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Current time:0:00Total duration:6:58

Video transcript

communication and the human voice is an amazing invention is an amazing thing communication has led to discoveries that are so important in our civilization from science to art to the creation of complex human expression through words in fact it has led our society to advance more than any other animal species on this planet so it can actually be very frustrating when you're unable to communicate and that's what actually happens in laryngitis laryngitis is inflammation itis of the larynx but what is the larynx the larynx is also known as the voice box and in this picture that I've drawn out over here you can see a human head and though there are other body parts really important in creating communication and creating sound such as for example the tongue right here the mouth the lips the jaw but one of the most important is the larynx which I'm outlining right here and like I said it's also known as the voice box now let me take a quick step back to really acknowledge what we're really looking at here I've sketched out a 2d representation of essentially human body if you if you sliced right down the middle so you see like I said I point out other structures like the tongue the jaw here's the nose this is the nasal passage up here and back here this is the esophagus where all the food goes and over here is the windpipe right here this little flap that's kind of hanging off is the epiglottis and that's important for when we swallow so we don't get food in the windpipe this little flap bends over and protects the airway to understand the larynx looking at the top view is probably the best way to go and again up here is the epiglottis that I'm highlighting right up here so this might be the view that you would get if you looked straight down onto the larynx above the epiglottis and of course in this top view here's the tongue I have it right here also over here so in peering down at the larynx at the voice box we can see this complex structure of different soft tissues this is all considered the larynx all the soft tissue right here that I'm circling but what's really responsible for pitch and different tone are the vocal cords these little white stringy things in order to create sound a person will exhale they'll breathe out air from their lungs this air will pass through the trachea right here and through this opening in the larynx this is also known as the glottic opening so air passing through this little opening creates sound and the way sound is actually produced is very similar to wind rushing through an open window if it's cracked slightly open when air goes through a very tight space it creates sound it's also similar to what you hear when releasing a balloon that's filled with air air will rush out of the balloon and create a sound and also know if you pinch the sides of a balloon right the sound can become more high-pitched and that's because the opening for the air to rush out is narrowed so it makes sense that these vocal cords would actually have to come together and narrow to be able to create sound and when air rushes through these vocal cords vibrate back and forth which can lead to different pitches and tones in the voice one final analogy that I want to use is probably the most relevant for the vocal cords that would be the analogy of a guitar in fact I would say that the vocal cords act most like a guitar than anything else the strings towards the top of the guitar are looser and really big and bulky and this creates a very low intonation low sound whereas the strings towards the bottom of the guitar are thinner they have less mass to them and they're also tighter and this creates a very high-pitched sound so this actually starts to make a lot of sense when you think about inflammation when there's inflammation of the larynx the vocal cords are also involved and of course inflammation means swelling swelling adds mass to the vocal cords and also prevents them from vibrating as well and makes the vocal cords really floppy so people who have laryngitis have a very hoarse and raspy voice so that's really the principle behind the tanks and laryngitis now there are two main types of laryngitis and I break it down into acute laryngitis meaning laryngitis that occurs suddenly and chronic laryngitis that is lasting for a longer period of time now acute laryngitis can go away fairly quickly within days maybe a week or so whereas chronic maybe lasting a longer time two weeks or longer and the causes of these two are very similar you really just want to think what could end up causing swelling of the larynx for acute there's viral causes which is in fact the most common cause of acute laryngitis so as part of the treatment antibiotics are usually not given because antibiotics don't work against viral illnesses second most common is just from overuse and this can be from just vocal strain from yelling or overuse for example if you go to a very loud place and you're having a yell at everybody and also of note whispering can actually cause acute stress on the larynx as well so patients with laryngitis are actually recommended to not whisper because it puts more strain on the voice and lastly more rarely is bacterial but like I said generally viral illnesses cause laryngitis and these can be any virus that causes the common cold if it migrates down to where the larynx is these viruses can cause infection to the larynx and laryngitis now the chronic causes are usually due to some sort of chemical or overuse or some sort of irritant so irritants are the cause of chronic laryngitis because viral and bacterial illnesses tend to resolve after a little bit of time however if a patient has chronic sinus issues sinusitis caused by viruses or bacteria this can also lead to chronic laryngitis and chronic irritants include such things as smoke from fire or different fumes chronic exposure to secondhand smoke can cause laryngitis and overuse and repeated strain of the voice for example singing or talking a lot like I'm doing right now and also reflux disease or vomiting can cause chronic laryngitis so avoiding irritants is the best way to avoid laryngitis and also maintaining proper hygiene to avoid any viral illnesses or potentially and very rarely bacterial illnesses as well