SLP 440 midterm

In-the-Ear (ITE):

mild-moderatively severe HL; built in custom-made shells obtained from an impression of the patient's ear; not typically for pediatric use because they must be replaced as the ear grows

In-the-Canal (ITC):

mild-moderately severe HL; fits in the ear canal and custom fit; not typically for pediatric use because they must be replaced as the ear grows

Completely-in-Canal (CTC):

mild-moderate HL; custom-made shell obtained from impression; extends deeper toward the eardrum, making it the least noticeable

Receiver-in-the-Canal (RIC):

mild-moderately sever HL; suitable for older children with high frequency loss; discrete receiver wire with CIC mold makes it more cosmetically appealing than BTE

Behind-the-Ear (BTE):

all types and degrees of HL and for persons of all ages; customized earmold anchors the hearing aid to the ear and sends sounds into the canal; most appropriate for pediatrics due to rapid growth of ears; expensive to remake; MOST POWERFUL

Hearing Aid Candidacy:

appropriate for individuals w/ HL that cannot be medically or surgically remediated

Binaural Fittings:

both ears; most individuals with HL benefit from wearing 2 HAs → improves listening in background noise/speech and helps in sound localization/Bimodal stimulation: hearing aid in one ear and cochlear implant in another

Fitting Protocols:

selection of device, quality control, orientation/fitting, and validation with outcome measures → VITAL FOR SUCCESSFUL HA FITTING

-Must insure the wearer or caregivers (pediatrics) know how to remove and work the controls, troubleshoot, listening check, care for, and clean HA

Bone Conduction Aids:

usually used because of a congenitally absent or incomplete ear; patient must have normal or near normal bone conduction scores

Cros:

we use cros on a dead ear and put hearing aid on both ears, sound transmits from one side (dead ear) to the good ear so we can hear sounds from dead ear side; receiver receives and delivers sound on better ear and microphone is off; w/in normal limits; no localization ability

BAHA

bone anchored hearing aid, put BAHA on dead ear, skull will vibrate as a whole and better cochlea will respond which will help individual hear sounds from dead side of ear (helps with single sided deafness or hearing impairment) ex: ppl with bilateral atresia would benefit from BAHA; no localization ability; vibration implanted in bone, mic and amplifier are on external aid, requires relatively good cochlear hearing

BiCros:

exactly like the cros, but one ear is a dead ear and the better ear has mild-to-severe hearing loss; receiver receives, amplifies, and delivers sound, and microphone is on; suitable for SNHL; no localization ability

- Those with single-side hearing loss can choose between Cros, BiCros, BAHA, and cochlear implant

Special Hearing Aid Features:

-Telecoil

-Directional Microphones

-Noise Reduction

-Data Logging

-Multiple Programs

Telecoils

enables telephone use in HA by turning mic off; picks up electromagnetic signal from telephone and converts it to amplified sound

Directional Microphones

1+ microphones; identify what direction sound is coming from; helps gain speech understanding in loud environments

Noise Reduction

recognize background noise and reduces it

Data Logging

keeps track on how and when the patient uses the HA (helps with counseling)

Multiple Programs

set special settings (ie. noise reduction) based on setting or location

HA basic components:

microphone, amplifier, and speaker (reciever); Microphone transmits sound → electricity; receiver uses electricity to amplify sound

What does a T-coil do in a hearing aid?

-Microphone picks up sound (acoustic signals)

-T-coil replaces the mic and picks up electromagnetic field like from a phone when wearing a hearing aid, does not pick up sound, or any other environmental sound

-Multi memory and logs data

-"An option on the hearing aid where it switches to T-coil when its using a phone, which means it replaces the microphone and instead of picking up acoustic noise, it picks up electromagnetic field from the speaker (like when you move metal things with a magnet under the table)"

(+Bluetooth is a better option now technically, but not relevant for the test and t-coil is also still used)

How can earmolds acoustically change the output of sounds?

through changing the length or making the vents larger or smaller

Earmolds (used with BTE Has)

-anchors the hearing aid to the ear

-earmolds and all in-ear HA are often molded to fit the client's ear and couple the hearing aid to the ear (allows for specific modifying for individual)

Can use the earmold's style, tubing, venting, and damping to change the sound going into the ear by

changing venting length, tubing size, etc. can modify sound by changing the acoustics

why does feedback occur in a hearing aid fitting?

-Microphone gets too close to speaker, feedback happens when it amplifies itself (feedback acoustic loop)

-To help prevent feedback, ear mold must be separated from speaker

What is a cochlear implant?

-Offers an alternative for sound stimulation to individuals who receive limited benefits from traditional amplification

-Careful evaluation by a team of professionals determines candidacy and develop appropriate treatment plans (speech processor programming and training)

-Made for patients with profound (sometimes only severe) SNHL

-Must prove little or no benefit from traditional HAs before consideration

-Hole is punched into cochlea, destroys hair cells (since cochlea is embedded in bone, so electrode is wired around it)

team leaders for a cochlear implant:

-Otolaryngologist (surgery and medical decisions) and Audiologist (determines audiologic candidacy and programs the processor)

-Team also includes SLP, teachers, social workers, parents

(history of cochlear implant) in 1972 the first wearable implant was implanted in..

an adult at the House Ear Institute

(history of cochlear implant) The House/3M device consisted of a single:

electrode placed in the basal end of the cochlea

(history of cochlear implant) Over 1,000 individuals received the device, in 1980..

it became available for children over 2 years old

(history of cochlear implant) in the 1980's multi-electrode devices brought..

more but limited frequency cues. Many people were able to achieve open-set speech understanding (list and repeat back correctly)

How do cochlear implants work?

1. sounds are picked up by the microphone

2. the signal is then "coded" (turned into a special pattern of electrical pulses).

3. These pulses are sent to the coil and are then transmitted across the skin too the implant

4. the implant sends a pattern of electrical pulses to the electrodes in the cochlea

5. The auditory nerve picks up these electrical pulses and sends them to the brain. The brain recognizes these signals as sound.

(Ear-Level or Body-Worn speech processor - with battery source)

Microphone:

picks up the sound wave, converts it to an electrical signal and sends it to the speech processor

speech processor:

codes the information using a device-specific strategy and sends it to the external transmitter coil

Transmitter coil:

body worn or at the ear; has a magnet that adheres to the head over the skin where the receiver stimulator is placed → T-coil sends the information through the skin via FM radio waves to an internal receiver

Surgically-Implanted internal receiver:

sends the information to the implanted electrodes that stimulate the available auditory nerve fibers → attached to electrode arrow that is placed in the cochlea

Is a cochlear implant attached to the head?

no, attaches to a magnet

How we program cochlear implants:

-initial fitting and programming (hook-up) takes about 1 ½ -2 hours. To create the program, an audiologist has to determine electrical dynamic range for each electrode. Programming system (MAP) delivers an electrical current through the cochlear implant system to each electrode in order to obtain the electrical threshold and maximal level of current that is comfortably loud. Speech processor is programmed using one of the encoding strategies so the electrical current delivered to the implant will be within T and C- Levels

In order to create the program or MAP, for speech processor:

the audiologist must determine the electrical dynamic range of each electrode used.

Neural Response Telemetry:

allows implant system to function as miniature evoked potential system by sampling and recording action potentials generated by electrical stimulation.

(NRT, NRI, and ART offer a means of testing the compound action potential of the nerve)

Programming follow-ups for adult patients with postlingual hearing loss usually consists of:

Approximately six visits in the first two months of use, then at three months, six months, and

annually after.

programming follow-up for children is:

weekly visits for two months using two of the electrodes in the array as recording electrodes and two as stimulating electrodes.

T-Level:

minimum stimulation level is the softest electrical current which produces an auditory sensation 100% of the time.

-C-Level: loudest level that can be listened to comfortably for a long period of time.

When we program the cochlear implant:

-Patient has to undergo 4-6 weeks of healing and then goes through rehabilitation to program and adjust the CI, after T and C-levels are established and MAP created, the microphone is activated.

-Follow-up programming within one week of hook-up. Children often react with tears considering they have no concept of sound and hearing which may be frightening.

-Have a team approach when programming (2 audiologists)

-Candidacy for CI depends on if you receive limited benefits from amplification

Criterion for adults:

≤50% speech recognition in the ear to be implanted when listening at normal levels to sentences on the HINT (hearing in noise test: how well you can hear when the noise gets louder and louder) in the best aided conditions; The opposite ear must have ≤60%.

criterion for children 12-24 months:

bilateral profound SNHL ≥ 90 dB with limited benefit from traditional amplification

criterion for 24 month-18 years old:

≥70 dB with limited benefit from traditional amplification

3 companies that are approved by the FDA:

Cochlear:

Advanced Bionics: swimming

Med-El: MRI are feasible

-Both MED-EL and Cochlear Corporation have active clinical trials investigating the benefits of electro-acoustic stimulation. The term Hybrid© cochlear implant refers to the Cochlear Corporation system, whereas MED-EL simply refers to it as electrico-acoustic stimulation.

Auditory training methods such as speech tracking are extremely helpful in both treatment and:

monitoring the progress with the device (CI).Various therapy materials are available to the clinician through each of the implant manufacturers.

Cochlear implant is only one that helps with:

localization if the person has single sided deafness

Times of when the cochlear implant must be put on:

-The patient must wait approximately 2 to 3 weeks before the external head-set and speech processor can be fitted

-The waiting period allows for healing of the incision area prior to placing the magnet on the sensitive surface where the external transmitter is placed

Best Results:

Late Deafened adults: w/ oral communication skills and recent memory for sound

Young children: 1.5 years old and up; brains = malleable and therefore best candidates

When and why we mask:

to rule out participation of non-test ear by using a competing sound

symbols on audiogram:

(use diagram, can't copy symbols on computer)

What types of hearing loss affect speech discrimination/intelligibility the most:

SNHL-loss can affect the brain's ability to understand speech

know which of the speech frequencies are on an audiogram and what they represent

Refers to the "speech banana", which is the part of the audiogram (sound levels and frequencies) where speech sounds lay

slight hearing loss:

16-25 dB

Mild

26-40 dB

Moderate:

41-55 dB

Severe:

70-90 dB

Profound:

90 dB and up

Carhart's ideas on aud. training:

Carhart recommended that auditory training with adults focus on reeducated, a skill diminished as a consequence of the hearing loss. Initially felt that it was important to establish “an attitude of critical thinking”

Carhart considered auditory training to be

-a process of teaching the child or adults with hearing impairment to take full advantage of available auditory clues. As a result, Carhart recommended an emphasis in therapy on developing an awareness of sound, gross discrimination of nonverbal stimuli, and gross and fine discrimination of speech.

-Carhart's approach to auditory training for prelingually impaired children was based on his belief that since listening skills are normally learned early in life, the child possessing a serious hearing loss at birth or soon after will not move through the normal developmental stages important in acquiring these skills

Carhart outlined 4 major steps in auditory training for children with pre lingual deafness:

1. Development of awareness of sound (having the child acknowledge the presence of sound and its importance in his or her world)

2. Development of gross discriminations (initially involves demonstrating with various noisemakers that sounds differ)

3. Development of broad discriminations among simple speech patterns (once the child can successfully discriminate grossly different sounds, he or she is exposed to finer types of discrimination tasks that include variation in the frequency, intensity, and durational properties of sound)

4. Development of finer discriminations for speech (final phase consists of training the child to make fine discriminations of speech stimuli in connected discourse and integrating an increased vocabulary. Carhart also felt that the use if vision by the child should be encouraged in most auditory training activities)

Carhart advocated that auditory training sessions for adults be conducted in

three commonly encountered situations

1. Relatively intense background noise

2. The presence of a competing speech signal

3. Listening on the telephone

According carhart, the use of hearing aids (and cochlear implants) is vital in

auditory training, and he recommended that they be utilized as early as possible in the auditory training program

deaf:

hearing aids do not work as there is no sound to amplify, extensive hearing loss who cannot use hearing for the ordinary purposes of life

pre-lingually deaf:

born deaf or acquire it in the first five years of life

Perilingually deaf:

who acquired deafness while acquiring a first language

postlingually deaf:

who acquire hearing loss after age 5 through the school years

deafened:

who acquire hearing loss after their education is completed

heard of hearing:

those with milder forms of hearing loss

role of medical intervention in Aural rehab, if any:

Audiologic Rehabilitation does not include closely related medical intervention or the teaching of academics to the deaf

dynamic range:

Difference between softest you can hear something and the loudest you can hear something (when it is painful to hear)

C in CARE represents:

Counseling, which includes an effort to help clients accept the hearing loss and set reasonable goals.

A in CARE represents

Audibility improvement by using hearing aids and other devices

R in CARE represents

Remediation of communication

E in CARE represents

Environmental coordination and participation goals.

OHCs and cochlea

3 to 5 rows

12,000 cells

50-150 stereocilia

Do not send signals to the brain (efferent)

IHCs in cochlea

1 or 2 rows

3,500 cells

50-70 stereocilia

Send signals to the brain (afferent)

why we use FM systems:

-Radio waves to travel (cros and bicros)

"Two hearing aids on the ears, any sound coming from the side of the dead ear gets transmitted with FM waves to the other hearing aid on the better ear side (still no localization, sounds from both sides will be sent to the side of the good ear)"

-How it (radio waves) travels across the skin

-fm systems are also used in teaching of the deaf, where the teacher wears a microphone that feeds into the hearing aids, goes straight into the hearing aids (where settings can be personalized for each child)

The duration of individual speech sounds in our language covers a range from

about 20 to 400 msec

speech is normally presented around

45 dB HL

Hearing aids have:

noise reduction and know different noises

SNR loss is defined as dB increase in:

signal-to-noise ratio required by a hearing-impaired person to understand speech in noise, compared to someone with normal hearing

For SNR loss the current criterion for children is:

bilaterally profound sensorineural hearing loss is greater than or equal to 90 dB in 12 to 24 month olds. Greater than or equal to 70 dB in 24 month olds to 18 year olds with limited benefit from traditional amplification.

bimodal hearing

when the patient wearings a hearing aid in the ear opposite the cochlear implant can improve localization and improve hearing in noise

For younger children, programming schedule should be:

weekly visits for 2 months, then at 6 months, at 9 months, and every 6 months after that.

Research has indicated that the hearing aid, even in cases with profound hearing

loss:

can provide the patients with prosody information that cannot be provided by current generation implants.

what helps with hearing emotion in speech?

prosody, suprasegmental speech

Patients with a corner audiogram can receive some benefit from a hearing aid in the:

opposite ear to supplement what they are receiving from the cochlear

implant.

-Therefore, a hearing aid trial in the opposite ear is recommended for all patients receiving unilateral cochlear implants.

bilateral implantation will be

$60,000-$80,000 greater than with a unilateral CI

Studies on the cost effectiveness of bilateral cochlear implantation in the pediatric population have found mixed results in that there was an improvement in quality of life with the second implant, but its cost effectiveness was questionable. Surgical risks also increased, there is also the consideration that in the future a device could be developed which can only be implanted in an ear that never had an implant. It is important to consider leaving one ear open for future options.

The decision between bimodal stimulation or bilateral implantation must be made on

an individual basis

Children with bilateral implants could localize better than unilateral users, but

some of the bimodal (using hearing aid) children could perform localization tasks at the same level that the average bilateral user functioned.

If, after a trial period, the patient does not receive any benefit from the bimodal condition compared to the cochlear implant alone condition

a second implant should be considered

Clinics recommend simultaneous bilateral implantation for

infants/young children with profound bilateral HL for best possible hearing for development of speech and language. Others recommend bimodal stimulation so child can hear prosody information.

An auditory brainstem implant (ABI) has been developed for

individuals with neurofibromatosis

who are deafened from bilateral VIII nerve tumors. Implant placed on cochlear nucleus of brainstem,

results with this implant show promise to those who cant benefit from CI's because they lack functioning

VIII nerves.

With electric-acoustic stimulation

the cochlear implant electrode array is placed only in the basal portion of the cochlea and programmed for high-frequency sounds.

Patients have significantly better speech recognition in both quiet and noise with electric-acoustic stimulation, but

in a carefully controlled multicenter study with eighty-seven patients, eight patients lost all of their residual acoustic hearing and seventeen had significant loss of their residual acoustic hearing due to the surgery.

on the audiogram Hl refers to

hearing level

SPL refers to

sound pressure level