Tuning fork hearing test
Clinicians should remain mindful of these differences and optimize these techniques in specific clinical applications to improve TFT accuracy. Conclusion Variability exists in the reported test accuracy measurements of TFTs for clinical screening, surgical candidacy assessments, and estimation of hearing loss severity. There is high risk of bias in patient selection for a majority of the studies. Significant heterogeneity in TFT methods and audiometric thresholds to define hearing loss precluded meta-analysis. The audiometric thresholds at which tests transition from normal to abnormal ranged from 13 to 40 dB of conductive hearing loss for the Rinne test and from 2.5 to 4 dB of asymmetry for the Weber test. 1 In relation to the present study, a recommended material of the tuning fork was used (i.e., steel).
21, 22 The tuning fork test results are also influenced by the material of the tuning fork and techniques used. The sensitivity and specificity of the Rinne test for detecting conductive hearing loss ranged from 43% to 91% and 50% to 100%, respectively, for a 256-Hz fork and from 16% to 87% and 55% to 100% for a 512-Hz fork. In view of this, less reliable results had been reported when conducting the Weber test among younger children (11 years). In asymmetrical hearing loss the sound is usually lateralized to one side regardless of the placement of the vibrating fork. After a few seconds the forks are reversed. Results Seventeen studies with 3158 participants, including adults and children, met inclusion criteria. The test is performed by placing tuning forks simultaneously on both mastoids, with one fork vibrating and the other silent, but without the patients knowing which is which.
Two independent evaluators corroborated the extracted data and assessed risk of bias. Review Methods A systematic review of studies reporting TFT accuracy was performed according to a standardized protocol.
#Tuning fork hearing test manual
Data Sources PubMed, Ovid Medline, EMBASE, Web of Science, Cochrane, and Scopus and manual bibliographic searches. (2) To identify the audiometric threshold at which TFTs transition from normal to abnormal, thus indicating the presence of hearing loss. Placement of the tuning fork tines in parallel as opposed to perpendicular to the EAC results in a higher sound amplitude at the level of the tympanic membrane.Objective (1) To determine the diagnostic accuracy of tuning fork tests (TFTs Weber and Rinne) for assessment of hearing loss as compared with standard audiometry. Conclusions: Clinicians vary in their orientation of the tuning fork tines in relation to the EAC when performing the Rinne test. The 256 Hz tuning fork in parallel with the EAC as opposed to perpendicular to was louder by 0.83 dB (95 % CI: -0.26, 1.93 dB p = 0.14) for the fundamental frequency (256 Hz), and by 4.28 dB (95 % CI: 2.65, 5.90 dB p < 0.001) and 1.93 dB (95 % CI: 0.26, 3.61 dB p =.02) for the two harmonic frequencies (500 and 4 kHz) respectively. The sound intensity (sound-pressure level) recorded at the tympanic membrane with the 512 Hz tuning fork tines in parallel with as opposed to perpendicular to the EAC was louder by 2.5 dB (95 % CI: 1.35, 3.65 dB p < 0.0001) for the fundamental frequency (512 Hz), and by 4.94 dB (95 % CI: 3.10, 6.78 dB p < 0.0001) and 3.70 dB (95 % CI: 1.62, 5.78 dB p =.001) for the two harmonic (non-fundamental) frequencies (1 and 3.15 kHz), respectively. Results: 47.4 and 44.8 % of 116 survey responders reported placing the fork parallel and perpendicular to the EAC respectively.
The amplitudes of the sound delivered to the tympanic membrane with the activated tuning fork tines held in parallel, and perpendicular to, the longitudinal axis of the EAC were measured using a Knowles Electronics Mannequin for Acoustic Research (KEMAR) with the microphone of a sound level meter inserted in the pinna insert. Methods: To assess the variability in performing the Rinne test, the Canadian Society of Otolaryngology - Head and Neck Surgery members were surveyed. The present study had two goals: determine if (1) there is clinician variability in tuning fork placement when presenting the air-conduction stimulus during the Rinne test (2) the orientation of the tuning fork tines, parallel versus perpendicular to the EAC, affects the sound amplitude at the ear. Whether the orientation of the tuning fork tines affects the amplitude of the sound signal at the ear in clinical practice has not been previously reported. Background: Guidelines and text-book descriptions of the Rinne test advise orienting the tuning fork tines in parallel with the longitudinal axis of the external auditory canal (EAC), presumably to maximise the amplitude of the air conducted sound signal at the ear.