New Cochlear Implant Criteria

Making a NICE change

Deborah VickersUniversity of Cambridge, Clinical Neurosciences

Padraig KitterickNottingham Biomedical Research Centre

Tracey TwomeyChair of British Cochlear Implant Group

▪ Help clinicians to implement evidence-based medicine

Ensure that individuals receive the devices that are likely to provide the most benefit

Avoid unnecessary surgery

▪ Ensure that resources are used efficiently

▪ Equal access across geographical areas

▪ Necessity in publicly funded system for allocation of resource

Why do we need explicit candidacy criterion?

We therefore have to draw a line in the sand

Who are NICE

The National Institute for Health and Care Excellence (NICE)

was set up in 1999 to reduce variation in the availability and

quality of National Health Service (NHS) treatments and care. It

is accountable to the UK Department of Health, but operates

independently of government.

They provide national guidance and advice to improve health

and social care

Adults and children with bilateral profound deafness who receive insufficient benefit from hearing aids.

▪ PTA >90 dB HL at 2 & 4 kHz bilaterally

Insufficient benefit from hearing aids considered as :

▪ Children: speech, language and listening skills inappropriate for age, developmental stage and cognitive ability

▪ Adults: a score of <50% on Bamford–Kowal–Bench (BKB) sentence testing at a sound intensity of 70 dB SPL

Unilateral implantation for adults (unless significant additional sensory impairment) and bilateral implantation for children.

UK criteria – established in 2009

Criteria heavily based on UK Cochlear Implant Study Group work

▪ Data only on adults received implants between 1988 and 2000

▪ Adults had very poor hearing (PTA = 115 dB HL in better ear!)

▪ No data from children

Patients implanted after NICE guidance likely to have:

▪ Better hearing function (speech perception)

▪ Larger and healthier population of spiral ganglion cells

▪ Greater access to hearing in non-implanted ear

Where did the UK candidacy criteria come from?

UKCISG (2004) Ear Hear, 25, 310-335;

Cochlear implant candidates are changing

Mean scores at

both 3 and 9-12

months higher

than 55%

Greater residual

hearing

Shorter duration of

deafness

Post-operative

mean in 2009

Use contralateral

hearing aids or

Electro-acoustic

stimulation (EAS)

In 2015 members of British Cochlear Implant Group (BCIG)

said that candidacy issues are the most important

factor that BCIG council should work on

Candidacy working group set up to compile evidence

Research design

28 children with bilateral cochlear

implants

Severe to profound hearing

impairment

Assessment one

Children aged 3 to 6 years

Assessment two

Children aged 4 to 7 years

Evidence from children

43 children with bilateral hearing

aids

Mild to profound hearing

impairment

Lovett, Vickers, Summerfield (2015) Ear Hear

• CAPT monosyllables in quiet

• McCormick word test in noise

• McCormick in babble

Outcome measures

Summary

Outcome measure Two-frequency audiogram

Speech perception in

quiet

79-83

Speech perception in

noise

88-92

Speech perception in

babble

78-80

Unaided two-frequency audiogram ≥ 80 dB HL bilaterally

Lovett, Vickers, Summerfield (2015) Ear & Hearing

Outcome measures

Evidence that current criteria are too restrictive

http://www.tandfonline.com/toc/ycii20/17/sup1

▪ Need to consider fitting hearing aids for contralateral ear

▪ Candidacy needs to be appropriate for Electroacoustic stimulation candidates

▪ With improved techniques for preserving hearing, this is a critical area of consideration

▪ Assymetric losses

▪ Ear-by-ear candidacy

Fielden, 2016; Kitterick and Lucas 2016; Sadadcharam, 2016; Verschuur, 2016; Wilson, 2016;

Findings from supplement: Residual hearing

Questionnaire covering four areas

1. Methods of funding for unilateral and bilateral implants;

2. The presence or absence of specific guidelines, or criteria,

▪ pure tone audiometry (PTA);

▪ speech perception tests (in quiet or in noise);

▪ Individual characteristics such as duration of deafness; onset of deafness; age; aetiology; other disabilities;

3. Specific factors that can exclude implantation;

4. Whether there is flexibility within the system

Responses

28 respondents, representing 17 countries:

Argentina, Australia,

Belgium, Bosnia Herzegovina, Brazil,

Finland,

Germany,

India, Italy,

The Netherlands, New Zealand,

Portugal,

South Africa, Spain, Switzerland,

United Kingdom, and The United States of America.

▪ 80% of countries have audiometric criteria for paediatrics

▪ 70% of countries have audiometric guidelines for adults

▪ A range audiometric criteria (bilaterally):

▪ Australia - mean thresholds > 70 dB HL above 1.5 kHz

▪ Belgium - mean thresholds > 85 dB HL at .5, 1.0, and 2.0 kHz

▪ UK – thresholds > 90 dB HL at both 2 and 4 kHz

▪ Typical pattern - mean thresholds > 75–80 dB HL above 1 kHz

Audiometry

Words41%

Sentences24%

Both35%

Words

Sentences

Both

Speech testing

85% countries

have speech-

based criteria

Words allow for

assessing access

to sounds

Individual feedback

Group discussion

32 candidacy

statements

derived from survey

Round 2

(interactive voting)

11 additional candidacy

statements

derived from discussion

Round 1

(by questionnaire)

Voting on Candidacy statements

Candidacy consensus 2017

Considered

agreement /

disagreement

for a score of

80%

Expanding candidacy to include individuals with less profound forms of hearing loss would be appropriate because benefits outweigh risks

Current assessment to determine sufficient benefit from hearing aids (the BKB sentence test) does not adequately assess listening difficulties

Process to determine whether someone receives sufficient benefit from hearing aids should be revised to better assess real-world listening

Assessment procedures should be based on evidence that they are reliable and valid for determining candidacy for cochlear implantation

Results

https://cicandidacy.co.uk/

Candidacy consensus

Respondents reviewed clinical scenarios (600) to determine

if appropriate for implantation and also if necessary

• Appropriate (benefits outweigh any harms)

• Necessary (improper care not to provide implantation)

≥ 70 dB HL ≥ 80 dB HL > 90 dB HL

Type of scenarios captured by criteria:

Appropriate

and necessary

96%

Appropriate but

unnecessary

4%

Inappropriate 0%

https://www.cicandidacy.co.uk/

Appropriateness analysis

Respondents reviewed clinical scenarios (600) to determine

if appropriate for implantation and also if necessary

• Appropriate (benefits outweigh any harms)

• Necessary (improper care not to provide implantation)

≥ 70 dB HL ≥ 80 dB HL > 90 dB HL

Type of scenarios captured by criteria:

Appropriate

and necessary

97% 96%

Appropriate but

unnecessary

3% 4%

Inappropriate 0% 0%

https://www.cicandidacy.co.uk/

Appropriateness analysis

Respondents reviewed clinical scenarios (600) to determine

if appropriate for implantation and also if necessary

• Appropriate (benefits outweigh any harms)

• Necessary (improper care not to provide implantation)

≥ 70 dB HL ≥ 80 dB HL > 90 dB HL

Type of scenarios captured by criteria:

Appropriate

and necessary

76% 97% 96%

Appropriate but

unnecessary

12% 3% 4%

Inappropriate 12% 0% 0%

https://www.cicandidacy.co.uk/

▪ Crucial speech frequencies between 750-3000 Hz

▪ Transmit vowel formants

▪ Slightly lower for sentences and running speech

▪ Word tests better at assessing spectral aspects of speech

▪ Low frequency dead regions have devastating impact on speech understanding

▪ Individuals with unusual configurations of loss should be accommodated

Will a cochlear implant help to better hear

speech sounds?

▪ BCIG central data collection with 10 UK centres

▪ Assessments in adult CI users at:

▪ pre-implant,

▪ 3 months post switch on

▪ 9-12 months post switch on

▪ Collecting:

▪ Word scores (ABs); scored by word and phoneme

▪ BKB sentences; scored by key word correct

UK adult speech test evaluation for candidacy

▪ Strong relationship between BKB sentences and AB scores (both

word and phoneme)

▪ A BKB score of 50% is equivalent to an AB word score of 19%

and an AB phoneme score of 35%

▪ A BKB score of 70% is equivalent to an AB word score of 27%

and AB phoneme score of 50%

UK adult speech test evaluation for candidacy

Previous criteria

Suggested change

Recommendations to NICE (2018)

Amend hearing threshold criteria to ≥80dBHL at two or more

frequencies from 500Hz, 1000Hz, 2000Hz, 3000Hz and

4000Hz bilaterally without acoustic hearing aids.

Amend speech criteria for adults to a phoneme score of <50%

on the monosyllabic word test Arthur Boothroyd (AB)

For children, speech, language and listening skills less than

expected for age and cognitive ability judged clinically

For all candidates, the multidisciplinary clinical team should consider whether CIs provide benefit beyond hearing aids.

March 7th 2019 NICE launched a

new version of the guidance on

cochlear implants

https://www.nice.org.uk/guidance/ta566

Summary on implant candidacy▪ Success because we took a coordinated approach

▪ Stakeholders from charities, industry, clinics, universities and patient groups worked together

▪ Worldwide trend to update and relax candidacy

▪ UK is extremely conservative

Evolving candidacy

▪ Population is evolving

▪ We need flexibility to meet all patient’s needs

▪ Ideally ongoing data monitoring

Thank youdav1000@cam.ac.uk