Weber and Rinne Test – Clinical Examination
Topic: Weber and Rinne Test – Clinical Examination
Weber and Rinne Test is must if you have issues. There are 1000’s of people taking benefits from this video. In this video you will be able to see clinical examination of hearing loss.
Weber and Rinne Test – Clinical Examination
The clinical examination of hearing loss should include the distinction 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 through the air and bone conduction is affected. Therefore, sounds reaching the affected ear will 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. Blockage of the external ear canal, as seen in earwax impaction, for example, can also lead to conductive hearing loss. In this case, air conduction of sound waves from the middle ear to the inner ear is affected. However, bone conduction is not affected and makes sounds on the affected side appear louder.
There are two hypotheses that try to explain this phenomenon. First, impaired sound conduction is assumed to cause positive regulation of the inner ear, making it more sensitive to stimuli received through bone conduction. It also makes these sounds feel louder. Secondly, if sound waves cannot easily reach the inner ear, they probably cannot easily exit either. Therefore, these trapped sound waves could make patients perceive the sounds as louder.
The Rinne and Weber tests are quick and easy methods to differentiate simple forms of conductive and sensorineural hearing loss. More complex diseases, such as combined conductive and sensorineural hearing loss, often result in test results that are difficult to interpret.
Weber and Rinne Test Tuning Fork for USMLE
Weber and Rinne Test Tuning fork for conductive hearing loss and sensorineural hearing loss. They are also discussing absolute bone conduction (ABC) and the Schwabach test for hearing loss.
Conductive hearing loss includes the area from the external ear to the stapes. Sensorineural hearing loss includes the cochlea and the cranial nerve eight. Using the weber and rine are tuning fork test, you can determine whether the problem is conduction hearing loss or sensorineural hearing loss.
Air conduction occurs when the sounds waves go through the external ear to the cochlea and the sensorineural area. Therefore air conduction tests conduction and sensorineural hearing loss. In bone conduction, the sound waves travel through the mastoid, bypass the external ear, and activate the cochlea directly.
Therefore bone conduction only tests sensorineural. RINNE TEST Place tuning fork on mastoid until the the patient can no longer hear. Then place the tuning fork next to the the external auditory meatus and see if the patient can continue to hear. Normally air conduction is two times longer than bone conduction.
If bone conduction is greater than air conduction, then it is called a negative Rinne test, and there is a conduction hearing loss. Conversely, if air conduction is greater than bone conduction, then it is a positive Rinne test, then the patient is either normal or sensorineural hearing loss.
If there is severe damage to the cochlea, then there can be a false positive. WEBER TEST Strike tuning fork on the midline of the the forehead. Normally the sound will travel to both cochlea equally, and the sound will be heard equally (no lateralization). In the sensorineural hearing loss, the lateralization will go to the good ear. However, if there is conductive hearing loss, the sound will lateralize to the bad ear.
Weber and Rinne Test Tuning Fork for USMLE Transcription
All right, so today what we’re going to cover is the can be related to the ear specifically it’s going to be all the tuning fork tests, so today we’re only going to look at the tuning fork test, which is a clinical test that allows you to differentiate whether the patient has a conductive hearing loss a sensory neural hearing loss or even a mixed hearing loss is sometimes possible.
So let’s first talk about what is conductive hearing loss is and what a sensory neural hearing loss, so here we have a patient’s ears. Then here is the head right now you have the ear this is the outer ear, right here then you have your meat here which is the tract here the tympanic membrane here are your ossicles that go like this by the stay piece is a final one, So then this will go into the cochlea, and you have the vestibular apparatus right there so this is just a general look at it now.
Before I continue, I’m going to do this real quick I want to make a quick copy of this; I don’t wanna have to keep drawing this so okay, so I’m just going to copy right now, and so I’ll keep using the same picture over and over again so now what is conductive hearing loss and what is sensory neural and also I should add theirs is the cranial nerve eight is right over there coming off the copier so conductive hearing loss is any hearing loss which is going to be between the stay PS and the outer ear, so this is going to be conductive, and so that includes the external ear.
This part is the external ear; this is a middle ear, and this is the inner here, which includes the external ear and the middle ear. Sensory neural hearing loss is pretty much the cochlea and the cranial nerve, so this is just the cochlea and the cranial nerve 8 and so using these tests, we can use the tuning fork you can differentiate.
Whether the problem is in this area or the central area, or in the conductive area so let’s begin; let’s first talk about the different types of conductors, so let me go ahead and just paste that there so we have two types of conduction the first type is called air conduction and the second type is called bone conduction so how do you get a – how do you get to sense air conduction well the way to get air conduction is you take the tuning fork you know to tap it against your knee or your elbow whatever you prefer, and you put it right outside the ear so.
When you put it outside the ear, the ways are going to travel through. You know the tympanic membrane and hit the tympanic membrane causing a vibration of the ossicles, and then it’s going to get into the finally given to the cochlea. So hence, the air conduction goes through the conduction zone, the conduction area that we talked about, and the sensory neural area.
How do we elicit bone conduction well with the bone conduction?
So what you will do is you’ll put it below the ear on the mastoid now when you put of course verse you know tap it makes sure vibrates then you put it you know behind the ear on mastoid and now what it will do is a patient will hear. Still, he won’t hear it through the tympanic membrane; you’ll hear directly through the bone. It will directly activate the coffee, yet so with bone conduction, go to the conduction part; all you’re getting is the sensory neural part, so bone conduction only tests sensory Niro.
While air conduction is testing both now, the way I like to think about it it does help me a little bit is I just think air Kundera conduction only test conduction and bone conduction only test sensory neural now in normal conditions okay in normal condition conditions your air conduction, okay your air conduction is about two times greater than your bone conduction, so this is under normal conditions okay so if you’re Eric and this makes sense because obviously, this is you know.
This is the normal way that you hear so normally you hear better through the regular ear than through the bone now what does it mean if we do this and your bone conduction is greater than your air conduction well that means you’re able to hear better through your bone then you can through your ear and okay well first of all it says that since your needle is fine because you can hear because you’re able to hear through the bone but if you’re hearing it better than air conduction then that means the problem is somewhere so if your bone conduction is greater than your air conduction that means you have a problem in the conduction of your of the sound now if your air conduction is greater than your bone conduction then that means it’s either going to be normal or you have a sensory neural hearing loss because remember bone conduction also requires sensor in your activation so if that’s bad then you know both bone conduction Eric connection would be lower but bone conductor still should be more lower than the air conduction so pretty much the you know there’s two options that you can have I mean to really make this simple there’s two options you can have either air conduction could be better or bone conduction could be better if air conduction could be better we call this I’m just going to raise this because I wrote there we call this a positive Rinne test so if air conduction is better we call it a positive Rinne test and if bone conduction is better we call it a negative Rinne test okay now so if the Rinne test is negative then that means you diagnose a conduction problem but if it’s positive either the patient is normal or there’s a sensory neural issue now just general how do you do the Rinne test I should I should go over that first in the Rinne test first you test for bone conduction so you put the tuning fork behind the mastoid and then you continue to continue to let it ring until he can’t hear it then you move the fork to the outer ear and you ask the patient if you can still hear if you can still hear then that means it’s positive Rinne tests those either normal or sensory neural tissue but if you cannot hear it then that means the bone conduction was better and so then that’s a negative Rinne test and that means he has a conduction issue now so that’s kind of a overview I should have kind of touched it before of the Rinne test now there is another tuning fork test which is then immediately after Rinne which is called the Weber test now how does the Weber test Oh real quick sorry we’ll talk about one other thing if you have severe damage if you have severe damage to your copy that this is severe then you could get a false negative you know bone conduction grades and air conduction so that’s only if it’s a very severe sensory neural damage otherwise it’s pretty safe to go so now we can move on to the Weber test so let me just get a quick print down here so again we have the head here you have the outer ear middle ear and the inner ear now in this Weber’s test what you do is you take the tuning fork you strike it make sure it’s vibrating and you put it on the top of the head now if the patient is normal then what will happen is the vibration will go to both ears actually sorry won’t go to the ear it will go straight I should raise that it will go straight to this uh coffee yet and I’ll just draw something real quick and it’ll go because remember we’re not putting it at the ear so the Weber test is skipping the conduction zone and going straight to the sensory neural aspect of the test so in a normal situation there will be both ears would be equal both ears will hear it equally in other words there’ll be no lateralization now let’s think about it if you have a sensory neural problem okay and let’s say for this example you have a central issue in the let’s say that’s the right here so you eat your your sensory neural capacity is blocked what’s going to happen then will you hear it on the right hand so this is a right this is a lab will you here on the right side no you’re only going to hear it on the left side so in this test if there’s a central issue it’s going to lateral eyes to the good ear so not the illness patients complaining up but the opposite if whatever whichever one that may be and in this scenario it’s the left ear now what if you have a conductive loss if you have a conductive hearing loss so you know the entire apparatus here so it goes like that so let’s just say that you have a problem here well this is what’s going to happen your your sensory needle is working fine right so you will still come down the signal will still come down and it will reach here but you’ll hear it better on this side because you don’t have noise coming from this side clouding the you know it’s not competing with any information whereas this one it is competing with the information coming from the outside air and on top so in conducting hearing loss it’ll actually lateral eyes to the bad ear and so this is a good way to differentiate that as well now after this there’s another test that occurs this is called the absolute bone conduction it’s written short ABC so absolute bone conduction in this test you do the bone conduction and you’re comparing it who you’re comparing it to where you’re comparing the patients in our patients bone conduction with the examiners bone conduction but there’s one little caveat here which which is which is important how making it read here the tragus which is that little tag this comes off of your ear must be a clue so the ear must be occluded in other words you need to rule out any air conduction so you got to come over here you got to block the ear so that the patient can’t hear and what you do is you will do the bone conduction of the patient ask them when he can stop hearing it and then you put it on to yourself if you’re the examiner and you will see if you can continue hearing it now if if there is conductive hearing loss then you both it will be the same duration so and obviously if it’s normal right you guys should be both normal so there’s normal and conductive hearing loss in the same duration but let’s say you take it away from the patient you put it two years and you can still continue to hear it then that is a sensory neural hearing loss so in a sensory neural hearing loss it is a shorter duration so you would actually continue to hear it and therefore the patient’s ability to hear that is shorter so that is the ABT test now this slight variation very slight is going to be the schwa back test schwa back test you do the same thing with one slight difference the ear is not occluded now in this one if if it’s the same duration so if it’s normal there will be the same duration now if it’s sensory neural hearing loss then it will be sure just like the previous one so there’ll be a shorter duration so the patient will not be hearing as long as you will but if there’s conductive hearing loss then it’s actually longer the patient will be hearing it longer than you and so in this case maybe you want to introduce off first and ask the patient if you can continue to hear so let’s do a recap on all the different tests cuz we kinda to a few things here so we have the Rinne test we have the Weber test we had the absolute bone conduction and the floor back okay so now let’s go through the normal findings the conductive hearing loss and what you can expect to find in sensory neural hearing loss so in the normal findings for Rinne and on like haven’t advanced so in the normal findings for Rinne test the absolute the at the air conduction is going to be greater than bone conduction and remember the same thing is for since you’re nearing loss so for both of them the air conduction is greater and we call this a positive Rinne both of these would be a positive Rinne but in the conductive hearing loss the bone conduction is greater than air conduction and this is a negative Rinne and if you remember I said that number air conduction is for the conduction heat conductive hearing loss and bone conduction is for the sensory neural hearing loss or in this case normal as well now let’s talk about lever now in the normal case there will be no lateralization so both ears will hear it equally in conductive hearing loss it’s going to lateral eyes to the bad ear because remember the bad ear the sensory neural still works and the Weber only test for the sensory neural but in sensory neural hearing loss it’s obviously the bad ear is not going to work so it’s going to lateral eyes to the group ear now in absolute bone conduction whether you have normal or conductive hearing loss it’s you’re going to have equal you and the patient will both hear it at the same time but in sensory neural hearing loss it’s going to be the patient will hear at a much shorter duration and that’s the same for absolute bone conduction and schwa Beck’s test members well Beck’s is when you don’t include the ear and the absolute bone conduction is when you to occlude to here and so even with drawbacks you get equal the only difference is with a conductive hearing loss it’ll actually be lengthened so that’s a quick review of the different tuning fork tests when you’re when you’re looking for distinguishing conductive hearing loss and sensory neural hearing loss.