
- Damage to cochlea leads to increased spontaneous firing rate in auditory structures
- If there is hearing loss, you can get increased firing in the ventral cochlear nucleus, dorsal cochlear nucleus, and inferior colliculus
4
Q
What happens when there’s a decrease in auditory stimulation from the auditory nerve?
A
- Neurons spontaneously start having oscillations
- Spatial synchrony: across space there are a bunch of neurons firing at the same time
- This produces a phantom sound
5
Q
What is the role of the nucleus accumbens?
A
Positive emotions: laughter, reward, reinforcement, learning
Negative emotions: fear, aggression, impulsivity
6
Q
What is the role of the ventromedial prefrontal cortex?
A
Location: frontal lobe at bottom of cerebral hemispheres
- Implicated in processing of risk and fear
7
Q
When should a tinnitus patient be referred to an audiologist?
A
- Symptoms suggest neural origin of tinnitus (tinnitus does not pulse with heartbeat)
- No ear pain drainage, or malodor
- No vestibular symptoms (dizziness/vertigo)
- No unexplained sudden hearing loss or facial palsy
8
Q
When should a tinnitus patient be referred to an ENT?
A
- Symptoms suggest somatic origin of tinnitus
- Ear pain, drainage, or malodor
- Vestibular symptoms (dizziness/vertigo)
- Unilateral tinnitus
- Presentation of symptoms similar to Meniere’s Disease
9
Q
When should a tinnitus patient be referred to emergency care?
A
- Facial palsy
- Physical trauma
- Sudden unexplained hearing loss
10
Q
When should a tinnitus patient be referred to mental health services?
A
- Suicidal ideation
2. Obvious mental health problems
11
Q
When can you forego referral to ENT?
A
- Tinnitus is linked to noise exposure
- Tinnitus symmetrical/non-pulsatile
- Tinnitus stable, long duration (6 months or more)
- Audiogram consistent with diagnosis of symmetrical, sensorineural hearing loss
12
Q
What are mental health disorders that commonly co-occur with tinnitus?
A
- Clinical depression
- Anxiety
- PTSD
- Sleep disorders
13
Q
What is residual inhibition?
A
Temporary suppression of tinnitus after a masking noise is played in their ear
14
Q
What is pseudohypacusis?
A
False hearing loss
15
Q
What is psychogenic?
A
Loss/disorder arising from psychological conditions; the patient is not aware that he is simulating deafness
16
Q
What is nonorganic?
A
Apparent loss with no known disorder or insufficient evidence to explaint it
17
Q
What is malingering?
A
Deliberately faking a loss
18
Q
Why would a patient present with nonorganic hearing loss?
A
- Adults seek financial or other gain (predominately male)
- Children (mostly girls) seek medical attention when they really need attention for an issue they cannot express
- Wish to avoid undesirable situation
- Attempt to place blame for inadequate social behavior on psychological disorders
19
Q
What are some signs of nonorganic hearing loss?
A
- Disagreement among test results
- SRT vs. PTA, Audiometric vs. AR thresholds, Air-bone gap in the wrong direction - Disagreement between test results and behavior
- Disagreement between test-retest reliability - greater than 10 dB
- No shadow curve in the unmasked results
- Odd repetition of monosyllabic words
- Odd results (repeating half of the spondees)
20
Q
What are some behaviors associated with nonorganic hearing loss?
A
- Exaggerated listening behaviors
- Smirking (if a kid)
- Avoiding eye contact
- Unwillingness to use own voice
- Over reliance on lip reading
- Inappropriate repetition of words
- Repeating spondees or monosyllabic words with questioning intonation
- Exaggerated or contradictory statements of difficulty or discomfort
- Vague description of hearing difficulties
- Volunteering of unasked for supplementary information
21
Q
How can you modify audiometric testing if you suspect malingering?
A
Use ascending rather than descending thresholds.
Present the monosyllabic word lists at 10 dB SL
Yes-No Test: patient tends to say “no” to tones below stated threshold
22
Q
How can you test a patient with a unilateral nonorganic hearing loss?
A
Stenger Test
When a listener is presented with the same type of sound in both ears, s/he will only hearing a single sound and hear it in the ear in which it’s louder
Part 1: Present 2 tones
- A +10 dB SL in good ear
- A -10 dB SL in “bad ear”
- If no response, you’ve caught them
Part 2: Reduce level in “bad” ear until they respond
23
Q
Inconsistent results may be due to…(non-organic hearing loss)
A
- Pt. doesn’t understand the test procedure
- Pt. is poorly motivated
- Pt. is physically or mentally incapable of appropriate responses
- Wishes to conceal a handicap
- Is deliberately feigning or exaggerating a hearing loss for personal gain or exemption
- Suffers from some degree of psychological disturbance
24
Q
What are conditions that mimic nonorganic hearing loss?
A
- Cortical deafness
- King-Kopetzky Syndrome
- Auditory Neuropathy Spectrum Disorder
25
Define sensitivity.
Percentage of persons with a disorder who show up on your test as having that disorder.
26
Define specificity.
Percentage of persons without a disorder who show up on your test as not having that disorder.
27
List the clinical uses for OAEs.
1. Universal newborn screening
2. Differential diagnosis
3. Monitor effects of treatment
4. Selection of treatment
5. Surgical options
28
List the research uses for OAEs.
1. Non-invasive window into intracochlear processes
2. Insights mechanisms and function of cochlea
3. New understanding nature of sensory impairment
29
Why isn't an OAE examination a test of hearing?
1. The patient can have a hearing loss, but still have present OAEs
2. It's not really hearing unless the patient states that they hear it
3. Presentation levels are loud, so OAEs are not a measurement of absolute threshold
30
When would you expect to find a hearing loss with normal DPOAEs?
1. There is damage to the inner hair cells
| 2. The hearing loss is neural
31
How can OAEs tell us about the site of lesion?
They can distinguish between sensory and neural hearing losses.
32
What are the advantages of OAEs?
Fast, simple, inexpensive
33
What are the disadvantages of OAEs?
High failure rate, does not detect Auditory Neuropathy Spectrum Disorder
34
What are the effects of the outer ear on OAE generation?
- Wax and debris can block sound delivery tube or microphone
- Leakage from improper fit
- Acoustics of the ear canal (are compensated by calibration prior to measurement)
35
What are the effects of the middle ear on OAE generation?
- Health of ME influences OAE recordings 2 times- forward and reverse propagation
- Reverse propagation is less efficient than forward- leads to a loss of 30 dB
36
What are the effects of the inner ear on OAE generation?
- Sensitive to loss of outer hair cells- can pick up dysfunction before audiogram
- Also affected by stria vascularis, which maintains the electrochemical balance necessary for normal OHC function
37
Why doesn't middle ear transmission work in reverse?
Mechanisms that aid impedance matching in forward transmission become impediment in reverse transmission.
38
What happens with negative middle ear pressure?
DPOAE levels reduced below 2 kHz, minimal effects at 2 kHz, variable effects are above 2 kHz
Introducing negative pressure can offset effects
39
What are the functional differences between OHCs and IHCs?
IHCs: sensory function; mediate conversion of mechanical energy to neural signals
OHCs: mechanical function; amplification for low-input signals
40
What are spontaneous OAEs?
Recorded without external stimulation.
SOAEs are equally spaced along basilar membrane
41
What is the relationship of SOAEs to hearing status?
Presence of SOAEs doesn't guarantee normal hearing
42
What are 2 possible mechanisms for SOAEs?
1. In normal hearing ears, SOAEs are the result of active cochlear mechanisms and global resonance in ear canal
2. Isolated, high-level SOAEs are associated w/ cochlear damage- artificial boundaries along the cochlear partition act as barriers or reflectors creating OAEs
43
What are the 2 types of evoked OAEs?
DPOAEs
TEOAEs
44
How do you measure TEOAEs?
Very short duration clicks (80 microseconds)
- Averaging cancels out click stimulus and leaves emission response to be analyzed and displayed
- Generate an average and see how well one average of sweeps correlate with the other average
- Look at amplitude
- Look at SNR
- Measures high frequencies first and then low frequencies
45
How do you measure DPOAEs?
Generated by 2 tones presented simultaneously
- Cochlea generates additional tones- distortion products- at frequencies arithmetically related to those of stimulus tones
- 2f2-f1 most commonly used in clinical practice
46
How do you measure stimulus frequency OAEs?
Record with probe tone at frequency of interest presented at 20-40 dB SPL.
Suppressor tone close in frequency is added to signal.
Presence suppressor tone removes SFOAE from 2nd recording.
Second recording is subtracted from first recording- let with SF emission
47
How is reverse propagation of OAEs initiated in cochlea?
1. Place Fixed
Reflections from random perturbations that are fixed n place along basilar membrane
2.Fixed to stimulus wave
Reverse transmission induced by distortion caused by the stimulus
48
What are the implications for clinical utility of OAEs?
1. Reflections and distortion source OAEs likely to manifest different dependence on cochlear pathologies
2. Uncontrolled mixing may be source variability in current OAE measurements
3. Unmixing strategies
49
What is the definition of the Nyquist theorem?
Highest frequency signal that can be accurately digitized by an analog-to-digital converter is one half the sampling rate of the device
50
How can you solve the number of bits required for a dynamic range?
Dynamic range= 20*log10 (2^n)
51
How can you check for OAE system distortion?
1. Conduct OAE test in an appropriately-sized cavity ~2cc
2. Most OAE systems include syringes for this purposes
3. The software reports noise floor and OAE levels
4. Under ideal conditions, no noticeable OAEs should be recorded above the noise floor
52
What are some methods for eliminating artifact?
1. Filter frequencies not in region of interest
2. Eliminate extra large signals
3. Repeatability
53
What are the goals of OAE calibration?
1. Present stimuli at precise, accurate levels
| 2. Accurate representations of OAEs, noise floor
54
Why doesn't a 2-cc coupler work for OAE calibration?
- Output heavily influenced by impedance of the load to which it is coupled
- Differences in ear canal anatomy, probe fit, depth of insertion significant between patient, between trials of same patient
55
What are 4 key factors for OAE testing?
1. Status of external and middle ear
2. Fit of probe within external ear
3. Stimulus characteristics and stability
4. Noise in test environment and within external ear canal
56
What are the 2 most important criteria for stopping OAE data collection?
Amplitude of OAE
Amplitude of Noise level
57
You should always first examine external ear canal before OAE testing except...
For patients who have just had otoscopic examination in medical facility
Newborn infants undergoing OAE screening
58
How can you deal with standing wave interference?
Highly atypical and unreliable amplitudes at 1 or more frequencies should be viewed with suspicion
Repeat calibration and measurement after probe reinsertion
59
What are the stimulus parameters for TEOAEs?
Type: clicks, tone-bursts, chirps
Intensity: default at 80 or 86 dB SPL
60
What are the stimulus parameters for DPOAEs?
High stimulus levels- more of a chance of detecting an artifact rather than actual OAE
L1= 65 dB, L2= 55 dB
These presentation levels increase amplitude of DPOAEs
Enhance sensitivity to cochlear dysfunction
61
What is the ideal f1/f2 ratio?
Usually around 1.22
Optimal f1/f2 ratio varies with age
62
How to evoke largest DP?
Evoked by tonal stimulation defined by 2 f1-f2
63
What are intensity parameters for DPOAEs?
Effective intensity levels range from 40 to 70 dB SPL
64
What are OAE stopping rules?
1. OAE amplitude level
2. Noise floor level
3. Signal-to-noise ratio
4. Maximum recording time
65
What are the objectives for OAE screenings?
Identify people who might have auditory disorder that interferes with communication
Pass vs. no pass
66
What are the objectives for OAE diagnostic testing?
Provide information regarding type, configuration, and site of auditory dysfunction
67
What are the JCIH recommendations for well-infant nursery?
Either ABR or OAE with repeat screening before discharge if first is a "no pass"
68
What are the JCIH recommendations for NICU?
Greater chance of neural hearing loss
Only recommends ABR
No pass- directly referred to audiologist
69
What are the test-retest reliability for DPOAEs and TEOAEs?
TEOAE: >90%
DPOAE: amplitude +/- 2 dB at least 2 runs
OAE noise difference >6 dB
70
What hearing loss would you expect with absent TEOAEs?
Hearing loss may be of mild to profound range
Enhanced sensitivity to OHC dysfunction even when audio is normal.
71
What are non-pathologic subject factors?
1. Time after birth
2. Time of bath- lower referral when time after bathing at least 7 hours
3. Age- OAE amplitude highest term birth
4. Sex: TEOAEs are larger in females
Lower referral rates for experienced testers and test frequencies above 2 kHz
72
What are the clinical applications of OAEs?
1. Monitor middle ear disease
2. Hearing screening
3. Monitor ototoxicity
4. Nonorganic hearing loss
5. SIDS
6. APD
73
What happens to TEOAE results if there is negative middle ear pressure?
- Amplitude decreases 2.5 dB at +100 or -100 daPa
| - Greatest changes in amplitude at extreme pressures but only for stimulus frequencies below 2 kHz
74
When would you expect decreased DPOAE amplitude?
- Hx of middle ear disease
- Severity past infection
- Can be present even with normal audiogram
75
What is OAE protocol for monitoring ototoxicity?
- Baseline audiogram including pure-tone audiometry, including high frequencies, tympanometry, DPOAEs
DPOAEs: 5 to 8 frequencies/octave up to highest test for frequency, 65/55 intensity paradigm
- Monitor every week to 2 weeks during administration of drug
- Monitor 1 week, 1 month, and 3 months after drug discontinuation
76
What are the criteria for change in auditory status?
- 15 dB decrease in pure tone AC threshold at 1 frequency or 10 dB decrease at 2 frequencies
AND/or
Decrease in DPOAE amplitude exceeding test-retest reliability (2 dB)
77
What are the applications for OAEs in adults?
1. Noise-induced hearing loss
2. Tinnitus
3. Meniere's disease
4. Intraoperative monitoring
5. Smoking
78
What is the function of OAE suppression?
Possible protection from noise exposure
Result suggests that strong activation of MOC with efferent suppression would result in less noise damage
79
What are the protocols for OAE suppression?
Ipsilateral, contralateral, or bilateral masking
- All 3 elicit an acoustic reflex, which will affect OAE level
- Suppression and reflexes operate under the same time scales so difficult to distinguish
- Contralateral has the smallest effect
- Broadband noise elicits the greatest suppression effect ~65 dB SPL
80
What are the barriers to clinical applications of OAE suppression?
- Lack clinical instrumentation for adequate presentation of contralateral, ipsilateral elicitor signals
- Lack clinically feasible algorithms for statistical analysis of abnormal vs. normal
81
For what pathologies is it possible to get a Type A tympanogram with a conductive hearing loss?
Otosclerosis
Malleus fixation
Severe scarring
Atrophy
82
If you don't have good bone-conduction data, what type of SNHL might mimic a conductive hearing loss?
Low-frequency SNHL
Meniere's disease
Some types of tumors
83
Why do we use a 226 Hz probe tone in tympanometry?
- Doesn't cause microphone nonlinearities
- Doesn't elicit acoustic reflexes at moderate intensities
- Is less susceptible to interference from power lines
84
What are stiffness components?
- Volumes of outer ear, middle ear spaces
- Tympanic membrane
- Tendons, ligametns of ossicles
85
What are components of mass?
- Ossicles
- Pars flaccida of eardrum
- Perilymph (inner ear)
86
What are components of resistance?
- Perilymph
- Mucous membrane linings of middle ear space
- Narrow passages between ME and mastoid air cavities
- TM, middle ear tendons and ligaments
87
What are the 3 variables of acoustic admittance?
Compliance
Mass
Friction-conductance
88
Why is multi-frequency, multicomponent tympanometry rarely performed in the US?
- Lack of equipment
- Lack of training fro performing
- Lack of training for interpreting
- Lack of time
- Equipment cost
- Clinical relevance
- Reimbursement
89
What are the 4 parameters that can be derived from multi-frequency tympanometry?
1. Resonant frequency
2. Frequency corresponding to an admittance phase angle of 45 degrees
3. Tympanometric configuration of Vanhuyse pattern
4. Static admittance
90
What is the 1B1G pattern?
- Standard low frequency tympanometry yields a 1B1G pattern
| - Ear is stiffness dominated
91
What is the 3B1G pattern?
Ear is stiffness dominated
92
What is the 3B3G pattern?
- Susceptance and conductance tympanograms each have 3 peaks
| - Either at resonance or mass dominated
93
What is the 5B3G pattern?
- Susceptance tympanogram has 5 peaks and the conductance tympanogram has 3 peaks
- Ear is mass dominated at higher frequencies
94
How do admittance components vary as a function of frequency?
- Acoustic conductance (frictional component) is independent of freuqency
- Both compliance and mass susceptance are frequency dependent
Mass susceptance is diretly proportional to frequency
Compliance susceptane is inversely proportional to frequency
95
What are the clinical limitations of WBFT?
- Standing waves at higher probe frequencies can cause artefactual notches
- At 1 and 2 kHz, reliability can be poorer than at lower frequencies
- Complex notching patterns can be difficult to interpret
- Large overlap between normal and pathologic ears
96
What are the benefits of WBFT?
- Potential for detection of otosclerosis
| - Resonant frequency can better trace the resolution of the fluid in the middle ear than convention 226-Hz tympanometry
97
How is reflectance different than tympanometry?
- Acoustic impedance of the sound source is determined prior to measurement in the ear
- B/c the sound source has already been calibrated, the static pressure in the ear canal doesn't need to be altered
98
What does it mean when there is low reflectance value?
Most of the sound power is transmitted to the middle ear
99
What does it mean when there is a large reflectance value?
Most of the sound power is reflected from the middle ear
100
What is the advantage of wideband reflectance vs. MF tympanometry?
Location of probe in the ear anal is not as critical, especially at higher frequencies
101
What is attributed to largest variability in wideband reflectance?
Poor fit of probe in ear canal
Can be minimized through proper insertion
102
What are the anatomical differences between infant and adult ears?
1. More compliance in ear canal wall
2. Small ear canal and middle ear space
3. More horizontal orientation of the TM with respect to the axis of the ear canal
103
What are developmental changes of the middle ear in the first 6 months after birth?
1. Increase in diameter, length, and orientation of ear canal
2. Increase in rigidity of the ear canal
3. Change in orientation and thickness of TM after birth
104
Why is a 226-Hz tympanometry not an effective test for ME measurement in newborns?
- In neonatal ears with confirmed ME disease, 226-Hz tympanograms are not reliabily different from those obtained from normal ears
- Tympanometry using higher probe-tone frequencies is more sensitive to change in ME status
105
Why should special caution be used when presenting high-level stimuli to the ear canal in infants and children for reflex testing?
- Potential risk of permanent threshold shift
| - SPL developed in smaller ear canal can be at least 10 dB higher than in an adult ear
106
What are some common wideband reflectance results in children?
- 1-month old infants have lower energy reflectance values than adults for responses below 700 Hz
In the high frequencies, adults have smaller energy reflectance values than newborns
107
For what pathologies are reflectance curves shifted to the right?
Otosclerosis
Stiffening pathologies
108
For what pathologies are reflectance curves shifted to the left?
TM perforation
Ossicular discontinuity
Loosening pathologies
