Rinne's and Weber's Test
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RINNE’S AND WEBER’S TEST “The Sea Shell”, oil on canvas, William Bouguereau, 1871 RINNE’S AND WEBER’S TEST Introduction Rinne’s and Weber’s tests are simple tests that can be done to determine the presence of a hearing deficit. The nature of a hearing deficit refers to whether the problem is conductive or sensorineural. Both tests must be done to indicate the nature of hearing loss, however formal audiometry by a qualified audiometrist remains the best test for hearing loss. Conductive deafness is caused by an abnormality of the external or middle ear. Sensorineural deafness is caused by an abnormality of the inner ear, (ie the cochlear or the auditory nerve). See appendix 1 below for anatomy of the outer, middle and inner ear. Mixed deafness is a term used to describe a combination of conduction and sensorineural deafness in the same ear. Rinne’s Test ● A 512 Hz tuning fork is struck then placed on the mastoid process behind the (deaf) ear and when the sound is no longer heard it is placed in line with the external meatus. 1 (Note that 256 Hz and 128 Hz tunings forks are used for testing vibration sense, but are not suitable for the testing of hearing). ● Normally the note is audible at the external meatus. If a patient has nerve deafness the note is audible at the external meatus, as air and bone conduction are reduced equally, so that air conduction is better (as is normal). This is termed Rinne positive, (a normal result). ● If there is a conduction (middle or outer ear) deafness no note is audible at the external meatus. This is termed Rinne negative, (an abnormal result). Alternative methods: It should be noted that the Rinne’s test can be performed in a number of different ways. 2 Two further alternatives are: ● The tuning fork is struck and held close to the patient’s ear. It is then placed firmly on the mastoid process and the patient is simply asked to state whether it is heard better by bone conduction or air conduction. ● A more accurate, but more time consuming method of performing the Rinne test is to hold the tuning fork close to the patient’s ear and ask him to say when he can no longer hear it. It is then placed on the mastoid process and the patient states whether or not he/she can still hear it. If he cannot, air conduction (AC) is better than bone conduction (BC). If on the other hand the tuning fork can still be heard by bone conduction, then BC is better than AC Rinne’s test tells you little or nothing about cochlear function, it is primarily a test of outer/middle ear function. Be aware that the Rinne Test alone cannot reliably identify a sensorineural hearing loss. The Weber tuning fork test is essential to make this diagnosis. Weber’s Test ● A 512 Hz tuning fork is struck then placed on the centre of the forehead. Normally the sound will be perceived in the centre of the forehead. ● Nerve deafness causes the sound to be perceived in the normal ear only. ● A patient with conduction deafness will perceive the sound to be louder in the abnormal ear. If the tuning fork pressed to the middle of the forehead is heard in the good ear, and not in the deaf one, the patient has a sensorineural hearing loss until proven otherwise. Application and Interpretation Normal results: Tuning fork tests showing a positive Rinne in each ear and the Weber test referred equally to each ear, indicating symmetrical hearing in both ears with normal middle/outer ear function. Sensorineural deafness in the right ear: The Rinne test is positive on both sides and the Weber test is referred to the left ear. Conductive deafness in the right ear: The Rinne test is negative on the right (ie patient’s right) positive on the left and the Weber test is referred to the right ear. Appendix 1 Anatomy of the ear Anatomy of the outer, middle and inner ear. The 3 ear bones, (left to right) include the malleus, incus and stapes. References 1. Talley NJ, O’Connor S, Clinical Examination, 3rd ed, 1996: p. 361. 2. Bull PD, Lecture Notes of the Ear, Nose and Throat, 7th ed 1991. Dr J. Hayes Reviewed September 2012 .