Pre-operative evaluation and post-operative rehabilitation for paediatric cochlear implantation

Han Demin, M.D., Ph.D.Beijing Institute of OtolaryngologyBeijing TongRen Hospital Capital University of Medical Sciences

Advances in

Deafness Management2005-10-8-9 Hong Kong

Instruction

The census of China (local) in 2000

– More than 20 million hearing impaired people,

the largest handicapped persons of all the categories.

– Universal Newborn Hearing Screening an incidence of 1 to 3 per thousand live births

800,000 children with hearing impairment

30,000 children per year born with hearing loss

One of the important factors to impact on the quality of life.

Effective early intervention is essential.

Cochlear Implants in mainland of China

There are totally around 2500 cochlear implant recipients since 1996 in mainland of China.

The age of CI recipients has lowered More clinics are conducting surgery and

rehabilitation.

Manufacturers of CI in china

According to the CI Recipients in mainland of China (about 2500 cases)NUCLEUS from AustraliaCLARION from America MED-EL from Austria

995

68 116241

2 21103

22290

0

200

400

600

800

1000

1200M

SP

SPE

CT

RA

SPR

INT

ESP

RIT 3G

TE

MP

O+

CIS

Pro

S-SE

RIE

S

PL

AT

INU

M

BT

E

Distribution of the external

CⅡHifocusSpiral

CI24M

CI22M

CI24R

CI24K

COMBI40+

Distribution of the internal

290

522

443

250

155

0

100

200

300

400

500

600

0-2. 99 3-5. 99 6-11. 99 12-17. 99 18-

Distribution of the age

Essential elements of the process

Surgical technique

Rehabilitation and training

Hearin

g th

e w

orld

Key

Necessity

Periodic mapping

Bridge

Accurate evaluation

Basis

Audiometric assessment system

Psychological and pediatric assessment

Auditory and facial nerve monitoring

Mapping, rehabilitation

Evaluation of hearing aid fitting

Speech audiometry

study for adults and children

Subjective and objective assessment

Researches on Cochlear Implantation

Audiological and Radiological researches

1. Investigation of tone vocalization in Mandarin with CI Recipients

2. Available speech materials and to be standardizing in mandarin and rehabilitation procedures for adults

3. Development of the Lexical Neighborhood Test in Mandarin as a speech test for children

4. Radiological study on the abnormal modality of the cochlea in order to improve surgical skills of cochlear implantation

Researches on Cochlear Implantation

Clinical applications

1. Investigation of audiometric assessment strategies for patients pre- and post- cochlear implantation

2. Setting up the standard of classification for cochlear malformation

3. Establishing indications for selecting teen-age patients who can benefit from cochlear implantation

4. Cochlear Implantation in abnormal cochlea (Mondini, Large vestibular aqueduct syndrome, etc.)

Pre-operative evaluation

• Comprehensive audiological evaluation

• Other tests :

• language, psychological, mental tests

• radiological tests (CT & MRI)

• learning ability tests

Comprehensive audiological evaluation

Subjective hearing test （ behavioral test ) Impedance test ABR Auditory steady-state response (ASSR) OAEs Speech audiometry Hearing aid fitting

Behavioral test

Behavioral observation audiometry (BOA): under 6 month

Visual reinforcement audiometry (VRA): 6 to 24 months

Play audiometry (PA) : 2 to 6 years old

Also be used to get the threshold for speech reception

Not widely used in China and this limits the appropriate

candidate selection for cochlear implants

Impedance test

Testing the status of the middle ear Rule out conductive hearing losses.

ABR

• ABR (click induced) can only give thresholds at

middle to high frequencies (2000 ～ 4000 Hz)

without an accurate estimation of low frequency

hearing threshold

• Tone-burst stimulation can be used to obtain

thresholds for each frequency, but takes a long time

Auditory steady-state response (ASSR)

Used for children at different ages Main advantage: frequency specificity Each clinic should establish its own

normalization data before interpreting the results

OAEs

OAE is used to evaluate the function of the cochlea, especially the outer hair cells

OAE is not ease to define the degree of the hearing loss

Speech audiometry

Available speech materials in mandarin– for adults: the minimal auditory capabilities

(MAC)– for children: pediatric speech perception test

We are going to standardizing the mandarin materials

Hearing aid fitting

Pre-operation Binaurally hearing aid fitting 3-6 months auditory training Aided audiogram, and speech perception testing

at the start and end of the trial Compare the results with current average CI res

ults

Current situation of post-operative rehabilitation

Rehabilitation Service Rehabilitation and training model Rehabilitation and training approach Factors affecting outcome Psychological education for cochlear implant recipients and

parents

Government organizations Private organizations Home based Special schools Hospitals or welfare organizations

Rehabilitation Service

Rehabilitation and training model

Class model Class plus parents Individual rehabilitation Individual plus parents Individual combing with integrated class mode Intensive training combing with integrated class

Rehabilitation and training approach

Auditory verbal training Real scenario verbal training

Factors affecting outcome (1)

Auditory detection frequency range Normal delivery at birth is better than at risk factors Infants with normal motor skills are better Onset of hearing loss, late onset is better than

congenital Duration of hearing loss, shorter is better More residual hearing is better

Factors affecting outcome (2)

Intervention pre-operatively: Early binaural intervention with full frequency range is better

Rehabilitation and education history: intensive Age Degree of speech disorder Family and language environment Expectation of parents and recipients

Psychological education for CI recipients and parents

Communication between the rehabilitation organizations and the parents

Improve teachers’ ability to provide counseling Make friends with the recipients Create an environment for emotional rehabilitation Back to mainstream