Implications of Auditory Neuropathy for EHDI Programs Vickie Thomson MA Sandra Gabbard, PhD Arlene Stredler Brown, MA Marion Downs Hearing Center Denver, CO

Faculty Disclosure Information In the past 12 months, I have not had a significant financial interest or other relationship with the manufacturer(s) of the product(s) or provider(s) of the service(s) that will be discussed in my presentation. This presentation will (not) include discussion of pharmaceuticals or devices that have not been approved by the FDA or if you will be discussing unapproved or "off-label" uses of pharmaceuticals or devices.

Contributing Researchers Yvonne Sininger, Ph.D. Arnold Starr, M.D. Linda Hood, Ph.D. Charles Berlin, Ph.D. Lazlo Stein, Ph.D. Jon Shallop, Ph.D. Gary Rance, MSc.

Auditory Neuropathy vs Auditory Dys-synchrony Berlin, Hood and Rose coined the term dys-synchrony to provide a more comprehensive view of auditory neuropathy The auditory nerve may not be affected AN may lend towards not considering cochlear implants as an option

What is AN/AD? Abnormal auditory brainstem responses Normal otoacoustic emissions Normal outer hair cell function Abnormal neural function No acoustic reflexes Large cochlear microphonic

What is AN/AD? Speech perception worse than expected based on the audiogram Inconsistent responses to sound Worse in noise Fluctuating hearing loss If a maturational problem recovery may return by months Perceptual ability may improve although ABR remains abnormal.

Variability Progressive loss of peripheral auditory function (e.g. loss of OAEs, CM) Stable Worsen Partial recovery

Historical Perspective 1980s first published accounts of normal hearing and absent ABRs Davis and Hirsh, Worthington and Peters 1984 Kraus et.al reported 1.3% of the children with hearing loss had absent ABRs Addition of OAE increased the diagnostic capabilities

Incidence? Davis and Hirsh –.5% Berlin – 12% Kraus – 1.3% Rance % of the severe to profound

NICU vs. Well Baby Rance reported that 85% were NICU graduates Berg et al reported 24% of a NICU cohort had AN/AD profiles (23% were bilateral) 39% > 38 weeks gestation Colorado study

Colorado Screening Rates Year# of Births # Screened # Referred Confirmed hearing loss (97%) 2997/4.5% (97%) 2368/3.3% 143

Methods Data from both the Colorado Department of Public Health and Environment and the Colorado Home Intervention Program was analyzed. All hearing losses were identified by local audiologists and reported to these agencies

Increasing Identification Rate for AN/AD

AN/AD Incidence Combined (2003&2004) Cases Identified 8917 Total Screened 67,77866, ,345 Incidence rate 1.18:10, :10, :10,000

Hispanic Incidence Rates Combined (2003&2004) Cases Identified 336 Total Screened 21,53321,58243,115 Incidence rate 1.39:10,000

Age of Identification

Risk Factors 15 of 20 (75%) bilateral AN/AD cases were admitted to the NICU 7 of 20 (35%) bilateral AN/AD cases were premature births

Associated Risk Factors Anoxia Hyperbilirubinemia Infectious diseases (e.g. mumps) Immune disorders (e.g. Guillain-Barre syndrome) Genetic Syndromes (e.g. Charcot-Marie- Tooth and Fredreichs Ataxia) Hereditary recessive and dominate

Recommendations for Screening Use AABR in the NICU Recognize that AN/AD is present in well baby infants Educate medical homes about the importance for referring whenever there is a concern regardless of the screening outcome

RECOMMENDED PROTOCOL FOR INFANT AUDIOLOGIC ASSESSMENT THE COLORADO INFANT AUDIOLOGIC ASSESSMENT TASK FORCE

AUDIOLOGIC DIAGNOSTIC ASSESSMENT ABR Otoscopic Acoustic immittance (high frequency probe) TEOAE &/or DPOAE BOA

ABR Assessment Threshold search to clicks in 10 dB steps If NR, compare rarefaction & condensation click response (auditory neuropathy) Threshold search to 500 & 3000 Hz tone pip (or ASSR) Threshold search to clicks by bone conduction

Issues in Infant ABR Assessment Always look for cochlear microphonic when neural response is abnormal or absent (Auditory Neuropathy) Must have frequency specific thresholds (tones or ASSR) Bone Conduction may be useful Placement of oscillator Calibration Head band versus hand held position

ASSR and Behavioral Thresholds In general, ASSR thresholds are within 20 dB of behavioral thresholds Largest discrepancies when hearing is normal Best correlated for severe to profound hearing losses Differences greatest in the low frequencies Aoyagi et al, 1994, Levi et al, 1995, Rance et al, 1995, Lins et al, 1996, Picton et al, 1998

Otoacoustic Emissions Sound produced by Outer Hair Cell movement in response to a stimulus Evoked Emissions Distortion Product (DPOAE) Transient Evoked (TEOAE) Spontaneous (SOAE) Present for hearing better than approximately 35 dB with normal middle ear function.

Why Behavioral Testing? Behavioral tests are the only true tests of hearing (Sininger, 1993 cited in Hicks,Tharpe & Ashmead, 2000 ) permits observation of the infants auditory development demonstrates auditory behaviors to parents and caregivers

Why Behavioral Testing? Behavioral tests serve as cross- checks of physiologic measures (Jerger & Hayes, 1976) confirms audiometric configuration (OAE; ABR) determines presence of conductive component (ABR; immittance measures) confirms threshold predictions (ABR)

Recommendation for Behavioral Assessment Use age appropriate techniques and use child's developmental level. Use insert phones when possible. Use audiologist in room with child. Use quiet distracting toys. Use multiple reinforces to keep attention. Use a variety of interesting stimuli. Always include as part of test battery!!!

Recommendations for Middle Ear Assessment Do not rely of 226-Hz tympanometry in infant under 6 months of age. Between 4-6 months, it appears that 226-Hz tympanograms begin to be effective for detection of MEE. For ages birth to 6 months, use a higher probe frequency ( Hz), with criteria of any discernable peak within normal range. Correlate results with other diagnostic measures.

Medical testing Genetic testing Ophthalmologic evaluation by 12 months of age CMV titers- test ASAP after birth FTA-ABS EKG (Jervell and Lange-Neilson Syndrome) CT/MRI Cochlear dysplasia/large vestibular aqueduct syndrome Cochlear ossification following meningitis

Developing a Treatment Program for Children with Auditory Neuropathy Arlene Stredler Brown, CCC-SLP, CED

What do we know? Diagnosis is difficult for parents to understand Course of the condition is unpredictable The greatest need is to monitor language development and auditory development in order to develop an appropriate treatment plan

What is difficult for parents? Feeling helpless Waiting to reach a definitive diagnosis Variability in skills among children Identifying a communication method Finding comfort in making choices that may change

Developing an Action Plan.. Helping parents during the diagnostic process Specific audiologic battery Helping parents to locate treatment Information, support, navigating the Part C system, the EHDI system, and other early childhood initiatives

Developing an Action Plan.. Developing a unique intervention program Identify the functional profile of the child Assessment in a variety of developmental domains Communication Language Functional auditory skills Speech Cognition

Developing an Action Plan.. Assess at regular intervals to monitor achievement Baserate data Rate of progress Maintain development commensurate with cognitive age

Trends in Successful Treatment Visual communication Speechreading English-based signs Cued Speech (receptive vs. expressive) Cochlear Implants

Cautions in Treatment Methods Amplification (according to some) American Sign Language (ASL) Auditory-Verbal therapy

Creating a Profile of Functional Auditory Skill Development Expect auditory behaviors that are not hierarchical Monitor for changes in auditory behavior (may become more systematic) Document listening in a variety of conditions Quality of responses to auditory stimuli Identify conditions when the child responds Identify consistency of responses Look for variability Aided vs. unaided

Auditory Skill Development Monitor with trial amplification Awareness vs. speech discrimination Parents desire to be pro-active Caution regarding power of amplification With a cochlear implant, expect hierarchical auditory skill development Allow time for spontaneous recovery Monitor development of speech & language Identify auditory discrimination skills vs. pure tone hearing levels Determine site of lesion

Tools to Measure Functional Auditory Skill Development Functional Auditory Performance Indicators (FAPI) – Stredler-Brown & Johnson Auditory-Verbal Ages & Stages of Development - Estabrooks The Developmental Approach to Successful Listening II (DASL) – Stout & Windle The Development of Listening Function - Razack

Creating a Functional Developmental Profile Assess at regular intervals IFSP recommends every six months Expect developmental gains at a rate that is commensurate with that child s cognitive skills

Creating a Functional Developmental Profile Types of assessment Parent/caregiver report direct observation of the child Observation of child s interaction with a parent videotaped interaction Clinician-administered assessments Multi-disciplinary – all developmental domains

Developmental Domains to Assess Cognitive skills Functional Auditory Skills Communication Skills Gesture communication intention facial expression turn-taking Vocalizations

Developmental Domains to Assess Language Skills (receptive & expressive) Language areas Semantics Syntax Pragmatics Skill areas: Imitation Initiation of communication Production of sounds, words, sentences Modalities Visual: Speechreading, sign language Auditory Multiple modes

Developmental Domains to Assess Speech Development number of utterances quality of utterances Spontaneous condition Spontaneous imitation Prompted imitation inventory of specific phonemes Vowels Consonants Non-true words and true words Speech intelligibility for true words Subjective Objective (e.g., LIPP)

Considerations When Choosing a Method Options Purpose/goals Develop language Develop language Develop English Develop English Potential to develop speech Potential to develop speech Evaluate what is available in the schools Do not limit choice based on availability Do not limit choice based on availability Prepare local school district to offer instruction using the method you have chosen Prepare local school district to offer instruction using the method you have chosen

A TEAM EFFORT… It is to be hoped that, in the future, intervention and education for children with auditory neuropathy will be more prescriptive. At this time, however, professionals have the responsibility to work as a team, to identify the developmental profile of each child in an effort to identify appropriate intervention strategies. And, as professionals, we have a responsibility to remain committed to the method or methodology that works for each child.

Identifying the Team Audiologist diagnosing the condition monitoring the course of the condition monitoring the use of amplification recommending candidacy for a cochlear implant ENT/Otologist Early Interventionist: Educator of the D/HH, SLP, Educational Audiologist Experienced parents Other physicians

Qualities to look for in an Interventionist/Therapist Skilled in a variety of modes/communication methods supports options knows parent-centered intervention paradigm knowledgeable about auditory training techniques knows specific visual communication techniques; advantages & challenges Cued Speech Cued Speech Sign language/s: MCE, CASE, PSE, ASL Sign language/s: MCE, CASE, PSE, ASL Speechreading Speechreading

Final Note! Reminder…. Do not change method randomly – even after CI