Differences in the sensitive phase of the maturation of the

auditory and visual pathwaysDr. Dr. hc. Monika Lehnhardt

Cernobbio, June 2008

„Direct stimulation of the auditory nerves with resultant speech perception is not feasible

M. Lawrence, 1964

“It is a crime to provide deaf children with a cochlear implant”

German physiologist R. Klinke, 1988

From: “Strabismus und Motilität” Zur Entstehung der Amblyopie. Experimentelle Untersuchungen, G.K. v. Noorden Ber. Dtsch. Ophthalmol. Ges. 77, 815 – 828 (1980), P. 821, Abb. 4a

Presbyacusis

pathological, sensorineural

Presbyopie

physiological, mechanical

Charles Eyries, Otologist in Paris

André Djurno, Engineer co-working

with Eyries

Fritz Zöllner Otologist in Freiburg

Wolf Dieter Keidel, Physiologist in Erlangen

Vision for a technology that would enable the deaf to hear

Research supported by public donation, commenced 1967

First cochlear implant, 1978, Melbourne Hospital

“In spite of the problems and criticisms, I just had to go on. A cochlear implant was their only hope of ever hearing.” Professor Graeme Clark

History of the Cochlear Implant

Prof. Dr. Dr. med. dent. hc. Ernst Lehnhardt

The Window of

Opportunity

Sharma et al, 2002

Ear and Hearing, December 2002

Archives of Otolaryngology – Head & Neck Surgery, May 2004

050

100150200250300350400450

0 5 10 15 20 25 30

Age

P1

late

ncy,

ms

Normal limits

14 month old recipient

0

50

100

150

200

250

300

350

0 12 24 36

Age

P1

late

ncy,

ms

Normal limits

13 month old recipient

At CI activation

1 week post CI

1 month post CI

3 months post CI

12 months post CI

Sharma et al, 2004

response to speech sounds

discrimination of speech sounds

use of telephone

Children with normal hearing

Categories of Auditory Performanceref: P Govaerts, C De Beukelaer et al., Neurotology and Audiology 2002 (Antwerp)

Govaerts, et al. 2002

Otology & Neurology, vol 23; 2002

Age at Mainstream Integration

0

20

40

60

80

100

0 3 5 7

Age (in years)

Per

cent

age

of c

hild

ren

Under 2 yrs2 to 4 yrs

Age at implantation

Manuel Manrique, et al (2004)

Laryngoscope, August 2004

Reynell

01234567

0 1 2 3 4 5 6 7

Chronological age (years)

"Rey

nell"

age

(yea

rs)

< 2 yrs

2 to 6 yrs

Average Language Development

0

12

24

36

48

60

72

84

0 12 24 36 48 60 70 84

AGE (months)

Expr

essi

ve L

angu

age

Age

(m

onth

s) 12-24 months25-36 months37-48 months

Svirsky, et al (2004)

Audiology and Neuro-Otology, vol. 9, 2004

Lone Percy-SmithE. Danish CI centre, Gentofte Hospital University of

Copenhagen. October 2007

Factors associated with Speech/Language Outcomes and Social Well-being

for Children with Cochlear Implant in Denmark

N=168. 91 girls. 77 boys.Age 1-18yrs. Mean age if CI = 4 years50 spoken language 85 support sign 30 sign

Lone Percy-Smith continued

Summary – Speech and Language Datatests scored for HA, not CA.• Strong statistical effect of communication mode

at home• Clear improvement of sp./lang. dev. for children

exposed to spoken Danish only• Parent assessments and test responses are highly

positively associated. (auditory capacity and speech intelligibility)

Lone Percy-Smith conclusions

• 64% of CI children had high level of social wellbeing• 36% of CI children with low level - 57% operation age >36 mon - 68% in schools or kindergarten for deaf - 85% use sign support or sign language

Level of social well being significantly associated with communication mode.

Early implantation

Waltzman S & Roland T. 2005 Pediatrics‘Cochlear Implantation in Children Younger than 12 Months’ James A. & Papsin J. 2004 The Laryngoscope‘Cochlear Implant Surgery at 12 Months of Age or Younger’. Colletti V. et al. 2005 The Laryngoscope‘Cochlear Implantation at under 12 Months: Report on 10 Patients.’

Vision

In 20 years, an implant will be the treatment of choice for

anyone with a hearing lossgreater than 50 dB

Dr Jay Rubenstein , March 2004

Thank you for your attention!