5343 Praxis Flashcard

What is the relationship between fundamental frequency and harmonics?

Fundamental Freq \= the lowest freq of a periodic waveform (F0)

Harmonic \= the regualr and repeating multiple of F0

In what freq and what intensities are most speech sounds produced

125 Hz - 8k
or 250 - 4000 (speech banana)

intensity: 55-65dB

Threshold

Lowest level at which responses occur in at least 1/2 of a series of ascending trials

What is the relationship between SPL and HL

HL normalizes SPL scale to 0

SPL necessary tp achieve 0dB HL is greatest a LF, lessens in the middle freq, and increases at HF

What is the function of the Outer Ear

Funnels sound and localization

ITD & ILD cues

Acoustic

What is the function of the Middle Ear?

Reduces impedance mismatch & protects from loud sound

Ossicles, ET, pressure equalization

Mechanical

What is the function of the Inner Ear?

Frequency selectivity - tonotopic

Balance maintenance

Electrical

at 1000 Hz 0dB SPL \=

7dB HL

Outer Hair Cells (OHC)

Cochlear Amplifier -
efferent signal
embedded on TM
3 rows

Inner Hair Cells (IHC)

Signal detection - sensory
Afferent Signal
Not embedded on TM
1 row

Endolymph

Fills the Scala Media and SSC's
K+

Perilymph

Scala Vestibuli
Scala Tympani
Na+

Impacts of hearing loss for children

Delay in speech and language, reduced academic achievement and vocabulary, lessened literacy skills, social isolation and poor self-concept, vocational choices

Pre-lingual

before language was acquired
- start CI eval process ASAP

Post-Lingual

after language was acquired
- about age 6

Impacts of Adult HL

fatigue, depression, social withdraw, impaired memory, reduced quality of life, headaches, increased stress and blood pressure

What are the etiologies of hearing loss present at birth?

50% Genetic (30%syndromic - 70% Non-syndromic)
25% Environmental
25% Idiopathic

Non-syndromic:

Connexin mutation related
BFN B4
Mitochondrial

Syndromic:

Alport syndrome
Branchio-oto-rental syndrome
CHARGE
Jervel and Lange-Nielson Syndrome
Pendred syndrome
Treacher Collins syndrome
Stickler syndrome
Ushers syndrome
Waardenburg syndrome
Down syndrome, Neurofibromatosis type 2

gap junction beta 2 (GJB2)

encodes co cx26 protiens

Connexin 26

found in the cochlea, support cells, and stria vascularis

mutation: varies from mild - profound HL

connexin 32

x - linked

Usher syndrome

type 1: (90%) retinitis pigmentosa by 10, profound congenital HL, Absent vestib

Type 2: (10%) retinitis pigmentosa by 20's, Mod progressive HL,nrom or dec vestib

Type 3: (

Waardenburg Syndrome

Autosomal dominant,
color irises, white forelock, defective or absent organ of corti, reduced AN fibers

Jervell & Lange-Nielsen Syndrome

Autosomal Recessive
primarily a cardiovascular disorder
congenital bilateral (profound usually) HL
family history of sudden death

Teacher Collins syndrome

Autosomal Dominant
All types of HL
Auricular deformities
Ossicular malformations
Facial Bone abnormalities

CHARGE syndrome

Coloboma - missing segment of eye
Heart
A choanae - blocked nasal package
Retardation - of growth & development
Genitourinary - genital / urinary problems
Ear - norm (15%) mild-mod (38%) severe-profound(47%)

Neurofibromatosis

Autosomal Dominant
Type 1 - cafe au lait spots - tumors of the brain etc

Type 2 - bilateral acoustic neuromas

Pendred syndrome

Autosomal Recessive
deficit in ion transportation in endolymph reabsorption
U-shaped audio, high freq SNHL
HL noted by age 2
progressive

Apert Synddrome

Autosomal Dominant
flat cHL - often bilateral
maybe SNHL - malformed cochlear aqueduct

Down Syndrome

Bilateral CHL or Mixed
lateral ET
Shortened ABR interwaved laterncies

Brachio-oto-retnal syndrome

Melnick-Fraser syndrome
Sensorineural, conductive, or mixed & can be progressive or permanent at birth. Can cause ossicular fixation or cochear hypoplasia. Kidney abnormalities!

Marfan Syndrome

ong arms, legs, fingers & toes. Heart defects. CHL & recurrent ear infections. Hypertention can also cause SNHL.

Goldenhar syndrome

Abnormal development of the eye, ear and spine. Usually ONE SIDED atresia (missing ear canal) and MISFORMED OSSICLES! Usually normal inner ear.

Noonan syndrome

Low-set ears. SNHL in up to 50% of patients. Short stature, heart defects

Types of Presbycusis

Sensory
Neural
Metabolic
Mechanial

Sensory Presbycusis

hair cells. Initially affects the outer row of OHC in the basal turn. Secondary degeneration of auditory nerve fibers occurs.Lipofuscin (age pigment) accumulates in cochlea cells.

Neural Presbycusis

auditory nerve. Histology shows loss of \>50% of cochlear nerve fibers, with greatest loss in the basal turn.Speech recognition performance is lower than expected from audiogram. 90% of fibers must be lost before threshold decreases

Metabolic Presbycusis

(atrophy of stria vascularis): Stria generates energy and nutrients for the cochlea; stria loss reduces cochlear function. Flat audiometric configuration

Mechanical Presbycusis

(stiffening BM): cochlear conductive HL. The assumption is that structural changes in the basilar membrane and/or spiral ligament occur with age. Hearing loss has a shallow slope and no histologic evidence of cochlear or neural damage

Why does fluid accumulate behind the TM in the middle ear space during otitis media?

An ear infection is caused by a bacterium or virus in the middle ear. This infection often results from another illness — cold, flu or allergy — that causes congestion and swelling of the nasal passages, throat and eustachian tubes. Swollen eustachian tubes can become blocked (eustachian tube dysfunction), causing fluids to build up in the middle ear (effusion). This fluid can become infected and cause the symptoms of an ear infection

Chronic OM

Presence of fluid for more than 30 days

Recurrent Acute OM

3 or more bouts within 6 months

Chronic Suppurative OM

Persistent inflammation and disease of the middle ear

Honey colored TM

chronic OM with effusion

Red & Bulging TM

acute OM

the condition associated with bony growth surrounding the bones of the middle ear and describe the type of hearing loss that accompanies it.

Otosclerosis. CHL.
Can be congenital or acquired (through perf or constant negative pressure)

NO CONSISTENT TYMP PATTERNS, DEPENDS ON DEGREE OF OSSICULAR CHAIN INVOLVEMENT

Bacteria often associated with the mass!

What are the key precautions used to achieve infection control?

-appropriate personal barriers (gloves, masks, etc) worn when performing procedures that may expose you to infectious agents-hand hygiene performed before and after patient contact and after glove removal, before and after eating-touch and splash surfaces must be pre cleaned and disinfected-critical instruments sterilized-infectious waste disposed of appropriately-dispose of speculums-disinfect equipment

Disenfection

eliminating / reducing harmful microorganisms (decontaminate surface & air

Sterilization

eliminating all microorganisms (food medicine surgical instruments)
- done with bodily fluids

What equipment is used to measure noise in a classroom

Sound level meter
(type 2)

What are the guidelines for acceptable noise levels OSHA?

requires employers to implement a hearing conservation program when noise exposure is at or above 85 decibels averaged over 8 working hours, or an 8-hour time-weighted average (TWA), which is a combination of all the sound intensities throughout the work shift.

At 90 dB for 8 hours, the noise has reached the PEL (permissible exposure level), and hearing protection is warranted.

Hearing protection required at 90 dB TWA & 85dB TWA with previous STS

NIOSH (National Institute for Occupational Safety and Health)

3 dB exchange 85 8 hrs 88 4 hrs etc

Equivalent Continuous Sound Pressure Level LAeq

the constant noise level that would result in the same total sound energy being produced over a given period.

A fundamental measurement parameter designed to represent a varying sound source over a given time as a single number.

in 1 hour you reach 100% noise dose at whatever LAeq is

Describe different types of hearing protection and the importance of their fit for effectiveness.

Disposable foam earplug: provides the most attenuation, but attenuation depends highly on fit.

Premolded, disposable earplug: attenuation depends on fit, correct size, can fall out when chewing/talking.Banded earplugs: lower attenuation than most earplugs. Convenient to put around neck.

Custom earplug: lower attenuation. Can attach to radio.Passive earmuff: Good for intermittent noise

Earmuffs with radio or amplification: Better compliance, allow communication, better for low levels of noise, manage impulse noise

level dependent devices: Communication and situational awareness in certain situations

Combined hearing protection and communication systems: allows for communication in loud environments

Which provides the best hearing protection
silicone vs foam vs silicone w/ filters vs passive circumarual earmuffs

solid siliconeee

Describe testing instrumentation that can be taken into the workplace.

SLM: used for particularly noisy areas, near a machine. Type 2 can be used for most HCPs. Can be used to make a "noise map." Do not necessarily measure an individual's noise exposure.

Noise dosimeter: SLM that is worn on the body; log an employee's noise exposure.

Benefits of a baseline audio

Having a reference for future audiograms and can determine if the patient experiences a change in hearing sensitivity.

Should be obtained within 30 days of starting work in a noisy area.

Test after 14 hours after a noise-free-period.

standard threshold shift

threshold change of 10 dB + at 2, 3, and 4kHz in one or both ears

Injury

occurs suddenly
- acoustic trauma

Illness

More gradual
- long term noisy job

Describe the screening protocols recommended for screening adults and children. How do they differ?

For those children who can be conditioned for visual reinforcement audiometry (VRA), screen using earphones (conventional or insert), with 1000, 2000, and 4000 Hz tones at 30 dB HL.

For those children who can be conditioned for play audiometry (CPA)--up to age 18--, screen using earphones (conventional or insert), with 1000, 2000, and 4000 Hz tones at 20 dB HL.

Adults: Position conventional earphones (or insert earphones) and present pure tones at 25 dB HL at the frequencies of 1000, 2000, and 4000 Hz.

Describe follow-up procedure for a person who has not passed a hearing screening?

ABR babies get re-screened once only. Never OAE screen after ABR because you'd miss ANSD.

OAE babies get one re-screen in hospital and one outpatient re-screen

What do the Joint Committee on Infant Hearing recommendations require in terms of timing and screening requirements?

1-3-6 screen, diagnose, intervention

What are the most common screening tools in newborn screenings? List pros and cons

OAE: Quick, Placement of probe prone to be failed compare to ABR.

ABR: Testing retrocochlear area. Neural function and more informations on hearing loss. Not recommended for NICU bc ANSD risk factor.

Describe the differences in results from OAEs versus ABRs in newborn screenings.

OAE: frequency specific \>1k.

ABR: stimulus\= clicks or chirps. click is 1-4k. Level is 35 dB (would not detect LF hearing loss.)

What different kinds of self-report measures can be used with patients and what patient factors should be taken into account in selection and interpretation?

COSI
APHAB
HAsHAPI
SADL
IOIHA
SSQ

COSI

open ended
choosing listening siuations

APHAB

disability by HL and reduction of disability with

HAsHAPI

assesses effectiveness of Amp in everyday listening siuations

SADL

4 subscales of cost, positive effect, negative features, and personal image

IOIHA

satisfaction and QOL changes with HA use

SSQ

several domain of auditory disability and handicap

Longitudinal fracture

CHL

Transverse fracture

SNHL

List the key components of a case history

Chief complaint/reason for coming
Concerns with hearing: degree, onset, cause, length of time with HL, which ear, fluctuations/progression?
Dizziness & ringing?
Previous hearing tests?
Noise exposure
Family history of HL
Medical history: surgery on ears, pain, drainage, fullness, visual disturbances
HA history

pediatric case history

Pre-natal history, birth history (born full term? complications?) and NICU stay, passed HBHS?, general health/ear infections, family history of childhood hearing loss, S/L development, global development, educational concerns, hearing concerns??

What steps need to be taken to verify the different kinds of assessment equipment?

\#1: Annual electroacoustic calibration (does not exist for OAE & ABR)

\#2: Biological checks... self-listening check & hearing threshold check (audiogram on someone with "known and stable" thresholds.

Daily biological/listening checks.... when should you do this? why should you?

When? Before using new equipments, daily or some other regular interval

Why? To detect problems prior to obtaining clinical data & monitor the status of your equipment

Steps for biological check

1. Phone check... play a continuous pure tone, reduce and increase (check for noise).

2. Bone oscillator check... across frequencies at 30 dB and 50 dB for distortion

3. Audiometer check (are dials loose? Listen for background noise in between signals)

4. Threshold check (on chair in booth)

5. Tymp: 2cc on volume measures on tymp. should easily obtain a sea

When to use a 1000 Hz tymp

Below 9 mo - but if you see a dip in the peak move to 226 (this usually occurs 6-9 months)

determine appropriate assessment for...Physiologic measures rather than behavioral assessment?

Children who can not give reliable behavioral results

determine appropriate assessment for...Use of different kinds of behavioral assessment?

CPA, VRA, BOA. Children or adults with developmental disabilities

determine appropriate assessment for...Use of different kinds of stimuli?

Tinnitus, bored children, people with CI need broadband noise

Degree of HL classifications

Normal: -10 to 15
Slight: 16 - 25
Mild: 26 - 40
Moderate: 41 - 55
Moderately severe: 56 - 70
Severe: 71 - 90
Profound: 91+

A primarily hereditary, progressive disorder where the stapes footplate becomes partially fixed to the oval window.

otosclerosis

carhart's notch

stapendectomy

carhart's notch

normal bone... air is worse at lower frequencies, rises to meet bone at 2k, and then get's worse again. Unilateral.

supraaural headphones

easy to calibrate, could cause collapsing ear canals. lower inter-aural attenuation (easier for sound to travel from one ear to the other). Worse for high frequencies. Better for lows.

What is the warble tone? Why is the warble tone used when testing in the sound field?

A tone whose frequency varies periodically several times per second over a small range; used to prevent standing-wave patterns from forming in reverberation chambers: when the vibrational frequency of the source causes reflected waves from one end of the medium to interfere with incident waves from the source.

What tone do you never use in sound field

pure tone

SAT

The lowest level at which the listener can just detect speech (but not understand it). To compare with the best pure tone threshold (i.e., cross-check with audiogram). Use with young children or developmentally delayed patients who cannot point to pictures or repeat words for the SRT.

SRT

The lowest level at which the listener can just detect speech (but not understand it). To compare with the best pure tone threshold (i.e., cross-check with audiogram). Use with young children or developmentally delayed patients who cannot point to pictures or repeat words for the SRT.

Having obtained a reliable SRT, how would you estimate MCL?

typically 50-55 dB above SR

At what level is a word recognition test administered?

MCL/ 50-60 dB for normal hearing patients, for patient with hearing loss\-- 20-30 dB SL the poorest air conduction threshold in the test ear from 1000-4000 Hz OR 20-30 dB SL the SRT

What are the phonetically balanced word lists used for?

Word recognition testing. Single-syllable words (CVC) that are phonetically balanced, meaning the beginning and ending phonemes are chosen according to their frequency of use in conversational speech

Discuss the pros and cons of MLV vs. recorded

MLV can be personalized. Recorded is more consistent and more standardized. MLV can be paced however is needed. Accents are a barrier (could be different than local dialect with either presentation). Recorded voice presents normative data (helpful when fitting).

appropriate testing methods: 0-6 mo

BOA or ABR

appropriate testing methods: 6 months-2.5 years:

VRA

appropriate testing methods: 2.5 - 5 years:

CPA

Speech testing for ages