To perform the Weber test, follow these steps: Rinne: Right ear: AC > BC (Rinne positive) left ear: BC > AC (Rinne negative) Weber: Lateralization to the left ear Diagnosis: Left conductive deafnessĬontinue reading here: Inspect the Tympanic Membrane B, In the presence of a sensorineural loss, the sound is heard better on the opposite (unaffected) side. A, In the presence of a conductive hearing loss, the sound is heard on the side of the conductive loss. When a vibrating tuning fork is placed on the center of the forehead, the normal response is for the sound to be heard in the center, without lateralization to either side. B, In the presence of a sensorineural loss, the sound is heard better on the opposite (unaffected) side.įigure 11-13 The Weber test. Rinne: Right ear: AC > BC ( Rinne positive) left ear: AC > BC (Rinne positive) Weber: Lateralization to the left ear Diagnosis: Right sensorineural deafnessįigure 11-13 The Weber test. In summary, consider the following two examples: The Rinne and Weber tests are then carried out as indicated, using the silent tuning fork. To test the reliability of the patient's responses, it is occasionally useful to strike the tuning fork against the palm of the hand and hold it briefly to silence it. In patients with unilateral sensorineural deafness, the sound is not heard on the affected side but is heard by, or localized to, the unaffected ear. Thus, the affected ear hears and feels the vibrating tuning fork better than does the normal ear. In an ear with a conductive hearing loss, the air conduction is decreased, and the masking effect is therefore diminished. This tends to mask the sound of the tuning fork heard by bone conduction. In normal conditions, there is considerable background noise, which reaches the tympanic membrane by air conduction. The explanation for the Weber test effect is based on the masking effect of background noise. The Weber test is illustrated in Figure 11-13. You have created a conductive hearing loss on the right by blocking the right canal the sound is lateralized to the right side. Occlude your right ear and place a vibrating tuning fork in the center of your forehead. Sound is lateralized to the affected side in conductive deafness. If the sound is not heard in the middle, the sound is said to be lateralized, and thus a hearing loss is present. Hearing the sound, or feeling the vibration, in the middle is the normal response. Ask the patient to indicate whether he or she hears or feels the sound in the right ear, in the left ear, or in the middle of the forehead. Stand in front of the patient and place a vibrating 512-Hz tuning fork firmly against the center of the patient's forehead. Head CT not routinely necessary, but may be considered for some patients based on individual characteristics.In the Weber test, bone conduction is compared in both ears, and the examiner determines whether monaural impairment is neural or conductive in origin.Tinnitus, dizziness, and vertigo are common. Every effort should be made to ensure that conductive hearing loss (eg, ruptured tympanic membrane, or congestion of the middle ear or ear canal) is not present by using a tuning fork.Sudden Sensorineural Hearing Loss (<72 hrs) : If congested, assist middle ear fluid buildup removal (e.g.Treat mechanical factor blocking external sound.Differentiate between conductive and sensorineural hearing loss.CT scan for unexplained conductive hearing loss.Serologic testing for Syphilis, Sjögren’s syndrome.CBC to evaluate for anemia or infection.Air and bone conduction are both tested.Ĭonsideration for these tests should be based on history and physical Performed by an audiologist in a soundproof environment.Movable TM only with negative pressure = blocked Eustachian tube.Hypermobile TM = ossicular chain disruption.Nonmobile = fluid in middle ear, mass in middle ear, stiff/sclerotic TM.Then, release the pressure and the negative pressure pulls the TM outwards.First, use positive pressure to force air into the EAC to push down the TM.In conductive hearing loss, humming is louder in the affected ear.In sensorineural hearing loss, humming is louder in the unaffected ear.Hum test is conducted by asking the patient to hum and tell you in which ear the humming sounds louder.Hum test comparable to Weber test in diagnostic accuracy of new onset unilateral conductive hearing loss.5.2 Sudden Sensorineural Hearing Loss ( air conduction).
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