![]() TDH‐39 headphones and a B‐71 bone vibrator were used to measure the AC and BC thresholds, respectively. The PTA testing was conducted by experienced audiologists in a dedicated sound‐proof room. Additionally, a calibrated 226‐Hz tympanometer (AT235H, Interacoustics, Denmark) was also used to verify the diagnosis of CHL. It was regularly calibrated based on the American National Standards Institute (ANSI S3.6, 1996). The instruments used were 256 and 512 Hz tuning forks made of steel and kept in room air.Ī two‐channel audiometer (GSI 61, Grason‐Stadler, Inc., USA) with the respective transducers was used for the PTA and AW tests. Essentially, the aim of the present study was to determine the accuracy and the agreement of TFW and AW tests in comparison to PTA. As such, the diagnostic performance of TFW and AW tests (in comparison to PTA) has not been systematically studied. In view of the advantages of the AW test, it is not known whether the AW test would outperform the TFW test when assessing patients with CHL. However, in comparison to the TFW test, the AW test has several advantages, including multiple frequencies can be tested, the sound presentation can be controlled at intended intensity levels, and it offers consistent force on the forehead surface area. Known as the audiometric Weber (AW) test, it works in the same way as the TFW test (with the bone transducer placed in the middle of the forehead). It is worth mentioning that the Weber test can also be carried out using the readily available bone vibrator of the audiometer. In this regard, the combination of the PTA and Weber tests would be useful in solving “complex” clinical cases. The presence of false ABGs could also be confirmed with the use of the TFW test, particularly in cases of unilateral hearing loss. On the other hand, a lateralized perception (to one ear) would indicate the presence of sensorineural hearing loss (SNHL) (in the other ear). For example, if the true (masked) BC thresholds could not be obtained due to the masking problems (in cases of bilateral large ABGs), a centralized perception in the TFW test would support the diagnosis of bilateral CHL. The application of the tuning fork Weber (TFW) test would be useful in verifying questionable audiograms. The presence of harmonic distortions may influence the BC thresholds and create false ABGs. The false ABGs in PTA could also be contributed by harmonic distortions produced by the respective bone vibrator (which may appear as low as 20 dB at low frequencies). In this regard, due to lower BC thresholds, inappropriate ABGs are produced, which can be misdiagnosed as conductive hearing loss (CHL). ![]() Specifically, the bone vibrator would produce vibrotactile (VT) sensation at low frequencies (as low as 25 dB). With the widely used B‐71 bone vibrator, better than expected BC thresholds would be produced (leading to false ABGs). In cases of bilateral large ABGs in PTA, overmasking is likely to occur, and masked bone conduction (BC) thresholds cannot be obtained (resulting in incomplete PTA results). In particular, masking problems and “false” air‐bone gaps (ABGs) may occur, which would affect its diagnostic accuracy. When it is combined with the Rinne test, the overall diagnostic accuracy improved.ĭespite its diagnostic usefulness, PTA has several limitations. ![]() Of note, the sensitivity and specificity of the tuning fork Weber (TFW) test can be as high as 78% and 99%, respectively. In fact, tuning fork tests such as Weber and Rinne tests are still commonly used by otorhinolaryngologists as they are inexpensive, simple to administer, and reasonably sensitive in detecting hearing loss. Prior to the wide application of PTA in clinical settings, the hearing status was assessed using the tuning fork tests. With the use of a sophisticated audiometer, the severity of hearing loss and type of hearing loss across speech frequencies for each ear are conveniently documented by PTA. Pure‐tone audiometry (PTA) has been regarded as the gold standard test for detection of hearing thresholds.
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