![]() As soon as the patient signals that he is unable to hear the fork anymore the vibrating fork is transferred immediately just close to the external auditory canal and is held in such a way that the vibratory prongs vibrate parallel to the acoustic axis. The patient is advised to signal when he stops hearing the sound. As soon as the fork starts to vibrate it is placed at the mastoid process of the patient. It should not be struck against metallic object because it can cause overtones. This is the maximum vibratory area of the tuning fork. While striking care must be taken that the strike is made at the junction of the upper 1/3 and lower 2/3 of the fork. It should be struck against the elbow or knee of the patient to vibrate. Under normal circumstances, air conduction is better than bone conduction. ![]() It is designed to compare air conduction with bone conduction thresholds. Rinne’s test: is a tuning fork test used to clinically test hearing deficiencies in patients. The following tests can be performed using a tuning fork: Will give a rough estimate of the patient’s hearing acuity The vibrating fork should be held parallel to the acoustic axis of the ear being tested.ģ. It is this area of the fork which is capable of maximum vibration. The fork should be struck at the junction of upper 1/3 and lower 2/3 of the fork. ![]() The tuning fork must be struck against a firm surface (rubber pad / elbow of the examiner). It should be capable of maintaining the vibration for one full minute It should vibrate at the specified frequencyģ. Sensitivity for frequencies above 1024 Hz is rather poor and hence is not used.Ģ. Frequencies below 254 Hz are better felt than heard and hence are not used. This test can in fact be performed by using tuning forks of the following frequencies (254 Hz, 512 Hz, and 1024 Hz). Tuning fork tests are performed in order to subjectively assess a person’s hearing acuity. Tondroff identified four major bone conduction components :Ĥ. ![]() Tondroff by his classic studies offered the most detailed and complete explanation of the working mechanism of bone conduction hearing. It was later left to Tondroff who stressed the importance of tuning fork as a diagnostic tool in the field of otology. This achievement did not attract that much attention during his times. He was the first to claim the diagnostic possibility of using a tuning fork. Schmalz an otologist from Dresden Germany in 1845 introduced the tuning fork test in otology which he later named as Weber in honor of Weber. He attempted to prove that air borne sound was perceived by the vestibule and semicircular canals and bone conducted sounds by the cochlea. Weber an anatomist from Leipzig Germany described the same phenomenon as Wheatstone. He concluded direction of sound is perceived by a maximally vibrating ear drum. In 1827 Wheatstone a London based physicist investigated the mode of vibration of ear drum using a tuning fork. It was the Italian physician Capivacci in 1550 who suggested that extraneous sounds can be used to determine whether deafness is due to middle ear / inner ear causes. Vibrates real close to its fundamental frequencyģ. Physicist Venturi from Modena Italy in 1802 proved that perception of direction of sound was due to the fact that one ear is hit by more intense sound than the other. He is considered to be the father of experimental acoustics. He analysed and reported the mode of vibration of tuning fork around its nodal points. The exact physics of tuning fork was studied by the German Physicist E.F.F. Clinical otologists started believing that they had a diagnostic tool that could differentiate middle ear deafness from inner ear ones. These wooden pitch pipes caused lots of errors due to temperature and humidity changes which could affect these wooden pipes. Before this discovery musicians relied on wooden pitch pipes to identify the frequencies. Invention of tuning fork by John Shore in 1711 a trumpeter changed the whole scenario. Since this differentiation had very little therapeutic value for otolaryngologists those days, little progress was made in this direction. This knowledge was also widely available those days. Air conduction and bone conduction threshold measurements could differentiate middle ear from inner ear causes of deafness. Right from 17th century onwards it was established that humans perceive sound both via air conduction and bone conduction. The three commonly performed tuning fork tests include: Rinne test, weber test and Absolute bone conduction test. All the commonly performed tuning fork tests are discussed in detail. This article reviews the history of tuning fork tests, its current status as a clinical examination tool.
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