Patients may present because others have noticed they are not paying attention or missing details of conversations. Hearing loss may be gradual and insidious. The vestibulocochlear nerve transmits nerve signals from the semicircular canals and cochlea to the brain.The cochlea is responsible for converting the sound vibration into a nervous signal.The semicircular canals are responsible for sensing head movement (the vestibular system).The malleus, incus and stapes are the small bones in the middle ear that connect the tympanic membrane to the structures of the inner ear.The Eustachian tube connects the middle ear with the throat to equalise pressure.The external auditory canal is the tube into the ear.The pinna is the external portion of the ear.The basic structures, from outside in, are: Sensorineural hearing loss is caused by a problem with the sensory system or vestibulocochlear nerve in the inner ear. Putting earplugs in your ears causes conductive hearing loss. The sensory system may be working correctly, but the sound is not reaching it. Images from, are two main categories of hearing loss: conductive hearing loss and sensorineural hearing loss.Ĭonductive hearing loss relates to a problem with sound travelling from the environment to the inner ear. Watch a video on rinne and weber’s test courtesy of This is because the conduction problem masks the ambient noise of the room, whilst the well-functioning inner ear picks the sound up via the bones of the skull causing it to be perceived as a louder sound than in the unaffected ear. This is because the affected ear is less effective at picking up sound even if it is transmitted directly by conduction into the inner ear.Ĭonductive Hearing Loss: Loudest sound in affected ear (hears vibrations only). Sensorineural Hearing Loss: loudest sound in unaffected ear. Normal Response: sound is heard equally at both ears. Ask client if the sound is heard better in one ear or the same in both ears.Hold the fork for 2-3 seconds to allow sufficient time to make a mental note of the stimulus intensity. Place the vibrating tuning fork on the middle of the patient’s head.The Weber test is used to determine a patient’s hearing ability by bone conduction and is useful in detecting a unilateral (one-sided or asymmetrical) conductive hearing loss and unilateral sensorineural hearing loss. Weber’s test is a quick hearing test that is performed with Rinne’s test. Positive Hearing Loss or “Reversed Rinne”: When a patient hears a louder and longer tone when the vibrating tuning fork is held against the mastoid bone than when it is held next to the ear. Normal: A patient with normal hearing will hear the tone of the vibration longer and louder when the tuning fork is held next to the ear than that against the mastoid bone. The patient is asked whether the sound is louder behind or in front – referring to bone and air conduction respectively.After the sound is no longer appreciated the vibrating top is held one inch from the external auditory meatus.Ask the client to tell you when the sound is no longer heard.Place the vibrating tuning fork on the base of the mastoid bone.Strike a 512 Hz tuning fork softly (knees or elbows slightly not the table) otherwise the vibrations will be excessive and cause the patient discomfort.Sit the patient in a chair comfortably.Explain the procedure to the patient to promote cooperation.To evaluate a patient’s hearing ability by air conduction compared to that of bone conduction. It should always be accompanied by a Weber’s test that is used to detect a sensorineural hearing loss, confirming the nature of hearing problem. Rinne’s test is a hearing test that compares the perception of sounds as it compares the patient’s ability to hear a tone conducted via air and bone through the mastoid process.
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