Exam 2 Priority Flashcards
List 8 warning signs of ear disease that should be referred for medical evaluation before proceeding with amplification?
- Visible congenital or traumatic deformity of the ear.
- History of active drainage from the ear within the previous 90 days.
- History of sudden or rapidly progressive hearing loss within the previous 90 days.
- Acute or chronic dizziness.
- Unilateral hearing loss of sudden or recent onset within the previous 90 days.
- Audiometric air-bone gap equal to or greater than 15 decibels at 500 hertz (Hz), 1,000 Hz, and 2,000 Hz.
- Visible evidence of significant cerumen accumulation or a foreign body in the ear canal.
- Pain or discomfort in the ear.
act as a frequency specific volume “handle” to maximize audibility w/o changing compression
Frequency shaping bands
Define Frequency shaping bands
Frequency shaping bands acts as frequency specific volume “handle” to maximize audibility without changing compression
adjust compression ratios to shape output into the individual’s dynamic range
Compression shaping channels
Define Compression shaping channels
Compression shaping channels adjust compression ratios to shape output into the individuals dynamic range
The measurement of the absolute SPL level of an open ear canal resonance, across all frequencies, at the tympanic membrane (input+ gain+ resonance= output)
Real ear unaided response (REUR)
Measures the natural amplification created by the shape of the pinna & open ear canal.
Real ear unaided response (REUR)
Clinical Usefulness of REUR
Knowing an individual’s ear canal resonance improve accuracy of prescriptive fitting
REUR changes due differences in:
- Size, texture, shape, or presence of abnormal anatomy
- Age: Pediatric, adult, elderly
- One person can have 2 different REUR’s
Define REOR; Real Ear Occluded Response
A measurement of insertion loss caused by placing an earmold/dome in the ear canal.
The measurement of gain increase resulting from pinna, ear canal, and head diffraction effects, as measured in an open ear canal.
REUR - input level =
REUG; Real Ear Unaided Gain
A measurement of insertion loss caused by placing an earmold/dome in the ear canal.
REOR; Real Ear Occluded Response
A measurement of the attenuation of an input signal, across all frequencies, when a hearing aid is inserted and turned off
REOR; Real Ear Occluded Response
Clinical usefulness for REOR
- This measurement identifies which low frequencies are released due to the vent effect
- Programming tip: You will not be able to increase the output within the “vent effect” frequency range. Additional gain is be released through the vent!
- The measurement shows if the vent introduced undesired standing wave effects that would impact amplification characteristics?
- i.e., Vent-associated phase cancellation
What does REOR tell us
REOR tells us…
If the vent effect is releasing low frequencies as expected
If an open dome truly “open” (acoustically transparent”)?
- Large domes fold in small ear canals causing insertion loss
If closed vents or power domes supply needed LF gain?
- Research on power & closed domes suggests LF output is compromised in low and mid frequencies for losses > 35 dB HL
- It’s possible for an unexpected slit leak in an unvented mold to release of LF output
REAR; Real Ear Aided Response
The absolute aided output and frequency response when a hearing aid is turned on
The absolute aided output and frequency response when a hearing aid is turned on
REAR; Real Ear Aided Response
Clinical Usefulness of REAR
Why we do it …
To view device’s absolute aided output in a unique ear canal
- If you don’t measure it, you
don’t know if you’ve met your
objective!!!
DSL prescriptive targets specifies REAR (OUTPUT) targets for signals arriving to the TM
Assessment of MPO
REAR 85/90 (MPO); Real Ear Aided Response 85/90 (REAR85/90), AKA MPO,
REAR 85/90 (MPO); Real Ear Aided Response 85/90 (REAR85/90), AKA MPO,
Measures intensity of the output signal arriving at the TM, when the input signal is sufficiently intense to drive the device to its maximum power output level.
Measures intensity of the output signal arriving at the TM, when the input signal is sufficiently intense to drive the device to its maximum power output level.
REAR 85/90 (MPO); Real Ear Aided Response 85/90 (REAR85/90), AKA MPO,
REAR 85/90 (MPO) Clinical Usefulness
To document the maximum SPL that the hearing aid can deliver to the user’s ear for loud sounds
To ensure MPO settings do not exceed loudness discomfort levels
REAR 85/90 uses what type of signal?
Type 1 input signal
______ is the difference in decibels across frequencies, between an ear canal resonance and the resonance of the 2cc coupler
RECD; Real Ear to Coupler Difference
Define RECD
A sound generating transducer produces a signal in the ear canal and in a 2cc coupler to measure the resonance of each.
RECD is the difference in decibels across frequencies, between an ear canal resonance and the resonance of the 2cc coupler
Name two reasons for RECD measurement
- Accurately converts an individual’s HL audiometric thresholds, measured using inserts, to dB SPL values
- Arguably the most useful application of the RECD is in the prediction of real-ear output when hearing aid measurements are made in the test box.
the natural resonance resulting from the pinna and ear canal effect that the patient walked in the door with
REUR
the insertion loss that results from the mold/dome
REOR-
the output arriving to the TM when aid is turned on
REAR
the amount of gain added to the input signal when the aid is turned on
REIG
the MPO that’s arriving to the TM
MPO/RESR/REAR85/90
the difference between the SPL resonance of a 2cc coupler and the SPL resonance of the real ear
RECD
Digital technology is best measured with standardized __________
type II signals
True or False
Type II signals are pure tone signals swept over a variety of frequencies
FALSE
Thats type 1
Type II signals are complex “speech-like” signals
Pure tone signal swept over a variety of frequencies
Type I Test signal
Type I Test SIgnal
Pure tone signal swept over a variety of frequencies
TYpe II Test Signal
Type II signals are complex “speech-like” signals
Broadband signal consisting of random frequencies occurring at different intensities
Type II Test Signal Benefits
Its unpredictable moment-to-moment amplitude changes mimics speech