 What we can do now is open it up for questions. We have a question here. Thank you for the compliment. My question is about liposcarose and mix-up fibrous tumors and overlap of the annihilation. So LSMFT, liposcarose and mix-up fibrous tumor, we didn't show in this case, but it basically loves the proximal femur on the femoral neck. Typically you'll see a lesion that may or may not have fat, it might have microscopic fat, it might have some cysts in it, it might be sclerotic. And that can look like other lesions. I mean, it is thought to be, I think, a borderline. It can be a benign, but it might be malignant. I think it's controversial. It's not certainly a malignant lesion, but if you just had fibrous dysplasia or lipoma with cystic degeneration, that could also have a similar appearance there as well. And let's see here. What are the questions you guys have? Hopefully you guys feel like now, if you didn't, that you also, that you have kind of a better way to kind of just face an unknown lesion. So remember that you want to look if it's lucid or sclerotic, is it well-defined or ill-defined, and then just kind of put in your differential diagnosis of some of those lesions that we talked about. We have a question here. How to differentiate between chondroma and periosteo, osteosarcoma? So you have these entities known as surface osteosarcomas, which are par-osteo-PAR, which is usually a very, very dense thorodic lesion and peri-osteosarcoma. And so that is, it is hard. Those are, they have a different appearance. Osteosarcoma will typically have more of an aggressive appearance, more of a more malignant, more of a soft tissue mass. Chondromas, you'll have that lobular, micro-lobulated appearance. And when you give contrast, they might have kind of a rim enhancement, sort of punctate areas of enhancement different than you might see with more of a solid enhancing tumor in an osteosarcoma. Are there specific radiography features of B-core sarcomas? Wow, you guys are super advanced. There probably are. I'm not totally sure if there are specific that I know of, but I have heard of that. And I know that's like a pathologic distinction on some of the large lesions, like ABC-Howard diagnosis is being made, are they receptive for diagnosis? What happens to the remaining mode? Is it butchered? Okay. So ABCs, androsylbonesis, they are going to get worse and worse and get bigger over time. And you need to treat that. The typical treatment was surgical curatage and bone graft. Now there's some newer exciting treatments. Our IR guys here are doing really, really exciting things. My partner, Shankar Rajaswaran, is doing really exciting things with these cysts. He is going in there and he is doing basically sclerosis, grafting and even cryoablation of these lesions or minimally-based techniques. And so there's some newer things coming out. What about myeloproliferative disease and bone marrow changes? What to look up? So for example, if you are talking about malignant, diffuse malignant processing such as leukemia, for example, is one that I think is important to know what that looks like. You're going to see a diffuse marrow replacement. So the whole marrow will be very, very T2 hyper intense and dark on T1 for those cases. Does that answer the question there? In the intraarticular osteosteistomy case, can we differentiate osteomus with sequestration? Very good question. So sequestration, which is a small bit of sclerotic bone, dead bone, which can serve as a nitrous for infection. You're actually right. That could look similarly to an osteosteoma. You probably would have a history of osteomyelitis that was refractory to treatment and then you will follow the MR and you find that, but you're right, that could look similar. Usually it's more of just a dense sclerotic white piece, not like a beautiful round area of anitis, but you're right, that could look similar. And in this case, they did a cryoablation, they biopsied it and they also then cryoed it and there were no other, some patients were approved right away. Can you explain case number 15 again? Yes, let's go back to that. So for case 15, this is a hard case. We see two lesions. One lesion is here. And if I just saw this, I would say that there is an ill-defined, lucent lesion and I'd be concerned, hearing myself say ill-defined, lucent lesion in the pelvis, I'd be concerned this was a malignant lesion such as ewing sarcoma, which can occur in the pelvis. Yet, when I look at this other lesion, this is a lucent lesion, which has a well-defined margin and it has a sclerotic rim. That actually looks more benign. So you do have to give it our differential diagnosis for this case. So this could be ewing sarcoma with a metastasis to the pelvis. However, I think it's important for us to give a differential diagnosis. It was a young child, family was very worried and they just asked, is there anything that this could else be? Could this be something benign? And that's when I said, well, it actually could be LCH. And so that's what it was. So it's good to have a differential diagnosis. Then there's a question here. Sorry, there's a question. Prognosis of osteoporosis plasia. So osteoporosis plasia, basically it's fibrosus plasia. And if it's truly not a adamantinoma, it's a benign lesion and it may just kind of get better. They may have to, if it has a pathologic fracture, they may have to treat that. They may have to stabilize the bone, but it is a benign. And then what about the right SI joint, especially the ilium? I assume talking about the other case. Yes, it does look a little sterotic here. Is that maybe what you were worried about? In this case, I think it might just be some overlapping stool. I don't remember the case exactly, but don't worry about that there. Stress fractures in plain X-ray. So stress fractures. If you have just a early stress fracture, you may not see anything on X-ray. As we know, the MRI will show the edema whereas X-ray could look normal. However, as we have a healing stress fracture, you're going to see the periosteum new bone and you're going to sometimes see a little loosened fracture clapped buried in the cortex. So if you see periosteum reaction and thickening, that's what a stress fracture would look like. When, let's see here, best book for bone tumors. Good question. I don't know the answer to that. And I don't want to, I don't know. There's many good things out there. Let's see here, when should we consider METs in pediatric X-rays and which all primary sugar level first? So if you see METs, so the thing in pediatrics is that it's not as common as in adults. In adults when you see bone lesions, you always throw in METs for the diagnosis. In pediatrics, neuroblastoma, which is very, very young children will go to bones. That's what we want to think about. Neuroblastoma is a big one. So that would be a primary to realize neuroblastoma. Please explain evulsive cortical irregularities. So evulsive cortical irregularities, I think of it as just the origin of the gastroc tendon is basically pulling on the back of the femoral cortex. So it just causes kind of a little bit of a regularity and a little bit of like bone breakdown. So it can produce this lucid lesion. That's why it's just called evulsive cortical irregularity. Just a name is saying what it's doing. Sight of unicameral bones, is can it be in the epiphysis? What is there in case five, in case 14? It can be in the epiphysis that is possible. It's not as common. So in case 14, you're right. You could include this in a differential diagnosis. When you do MRI though, a cyst will have central non-enhancement, just rim enhancement, whereas a condroblastoma would actually be solid enhancement. Case five is basically a lucid lesion with a sclerotic rim. And this is basically a more common location for unicameral bones in the meta-diaphysis. Is there a lesion in case two proximal fibula? Yes, there is a lesion in case two, very good. This is another non-assifying fibroma, very, very good. Guys are excellent. You guys are awesome. You don't need my help, but hopefully you guys feel more comfortable about approaching bone lesions, which bone lesion do you need to know? Are you related to possibly to send out my high school classmate, Carol Simmons, a cellist, I think, class of 1967, St. Louis, Missouri. Sorry, I am not. I am from Baltimore, Maryland. Not that I know of. Net NOF versus FCD. Is that focal cartilaginous dysplasia, I assume? Focal cartilaginous dysplasia is a rare entity that we typically see in the proximal tibia or distal radius. And it looks like a weird notch or concavity in the bone, whereas NOF is a lesion that is kind of filling the bone if that is the question you're asking. How to differentiate chondromic fibroma and end-chondroma lesion in the distal tibial metathesis forgot the case number. So chondromic fibroma is a lesion that can also look locally aggressive. It can be a loose and lesion. It is not as common as end-chondroma and chondroma is much more common. End-chondromas love the fingers, so that would be more common. You may not be able to differentiate those as well. I actually had a case once that I presented at a meeting of chondromic fibroma of the toe, and you're right, it could look similar, but common things being common, chondroma more common. Appearance of chondroma on MRI, please. So we showed a case of a chondroma and basically it is a lobular T2 hyperintense lesion, which is typical for a chondroid lesion. And what you can see here is that it has these like kind of micro-lobulated margins that is very characteristic. And if it is sitting on a cortex, then you think of periosteocontrolum. What is the indication for MRI? Can we diagnose most of them by playing X-ray? Good question. We love to have X-ray first. X-ray can diagnose many of these lesions. I think MRI, traditionally people used to say MRI is only for staging of disease, not for diagnosis of lesion. I don't totally agree with that. I actually think MRI is really helpful to distinguish solid versus cystic. As you saw in a lot of the cases and prior questions, some of these lucent lesions, you're not sure if it's cystic or solid. So is it a chondroblastoma or is it a unicornobonesis? Well, when you do an MRI with contrast, you can see that a cyst will have rim enhancement and the chondroblastoma will have solid enhancement. So that's when I would do MRI. And also if you have a lesion on X-ray and it doesn't fit into a benign category and you don't know what it is, that is an indication for MRI. I think as a radiologist, if you see a lesion, it's not something that you can neatly put into a benign category. I think you should do an MRI and I don't think you should let it go. 82 questions answered. I'm firing off the answers. Keep them coming. You got any more questions? Hey, so, oh, there it is. One more question. Typical location for chondroma. I assume you're referring to periostial or juxtacortical chondroma. I've seen them in the humorous. I've seen them in the proximal tibia and in the tibial tubercle, but I'd have to look up to see a distribution if I was going to give you an exact answer. All right, I think you answered everybody's questions. Oh, one more just came in. Dr. Samet. Rads in children. I'm not sure what the question is, is that referring to, is there like an O-Rads, like a system to kind of help define, help you put things due to great lesions? Not that I know of, I know that O-Rads is kind of coming up for adult lesions, but not that I know of for pediatrics specifically. How to tell apart between chondroblastoma and giant septum rebone. Good question. So remember that kind of think that 20 years old is a cutoff. We don't really see giant septum rebone below 20. So if the growth plates are open, you pretty much never see giant septum rebone. And so you can use kind of that to help you. Chondroblastoma bone usually is in the epiphysis. Giant septum rebone is in the epiphysis, but it actually is in the metaphysis and the epiphysis. And so when we very, very rarely see them in pediatrics, it actually is in the metaphysis. And that's why people think they originate from there. So I would think 20 years old is kind of a good number to differentiate those.