Presentation on theme: "1000 Hz Tympanometry and EHDI Programs"— Presentation transcript:
1 1000 Hz Tympanometry and EHDI Programs Wendy D. Hanks, Ph.D.Stephanie Adamovich, M.S.Pamela Buethe, M.S.Gallaudet UniversityWashington, D.C.
2 Faculty Disclosure Information In the past 12 months, we 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 our presentation.This presentation will not include discussion of pharmaceuticals or devices that have not been approved by the FDA or unapproved or “off-label” uses of pharmaceuticals or devices.
3 Developmental Milestones OverviewRationaleMethod and InterpretationSample CasesAccess to Speech InformationHealthy earsDevelopmental Milestones
4 What is the Prevalence of Middle Ear Effusion in Infants? Full term babies (Well babies)Prevalence of conductive hearing loss is 17 per 1000 (RIHAP, White et al., 1993)NICU babies (Premature, Sick babies)Prevalence of conductive hearing loss is 36 per 1000 (RIHAP, White et al., 1993)
5 Importance of Identifying Conductive Hearing Loss Those children whose MEE is not resolved are at developmental riskInfants failing NHS due to conductive loss are at high risk for persistent or fluctuant mild to moderate hearing lossIn the RIHAP studies, conductive losses ranged from dB HL with a mean of 30 dB for HzDoyle et al. (2004) found that 58% of neonates identified with effusion within the first 48 hours of life went on to have chronic otitis media during the first year of life with thresholds exceeding 25 dBHL at 1, 2 and 4 KHz (by 9 months of age)
6 What is the Prevalence of Middle Ear Effusion in Infants? Roberts et al. (1995) report high rate of MEE (amniotic fluid) on day 1 in normal newbornsParadise et al. (1997) report prevalence of MEE at 3 months of age15% suburban33% urban
7 Importance of Identifying Conductive Hearing Loss OAE results are influenced by the presence of MEETEOAEs are absent in approximately 70% of children with abnormal tympanometry (Koivenen et al., 2000; Daly et al., 2001)If using OAEs as primary screening assessment, a significant percentage of the failures may due to MEE (Sutton, Gleadle & Rowe, 1996)
8 Prevalence Possibly Associated With Length of Stay in NICU Sutton et al. (1996) found that infants in the NICU >30 days had 4 times the risk of having abnormal tympanograms (678 Hz probe tone)Yoon et al. (2003) found that of 82 NICU graduates, 37% later had abnormal tympanometry in one ear with 29% having abnormal tympanograms AU
9 Why Worry?If the majority of conductive hearing losses will be resolved in 6 weeks, or prior to rescreening?
10 Is the Answer: A) We may never get to evaluate the baby again B) Those children whose MEE is not resolved are at developmental riskC) Audiologists need an excuse to play with the babiesD) All of the aboveE) A & B
11 The Answer is: A & B A) We may never get to evaluate the baby again B) Those children whose MEE is not resolved are at developmental risk
12 What procedure should I follow? Be a good counselor: If a MEE is detected during NHS, DO NOT indicate to the parent that all is well except for a little fluid. It is vital that the infant returns for further evaluation.See Margolis et. al (2003) for case studies
14 Interpretation Issues Not Under Our ControlInconsistent tympanogram patternsOtoscopic correlationVisualization of the tympanic membrane incomplete or unachievableUnder Our ControlKnowing the norms and applying them appropriatelyControlling factors that affect successful completion
15 Peak Static Acoustic Admittance Based on the calibrated equivalent ear canal volume2cc or 2 ml for 226 Hz probe tone3 times larger for 678 Hz4.4 times larger for 1000 HzPositive vs. Negative TailResearch shows that negative tail gives the most accurate measurementEquipment manufacturers use the tail of the starting (initializing) pressure
16 Why Is Peak Static Acoustic Admittance Important? Altered by ear diseaseIncreases with discontinuityDecreases with space occupying lesion in the middle ear
17 1000 Hz Tympanograms 2-6 Week Old Infant Norms Positive Tail Negative Tail95% = 3.95 – 2.2 = % = 3.95 – 1.4 = 2.555% = = % = = .55Data from Zapala DA, Rhodes, K, Cihocki B. "Tympanometry and Otoacoustic Emissions predict Hearing Loss in thePerinatal Period." Poster presented at the International Auditory Evoked Response and Otoacoustic Emissions StudyGroup, Memphis, TN, 1997.
18 1000 Hz Tympanograms Neonate Norms Data from Rhodes MC, Margolis RH, Hirsch JE, Napp AP. “Hearing Screening in the Newborn Intensive Care Nursery: Comparison of Methods. Otolaryngology Head & Neck Surgery 120, , 1999
19 Recent Research Data Reveals… MUST have defined PEAK to use these…Margolis, Bass-Ringdahl, Hanks, Holte, & Zapala (2003)5th percentile for NICU babies and full-term babies is .6 mmhos (peak to negative tail)Kei, Allison-Levick, Dockray, Harrys, Kirkegard, Wong, Maurer, Hegarty, Young, & Tudehope (2003)5th percentile for full-term babies is .39 mmhos (peak to positive tail)
27 Factors that Influence Infant Assessment Why 1000 Hz instead of 226 Hz? Ear Canal/Middle Ear CharacteristicsInfant ear canals are cartilaginous and do not ossify until at least 4 months of ageThe middle ear space is smaller in volume and may contain mesenchymeVibratory motion of the external ear may add to the resistive componentThese differences make the mass and resistive components more prominent in infants than adultsHolte et al., 1991
28 Factors that Influence Infant Assessment Probe Says “Leak” or “Occluded” Ear Canal Volume Too SmallAltitude (4950 ft.)Adjustments in calibration based on adult earsMay not affect tympanograms from adults, but may affect infantsRounding ProcedureRounds ear canal volume to the nearest tenthVolume increases with frequency, not always proportionatelyFluid in the middle ear may be pushing out on TM, making ear canal volume even smaller
29 Factors that Influence Infant Assessment Probe Says “Leak” or “Occluded” Shape of the neonatal ear canalSlit-like, not as cylindrical as adultsProbe PlacementStanding Waves Rounding Procedure
30 Factors that Influence Infant Assessment Probe Says “Leak” or “Occluded” Room noise in NICU or Well-Baby AreasClose to probe frequencies, may interfereGSI 33/ TympStar may interpret as feedbackAs probe frequency increases, intensity of the output decreasesRoom noise adds intensity; equipment interprets as occluded
31 Factors that Influence Infant Assessment What Factors that Influence Infant Assessment What ??s Still Need to be Answered?How do I interpret the “other” tymps?Can I use the norms interchangeably?Do the norms apply to all pieces of equipment?Do we need norms for TPP?Other???
32 Including it in YOUR Program When to perform & by whom?Performed by an audiologist vs. screening technicianBirth screen, rescreen appointment or the diagnostic assessmentReferral delays for ABRENT often cannot make accurate diagnosis if OM not present
33 Including it in YOUR Program Sensitive to baby movement & cryingSleeping, nursing, laying quietMay result in a false peakPressure change direction and rangePositive to negative+200 daPa to -400 daPa (sometimes +400 to -600 daPaPressure speed not critical600 or 200 daPa/sec may be utilizedCheck ReliabilityAlways repeatTympanometry protocol recommendations can be found at:
34 Case Studies: Normal tracings 2 month old referred for rescreenPresent/robust TEOAEs
35 Case Studies: Normal tracings 2 month old referred for diagnostic ABRAbsent TEOAEs for the right earUnilateral moderate-severe SNHL
36 Case Studies: Normal tracings 10 day old referred for rescreen follow-upAbsent TEOAEs LEPresent TEOAEs REResults consistent with birth screeningReferred for diagnostic ABR
37 Case Studies: “Other” tracings 2 month old referred for diagnostic ABRPresent acoustic reflexes at 1000 & 2000 Hz (1000 Hz probe tone)ABRClicks down to 20 dBnHL500 Hz TB down to 25 dBnHLPresent TEOAEs
38 Case Studies: Shallow 4 month old referred for diagnostic ABR ABR TBs: 1k, 2k, 4k Hz down to dB nHL.5 k Hz down to 40 dB nHLChild awoke prior to b/c assessmentAbsent TEOAEsReferred to ENT for MEE
39 Case Studies: Shallow/retraction 2 month old referred for diagnostic ABR15 dB difference between a/c and b/c click stimuliMild-to-moderate CHLReferred to ENT for MEE
40 Case Studies: Flat 3 mo referred for diagnostic ABR Absent ABR to click and TB stimuliReferred to ENT for medical work-up of profound SNHL with MEE overlay
41 Conclusions1000 Hz tympanometry is effective and reliable in newborns – Normative data is available!Peak to negative tail calculations appear most accurateIncorporate the procedure routinely for diagnostic assessmentsCorrelate tracings with other diagnostic measurements