DEMAND and CAPACITY OF COCHLEAR IMPLANTATIONS

RUUD van HARDEVELD

Content

1. European situation

2. Intermediate conclusions

3. Study on demand and necessary capacity

4. Conclusions

Total implantations up to 2008

0

2000

4000

6000

8000

10000

12000adults

children

All-users

CI-wearers per million inhabitants ultimo 2007

0

20

40

60

80

100

120

140

160

180

200

N(total)

Adults

Children

Implantation Capacity per Million in 2007

0

5

10

15

20

25

30

Bilaterally implanted Children

• Spain 228

• Sweden 218

• Italy 126

• Netherlands 67

• Belgium 42

• Turkey 4

• Luxembourg 4

CUMULATIVE NUMBER CI's per MILLION INHABITANTSNetherlands

0

20

40

60

80

100

120

140

160

2005 2006 2007

KIDS

ADULTS

TOTAL

NUMBER of CI's per yearNetherlands

0

50

100

150

200

250

300

350

400

450

2005 2006 2007

KIDS CI's

ADULTS CI's

TOTAL NUMBER

CI's per million inhabitantsNetherlands

0

5

10

15

20

25

30

2005 2006 2007

KIDS

ADULTS

TOTAL CI'S

Conclusions on state of art

1. Number of implantations/million inhabitants varies greatly

2. Rich countries (Ch, S) show a cumulative number of 180 implantations whereas less strong economies show about 40

3. The maximum implantation capacity is presently in between 20 and 25 per million

4. The less strong economies spent their short money on children

5. Bilateral implantation is still exceptional

AIM OF THE STUDY

• DETERMINE THE NUMBER OF POTENTIAL CI – CANDIDATES( THE EXISTING RESERVOIR)

• DETERMINE THE YEARLY FLUX into RESERVOIR- OF HOH- OF SUDDENLY DEAFENED ADULTS/ CHILDREN- OF NEONATES ( BORN DEAF OR PROFOUNDLY DEAF)

• COMPARE CAPACITY with POSSIBLE DEMAND NECESSARY VERSUS AVAILABLE,

RESERVOIR

BORN DEAF

CI-DEMANDPASSING TRESHOLD

DEAFENED ADULTS / CHILDREN

FLOW DIAGRAM

RESERVOIR

??????

BORN DEAF 200-240

TO CI400

PASSING TRESHOLD ?????

60-80

DEAFENED ADULTS / CHILDREN 200

70 - 100

FLOW DIAGRAM

THRESHOLD FOR CI

• HEARING LOSS > 90 dB on BETTER EAR

• SPEECH INTELLIGIBITY score < 30 - 40 %

• Additional criteria in personal performance sphere

CHALLENGING QUESTIONS:

How to estimate the number of

- HOH passing THRESHOLD ?

- Content of the RESERVOIR ?

COMBINE

- DATA on PREVALENCE of HOHA.DAVIS, Hearing in Adults,

London, 1995assuming:Data unchanged todayValid in Industrialized EU-countries

- DEMOGRAFIC DATA of CBS

Cumulative POPULATION ( MILLIONS )

AGE 1994 2004 2010

< 20 3,751 3,987 4,009

< 40 8,762 8,535 8,83

< 65 13,333 14,006 14,180

< 80 14,877 15,699 16,05

< 100 15,341 16,257 16,667

40-100 6,58 7,72 7,84

Prevalence in age group 18-80 years

-1,0

-0,5

0,0

0,5

1,0

1,5

2,0

2,5

0 10 20 30 40 50 60 70 80 90 100

Hearing Loss > X dB

log

arit

hm

(p

reva

len

ce %

)

SLOPE of PREVALENCE (P) versus HEARING LOSS in dB

• Log P(x) = 2 – 0,0278 x x = dB HL• P (x) = 100*10(exp -0,0278x)• P ( x + 10 ) = 0, 527 . P ( x )

• This formula says : The prevalence of HL at a certain level

decreases by a factor 1 / 0,527 = 1,9 if the HL increases 10 dB

-1,5

-1,0

-0,5

0,0

0,5

1,0

1,5

2,0

2,5

0 10 20 30 40 50 60 70 80 90 100

HL > x dB

Lo

ga

rith

m o

f p

rev

ale

nc

e %

age group 18 - 30

age group 31 - 40

age group 41 - 50

age group 51 - 60

age group 61 - 70

age group 71 - 80

overall

PREVALENCE per AGE GROUP

-1,5

-1,0

-0,5

0,0

0,5

1,0

1,5

2,0

2,5

0 10 20 30 40 50 60 70 80 90 100

HL > x dB

Loga

rithm

of p

reva

lenc

e %

age group 18 - 30

age group 31 - 40

age group 41 - 50

age group 51 - 60

age group 61 - 70

age group 71 - 80

overall

Prevalence versus Age

-1

-0,5

0

0,5

1

0 2 4 6

AGE CLASS

LO

G P

RE

VA

LE

NC

E

> 80 dB

> 90 dB

INCREASE OF PREVALENCE PER 10 YEARS of AGE

The slope of the line

LOG P(x + 10) = LOG P (x) + 0,367

P(x + 10) / P (x) = 2,3

Prevalence increases 2,3 fold every 10 years

Number of CI-CANDIDATES from log-plot

Overall in 2004

Population (18 – 100 years) = 12.700.000

> 80 dB > 90 dB

Prevalence 0,569 % 0,265 %

N (18 – 100) 72.263 33.655

Prevalence from the Differential log-plots

Σ = sum [ N(x - (x + 10)) * P(x - (x + 10)) ] x = 41, 51, 61, 71, 81, 91

HL > 80 dB > 90 dB

1994 59.873 30.394

2004 70.347 (72.263) 35.713 (33.655)

25 - 35%17.600- 24.600 8.900 (12.500)

FLUX N (>90 dB) 1th order approximation

1994 N(30-100) = 9.140.000 =>

2004 N(40-100) = 7.100.000

Survival ratio (migration included) = 0,84

2004 42.591

2005 33.869 x 0,84 = 28.450

10 years difference 14.141

FLUX / YEAR at > 90 dB1.414

RESERVOIR

35.713

BORN DEAF 200-24033 %

TO CI400

PASSING TRESHOLD60-80

DEAFENED 200ADULTS / CHILDREN 35 – 50 %

70 - 100

1.414 350 - 49025 – 30 %

FLOW DIAGRAM at > 90 dB

RESERVOIR

2000

BORN DEAF 12,5 - 1533 %

TO CI25

“40”

4 - 5

DEAFENED 12,5

ADULTS / CHILDREN 35 – 50 %

4 – 6,5

PASS THRESHOLD

90 22 - 2725 – 30 %

FLOW DIAGRAM at > 90 dBper MILLION INHABITANTS

Birth rate per 1000 inhabitants

• Austria 8.7 L’bourg 11.8

• Belgium 10.3 Netherlands 10.7• Denmark 10.9 Norway 11.3• Estland 10.2 Spain 10.0• Finland 10.4 Sweden 10.2• France 12.9 Swiss 9.7• Germany 8.2 Turkey 16.4• Greece 9.6• Italy 8.5 www.census.gov/ipc

Implantations per Million in 2007

0

5

10

15

20

25

30

Conclusions at > 90 dB

• A LARGE RESERVOIR of CI-POTENTIALS EXISTS (about 35.713)

GO-NO GO ratio unknown

• YEARLY FLUX to the RESERVOIR

1.414 PROGRESSIVELY DEAFENED200 – 240 NEONATES200 SUDDENLY DEAFENED

GO - NO GO ratio 35 %

• IMPLANTATION CAPACITY FAR BEHIND DEMAND