Rinne and Weber Tests - Tuning Fork| Rinne and Weber Test explained

Rinne and Weber Tests - Tuning Fork| Rinne and Weber Test explained

Weber and Rinne Test. The clinical examination of hearing loss should include differentiating between conductive and sensorineural hearing loss. There are different causes of sensorineural hearing loss, such as inner-ear disease or damage to the cochlear nerve. In all cases, the perception of sound waves via both air and bone conduction is impaired. Sounds reaching the affected ear will, therefore, be perceived to be quieter than on the unaffected side. Conductive hearing loss, on the other hand, is caused by diseases of the middle ear, such as otosclerosis or otitis media. Obstruction of the outer auditory canal, as seen in cerumen impaction, for example, can also lead to conductive hearing loss. In this case, air conduction of soundwaves from the middle to the inner ear is impaired. Bone conduction, however, is unaffected and causes sounds on the affected side to appear louder. There are two hypotheses that attempt to explain this phenomenon. First, it is assumed that impaired sound conduction causes up-regulation of the inner ear, which makes it more sensitive towards stimuli received by bone conduction. It also causes these sounds to be perceived as louder. Second, if sound waves can not easily reach the inner ear, they probably can not exit it easily either. These trapped sound waves could, therefore, make patients perceive sounds as louder. The Rinne and Weber Test can help differentiate between sensorineural and conductive hearing loss.

THE RINNE TEST 

The Rinne test enables unilateral comparison of bone to air conduction and takes advantage of the fact that physiologically, sound conduction is more efficient via air, than via bone. Place a vibrating tuning fork against the mastoid bone. Sound waves now travel to the inner ear, via bone conduction. As soon as the patient can no longer hear the sound, hold the tuning fork next to the patient's ear. The sound waves are now conducted via the air. Patients with conductive hearing loss are no longer able to hear this sound since air conduction is severely impaired.

 Therefore the Rinne test is negative. In healthy patients, but also in patients with sensorineural hearing loss, air conduction will always be more efficient than bone conduction, and, as such the sound of the vibrating tuning fork should still be heard. This describes a positive Rinne test. Alternatively, the test can be sped up by first placing the tuning fork against the mastoid bone, and then, after a few seconds, holding it next to the patient's ear on the same side. If the sound is perceived as louder, the test is positive, and air conduction is intact. Should the sound not be perceived as louder, the Rinne test is negative, and conductive hearing loss should be suspected.

The Rinne test should always be accompanied by the Weber Test, to detect the origin of hearing loss and possible inner ear damage. 

 

THE WEBER TEST

The Weber test compares bone conduction on both sides. Start by placing a vibrating tuning fork medially on the patient's head. The sound is now transmitted by bone conduction. Physiologically, it should be heard centrally -- or, in other words, equally loud in both ears. Unfortunately, the patient reports the same finding in both bilateral conductive and bilateral sensorineural hearing loss. This can be the cause of falsely diagnosing a patient as healthy. If the sound is heard louder on one side, this is called lateralization. It can have two different causes. In the case of unilateral sensorineural hearing loss, sound lateralizes to the unaffected side. For example, in right-sided inner ear damage, the sound is louder on the left side. If unilateral conductive hearing loss is present, sound lateralizes to the affected side, since, as mentioned before, bone conduction results in a sound that is perceived as louder. For example, damage to the right middle ear makes sounds louder on that side.

 Differentiating between sensorineural and conductive hearing loss is only possible by interpreting results from both the Rinne and Weber Test. To illustrate, the following test results show the clinically relevant constellations. Weber: lateralized to the right. Renee: positive bilaterally. Lateralization to the right during Weber tests could indicate conductive hearing loss on the right side, or, left-sided sensory neural hearing loss. A bilaterally positive Rinne Test indicates that air conduction surpasses one conduction on both sides, thereby ruling out conductive hearing loss. This test result constellation supports left-sided sensory neural hearing loss, as seen in inner ear damage. Weber: lateralized to the right. Rinne: negative on the right. Lateralization of the Weber test to the right indicates either conductive hearing loss on the right side or, left-sided sensorineural hearing loss. The negative Rinne Test on the right side underlines that air conduction is inferior to bone conduction on this side, making conductive hearing loss more likely. This can be seen in, for example,right-sided middle ear damage. Weber: no lateralization. Rinne: positive bilaterally. A normal Weber test can be either physiological or indicate a bilateral conductive or sensorineural hearing loss.

The bilaterally positive Rinne test signifies that air conduction surpasses one conduction on both sides. This rules out significant conductive hearing loss. In conclusion, the test results indicate either normal findings or bilaterally equal sensorineural hearing loss. Weber: no lateralization. Rinne: negative bilaterally. Contrary to the last case, the bilaterally negative Renee test means that air conduction is inferior to bone conduction on both sides, indicating conductive hearing loss. The unremarkable Weber test points to asymmetrical conductive hearing loss. The Rinne and Weber tests are easy and quick methods for differentiating simple forms of conductive and sensorineural hearing loss. Complex illnesses, such as combined conductive and sensory neural hearing loss, often result in test results that are difficult to interpret.

So that in total is our Rinne and Weber test and it's one of the most important and well-known methods. I hope you enjoyed this post and there will definitely be more like this coming up as well as analyses of great information about the Rinne and weber test. so please do subscribe if you want to see more and share this post if you liked it thanks for reading.........