* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Types
Survey
Document related concepts
Sound localization wikipedia , lookup
Speech perception wikipedia , lookup
Specific language impairment wikipedia , lookup
Auditory processing disorder wikipedia , lookup
Telecommunications relay service wikipedia , lookup
Olivocochlear system wikipedia , lookup
Evolution of mammalian auditory ossicles wikipedia , lookup
Auditory system wikipedia , lookup
Hearing aid wikipedia , lookup
Hearing loss wikipedia , lookup
Noise-induced hearing loss wikipedia , lookup
Sensorineural hearing loss wikipedia , lookup
Audiology and hearing health professionals in developed and developing countries wikipedia , lookup
Transcript
Early Hearing Detection and Intervention – The Role of the Primary Care Physician AAP CME Teleconference, Part I October 15, 2003 Types of Congenital/Early Onset Hearing Loss and Why It Is Important to Know the Difference Gravel Hearing Loss Characterized broadly by degree, configuration and type, – Degree: amount of hearing loss in relationship to normal auditory function – Configuration: overall ‘shape’ or pattern of the hearing loss as displayed on the conventional audiogram in dB HL as a function of frequency – Type: site (location) of the auditory disorder Degree: Categories of HL • • • • • • • Normal Borderline (Minimal) Mild Moderate Moderate-severe Severe Profound • • • • • • • -10 to 15 dB HL 16 to 25 dB HL 26 to 40 dB HL 41 to 55 dB HL 56 to 70 dB HL 71 to 90 dB HL > 90 dB HL New York State Department of Health Hearing Loss Characterized broadly by degree, configuration and type, – Degree: amount of hearing loss in relationship to normal auditory function – Configuration: overall ‘shape’ or pattern of the hearing loss as displayed on the conventional audiogram in dB HL as a function of frequency – Type: site (location) of the auditory disorder Configuration: Sloping High frequency thresholds >20 dB poorer than low frequency Frequency in Hz Hearing Level (HL) in dB .25k Stach, 1998 -10 0 10 20 30 40 50 60 70 80 90 100 110 .5k 1k 2k 4k 8k Hearing Loss Characterized broadly by degree, configuration and type, – Degree: amount of hearing loss in relationship to normal auditory function – Configuration: overall ‘shape’ or pattern of the hearing loss as displayed on the conventional audiogram in dB HL as a function of frequency – Type: site (location) of the auditory disorder Types of Hearing Loss: Conductive • Reduction of air-conductive sound delivered to the normal cochlea during transmission through a disordered outer ear and/or middle ear • Sound reaching cochlea attenuated to some degree (in OME or debris ~25 dB HL; in complete atresia, maximally ~60 dB HL) • Excellent speech perception when incoming acoustic signal is sufficiently intense Type of Hearing Loss: Sensory • Damage to outer or outer and inner hair cells of the cochlea • Differing impact on speech perception depending on degree and configuration of hearing loss • Multiple audiometric configurations • Any degree of hearing loss Types of Hearing Loss: Mixed • Both sensory component and overlying conductive component • Example: child with sensory loss who experiences OME Types of Auditory Disorders: • Neural – Outer ear, middle ear and cochlea (OHCs) intact – Deficit in neural transmission (auditory neuropathy) • Central – Conductive, sensory & neural pathway intact – Processing deficit at higher levels of the central nervous system Hearing Loss: Characterized by Ear(s) Affected • Bilateral • Unilateral (in one ear only) What are the major genetic and environmental causes of congenital hearing loss ? Vohr Characteristics of Children with Hearing Loss Site Rate Well Baby Nursery 1 per 1000 NICU 10 per 1000 Total population 2-3 per 1000 # infants ident annually US 8,000-16,000 Average career pediatrician 12 patients JCIH Risk Factors for Infants birth to 28 days • Any illness requiring admission to the NICU for > 48 hours. • Stigmata associated with a syndrome known to include SNHL or conductive HL • Craniofacial anomalies including the pinna and ear canal • In utero infections including CMV, herpes, toxoplasmosis and rubella • Family history of permanent HL Most Common Specific Environmental Risk Causes CMV > 1 risk factor Meningitis Perinatal Asphyxia Prematurity < 1500 g Ototoxic medications Some Infants pass their hearing screen and have late onset hearing loss Some of these infants have a risk factor and some have no risk factor known to the family or physician. Risk indicators from 29 d to 2 years of age • • • • • • • Stigmata or Syndrome associated with HL In-utero infections Postnatal infections Neonatal indicators such as ECMO Neurodegenerative disorders Head trauma Recurrent or persistent OM Risk Indicators obtained from the family • Parent or caregiver concern regarding hearing, speech, language, or developmental delay (parent concern has been shown to be a good predictor). • Family history of permanent HL in first or second degree relatives with onset by 30y or age. Causes of Permanent Hearing Loss in 100 Infants 50% Environmental 50% Genetic 50 30% syndromes (>300) 30 20% >75 genes ident 20 ½ are GJB2 – Connexin 26 Genetic Causes Single gene Connexin 26 Gene + environment Mitochondrial + ototoxic Gene + gene Gene + other gene The Connexin 26 Gene • It is estimated that 50-80 % of all autosomal recessive congenital deafness may to due to mutations in th3e Cx-26 gene on chromosome 13q11-q12 • The Cx gene produces a gap junction protein expressed between the outer hair cells and supporting cells and is involved with auditory transduction. • The estimated carrier frequency in the general population is 1 in 31. (Estivill et al, 1998) Genetic Testing • Obtaining an adequate sample for DNA testing is now quite easy • Bilateral buccal smears with a Q tip provide adequate genetic material for testing. • The follow-up genetic counseling is key to the success of genetic testing. New technologies used in hearing screening Gravel Otoacoustic Emissions (OAE) • By-product of the active processing of healthy OHC • Recording of an OAE – Indicates healthy OHCs (cochlea) – Presence highly correlated with normal hearing sensitivity or no greater than a mild hearing loss • Sensorineural hearing losses of greater than about 30 dB HL generally result in absent OAE. • Since recording OAE requires normal forward and backward transmission of energy to and from the cochlea, conductive hearing loss associated with middle or outer ear abnormality can result in absent OAE Types of OAE • Spontaneous OAEs • Evoked OAEs – Transient OAE (TEOAE, TOAE, or click-OAE: COAE) – Distortion Product (DPOAE) TEOAE • Elicited by transients or brief stimuli – Clicks: rapid onset, broadband stimulus containing energy from low through high frequencies (i.e., across speech frequency range) – Tone bursts: more frequency-specific Distortion-Product OAE (DPOAE) • Occur as a result of nonlinear processes of the cochlea • When 2 tones are presented to the cochlea, “distortion” occurs in the form of other tones (harmonics) that are not present in the 2 eliciting tones Screening Technologies - Neonates Evoked Otoacoustic Emissions EOAE Advantages: • Quick • Inexpensive • Frequency-specific • Identifies cochlear and conductive losses: mildmod? • Pass-refer screening devices available EOAE Disadvantages: • Sensitive to ear canal and middle ear conditions • Sensitive to noise (internal & external) • Cannot identify neural disorders including auditory neuropathy • High fail rates in some programs. Device Options for OAE Screening Types • Handheld • Portable screening devices • PC-based hybrids • PC-based clinical systems Auditory Brainstem Response (ABR) • Recording (through surface electrodes) of the micro-volt electrical activity generated by the cochlea and transmitted by the auditory nerve and brainstem pathways in response to brief clicks. • Clicks produce a synchronized response from neural fibers; a tracing of the response is a series of waves Screening Technologies – Neonates Screening (Automated) Auditory Brainstem Response (SABR or AABR) ABR Advantages: ABR Disadvantages: • Identifies cochlear, • conductive and neural • losses: ? mild-mod. • Pass-refer screening • devices. Some test both ears simultaneously. • • Relatively insensitive to transient ear canal, middle ear & external noise. • • ? Lower fail rate than OAE Test time Disposable costs Infant state/myogenic artifact Requires electrode prep, placement & removal Click can miss unusual configurations of HL Examples of screening ABR technology In-Hospital Screening: Two Technology Protocol OAE + ABR Advantages: OAE + ABR Disadvantages: • Low fail rate • Time • Depending on test order, • Equipment and disposable identifies cochlear, neural costs and conductive losses • Reduced effects of noise • Pass-refer screening devices available for both technologies Why is diagnostic confirmation by an audiologist skilled in evaluating infants and young children important? Vohr A failed hearing screen may be a false positive or an actual fail. These 2 findings need totally different management. Therefore, an accurate diagnosis of normal hearing, SNHL, auditory neuropathy or conductive loss is important as soon as possible to minimize parental stress and to decrease the time interval between screen fail and starting treatment. Parents of late identified children have feelings of guilt and frustration. Early Identification of Hearing Loss is Important because • Delayed identification, even of mild HL results in language delays developmental skill delays, and behavior problems. • Subsequent delays in literacy, and academic performance Grade Equivalents Reading Comprehension Scores of Hearing and Deaf Students Deaf Hearing 10.0 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 8 9 10 11 12 13 14 15 16 17 18 Age in Years Deaf Children in America 1986 Unilateral or Mild Loss • 50% of children either repeat a grade or need resource support in school • Increased behavioral and linguistic problems compared to hearing controls. Bess F, Pediatrics 1984 Early “Early Intervention” for Hearing Loss is Important because • There are dramatic benefits associated with early identification and intervention for hearing loss before 6 months of age. • Children identified and receiving services < 6 m have larger vocabularies, better comprehension and better expressive language than children identified > 6 m. Are Interventions Available to Improve Outcome? White - language scores of sev to profound (14 vs 26 m) Apizzo - better language scores at 4 if ident <2 m Moeller - 100 D/HH children with early ident - better outcomes Yoshinago-Itano - better scores at 36 m if ident <6 m Early “Early Intervention” is better !!!! AAP & JCIH Recommendations Components of EHDI Programs in the US • • • • • Universal Newborn Hearing Screening< 1 m Effective Tracking and Follow-up as a part of the Public Health System Appropriate and Timely Diagnosis of the HL < 3m Prompt Enrollment in Appropriate EI < 6m All infants will have a medical home Importance of Diagnostic Audiologic Confirmation of Hearing Loss Gravel Comprehensive Audiologic Assessment (includes case history) Birth - 5 mos 6 mos - ~ 24 mos ~ >24 mos EOAE EOAE EOAE Acoustic Immittance Acoustic Immittance Acoustic Immittance ABR: FS (AC & BC) & Neuro Visual Reinforcement Audiometry (VRA) Play Audiometry Observation of Behaviors to acoustic signals (cross-check & auditory function) ABR: FS (AC & BC) & Neuro (cross-check & document physiologic function) ABR: FS (AC & BC) & Neuro (cross-check & document physiologic function) Gravel, 2000; Gravel & Hood, 1998 “Audiologists should have experience with the assessment of infants & children with HL and the knowledge and equipment necessary for use with current pediatric assessment methods”. “Facilities that lack the expertise or equipment for assessing infants & children should establish consortial arrangements with those that do”. Pediatric Working Group, 1996 What are the components of the medical home work-up for children with congenital hearing loss? Vohr EHDI and the Medical Home Parent Groups Mental Health Primary Provider Child/Family 3rd Party Payors Deaf Community Interpreters Hospital Screening Deaf Services EI Therapists Audiology ENT Genetics The Medical Workup • Complete prenatal & perinatal hx • Family Hx of onset of HL < age 30 • Physical for stigmata, ear tabs, cleft • • • palate, cardiac, skeletal, microcephaly Refer to ENT / CT of temporal bones Refer to Genetics and Opthalmology Other: CMV, EKG What are some of the questions to ask ? • Antenatal history- maternal illness during the pregnancy or delivery • Neonatal complications, prematurity, jaundice, asphyxia, assisted ventilation, ECMO Examination for Causes • Evaluate for dysmorphic features, minor and major stigmata and syndromes • Other anomalies – visual, facial, endocrine, cardiac, kidney, hair, and skin • Particular attention to the head and neck. HL may be associated with abn. pinna, atresia or stenosis of the ear canal, ear tags, and bony growths in the ear canal. • Cleft lip and palate may have middle ear fluid What to ask about family history ? • Is there a family hx of onset of permanent HL < 30 years of age ( over 3 generations) • Are there other family members with syndromes or anomalies ? Which families may benefit from a Genetic Referral ? • All families with a child with congenital or late onset hearing loss • Families of a child with stigmata or a syndrome will benefit from the information. • Families with a child with non-syndromic HL want to know the cause ? • Some parents who are culturally deaf wish information on the risk or cause of HL. When to refer to Ophthalmology • First- Follow periodicity schedule for all patients • Some syndromes with permanent HL have specific eye findings such as heterochromia in Wardenburgs. • In Ushers the child is at risk of late onset vision loss secondary to retinitis pigmentosa. (If sign is the primary communication mode they will obviously have a problem. When to get an EKG ? • This is ordered to rule out long QT ( Jervell and Lange-Nielsen )syndrome. • This syndrome may manifest itself with apnea, passing out episodes, or a history of sudden death in a relative. Should there be additional workup ? • This needs to be individualized. • For example, A NICU infant with IUGR should have an MRI and TORCH titers to rule out CMV, toxoplasmosis etc. Children with Cochlear Implants and Meningitis • The incidence of meningitis is higher among children with cochlear implants. • The incidence of Streptococcus pneumoniae meningitis was 30 times the incidence in the general population. NEJM, July 2003 Recommendations for children with Cochlear Implants • Children < age 2 years should get pneumococcal conjugate vaccine (Prevnar) according to the routine schedules • There are guidelines for older children (CDC) • Children with cochlear transplants should be monitored and treated promptly for any bacterial infections. Amplification Choices for Families including Hearing Aids, FM Systems and Cochlear Implantation Gravel What is the Goal of Hearing Aid Fitting Ensure children receive full-time use and consistent audibility of the speech signal at safe and comfortable listening levels as soon as hearing loss is confirmed. PWG, 1996 When are Hearing Aids Fit? For newborns identified by UNHS, fit hearing aids within one month of confirmation of hearing loss, preferably before 4 months and no later than 6 months of age. JCIH, 2000 Which infants are candidates for amplification? • Significant, permanent • Some children with bilateral peripheral unilateral hearing loss, hearing loss. and minimal HL • Mild hearing loss in • Need based on some cases audiogram plus additional information: – Family choice – other disabilities/ongoing medical issues – performance PWG, 1996 Pre-Selection Children’s Hearing Aids Should Include: • Binaural fitting unless clear contraindication • Behind-the-ear style of choice PWG, 1996 Pre-Selection Children’s Hearing Aids Should Include: • Flexible response characteristics • Compression to limit overall output sound pressure level of the hearing aid (safety and comfort) PWG, 1996 Directional Microphone Technology • Improves directional hearing abilities – Hear parent speaking from front; noise from shopping mall at back of child reduced. Multiple Memory Hearing Instruments • Allows storage of more than one electroacoustic response setting • Allows switching between memories for various listening situations Digital Signal Processing (DSP) Technology • Newer hearing aids that use digital processing of incoming • No studies, to date, demonstrate better performance of digital instruments over conventional hearing aids in either adults or children • Considerably more expensive What Other Features Should Children’s Hearing Aids Include? • Safety-related features: tamper resistant – battery compartment – volume control • Physical fit (size) and color • Earmolds made of soft material PWG, 1996 How Do We Fit Hearing Aids to Infants & Young Children? • Use computerized prescriptive fitting procedure • Requires only minimal threshold data to begin, so fitting can begin early. From: Seewald, 2003 Prescriptive Fitting Procedure • Incorporate simple probe microphone measurements • Allow audiologist to: – Pre-select the response characteristics of the hearing aids – Refine or ‘individualize’ the hearing aid for the unique acoustic characteristics of each infant’s ear – Verify that the prescriptive frequency-gain and output targets have been achieved From: www.babyhearing.org Goals of FM Fitting • Child hears primary talker at level that is consistently audible above the background noise • Child able to monitor his/her own voice • Child hears voices of others who are not wearing the FM microphone Lewis et al., 1998 (Phonak AG) Why Does the Acoustic Climate (of the Home, Daycare Setting, etc.) Need to be Considered? • Infants and young children with congenital/early onset hearing loss – Are learning language for the first time – Have greater difficulty understanding speech in background noise than adults – Require a more audible (intense) signal than adults to understand speech Fail Neonatal Screening Fail Outpatient screening FS-ABR,EOAE AC & BC, tymps Repeat FS-ABR, EOAE,RECD with insert, for HA selection, tymps Observe auditory behaviors & tymps Behavioral & tymps (with mold to insert coupling) 1m Counseling 2m 3m Counseling; medical/ENT referral Begin processes for HA procurement Mold impressions, EI Program 4m HA Fitting 5m HA Check & (molds) Review habilitation, language milestones 6m Behavioral & tymps (with mold-to-insert coupling) 7m RECD, HA modification, (molds) Review habilitation, language milestones 8m Behavioral & tymps (with mold-to-insert coupling) 9m RECD, HA modification, (molds) Review habilitation, language milestones 10m Behavioral & tymps (with mold-to-insert coupling) 11m 12m RECD, HA Check, (molds) Validation measures, language milestones Set habilitation goals for year 2 Gravel, 2000 Qualifications of Audiologists and Facilities • No facility should fit hearing aids to children if it lacks the equipment for behavioral, electrophysiologic, electroacoustic, and probemicrophone/real-ear evaluation. • Facilities that lack the expertise or equipment should establish consortial arrangements with centers that do. PWG, 1996 Considerations in Determining the Appropriateness of Cochlear Implantation including Risks, Benefits & Timing Gravel What are the Candidacy Criteria for a Cochlear Implant? From: www.babyhearing.org • Limited benefit from conventional amplification following a minimum of 3-6 months use – May be sooner following deafness from meningitis • Profound hearing loss: – 12-18 months • Severe-to-Profound hearing loss – >18 months • Motivated, involved family with child enrolled in an intervention program emphasizing spoken (oral-aural) language development Cochlear Implants • Acoustic signal picked up by microphone located in headset worn at ear level • Cord carries sound from microphone to a speech processor • Speech processor digitizes sound into coded signals • Coded signals sent up to the transmitting coil • Coil sends coded signals as FM radio signals to CI under the skin • CI delivers electrical energy to the electrode array inserted into the cochlea • Electrodes along the array stimulate remaining nerve fibers in cochlea Cochlear Corp. 2002 Selecting a Cochlear Implant Center • Experienced cochlear implant team – Audiologist, speech-language pathologist, surgeon – Others: educator of the deaf, psychologist, social worker • Comprehensive program covering eligibility, surgery, device activation, and long-term habilitation. – Multi-disciplinary, family centered approach. – Knowledgeable regarding deafness, child development, and speech, language and auditory development – Offers intervention program and continued – Follow-up for changes in cochlear implant mapping Benefits • Similar to early amplification provision, children implanted at early ages with more experience tend to do better than older children who receive implants after greater period of deafness Listening to Parental Concern About Delayed Language Development Gravel & Vohr Listening to parent concern about language development • Parent concerns about hearing, speech, language, or developmental delays are strong predictors of an actual problem. • Providers must avoid statements like “Babies develop at different rates. Lets take another look in about 6 months” Clinical signs of Hearing Loss • • • • • Delayed early language milestones Unintelligible speech Uncharacteristic voice patterns Child turns TV volume very loud Child only responds to loud sounds/words or in a very quiet environment Myths about hearing and early speech language delay • We don’t have to worry because: • His older brothers and sisters talk for him • Boys develop speech much later than girls • Twins always have language delays • Grandma says that her Dad did not speak until he was 3 years old. • She has great motor milestones • I know he hears because he gets upset every time I turn on the vacuum. Assessment of language delay • • • • Administer a speech language screen Check middle ear status for MEE: Rx MEE for > 3 m refer to otolaryngology If receptive /expressive delay refer back to audiology for repeat diagnostic • Refer to early intervention for speech language therapy • Assess for other possible dx: PDD, autism • Continue to follow-up on speech/language It is important to respond to concerns about language immediately ! Most children with delays of speech and language respond to appropriate medical, audiologic, and educational interventions. A successful early screening, identification, and intervention program will ultimately permit every child with HL to develop to his/her potential. • All in-hospital screening failures should receive follow-up – Failure rate at discharge, once high has decreased to 2% or less. – Probability 1 in 5 that infant who fails NHS has hearing loss • Regardless of screening outcome, if parent is concerned regarding hearing or speech-language development, child should be referred for audiologic evaluation Question-and-Answer Early Hearing Detection and Intervention CME Teleconference Series, Part II November 12, 2003 12:00 – 1:00 pm, Central Standard Time Topics: Implementing newly developed AAP guidelines; important referrals; the role of early intervention; primary care’s role in coordination of services; parenting issues and reactions; knowledge of and support for communication choices; cost and reimbursement issues; and national resources. Faculty: Al Mehl and Mary Pat Moeller