I am Dr. Anju Ely, moderator for this evening's webinar on CBCT Interpretations and Relevance in DSM. I'm joined with our speaker, Dr. Dania Tamimi. If you are able to see and hear me right now, that means you've successfully logged into the meeting. All participants' audio has been muted to ensure everyone can hear us clearly. If you're unable to see me, please try refreshing your browser. It is possible you may need to refresh your browser a couple of times. If refreshing your browser does not resolve this issue, click the link below the video that reads, connect directly to the webinar platform. This will connect you to the webinar via Zoom. However, you will need to return to the conference's IO platform if you would like to use the Q&A feature. The platform we are using for this webinar allows you to submit questions anonymously. To do so, make sure you are not in full screen mode and click the Ask button on the right-hand side of the screen. You can also upvote a question by clicking on the up arrow to the left of each question entered. We will respond to questions either within the online platform or verbally at the end of the presentation. And finally, the AADSM does not endorse any services, products, devices, or appliances. The use, mention, or depiction of any service, product, device, or appliance during this webinar should not be interpreted as an endorsement, recommendation, or preference by the AADSM. Any opinions expressed or communicated regarding any product, device, or appliance during the webinar is solely the opinion of the individual expressing or communicating that opinion and not that of the AADSM. Whenever possible, presentations should be supported by evidence. In instances where evidence is lacking, speakers have been asked to verbally disclose that their presentation is case-based or based on clinical experiences so that you can use independent clinical judgment to make decisions for your practice and patients. And now, I'll turn it over to Dr. Tamimi. Thank you. All right. So, good evening, everybody. It's such a pleasure to be here and to share with you. As Dr. Elias said, I am Danya Tamimi. I'm an oral and axillofacial radiologist out of Orlando, Florida, and it's such an honor to be part of this. So today, I'd like to share with you basically what I do. I'm a radiologist. I work from home. This is my home office right here, so this is not like a skin or anything like that. So welcome to my office. And I know many of us are probably using ConeBMCT in our practices, either for dental and sleep medicine or for other purposes as well. And I just wanted to shed some light on how ConeBMCT can be used to evaluate for some risk factors for sleep-disordered breathing. And I want to just emphasize that really ConeBMCT is not the way that you would diagnose this condition or these conditions. It's a tool to help you reveal the anatomy of the patient that may be a risk factor for sleep-disordered breathing, but certainly not the end-all diagnosis for the condition. So whenever you see something on your ConeBMCTs with regards to the airway, there always has to be a clinical correlation. You can have a deviated septum and have no issues breathing through your nose. You can have a small airway and not have any symptoms of sleep-disordered breathing. So it's really about how this anatomy, these variations of anatomy or the presence of pathology can be related to the patient's symptoms. But if something is evident on ConeBMCT and there are no symptoms, we're not treating the radiographs, okay? We're treating the people attached to the radiographs if they have symptoms, okay? All right. So wonderful. So the way that we're going to approach this today is I'm going to show you two cases. I'm going to go through the scan. And I do have a chapter of my most recent book. Let me just pull up a book right here. It's specialty imaging, temperament, joint and sleep-disordered breathing. So this right here doubles as weights, right? And you can use it as a doorstop. You know, it's multi-use object, okay? All right. So the chapter I have is in PDF format. I'm going to show you some of the images from that. Unfortunately, I can't give it to you because it is copyrighted by the publisher. But at least it'll give you an idea what we're looking at. Okay. So why don't we start there? So I'm going to go through that chapter and the step-by-step look at this, okay? But before I do that, I just want to say that when an oral and maxillofacial radiologist approaches a combined CT, there are two parts of one's brain that work, okay? So there is the radiologist's brain, which is basically what a medical radiologist would do. We have a similar training in terms of the evaluation of the craniofacial complex, okay? So we go through it for pathology and other conditions just as a medical radiologist would. But then there's the second part of our brain, which is the dentist's brain, which comes from all those years of dental education, not to mention the continuing education that we do in all disciplines in dentistry, not one or the other, but all disciplines in dentistry, because we serve you, the dentist, who does all these procedures. So in my practice, I have orthodontists, I have TMJ specialists, I have dental sleep medicine specialists, implants, endo and impactions. So I have to know all this stuff, all right? So that is the two parts of your brain, okay? So now when I approach these combined CTs for dental sleep medicine, okay, for risk factors for sleep disordered breathing, I do all the stuff that I need to do as a radiologist first. I'm not going to go through this today because that's going to take actually more like a day or two, which is I have my own, I do teach how to read combined CT, but this is not what we're doing here. Today we're just going to focus in on the second part, which is thinking like a dentist and looking for those risk factors for sleep disordered breathing, okay? All right. So with that said, let me share my screen. I'm going to actually pull up the chapter first. So this is a chapter in that book that I just showed you, okay, Combined CT Analysis of the Upper Respiratory Tract, and it's got a lot of images here. So I'm just going to talk you through it first, so you understand what we're doing when we look at the patients that we're going to be doing, okay? So the first thing I do whenever I approach any case is I create a panel. A panel is like this happy place for all dentists, it's the thing that we're used to looking at and we can easily identify anatomy or at least some dental anatomy and what the teeth look like and, you know, the bone looks like in that panel spread, okay? But then, of course, I have to go through the scan appropriately so I can look at pathology in three dimensions, but the panel gives me this overview of what's going on, okay? I then create the T and J views, and there's a reason why I, you know, I named the book Temporomandibular Joint and Sleep Disorder Breathing. It was originally just Temporomandibular Joint, this is the second edition, and, you know, me and my mentor, David Hatcher, just felt like this was the natural progression for where we're going, a more holistic view of how the craniofacial complex is related to one another, okay? So I create the T and J views because there are clues in the T and Js that can lead to an understanding of why this person is presenting the way that they are, okay? And then I create 3D, and I look at the 3D to look at the face, look at the skeleton, look at how it looks like, and then I do volumetric measurements. Now the airway measurements are really not important to me. I put them in because dentists ask for them, but as I'll show you as we're going through the scan, really how many of these cases the airway can be manipulated through different, the size of the airway can be manipulated through different parameters, and I'll show you what they are in just a moment, okay? So when we go through the scan, we're going to start from the tip of the nose down to the hyoid. Now remember, this is just for sleep disordered breathing. We're going to go from the tip of the nose down to the hyoid, okay? And then, so in the nose, we'll have the external nasal valves and the internal nasal valves, okay? So that's the first thing we're going to look at, and in order to view these internal nasal valves, we have to create a specific cross section, okay, through that soft tissue area right outside the piriform aperture, which is the bony part of that skull of the nose. We want to be right outside it to be able to visualize these internal nasal valves, okay? We go a little bit further in. Now we're starting from coronal, okay, and we're moving back, right? In the coronal view, going backwards, we're going to enter into the nose, and we're going to look at the septum for deviations and spur formation of different types of deviations that may occur. And many times, these deviations come along with concha bullosa, which is a pneumatization. I just have to move down here a bit. Pneumatization of the middle nasal turbinates. Any of these turbinates can be pneumatized, okay? But the middle ones are the most commonly pneumatized ones, and when they enlarge, fill with air, they cram the nasal cavity. So if a person has a deviation to one side and the opposite concha is aerated, then there's a double whammy. They can't breathe from either side of their nose, okay? While I'm still in the coronal, I'm also looking at the transverse dimension of the nose, and I'm looking at the transverse dimension of the arches, because guess what? You know, the floor of the nasal cavity is the roof of the oral cavity. So many times when you have narrow arches, you'll also have a narrow nasal cavity. Not always, but most of the time, that is the case, okay? Because they develop together, and they develop narrow together, okay? Along with that comes also the depth of the palate, and this is all stuff we're still working through the coronal, okay? We're moving back now. Now, there are other structures that are better visualized on the other views, like the sagittal and the axial, but we're going to just stick with coronal. Make it easy, okay? So going back this way into the oropharynx to visualize the palatine tonsils, the enlargement of the palatine tonsils, the transverse dimension of that oropharynx, okay? And of course, there are different grades to that, which you probably all know, okay? So now we're done with that coronal evaluation. Now we're going to go to the sagittal view, okay? And in the sagittal view, some of the best things to visualize are the adenoids enlargement, okay? So how much of that nasopharynx is obstructed by the enlargement of the adenoids, okay? And keeping in mind that when we're looking at soft tissue in the nasopharynx, it's not always adenoids. Sometimes you have nasty things occurring in this area, like nasopharyngeal carcinomas that can erode the bony cortex here. So you need to be able to visualize not just the soft tissue and what it's doing to the lumen, but you need to look carefully at the cortical outlays that are adjacent to the soft tissue enlargement, okay? Now, while we're still in the sagittal, we also want to be looking at the lingual tonsils, okay? So we're looking here, we're looking at the lingual tonsils to see just how much of enlargement we've got. If we have a narrowing of the oropharynx at that level, we talk about that, right? We look at the soft palate, its length and its thickness, the longer and thicker the soft palate, the higher the risk for sleep disordered breathing. But keeping in mind that we do have some errors that can occur due to head posture, okay? So if you move your head forward, you increase airway dimensions, okay? So whatever measurement, whatever airway dimensions you think that you've got here, they're probably not true if the head is forward, okay? They're not representative of what's going on in natural head posture and certainly not what's happening during sleep, right? Okay, and then we've got of course the tongue posture, which when you move your tongue around in your mouth, it also changes the dimensions of your oropharynx and your soft palate can elevate as well, okay? If the patient is captured during mid-swallow, the soft palate elevates and that narrows the oropharynx as well, okay? So yeah, some other things that can narrow the oropharynx are the cervical spine. Not just the head posture, but also if you've got osteophytes, degenerative joint disease on the anterior aspect of the vertebra, pressing that soft tissue anteriorly, okay? That's like a double whammy if somebody has a narrow airway because of their small mandible, small maxilla, large tongue, whatever, as well as issues with the cervical spine, okay? And then we're going to move on to the axial evaluation, okay? So on the axial, there are a couple of things you look at. You look at the adenoids, okay? You look at the size of the oropharynx, okay? Just getting a sense of what you have. Now, if you can't create a volumetric measurement, you can create an area measurement, okay? And I'll show you how to do that in just a moment. But keep in mind that when you're going through the airway, it's important for you to look for asymmetry because asymmetry is no bueno, okay? If you see a soft tissue asymmetry in the airway, please take a closer look or send the patient to an oral surgeon to rule out the presence of squamous cell carcinoma in any of these tissues because that stuff happens, right? Okay, now we're done with coronal, sagittal, and axial. What we're going to do now is we're going to look at the shape of the face. And actually, I like to look at the shape of the face first before everything, you know? When I create my panel, my TMJs, and my surface rendering, I like to just get a sense of what's happening with this patient. How narrow is that patient? Does he or she have any exostoses that may indicate bruxism? Is that bruxism related to sleep disordered breathing, okay? So, right, so I'm going to talk about this in just a moment. Condular position, condular condition, as well as we go through the images, the scans that we are going to talk about, okay? So, yeah, so this is also the same patient that we're going to be showing, so that all is what we're going to be discussing, the role of the TMJ in the size of the airway, okay? Right, so anyway, and of course, we also look at the hyoid position, right? So, how far is the hyoid from the inferior border of the mandible, okay? And the lower it is, of course, that means that the floor of the mouth and the tongue are more inferiorly and posteriorly positioned, okay? And what we're looking for is something between 13 and 17 millimeters, anything more than 17, that's considered a low hyoid, like this is really low in comparison to the inferior border of the mandible, okay? And then come these airway dimensions, which I really don't like for many reasons. One is you can change the dimensions of your airway by moving your head forward to put your chin on a chin rest or to move your head back by strapping the head back, you know? The other is the airway dimensions change with inhales and exhales, right? So, like the different phases of your breath. In addition to the fact that when you have an apnea episode, are you awake or are you asleep and are you lying on your back or are you sitting upright? See, it's not really representative for what's happening when we actually have the issue. So, it's a parameter, it's there, but of course, the smaller the straw, the higher the risk, but in the end, we don't treat these numbers, we don't treat these volumes, we treat the person that's attached to them, okay? You can have a really large airway, but the collapsibility of that airway increases your risk for sleep disordered breathing, okay? And this is just something showing that the head posture changes. So, this is actually me. I sat in, a friend of mine has a Combium CT with a smaller sensor and didn't have the ability to move the chair, so she asked me to, well, first sit in natural head posture, which is what we have here. So, my face is cut off because the center is, you know, basically, I couldn't move in relation to the sensor without changing my neck, natural neck posture, right? So, here it is in the normal natural head posture. Now, the next one, she fixed me with a head strap, put my head back against the headrest, and you can see, like, within a couple of minutes, my airway dimensions changed, right? So, that's why I'm saying this is really not something to hang your hat on. It's a parameter, it's there, but we don't treat to these numbers, we don't watch them grow or whatever it is, it's just there, okay? And when we see a narrow one, a narrow airway, we think, okay, maybe, but then we have to verify that clinically, okay? Great, so now let's move on to the cases, and we're going to show a couple of cases. All right, so here's the first one, and this one is in a more pediatric patient, she's actually 17, okay, so closer to adulthood. But I want to talk about just looking at the whole picture, okay? So, the first thing that I do before I do anything at all is I need to make sure that the scan belongs to the patient, all right? So, you have to look, because sometimes the patient's name or with variations in the date of birth, whatever, just make sure that the scan belongs to the patient, that's the first and most important thing that you're going to do. The second is you have to orient the scan. Now, that's something that I already did with these cases for the purposes of looking at it as a radiologist, and I'm going to go through the scan from top to bottom to make sure there's no pathology, right? I check that box. Now, let's look at this for sleep-disordered breathing, okay? So, I mentioned to you that I like to create specific cross-sections, but whenever I get any case, all right, and those would be my pano, all right? So, I create the pano, and I make sure that my lines here, my dots are running along the arch of the jaws, okay, and I increase the focal trough just to get more bone into it, and then I'm going to create the pano, all right? So, I create the pano. Looking at the pano here, there are a couple things that stand out, other than the impacted teeth and the fact this person has ortho and all that, is the fact that the condyles are really small, and I feel like the mandibular planes are kind of steep, okay? So, that's something that I want to look at. I want to look at with a little bit more finesse. There's a lot of stuff here, but that's stuff that I would have weeded out already by the thinking like a radiologist part, okay? So, first, let's create the TMJ view, okay? It's in order to create the TMJ view on this software, I need to collimate it down to the area of interest, which is this right here, okay? That right there. And I'm going to create these cross-sections for other TMJs to make sure that these cross-sections run along the long axis of the TMJs and perpendicular to them, okay? so these cross sections now represent this condyle and its true medial lateral dimension, because notice how it's slanted, you can't really get it in the true coronal, or the true sagittal, you have to create an axially corrected cross section to in order to be able to to to visualize it okay. So here are the TMJ cross sections and the sagittal oblique and the coronal oblique and we can see a few things happening here let me get rid of these lines. We can see how small the condyles are, you see how small they are. Okay, they are small, but not only that, they're not small hypoplastic small they're, they're small in a different way. So one of the things that I look for in these condyles is the heights of contour the posterior height of contour and the anterior height of contour. Okay, so the posterior height of contour, normally in an adult condyle should be lower than the interior height of contour and we can see on both of these, it's actually higher than the interior height of contour if anyone's here has heard me talk about TMJ and idiopathic condylar resorption the degenerative joint disease. You know that the degenerative joint disease process is a biomechanical failure of soft tissue, which is the disc, followed by biomechanical failure of hard tissue, which is the bone, and that bone breaks down, and that phase is an active breakdown but then because this TMJ is such a miraculous structure and it's so important for our lives you know the continuation of our lives. And for us, for us to do the things that we do as humans you know speak and express ourselves, as well as, of course, eat and drink and all that stuff. Our TMJs have this miraculous ability to heal themselves. So, at the end stage of a degenerative joint disease process, they remodel. Okay, the remodel and the whatever, whatever shape they take is now the new norm. So when we see a condyle like this has these heights of contour which are at the same level and maybe the posterior height of contour is higher than the anterior height of contour that's telling us a story that's telling us that there's been soft tissue breakdown and then hard tissue breakdown and now it's remodeled, and it's created this new looking condyle but it's not by any means a normal looking condyle. Okay, this is end stage degenerative joint disease and because she's young she's 17 this most likely happened when she was younger so the term that we use for that it's idiopathic condylar resorption which I think is a terrible name for it. A proper name is juvenile degenerative joint disease. Okay, but what it goes by is idiopathic condylar resorption, ICR. Okay. Anyway, so where does all this all fit into the story. Okay, so with that bilateral condylar height loss. There is a generation of space between the condyle and the, and the fossa. Okay. And with that generation of space comes a situation of orthopedic instability. So with the orthopedic instability occurring that condyle tries to become orthopedic orthopedically stable and it sits into the fossa. And when it does that it rotates the mandible backwards. Okay, so we're about to see what that looks like on our volume rendering. Okay, so we'll create that volume rendering and we can see here, she's got a narrow arch. Yeah, her face is narrow. And if I turn it to the side you'll see exactly what I'm talking about in terms of a posterior rotation of the mandible, steep mandibular planes, anterior open bite, steep occlusal plane, all indicative of that posterior rotation of the mandible. Okay, so with that posterior rotation of the mandible because we've got all this, these muscles of the floor of the mouth and the tongue attaching to that mandible. There comes a posterior and inferior displacement of the tongue. All right. Now, that can narrow the oropharynx. Why don't we take a look and see what's going on with our airway. Okay, so we'll just do this volumetric thing. And like I said to you before, I really don't like these volumes. I mean, I will create the volumes for you. I will show you, you know, just where everything is. I'll talk, you know, if it's narrow I'll say the risk is increased. This is not the end-all and be-all. And this is, you know, when you look at Combio CT machines, vendors will talk about the airway, blah, blah. But really this is not what the evaluation is about. The evaluation is about that sequential analysis from the tip of the nose down to the hyoid lip, which is what I showed you in the chapter and which I'm going to show you right now. Okay, so here's the airway dimensions, not too bad. Let me just show you how unreliable these can be. Okay, so here we are. Look, it says 210 millimeters, you know, the smallest airway dimension, but look at this, look at this airway, whatever it is here, the algorithm is basically picking up soft tissue and identifying it as air. Okay, so when you are creating these airways, you are, you have to threshold your, you have to threshold where, what images or what voxels, what units, what grayscale units you want the software to pick up as air. So watch what happens if I increase the threshold. Oops. Well, that didn't work out. Let's go back here. All right. So watch what happens when I increase it just a little bit I will go overboard here. Okay, you get more, more voxels or more units picked up, more soft tissue picked up as air, whereas if I take it down like this, you know, and I threshold it, see it's starting to recede. And as I do this I just make sure that I try to adapt that volume to as much as I can to the actual outline and you can evaluate that on the, the actual as such. So you see how much less that minimum area dimensions become, it's still within normal limits. And if you are going to look at, if you're going to put numbers on this, anything below 120 would be increased airway, increased risk of sleep disorder breathing. 50 and below would be a higher risk of sleep disorder breathing. But in the end, it really you really don't know without looking at the patient clinically and getting a sleep study. Okay. So I showed you that limitation. Here's that airway analysis. Okay, so now let's go through this scan, as I mentioned, from the tip of the nose down to the hyoid. Okay, so we're going to start here. Okay. And we're going to start from the tip of the nose and many times these scans have the nose cut off. Okay, so if the edge of the scan is in the bone then you're not going to be able to pick up the internal nasal valves. Okay, so we'll go here. And we're going to create a custom cross section right outside and see, yep, we're right at that edge. Okay. And we can see how the internal nasal valve over here is a little narrow. Okay, even this one's a little narrow so there may be increased nasal resistance because of that. Right. So that's something that you want to rule out clinically. Of course, you look also are there other things in here that it might be narrowing that area. Is there a deviated septum? Was there trauma? Was there, is there a lot of mucus? You know, is there pathology? You know. All right, so we're going to go there and now I'm going to show you the coronal. So we're going to go into coronal and we're going to go to the front of the scan. So just adjust this. So we're moving all the way to the front of the scan here in the coronal. We already looked at the internal nasal valves out of slant, right? And now we're going to go into the nasal cavity, looking into the piriform aperture and evaluating what we see here. We see a deviated septum, like an S-shaped deviation. And we see a very narrow nasal cavity So this is not within normal limits. When you have your teeth in maximum intercuspation, you want your condyles to be seated, right? This right here is called a dual bite. So a dual bite is where you have two bites. You have the bite where the teeth are together and the bite where the condyles are seated. Okay, the term CRCO shift, it's pretty much the same thing, but I try to stay away from the term CR because I know some people are like, don't say that anymore, seated condylar position. Okay, so yeah, so I see an issue here. So let's start to investigate a little bit more. Let's create the volume rendering and I can see how narrow this patient is in the transverse dimension and the nasal cavity looks narrow as well. I'm gonna look at it with a little bit more finesse when I go through my scan, right? I see these little bulges. Okay, so why don't I take a look and create an actual surface rendering and visualize these bulges. Oh, look, exostosis all around and periodontal bone loss. All right, so when I see these changes, okay, we know that tori can be like the actual tori like palatine and mandibular tori can be genetic, but they can also be functional, right? So this may be a sign of increased function or hyperfunction, okay? So that's the kind of thing that goes ding, ding, ding. Is there bruxism going on here? Okay, all right. So we're done with that. We're gonna look at it from the side. Let me just turn it back to this view, turn it over to the side here. And we're gonna look at this and we're gonna look at the patient's face. We're gonna look at their jaw relations. And at first glance, when you look at this, you're like, okay, class one, let's move on. You know, class one angle that is. So, but then remember that the condyles are not seated in the fossum. Remember that the condyles are actually down and forward in the fossum. So this is actually a class two that's camouflaged. The condyles should be, if the condyles seat into the fossa, that mandible is gonna be more posteriorly positioned. All right, so good. So let's move on. You can do the airway analysis, as I said, not my favorite thing to do, but I will do it because it'll satisfy many people here and it will create that. And I just, I'm gonna go through that just to make sure that it's well adapted. It is, and wow, it is narrow, okay? So 32 millimeters square. And notice that it's 32 millimeters square, that air smallest area dimension is 32 millimeters square with the head forward. Look at the angulation of the neck. There's an increased forward head posture and that could be because of the chin rest, all right? But there's something here on this scan. And I know this because I've already seen the scan before. There's something here on this scan that I'm gonna look for to verify if this is the patient's natural head posture. If the forward head posture is true for this patient or is it because of the positioning in the COVID CT? And that is the degenerative changes, the adaptation changes that occur to the cervical spine with that forward head posture, okay? So as I scroll here, I'm going to just go around here and I can see some flattening and sclerosis over here. I see the narrowing of the intervertebral foramina on the side. The intervertebral disc spaces look like they're within normal limits. Let's look at the other side. Yes, that's narrow too, okay? So this is the actual patient's head posture, that forward head posture. And with that forward head posture comes a compression of those lateral masses as well as the spinous processes. Okay? So, all right. the patient has her natural head posture is forward, his or her, I can't remember if this is a man or a woman, is the natural head posture is forward. Now the question is, is this head posture a compensation to increase airway dimensions? It could be, but it's not doing a very good job, is it? Right? Okay. So these are all questions to be answered in the clinic, but these are some of the things that you see. All right. So now let's go into that actual airway analysis and I'm just going to delete this thing right here and go back here. So now we're going to sequentially go from the tip of the nose down to the hyoid. And the hyoid is not on the field of view. So we're just actually, we're just going to go as far as the scan is. Okay? So let's make this bigger. First thing we're going to do is create a custom cross section through the area of the internal nasal valves. Okay? Oh, I think I need to do it again. Okay. So I need to do this here in order for it to show up and here we go. Okay. So we can see that the nasal valves are patent. Okay. So no issues there in this area, this septal turbinate area, that looks like it's within normal limits. Okay. So now let's go into the coronal and sequentially go from the nose backwards, like from the piriform aperture backwards. And I'm just going to go all the way forward first here. Okay. And as I go backwards, here are the things I'm looking at. I'm looking at that nasal septum for any deviation or perforation or anything like that, spur formation. I'm looking at the transverse dimension of the nasal cavity, which I can identify as being narrow. Okay. I can see that there are no contrabalosa that I can identify. Right. I see the nasal passages and they look like they are patent. Okay. I'm looking at the nasal, the sinuses. Okay. So the sinuses here, there's a little bit of mucosal thickening. Let's take a look at the drainage pathway, which is this right here, the osteomental complex. That's patent. The drainage pathway here, that's patent. Okay. Now remember that it's all linked. All the sinuses and the nasal cavity, those are all biodynamically linked. Okay. So we're looking at this effloids as well. Okay. And if the frontal sinuses are on the scan, that's something that you do when you're looking for pathology in the first area. And then we have the sphenoid sinuses in this area. Okay. So in the coronal now, we're going to go down to the area of the oropharynx. Now you might notice that I can't get a real good view of the entire oropharynx. And that's partly because the head posture is forward. So what I'm going to do right now is I'm going to create a, I'm going to adjust this. I'm going to change the orientation. Okay. So I want this line or this oropharynx to line up with the coronal view, which is this blue line right here, which is what this view is. So what I'll do is I'll reorient it like that. I'll rotate it and I'll bring it to this level. And now I get a true sense of what's happening in that oropharynx along its entire length. Okay. It's a game of geometry here, guys. You just need to know what you're looking at and how to access it, how to best visualize it. Okay. And you can see how the oropharynx is narrow in this view. Okay. All right. So we're done with the coronal. Let's move on to the sagittal. On the sagittal, we're going to go over here. Let me get rid of these lines. Look at the nasopharynx, look for any adenoids. And this looks fine. You know, it doesn't look like it's obstructed or anything like that. Now we're going to look at the soft palate and we can measure it. It looks long and thick to me, but I'll just do this, you know, to verify that. Yeah, look at that, 46 millimeters. Let's see if I can find an air interface. That's probably it right there between the tongue and the soft palate. And I'm going to go kind of perpendicular to the length. And you can see that it's thick around 11 millimeters. Okay. So these are other risk factors for sleep disordered breathing. Let me get rid of all that. Now we're going to go into the area of the lingual tonsils. That's the epiglottis right here. Here's the follicular. And there's a little bit of enlargement, but it's not blocking that follicular. It's certainly not bulging into the oropharynx. The issues here lie in a couple of things in terms of oropharyngeal narrowing. One being the length and the thickness of the soft palate as well as the medial lateral dimension of the oropharynx, which could be because of tonsillar tissue. It could be due to accumulation of fat in the peripheral spaces. Okay. All right. And we see these exostoses as well. Okay. We already were able to visualize that on the 3D, but we can see them even here on the cross sections throughout. And on the axial, I'm just going to skip down to the mandible so you can see the tori. All right. So look how large these mandibular tori are. And look at these buccal exostoses, alveolar crosses exostoses. Okay. So here as well in here. Okay. Well, good. So once again, now through the axial, we're starting from the top, looking at the nasopharynx, making sure that there's nothing there. And we want to make sure that it's symmetric as we go through. Symmetrically, we can see it narrowing. We've already measured it out. You can do an area measurement if you want, but the most important thing that you're looking for here, once again, it's a cancer screening, is the asymmetry. Okay. Asymmetry of the soft tissue into the airway. Okay. Now keep in mind that some of the asymmetry can be due to a rotation of the cervical spine. Like right here, you can see, I think this is C2 or actually C3. And C3 is kind of rotated towards the right side. This is the patient's right. So that creates a little bit of a bulge forward. So just be sure not to mistake that for pathology, like soft tissue pathology, that it's just a displacement of the soft tissues due to the cervical spine position. And we take it all the way down to the bottom. There's the epiglottis right there. Like I said, the hyoid is not on the field of view, so I can't really measure it. Okay. Right. So what's the story of this patient? Let's put it all together. Okay. So this patient has a narrow airway. Surprise, surprise. And this patient is trying to breathe. So in order to increase airway dimensions, the patient has done a couple of things. First is the forward head posture. It's been a habitual forward head posture to increase airway dimensions. The other is mandibular advancement. Okay. So some patients, especially in kids who have large palatine tonsils, they'll move their mandible forward to increase airway dimensions. Okay. And if they do that over a long period of time, the teeth will super erupt and they will come into maximum intracuspation or something close to it with the condyles down the forward. So what we're seeing here are a couple of compensatory mechanisms to increase airway dimensions. Okay. Both the cervical spine and the mandibular position. Okay. The airway, the nasal cavity is narrow. The palate, I forgot to measure the palate. So why don't we go back to that? Yeah. So the palate is, I know it's narrow, but I'll go ahead and do it again here at the level of the first molars right here. I will do this here and here. Okay. We can see that it is narrow. Okay. About 32 millimeters. Okay. Right. So the face developed narrow. Now, why did it, I mean, the tongue didn't move back or anything like that. Not any way that I can tell, you know, but that's just the way the face is developed. It's developed narrow. And thus we see all these changes, not just in, you know, with that narrowness there, there's no space for the tongue and the tongue moves backwards. Okay. So that might be another possibility, another reason why we have a narrow oropharyngeal dimension. Okay. Okay. And of course these exostoses are, maybe there's some sleep ruxism happening here. Why don't we check that out? Okay. Once again, you don't come up with a diagnosis from the scan, diagnosis of sleep disorder, breathing from the scan, but if you look at the morphology, you look how this patient grew and you find these risk factors and you try to put the pieces of the puzzle together, of course, with the clinical presentation. Okay. All right. I had to turn on the lights. It's already dark here in Orlando. It's 8 p.m., almost 8 p.m. Okay. So let me see if there are any questions. I'm going to stop sharing for a second and let's see if there's- Thank you, Dr. Tamimi. Excellent presentation. Thank you. Excellent presentation. Okay. Before we take questions, if any audience member has a question for Dr. Tamimi and are using full screen mode, you will need to exit full screen mode to access the ask button to submit a question. I'll be asking the questions from the top down. So please make sure to use the upvote feature to move your favorite questions up the list. Also, in some instances, your question may be answered by a moderator in writing, in which case you'll see a notice under your question with the phrase, tap to see moderator's answer. Okay. So that being said, we'll go ahead and start with the questions. The first question, Dr. Tamimi, is how can one accurately measure the increase in the oropharynx space due to an oral appliance bringing the mandible forward and thus hit the ideal AHI? It's not about measurements. It's about that AHI. It's about how the patient improves clinically. Okay. So like I said, those airway dimensions, it's a malleable tube. It depends even on the phase of breath, whether the person swallows in the middle of the acquisition of the scan or even their head posture. Now let's say that you thought, okay, if that's really what you want to do, if you really, really want to do that and measure before and after, which I have my own way of thinking here. So I don't condone that, but the way that I see it is really the improvement in symptoms. But if you really, really want to do it, this is what you do. Okay. You have to make sure that you've normalized both scans to head posture, for head posture, tongue posture, and make sure the teeth are in maximum intercostal space in both, as well as make sure the patient doesn't swallow in the middle of the scan acquisition. Okay. So head posture has to be the same. Tongue posture has to be the same. All right. And what I normally tell people is like, just bring the tip of the tongue to the back of the front teeth. Okay. And just touch it lightly. Okay. To ask them to move it all the way up, some people can't do that because of tongue ties, you know? So this just brings it to a place of relative neutrality. It may not be the natural tongue posture, but the thing is, is if you ask people to come into natural tongue posture, the first time it might not be the same as the second time, right? So that's what I would say. Yeah. It's not about the numbers people, how many times do I have to say this? Thank you. Next question. Is there a standardized protocol for CBCT acquisition in patients suspected of having a sleep-related breathing disorder? A protocol. Okay. So standardized protocol. Okay. So what do you do in terms of putting the machine and what the size and all that? So I'm going to just talk about that. So first of all, this kind of an evaluation is not a high resolution, fine diagnostic task. Okay. So I'm going to talk like a radiologist who cares about radiation safety. You don't need a high resolution scan in order to do these. Okay. So first of all, you can get away with 0.4 millimeter voxels. Okay. You really don't need to go smaller than that, 0.35 max, you know, if you're really gonna be wanting a little bit more detail. And the reason is, once again, most of the stuff that you're looking at can be visualized at that larger voxel. The smaller the voxel, the more time it takes for the scan to be acquired, the more radiation it is. Okay. So let's put that, that's the resolution. Second thing is if you're looking at airway, you need to look at everything because that craniofacial complex is everything from here to here that's involved in that, in the, you know, in those risks, the presence of the risk factors basically are from here to here. Okay. So you need at least a 16 centimeter field of view. This doesn't cut it. Okay. This doesn't cut it. You need this. Okay. And then in terms of head posture, try to get natural head posture. If you can't get natural head posture because your positioning devices don't allow it, you know, it depends on the cone beam CT machine. Some machines have a chin rest and some have a head strap and some have head clamps and some have ear rods. There's just a whole bunch of things, ways that we stabilize patients in our machine. Okay. Whatever it is, the most important thing about acquiring the scan is that it has to be clean and crisp. Okay. And if it means putting a patient in a positioning device that changes natural head posture, that's okay. Okay. Because once again, I don't care about these numbers. All right. It's more about seeing the anatomy. If a patient moves, your scan is dead. You've irradiated them for no reason. Okay. It's a scan killer. Right. So if you put the patient in a chin cup, just keep in mind that that is most likely going to be a head posture. Most likely those airway dimensions are going to be increased from what natural head posture is. If that is not their natural head posture, if you push a patient back, you're going to be decreasing airway dimensions. And just keep that in mind. Okay. So if you can get natural head posture, fantastic. Let's make sure the patient's stable. Okay. That's the more important thing. Okay. Thank you. Okay. Next question. What medical billing code should be used when obtaining a CBCT for airway analysis? And would this differ from a TMJ CBCT? Gosh, I don't know the answer to that, honestly. That's okay. Yeah. You should, you know, you should ask the Nehrman group. I think they're, Rose Nehrman and John, I think they're going to look, they're on a mission to figure that one out. So- Absolutely. Okay. Next question. Does the presence of many nasal airway resistance factors reduce the likelihood of a good treatment outcome with a mandibular advancement device for OSA? I would say it depends. Okay. Now remember, I'm a radiologist. I don't see patients. So I don't see, I usually don't see afterwards. Okay. I think the answer to that is to figure out where the issue is coming from. Okay. So why does this person have this sleep disorder breathing issue? Okay. And you need to fix that issue. Okay. Not just like do the cookie cutter, let's put a, you know, MAD and that's it. Right. So you have to diagnose your patient. See, like, did you see how many facets there were to these patients' presentations who have issues? Yeah. So you need to diagnose your patient first and then deal with that issue to make sure that their treatment is successful. Okay. Okay. We'll take one more and then I think we're going to be out of time for tonight. When evaluating OSA patients already diagnosed by an MD, is it standard of care to order CBCT prior to initiating mandibular advancement device treatment? I don't think there's standard of care when it comes to this right now. It's prudent. It's prudent to understand where your patient's condition is coming from. But there are also clinical signs for these things. You know, you'd notice if someone's face is off, right? You'd notice if someone's asymmetric or if their mandible is retarded or they've got an anterior open bite or if they've got TMJ pain or whatever it is. These are all things that you look at clinically and then you make that call, right? If the patient can't breathe through the nose, you better know what's going on in there. You have to know that, you know, because it could be any of the things that I just showed you, but it could also be a nasty tumor, right? And that's rare. But you need to know why this person can't breathe through their nose. Perfect. Thank you. I think that's all the time that we have this evening. Dr. Tamimi, I'd like to thank you so much for your participation tonight. We appreciate all your generosity and participating in the webinar. And thank you to all the attendees for joining us.

CBCT

sleep-disordered breathing

anatomy

risk factor

diagnostic tool

nasal septum

palatine tonsils

lingual tonsils

clinical symptoms

obstructive sleep apnea