Table 2. Main characteristics of studies with test tones of 226- and 1,000-Hz.
| Author | Sample characteristics | Probe tones | Main findingsa | Classification of curves |
|---|---|---|---|---|
| Kei et al1 | 122 neonates, aged 1–6 d with OAEs present | 226 Hz; 1,000 Hz | 1,000 Hz: type 1, 225 ears; type 2, 14 ears; type 3, 3 ears; other atypical forms, 2 ears. 226 Hz: single peak, 115 ears; DP, 116 ears; multiple peak, 9 ears; invalid curves, 3 ears. |
1,000 Hz: type 1 (A), normal; types 2 and 3 (B, DP), altered 226 Hz, single peak: normal; DP, altered |
| Margolis et al2 | 65 infants, average age of 3.9 wk | 1,000 Hz | Single peak curves found in the majority of infants. Authors did not state the number of curves encountered. | Single peak: normal |
| Baldwin7 | 104 children between 2 and 19 wk with normal hearing and 107 infants aged 2–21 wk with temporary conductive hearing loss | 226 Hz; 678 Hz; 1,000 Hz | Infants with abnormal ME and normal tympanograms (type A): 94.9% with 226 Hz, 1.3% with 678 Hz, and 0% with 1,000 Hz. | Positive peak: normal Flat, descending negative peak, or undetermined: altered |
| Calandruccio et al31 | 33 children between 4 wk and 2 y and 33 adults with a mean age of 30.3 y | 226 Hz; 630 Hz; 1,000 Hz | 226 Hz: higher proportion of type 1B1G; 23.1% type 3B1G in children aged 4–10 wk and 6.8% in children aged 11–19 wk. 1,000 Hz: children showed greater variability of types, with 1B1G and 3B1G having equal distribution. |
Type 1B1G, 3B1G, 3B3G, and 5B3G tympanograms (Vanhuyse et al21) |
| Swanepoel et al29 | 510 infants, aged 0–12 mo | 226 Hz; 1,000 Hz | 87% of tympanograms displayed a peak, DP type curves present in 4.5% of cases. | Tympanogram with peak: ME normal DP type curve: ME altered |
| Alaerts et al15 | 110 infants up to 9 mo and 15 adults between 17 and 27 y with normal hearing | 226 Hz; 1,000 Hz | 226 Hz: number of cases of type A increased with increasing age; number of cases of type D decreased with increasing age. 1,000 Hz: number of cases of type D increased with increasing age. |
Types A and D: normal Types B, C, and Du: altered Types 1 and 4u: normal Types 2, 3, and 4u: altered |
| Silva et al27 | 110 neonates between 6 and 30 d with TEOAEs present | 226 Hz; 678 Hz; 1,000 Hz | 226 Hz: 47.7% single peak; 52.3% DP. 678 Hz: 25.4% single peak; 67.3% ASS; 7.3% I. 1,000 Hz: 70.9% single peak; 28.2% ASS; 0.9% I. |
Single peak and DP: normal ASS and I: normal or altered |
| Swanepoel et al8 | 143 infants between 0 and 4 wk of age | 1,000 Hz | 8% of tympanograms showed no peak. 6% were DP-type curves. 57% sensibility. 95% specificity. |
Tympanogram with peak: ME normal DP-type curve: ME altered |
| Shahnaz et al6 | 33 neonates from ICU and 16 healthy infants between 21 and 28 d; 42 infants between 6 d and 23 wk and 33 preterm neonates between 32 and 51 wk with BAEPs present compared with 16 adults between 18 and 32 y with normal hearing | 226 Hz; 1,000 Hz | Newborns and infants showed a great variability of complex tympanometric patterns with 226 Hz. With increasing test frequency, the ratio of single peak curves increased and with 1,000 Hz the rate was 64%. | Model: Vanhuyse et al21
226 Hz: 13% 1B1G and 85% complex multiple peak tympanograms 1,000 Hz: predominantly 3B1G (50%) and 1B1G (38%) |
| Garcia et al22 | 60 infants between 0 and 4 mo in the absence and presence of OAEs | 226 Hz; 1,000 Hz | OAEs present: 226 Hz: 61% A; 27% D; 8.3% B; 3.7% C. 1,000 Hz: 60% A; 11.6% D; 13.4% I; 5% B; 10% C. OAEs absent: 226 Hz: 53.3% A; 31.7% D; 13.3% B; 1.7% C. 1,000 Hz: 20% A; 2% D; 0% I; 70% B; 8% C. |
Types A, D, and I: normal Types B and C: altered Type ASS: normal or altered |
| Zhiqi et al25 | 52 infants between 42 d and 6 mo | 226 Hz; 1,000 Hz | 226 Hz: Group with normal ME: 51.06% single peak; 44.68% DP; 2.13% flat; 2.13% with negative pressure. Group with ME effusion: 77.19% single peak; 19.30% DP; 3.51% flat. 1,000 Hz: Group with normal ME: 97.87% single peak. Group with ME effusion: 98.25% flat. |
Single peak: normal tympanogram Flat: altered (ME effusion) |
| Tazinazzio et al24 | 52 infants between 11 and 51 d with OAEs present and absent; at 1,000 Hz, the number of ears was less because blocked curves were excluded (occurrence of the occlusion effect) | 226 Hz; 1,000 Hz | OAEs present and normal curves: 226 Hz, 82 ears; 1,000 Hz, 66 ears. OAEs present and altered curves: 226 Hz, 0 ears; 1,000 Hz, 6 ears. OAEs absent and normal curves: 226 Hz, 19 ears; 1,000 Hz, 8 ears. OAEs absent and altered curves: 226 Hz, 3 ears; 1,000 Hz, 13 ears. |
Types A and D: normal Types As, B, and flat: altered |
| Lewis et al30 | 26 children with Down syndrome between 6 and 18 mo | 226 Hz; 1,000 Hz | 226 Hz: ME no fluid: type B, 7 ears; type A, 17 ears. ME with fluid: type A, 0 ears; type B, 2 ears. 1,000 Hz: ME no fluid: type A, 24 ears; type B, 0 ears. ME with fluid: type B, 2 ears; type A, 0 ears. |
Type A: normal Type B: altered |
| Camboim et al23 | 118 infants between 0 and 6 mo with OAEs present and absent | 226 Hz; 1,000 Hz | 1,000 Hz: high correlation between normal curves (type A and DP) and presence of OAEs, as well as altered curves (not type A or DP) and absence of OAEs. | Types A and DP: normal Types C, Ad, As, and B: altered |
Abbreviations: BAEPs, brainstem auditory evoked potentials; ICU, intensive care unit; ME, middle ear; OAEs, evoked otoacoustic emissions; TEOAEs, transient evoked otoacoustic emissions.
a
Information taken from the Results section of publications.