 and welcome to Noon Conference hosted by MRI online. Noon Conference connects the global radiology community through free live educational webinars that are accessible for all and is an opportunity to learn alongside top radiologists from around the world. We encourage you to ask questions and share ideas to help the community learn and grow. You can access the recording of today's conference and previous Noon Conferences by creating a free MRI online account. You can also sign up for a free trial of our premium membership to get access to hundreds of case-based micro-learning courses across all key radiology subspecialties. Today we are honored to welcome Dr. Majid Khan for a lecture on advanced spine imaging. Dr. Khan completed his radiology residency at NUMC Stony Brook University and subspecialty training in neuroradiology at Johns Hopkins University. He is at present on the neuroradiology and interventional radiology staff at Johns Hopkins University. Dr. Khan is a nationally and internationally recognized expert in spine tumor ablation and spine cement augmentation procedures. He has published extensively on these areas and has been invited to lecture, preside over panels, run workshops, and moderate sessions on many national and international conferences. At the end of the lecture, please join Dr. Khan in a Q&A session where he will address questions you may have on today's topic. Please remember to use the Q&A feature to submit your questions so we can get to as many as before our time is up. With that, we are ready to begin today's lecture. Dr. Khan, please take it from here. Thank you so much for that introduction and let's start our talk today. So we'll be talking today about advanced spine imaging and how this is helping triaging patients for better care as well as better prognosis, treatment prognosis. Okay, these are my disclosures. So we know that vertebral compression fractures are basically benign and pathological. From the benign group osteoporotic compression fractures are the main reason for the fractures and constitute about 25% in the postmenoprazole women. Trauma is a very common etiology, especially in people less than 50 years of age. And then finally, we have these pathological compression fractures with the usual culprit cancers metastizing to the bone and causing compression fractures. So evaluation of these compression fractures diagnostically, most of the time, doesn't need any diagnostic challenge. But sometimes in few cases, you will see as I get this talk that there are times when normal anatomical imaging, which is the backbone of imaging doesn't really help and you need to go to these advanced imaging techniques to answer some of the questions that are being posed, especially by the clinical colleagues. You can have primary bone tumors such as myelomas and lymphomas, they can also give rise to these compression fractures. Statement of benign and malignant compression fractures as we know is very, very different and hence it's very important that diagnostically we make the distinction between the two. Most of the, as I said, most of the time, it's pretty easy to make the distinction, but sometimes it has become harder, especially in elderly patients where you have significantly degenerative changes and all the signal changes and density changes that happen on CT and MRI. The imaging modalities that we have available to us range from X-rays all the way to CTs, PET CT, bone scans, as well as MR imaging, which is probably the main state of imaging. I am not advocating that advanced imaging techniques should be used for every case of spinal compression fractures and there are specific indications where these modalities help. We're talking mainly about the diffusion as well as the profusion imaging and we'll touch on the chemical shift as well as some PET scan images that I'll show you for this. Overall spinal metastasis, a bone metastasis is the third most common site after lung and liver and the bone met spine is the most common site of metastasis. 28,000 new cases of spinal metastasis happen in the US every year and about 15 to 20 percent of patients with new cancer diagnosis so that means stage 4 disease to begin with you see involvement of the spine. So this is a case example here. This is a patient of mine who fell down from a bar stool. She was in her early 60s so had a fall and you can see that there is a mild compression deformity that is involving the inferior end plate of this vertebra. She had pain which wasn't really was probably about four or five out of ten and so she was put on conservative management and she was put on our TLSO brace for about six weeks. This is the MRI on the patient. You can see that there is not much of stern oedema there maybe a little bit along that inferior end plate. There is some retropulsion which is deforming the tical sag but there's no significant compression or anything. So the patient was put on this conservative management. Her pain did not improve at all and in fact was gradually worsening over time and that's when the patient was referred to me for treatment and we ended up putting a spinal implant in her as you can see here. So we do I really do not throw my biopsy specimens away so I took the biopsy and sent it out to the path. So even after this procedure the patient was continuing to have some pain. Most of the time patients were after augmentation feel pretty good after the procedure but she continued to have a good bit of pain and that was really surprising to me and when the biopsy came back it was lymphoplasmocytic leukemia and going back to the anatomical imaging if we look at her T1 weighted image we do see that there is infiltration of the marrow signal and we are losing our normal T1 signal that we should be seeing in the bone and that was a clue that something is going on. So she had a marrow infiltrating disorder and she went on and got treated for her lymphoma and her pain improved quite a bit. So this is just incidentally found and over the years that I have been in practice I have at least six or seven examples of this where we incidentally ended up finding cancers when we did not suspect on diagnostic anatomical imaging. Now this is another patient. This is a patient with renal cell carcinoma. Of course there is infiltration of this vertebra. There is some enhancement post-contrast that is posterior cortical bulge that you can see here so and patient was in pain. So patient was treated with SBRT and post SBRT you can see here that the patient developed a fracture. So when this patient was presented in our tumor board this question that was specifically asked was hey is this now residual cancer that has caused this fracture or this is a post SBRT fracture. For those of you who are not familiar with SBRT multiple papers have come out that stereotactic bone radiation is associated with an increased incidence of post-radiation fractures. The initial papers that came out of Sloan-Catring put the incidence about 40 percent. Our paper that came out a couple of years ago we were around 25 percent. Now most of the radiation oncology guys they have decreased the dose and increased the fractions and realistically I feel right now we are somewhere around 15 to 20 percent range with post SBRT spinal fractures. That's also pretty high almost almost one to one in four. So but going back to the question that was asked of me it's really hard to answer this question on anatomical imaging. It could be from tumor it could be from SBRT. I really could not answer the question based on anatomical imaging but fortunately by this time we were doing our advanced imaging technique which we'll talk about in a little bit and by doing so I was pretty sure that this was cancer related fracture and ended up biopsying this. The biopsy did prove that there was there was still tumor viable tumor in this vertebral body. So if you look at the literature let's let's first look at the anatomical imaging and what are the characteristic features of fractures benign versus pathological fractures on on routine anatomical imaging. So abnormal marrow infiltrating the pedicles is a very strong indicator of malignancy in the compression fracture world. osteoporosis infrequently involves the posterior elements as we as we know but it may involve such tumors spread to the posterior elements typically occurs because the tumor associated structural instability leads to the fracture within the vertebral body. So here's an example this is a patient who had both a pathological as well as a benign fracture and here you can see the distinction very clearly here you have infiltration of the marrow signal there is some extension into the pedicles at that level this was a pathological fracture while as this was a benign osteoporotic fracture where you have retention of your normal signal and then of course there is enhancement at that level. As I said as with everything else in in radiology there's always a pitfall so acute osteoporotic fractures sometimes may have altered signal or may have some enhancement that extends to involve the pedicles and and likely it is due to some inflammation or a stress reaction that happens in the pedicle or the pedicle also has an occult fracture in it leading to those signal changes so you have to be very careful about what all malignal fractures will have extension of the infiltrative process into the posterior elements that many a times we have just seen involvement of the body with normal appearing posterior elements especially the pedicles. So this is one such example this is a patient with a benign compression fracture post trauma and and you can see that the signal changes are extending into the pedicles bilaterally but this was a benign fracture and you can see even see a cleft sign in this fracture which is a sign of benignity. So when you have a posterior pedispinal mass that is a short short sign of a surgical compression fracture with associated mass and no one here in the group would ever think of calling this a benign fracture with such plurid involvement of the posterior pedispinal soft tissues epidural entrolateral masses so this is this is a clear card sign of a pathological fracture when you see it. Usually when it is very subtle you will have a bi-load of the parents of involvement epidural space because the sagittal septum in the midline pushes the epidural extension of the tumor to one or the other side so that's a fairly characteristic appearance that you see in the ventral epidural space with tumors. Sometimes pathological I mean benign fractures can have a bit of hemorrhage around it and can have an entrolateral hemorrhage which gives the appearance of soft tissue prominence. Here you can see this is a cortical break and you have some soft tissue prominence but really this this doesn't really is not hard to differentiate from a pathological soft tissue mass. On tour of the posterior cortex should always be looked at normally you will have a very smooth posterior bulge of the posterior cortex and that when you have such a smooth convex bulging that is that is suggestive of a pathological compression fracture because the tumor infiltrates the marrow cavity the spongy bone and the axial load actually causes the bulging of the posterior cortex so make use of that that sign very rarely benign osteoporotic fractures can also have posterior bulging but most of the time if it is a benign fracture you will have bulging of the superior aspect of the posterior cortex inferior aspect of the posterior cortex or you can have an incomplete slash complete burst fracture with that puzzle sign that we see so this is this is how an incomplete burst fracture will look you will not have that smooth posterior convex bulge of the posterior cortex here you can see the superior aspect is bulging more than the inferior aspect and this is an incomplete burst where the fracture fragments are pushing very typical of a post-traumatic or a benign compression fracture in the spine this is the mr equivalent of the fractures that we just discussed again you do not have that smooth bulge you do not have infiltration of the marrow that you expect to see with that bulge in a pathological compression fracture you have normal retained marrow with with just a focal retropulsion of a fragment there just an example that very rarely you can have a benign fracture that can have a very smooth convex bulge so that is pitfall again that can be seen with some benign fractures this is a patient of mine they had a fall and had some neck pain upper back pain had history of breast cancer which was diagnosed about 15 years ago she was in complete remission at a fall so everybody was thinking that this is probably a fall related fracture of course we have a convex bulge they are very smooth we have some soft tissue prominence in the epidural spate both ventrally as well as dorsally so that's a red flag right there and as you can see on this post images that there is a dominant epidural mass of the post contrast ventrally and dorsally so this was actually a pathological compression fracture rather than a benign compression fracture like years and years later in a patient with breast cancer a lot has been said about the location and the multiplicity of fracture in a patient but really it is of a limited clinical utility many not many studies have been done to say that if you have multiple fractures you are dealing more with benign fractures versus pathological fractures yes patients with severe osteocorosis can have multiple fractures up and down their spine but so can a patient with multiple myeloma so so really can't hang your hat presence of these multiple fractures throughout the spine signal changes and enhancement pattern of course we know that there is in the malignancies and infiltrator process which replaces the normal T1 bone signal and causes a low T1 signal so when we are evaluating bone that's the T1 weighted image is our friend and that's what we are looking for if any there's any alteration in a normal high T1 signal of the bone we start to think about many other many processes that can involve the bone in comparison osteoporosis is due to decrease in the density of the bone and hence there is collapse of the vertebra much more earlier than the infiltrative signal so and it's not an infiltrative process and hence even though the vertebral body is collapsed to a moderate extent you will still see normal appearing bone marrow signal in a benign fracture and and that's it's a very good and easy sign to see on MRI of the spine when you have a is big use of that and this is just an example this is a T1 weighted image you can see that there is loss of the normal T1 signal the the bone is darker than the adjacent disc we know that is not normal so this is a very diffusely infiltrative process that is involving the spine in this patient T2 is also dark in this patient and of course when we go to CT we see that the patient is riddled with osteoblastic metastasis up and down her visualized spine just an example here we have a patient where there is some heterogeneous T1 signal T2 signal and then a focal area of decreased T1 T2 signal and even stir signal is decreased here while as in the lower level basis these signals so this is a hemangioma and this is likely a blasted metastasis on CT there are ways how you differentiate between a blasted metastasis versus say for example a bone island a couple of good papers have come up on that and you really on CT you measure the density and usually metastasis is lower than that of bone island the bone island is typically over thousand ounce field units while as metastasis are typically under a thousand ounce field unit anywhere between 800 to 1000 so that's one way of differentiating and the other way is margins if you have more speculated margins you tend to think about bone island rather than smooth margins you tend to think about metastatic disease but not many papers are out there trying to differentiate between the two but those two numbers that are margins as well as the ounce field unit are two important characteristics that we use especially on CT to differentiate blasted metastasis from bone island so this was a patient with blasted metastasis right here and this was a straightforward hemangioma that was bright on all sequences so far so good it's easy on anatomical imaging these are relatively easy cases and we are able to differentiate benign versus malignant compression deformities or lesions in the spine this is another example of a patient who has almost moderate compression fracture deformity I do see retention of my normal T1 signal so that's a very good sign for me to say that this is more likely to be a benign compression fracture than a malignant compression fracture and it turned out to be a hematopoietic fracture another good thing when it comes to compression fractures of the spine is to note for the cleft sign or the air cleft sign within the vertebral body this is almost always a sign of benign fracture and whenever I see it even in patients with cancer I tend to favor a benign etiology rather than a pathological fracture so make use of this sign when you see it and it's actually a DEMA that DEMA flow jet just collects in a cleft rather than the whole vertebra showing you the bright stir signal from from a DEMA this is the CT equivalent of the cleft sign where you can take a take a pen and you can draw a line and you can say that there is more superiorly inferiorly everything looks pretty good so it's not it's a very narrow zone of transition right rather than the wide zone of transition that you expect to see in more pathological fractures you can see the air cleft again that's that's a sign of benignity and whenever you see it this is this is osteonectrosis the importance of this is that this has to be taken care of because more often than not patient will end up developing a severe compression fracture within next few weeks or if this is not taken care of especially if they're having pain this is kind of sort of an indication to me that this has to be taken care of relatively as I said that there is always some pitfall in radiology you never say never so this is one patient of mine that I had where you can see almost a cleft sign here yes there is a fracture patient had remote history of cancer and they wanted me to biopsy this just because there was just because there was history of cancer so I was very very reluctant to biopsy this case but then I saw this that there is some better spinal fluid also I said this may be just some infection rather than tumor so I ended up biopsying so I biopsied FNA that fluid collection that was in the interior better spinal region as well as ended up biopsying the bone and it was really very humbling of course it turned out to be nothing but the bone biopsy turned out to be a metastatic edema carcinoma so even after this I'm not advocating that hey you should be whenever you see a cleft sign you should be thinking about this case of mine I still say that this is the cleft sign the air sign is a sign of benignity and should be kept as such although we do have a few case examples of where actually it was moving okay so far so good as I said that was relatively easy now moving on to some of the cases where advanced imaging actually made a difference so diffusion made in images in a patient with benign osteoporotic fracture we have bone edema hence more water content is there and so you will have more facilitated diffusion in such a patient as opposed to patients with malignant compression fractures you actually have infiltration of the marrow with soft tissue and hence you will have a decrease or a restricted diffusion with a decrease in the ADC value so that's the premise of diffusion made in images as we know as we apply brain or any other part of the body is the source the same application happens in the osseous spine also so these are these are really the indications for getting diffusion images in your spine and now we are doing it for marrow pathologies also in some select cases it really does add or improves the detectability of the osseous metastatic lesion compared to conventional imaging at times so what really got me to do this type of imaging is this case initially that I had years and years ago in which a patient was diagnosed with lung cancer as you can see and then there was a focal spinal metastasis as you can see here so this tumor was removed the patient developed had SBRT for her spine involvement and this is the follow-up spine you can see some very mild superior end plate remedy there but overall single is well maintained patient didn't have much pain this was a four month follow-up after radiation and after surgeon patient was doing well this is the same patient one year later you may say now there is slightly more progression of theirs there may be some progression looks pretty good patient was having four out of 10 pain not not bad at all was was some leave was helping with pain and that was about it and the patient was completely functional and active but then about a year and a half patient suddenly developed a new onset back pain and when we put the patient for imaging this is what we get so now definitely there are compression fractures here there's a focal area of stir signal in this vertebral body and these two obviously are fractured so again when the the case was presented in the tumor board this is what was asked hey is this benign or do you think that there is some tumor out there and it's it's related to tumor involvement so this is your pre-contrast this is your post-contrast this is t2's and all that and we really don't like to see dark t1 and bright t2 and then enhancement post-contrast so it's really hard to say whether this is benign or tumor related so back in the day we did not do any advanced imaging so we ended up biopsying all three levels and all three levels came out to be negative for tumor but that that really got me thinking that we should be doing a better job at diagnostic imaging in such cases and not going straight for biopsies and if we did have diffusion imaging back then it would have really helped so we started to do the diffusion vented images we did it in multiple straightforward cases because there's a learning curve and you we were learning the text we're learning how to get the diffusion vented images in Ossias spine because mostly people weren't doing it for quad so it took us some time to get to an optimal b-value that is needed for Ossias spine because it's different from from soft tissue b-values so we are right now we're probably around 800 b-value that we are comfortable with in our Ossias spine world so here you can see it's a straightforward case but you can see very nicely the diffusion restriction in that in that in that vertebra and of course this was this was no brain after that this is not a normal appearing vertebra and we started to quantitate we we started to put look at the numbers because we were ending up biopsying most of these vertebras anyway so we were trying to gauge like what numbers we are very comfortable with calling pathologic versus numbers where we are we're not as as as comfortable calling normal so so we're playing a lot with these numbers and all that so this is a this is another straightforward case you can see but diffusion ADC very nicely this is this is a good example that i'm showing here here we know that this is an abnormal case obviously there is probably a lesion here probably maybe lesions here and there on routine anatomical imaging but when we do you do the diffusion either the the lesions are looking at you rather than you looking diffusion imaging while as here you would have said maybe this is one this is another this is third this is a patient again with breast cancer and complained of neck pain and routine imaging that was done demonstrated this mild loss of height of this c7 vertebra with some subtle t1 hypo intense and t2 hyper intense signals so again the question was is this is this somebody generative changes this a fracture is this a met in the vertebra so we ended up doing diffusion diffusion did not show anything so I was pretty comfortable in saying that hey this is this is nothing they ended up doing a PET scan and the PET scan showed nothing we did not biopsied this this patient then bb2 eb so that this was going to be actually previously if we did not have all this we might have gone in and biopsied to prove that there is nothing so you can do as in the brain you can do qualitative as well as quantitative assessment of the diffusion slash adc values many papers have come up actually trying to get a value on multiple other sequences and comparing it to the diffusion weighted image just to optimize the sequences and find out the numbers that people are comfortable with because speaking about spine diffusion it's something relatively new it's we are still we're still playing with the numbers when it comes to spine diffusion immediately it's not as robust as for example in the brain tumor world where we know what is what based on the adc quantitative values so the tumor that has been probably most studied in the in the spine diffusion world is cordoma and uh we with cordoma is anything over 1500 adc is is we comfort we are comfortable in 15 1600 we are comfortable in calling it more towards the main end of the spectrum anything that is below 1200 ish 1100 ish that is definitely the abnormal end of the spectrum so it's it's the number between this 11 1200 to 15 1600s that we still don't have a good handle on and so that's one of the reasons we are doing these imaging techniques we're probably getting these adc numbers and then making a call and then finally ending up biop seeing those patients and and finding out which number we are comfortable with especially in this intermediate slash transition zone so adc value around in about 1800 for sure is a sign of benignity on the bone world and obviously anything under 800 is is is malignant i'll go up and i'll i'm now if i'm seeing anything around 1100 ish also i'm not comfortable in in calling that uh that it's uh it's it's clear so even around 11 1200 i am more towards uh the sinister etiology uh so so but now i'm i'm comfortable 1200 and below is malignant 15 1600 and above is more benign but we're still struggling with that in between numbers so now let's go to some of the cases where actually the advanced imaging techniques really made it different so this is a patient with again remote history of breast cancer we have a t1 which is dark we have a t2 which is bright and there was some subtle enhancement after contrast administration i should have put up that i'm sorry so what do we think now is this malignant is this just a benign lesion say a typical hemangium very hard to say if that question is posed to you that hey what do you what do you say is this benign or this is malignant absolutely i won't be able to answer that question right away so in our diffusion and this and you can see the adc is really really bright on this so this is facilitated diffusion so after this i was i was pretty comfortable in saying that this is actually a benign lesion maybe an atypical hemangioma and that's exactly what it turned out to be it was a nonspecific biopsy and so it was an atypical hemangioma in this patient uh this is another patient with history of lung cancer obviously there it's was treated by external beam radiation because of the extensive disease involvement now was complaining of severe pain in the lower back which was related to this lesion that is involving the l3 vertebra so it's benign or is this malignant again very hard to distinguish uh that looks like there's a schmottles note there and could be could be benign but really you can't come out very hard and say that this is a schmottles note and nothing else so we ended up doing our diffusion again adc was quite dark and the biopsy showed no tumor in that region not only in the making the diagnosis in some select cases but prognostically also it is making a huge difference for our medical oncologists as well as our radiation oncologists and this is one great example of such a case so this is a 46 year with myloma you have a focal lesion that is involving the iliac bone it is enhancing and this is your diffusion and this is your adc so it's dark on adc it's an active lesion and so the patient was treated appropriately for for for myloma and then the follow-up scan which was done almost three months later so this is the post-contrast imaging so if you were just reading an anatomical imaging you would be saying that the lesion is pretty much the same or may have actually worsened a bit based on these two scans but look what is happening on diffusion in adc the adc is actually facilitated so you can go out and tell your uh colleagues that the whatever they are doing is actually helping the patient and and you see a distinct change in in in the infiltrative manner of this lesion and it's doing much much better so so from saying it's the same or slightly worse and now you're saying that hey whatever you're doing is really really good so that that that makes a big difference in treatment planning it has helped me glide biopsies at times so this is another patient with two lesions so one is in the five vertebral body another one is in the iliac bone so if you had the biopsy obviously everyone who does bone biopsies you would want to go for this lesion very easy straight shot and biopsy this lesion but look at the diffusion here so this was not as bright this was very bright in adc this was dark while as this was bright so obviously it makes sense to biopsy the l5 rather than going for the chip shot iliac biopsy here so it can at times guide your biopsies also another case of plasma cytoma that is involving the sacrum and this is the pre scan you can see the complete destruction of the sacrum was complaining of low back pain and this is a stir image and this is your diffusion and perfusion this is this is restricted diffusion and on treatment again stir is pretty much the same or looks even brighter than the prior study but look at the diffusion weighted images completely changed from pre-treatment to post-treatment again you can pick up the phone and give your colleagues a call and tell them that hey this is actually going much better than what it's looking on anatomical imaging so a huge a huge thing for for patient care actually we all know about the claw sign and I don't I don't want to go into much detail about that it's a long drawn process with mordic changes so you do get the typical claw sign in such patients worse is when you have involvement actual discitis osteomyelitis in which you will have some restricted diffusion within the disc space rather than having the claw sign again in mordic type changes so that's that's one more use of this okay moving on now to the dynamic dce contrast enhanced imaging is another modality that we use in the spine and it's the uptake of the contrast that is measured over time and gives you the changes in the signal characteristics it's a long scan it takes about five minutes scan it's a dynamic scan you get the pre contrast you get the arterial phase arterial venous phase and the delayed venous phase imaging so and you can come up with multiple parameters in a dce perfusion scan so you can you can get the plasma volume which tells you about the number of blood vessels you can have the K trans which is a measure of the vascular leakiness and then you can do the wash in wash out and the peak enhancement or other measurements if you're doing really a quick qualitative measurement of your dce perfusion scan these are the parameters that you'll be looking at really very closely uh let's go over a case example here so there's there's a mass that is involving lump or sacral spinal canal here it's it's bright on t2 star it is enhancing like a light bulb here you can see the tinkle sac here this is the ventral epidural space extending into the spinal under the foramen at that level so we were thinking about hemangioma thinking about plasma cytoma we were acting we were also thinking about necrosis cordoma here and so the patient was was sent to me for biopsy so as I went to biopsy this I came in from one side the moment I entered the spinal canal there was excruciating radical pain down so I stopped from this side I came in from the other side but the patient again complained of extreme radical pain going down the leg so I really couldn't get a good biopsy there was absolutely no way that I could call so often FNA and really non-specific pathology results came back the patient was taken to surgery and at surgery it was a cavernous hemangioma that was patient uh probably about six to eight weeks later I had this patient who had lower back pain and here almost similar appearing T2 signal and enhancement involving the whole of sacrum we could get hold of her prior scans and you can see that there is a progression of this process over a period of a couple of years with now really extensive involvement and again we were we were thinking about this usual culprits here at Hopkins we are like almost like a Cordoma magnet so we're really careful about not missing the Cordoma especially with such bright T2 signal but this time around so we did the biopsy as I put my needle in it was all blood so it was it was a non-diagnostic biopsy but we did the diffusion imaging and you can see it's about 1500 ADC so that was good and reassuring to me we did a perfusion scan on this and you can see how this thing is filling up over time so this is the arterial phase this is the arterial venous phase and this is the delayed venous phase and you can see that this is a clear card diagnosis of a vascular etiology lesion so this was a hemangioma and patient went for surgery that's exactly what they found on surgery was there since the vascular malformation so in the DCE perfusion you just give the contrast contrast goes in from the intravascular space into the extravascular space and over a period of time some of the contrast will diffuse back into the intravascular compartment and this movement of the contrast back and forth is plotted against time curve and you come up with all the different parameters that you use to look at the type of perfusion imaging as I said a quick semi-quantitative review you look at your K-trans which is your permeability coefficient you look at your BP which is your plasma volume and then you look at your peak enhancement washing and washout phases and you can really come up with what is going on and but if you really want to do the whole nine yards then of course you have to do the deconlucent method you have to have an arterial input function and generate all the naps and all that and by doing so you will get many more parameters that you can look at the VE the KEP reflux coefficient but typically VP the K-trans peak enhancement washing and washout is what's needed in the spine world and of course for pathological entities it has to be higher while as inine entities it will be much lower so this is just the image acquisition what we use so let's go over a few examples here so this is a new onset back pain in the patient with lung cancer so you can see very subtle enhancement the patient had some neurogenic tumor also which was quite incidental as you can see here but what we were concerned about was was was lesion here so we did our perfusion imaging this was diffusion it was bright on diffusion had some restricted diffusion this was around if I remember correctly it was around around 12 so it was right at that intermediate zone and this is the non-contrast portion this is the arterial phase this is the arterial venous phase it was bright and then you can see the the K-trans was quite high and this biopsy did through it to be metastatic disease this is a patient with a renal cell and you can see osteosmetastases that were treated with SBRT so if you do fusion scan there are multiple lesions here but it tells you exactly which one is still avid and metabolically active while others which are there on our anatomical imaging are not metabolically active and are well treated lesions post SBRT. The caveats that you had to be very careful about is that acute benign osteoporotic compression fractures because it will have higher blood flow to it and so that can be very bright on if you have an acute compression fracture deformity that can be bright on your DCE perfusion imaging so be careful about this spit volume. These are just some examples again of a fracture with with this. This is another patient of ours here you have two lesions there is lesion right here which has some heterogenous signal and all that and then there is lesion here which is bright on almost all sequences so we're thinking that this is a hemangioma while as this is a metastatic process there in this in this patient and when we did our perfusion imaging actually both turned out to be quite bright so both levels were metastasis this patient also had a nodal based metastasis up in the brain. As with perfusion with predicting prognosis predicting treatment response this is another value of your diffusion imaging and here you can see your anatomical imaging you have involvement of two vertebrae here so completely infiltrative signal in L4 involvement before radiation perfusion demonstrated that only L4 was metabolically active the L3 was was normal metabolically and this is post SBRT now four months later so we have if you were comparing these two scans you would have said that the L4 is pretty much the same and obviously there are new lesions that have developed in the upper lumbar vertebral bodies but L4 would have been like stable disease but the perfusion actually demonstrated that the L4 was now metabolically inactive didn't show any increased perfusion parameters and obviously we have increased perfusion in these pastases so really helps you to convey this information to your treating physicians that whatever they are doing is actually working although anatomical imaging is lagging behind what you're seeing from these advanced imaging parameters. And just few other examples patient with the HCC back pain here you can see diffusion here high ADC value right here this is post treatment chemo in RT obviously it has decreased but there is still enhancement there but then how you have started to see facilitated ADC value in here so that means it's actually even though it's enhancing quite a bit it's responding very well to treatment and this is the K trans and the VP there's there's really nothing here so excellent results from their local treatment. Patient with RCC back pain here you can see the diffusion perfusion is quite high obviously on anatomical imaging you see it but if just following up on anatomical imaging you would have said that yeah this is improving but you still have multiple areas of enhancement within this so there is some active disease based on this post contrast and stored imaging but even you look at your diffusion and your perfusion there's absolutely nothing there so it's metabolically inactive although we are still seeing some changes on our routine anatomical imaging. Just example so you can as I said that you can quantitate it here VP was 3.4 now 0.8 170 versus 30 so if you're a person who likes numbers you can always quantitate it takes absolutely more time to do all this but what can be done. Chemical shift artifact has been in use especially by MSK colleagues for many many decades in neuro specifically most of the neuro departments don't use chemical shift imaging especially in the spine I have found in some cases it to be of real clinical benefit and if you are able to get these imaging and now with the newer scanners it's automatically generated and if you haven't just just look at this and sometimes this will add value to to what you're looking at and of course we know and in phase water and fat couple each other and you'll have high signal while as an out of phase imaging and to a TE of 2.4 you will have opposite fat and water dipoles so they will cancel the signal each other out and should be all dark on outer phase imaging and any any variation from that fact makes the lesion more conspicuous so looking at this case obviously this is a straightforward case this is there's involvement of the bone here you can see on the in phase out of phase imaging at this level there's complete dark signal there's there's increased signal on outer phase imaging which you should not be seeing and then there are focal areas of increased signal in this vertebral also which is also abnormal because you should have complete dark signal on there so it does it does help at times another case here you can see in phase and out of phase out of phase this is completely dark so so there's there's really nothing frequent changes rather than any infiltrative residual tumor left behind obviously all these all these imaging that I'm showing you both chemical shift they cannot be read in isolation and you had to be getting all of those these parameters in a patient and then then seeing what's happening on all these sequences rather than just seeing one and this is the diffusion made of image in the same patient absolutely nothing there in that area you'll get a lot of fdg pet and cancer patients so if you are evaluating these spinal compression fractures at times you will you will get an answer based on your PET scan but typically you don't obtain a PET scan to look at or further evaluate just the spinal compression fracture and try to differentiate whether this has benign or malignant many numbers have been thrown when it comes to fdg bone pathologies usually anything between suv of 3 to 4.7 is taken as a cutoff which is towards the malignant end of the spectrum some people even go and say that two standard deviation above the liver suv is should be taken into consideration so there will be there are a couple of papers that that mention different suv numbers when it comes to fdg pet and bones obviously the two fractures can have very high fdg values and you have to be very careful about that fact as with all other imaging modalities that i talked about uh this is a case in which patient had history of cancer he had this lytic-apairing lesion involving the posterior aspect of the vertebra really really fdg avid ended up doing a biopsy and and and i turned out to be actually tb uh this is another patient similar to one that i had shown earlier with the schmurl's node and here you can see on ct very very characteristic schmurl's node there are some sclerotic area just in feeder to the schmurl's node uh PET scan was done it was quite bright on PET scan and actually biopsy did demonstrate metastatic disease rather than just up and i'm looking schmurl's node there so so that's he and you do you do get your PET scan routinely for cancer or the whole body PET scan for cancer surveillance also so make use of that at times when you are looking at your osseous lesions also in case where i think advanced imaging really made a difference uh and and so this is a patient who had colon cancer and had a pre-sacral mass of the patient has had surgery and was radiated in this region and you can see both bright t1 t2 there uh signal and this is the post contrast fat saturated so everything was normal post treatment and this is eight months later scan patient started to complain of some low back pain and that's when the scan was repeated and now you see this dark t1 by t2 and there's enhancement some signal characteristics on the opposite side that there is no uh definite compression in sorry a fracture of the sacral a laugh post radiation doesn't look like the cortex seems very smooth and i'm i'm showing you the actual impression from the anatomical scan here and suggested recurrent disease uh at at that level uh so i wouldn't i wouldn't really argue much with that because you really can't you can't really say uh can this be recurrent disease absolutely based on this scan absolutely can't be recurrent disease or this could be some changes associated with radiation so we ended up getting the patient back we did the diffusion this is my adc this is in 2000 i felt very very comfortable with that number this is my profusion scan there's nothing in the profusion scan that worried me ended up uh biopsying this patient just to make sure we're not missing anything and the biopsy result showed uh reactive digestive of radiation induced osteitis so really we had made the diagnosis based on the advanced imaging uh and and then just see that what we were seeing with advanced imaging is is actually uh fight uh this is one patient where it was a little humbling again so this is a patient with conrosarcoma of the femur had developed this lesion in uh one of the lumbar vertebrae a bit of pain uh there so this is the mr that we did this images it was enhancing so we're thinking of static disease uh there so we ended up doing again diffusion diffusion on this adc value was again 1500 ish uh this is the non-sportion this is the arterial phase and and this is the latinus phase uh based on the profusion it looked suspicious based on diffusion back then really i did not uh i was i was not comfortable we were we were still believing that 17 1800 and about is uh is good and anything below that falls in that intermediate zone now at this time i'm okay with this number 1500 in bone so we we were we were favoring this to be uh astasis rather than a benign etiology so i ended up biopsying it and the biopsy demonstrated just matter fibrosis and and no tumor and going back my diffusion did tell me that 1500 number was there so diffusion was actually right about this case uh one more case example so this is a lung cancer patient i was complaining of some pain in the iliac bone and here you can see uh that this is your pet scan it's very abdg ever this is my diffusion adc is bright right here and this is scan this is the chemical shift and you can see increased signal on the opposed phase imaging for some reason i don't have a profusion imaging on here but nonetheless uh diffusion showed me this pet showed me this so there was uh i was leave uh there and did up uh biops no this is sorry this is the profusion so the profusion also showed high high high uh profusion parameters in that lesion so we were thinking more towards uh the malignant effect from metastatic disease ended up biopsing and the biopsie turned out to be a pageant's disease involvement of this iliac bone but going back again my adc value was very high so now i'm at a point where really i if i have to if i have to pinpoint one area of these advanced imaging i'll probably go to my adc diffusion imaging rather than the profusion imaging obviously as i said again you have to have all these parameters in place and look uh or at all of them together but if i have to pick one i would i would really go with my diffusion imaging and the adc values and i'll end up with this case again uh sacral mass uh kind of heterogenous on t2 weighted image this is spoke quite bright uh adc was nine hundred and ten obviously this is malignant so and and and the profusion profusion imaging also it really enhanced very early and very brightly in the arterial phase so we were thinking about uh a paragon leoma here or a hemangioblastoma here uh so so that was my thought process but they wanted me to go in and biopsy i biopsied it it bled so much that i had to actually put gel foam uh needle because the blood was just porting out to my biopsy needle so we had to put gel forms it knew it so it's a very vascular tumor and then it turned out to be a solitary fibrous tumor on on pathology so these are these are just some of the characteristic appearance that on on on see this is the most solitary fibrous tumor early arterial phase this is your thyroid max again arterial phase so when you have something that enhances in the arterial phase uh you tend to think about malignant etiologies rather than they are not enhancing in the arterial phase on your phase on your profusion scans so uh advanced imaging can play a very crucial part in differentiating benign versus malignant lesions as i said that you do not need to do this for every case uh because most of the time your anatomical imaging will be able to make that distinction but you will be faced with cases where the anatomical imaging cannot make the distinction and that's where advanced imaging techniques come into play and help you to differentiate uh this and as i showed you some case examples about prognostication of care whatever your your radiation oncologists or medical oncologists are doing can really help them and and and uh is the confidence level after you tell them what's happening metabolically in that area that they have uh they have but just a few things to keep in mind when you try to differentiate benign versus malignant compression fracture and thank you very much for your attention uh any questions now let me see yeah dr con we're up we're up at time but if you want to answer a couple questions sure great i will read them off to you um how to differ lymphoma changes on a t1 from post-radiation change on mr uh lymphoma so lymphoma is a infiltrative process so as i said when you are looking at bone uh you should be looking at your t1 weighted images and any deviation from the fact that your normally your t1 signal should be brighter than your adjacent disc and any deviation from that fact should alert you to some abnormality so lymphoma if it infiltrates the bone it will make your t it will make the t1 signal darker while as radiation changes usually typically will be bright on both t1 and t2 weighted images and they'll be even brighter than the normal t1 weighted images that you signal now if you develop a post-radiation fracture then obviously you will have again loss of a signal but then you should be able to see some cortical breaks even on your MRI you will lose the normal dark cortical signal on mr so that's how you differentiate between the two okay how often our osteoblastic metastas don't have local edema and look like bone island and how do you differ from bone island only on mr osteoblastic met really are devoid of edema so so it's very hard to make that distinction only based on MRI and really as i alluded in my lecture you have to have a CT you have to go by bone density measurements and look at the edges of the lesion as i said a little speculation favors bone island versus osteoblastic metastasis but i really don't think that there is any concrete literature evidence that helps differentiate uh of osteoblastic metastasis from uh from bone island on only based on MRI characteristics i don't i don't think so if if someone knows about it please let me know because i really don't think that from anatomical imaging per se there's you can differentiate between the two should dwi and adc be done routinely for spinal imaging uh no well if you are able to do it that's great it will be very helpful to you but i i don't we don't we don't do it routinely in our hospital in our practice because it takes time uh and as i said these these advanced imaging techniques should only be done for specific cases where you're not able to answer the question on your routine anatomical imaging and then you can add these imaging parameters the next time you scan the patient for a follow-up uh your sequences and try to answer the question that your clinical colleagues but not not routinely not routinely i won't i wouldn't use that there's there's still a lot of time before uh we get to a point where diffusion is used like we use diffusion in the brain world excellent what is the timing of a dynamic study how many sequences do you take in a dynamic study uh so as i said this is a dynamic scan uh so it's a five-minute scan or after you inject the first you you do a non-contrast run through and then after you keep on imaging that area of interest for about five minutes so that you you get all the uh over time you get all the parameters you get the arterial phase arterial venous phase delayed venous phase so it's just like what we do for pituitary dynamic pituitary imaging up in the brain that's exactly the same parameter that we apply here so it's it's a five-minute scan it takes takes dce uh takes a longer time you can't really cut on time and say for example use a dsc technique in the bone because dsc technique is is a g re technique and and g re will just kill your scan because of the osseous elements that are present there so it has to be a t1 weighted sequence a profusion sequence which is which is your dce but but again five minutes for every dce scan so you're adding five minutes for sure okay all right we'll do one more um in my non-dynamic post-contrast scanning is there a reason to scan and delayed phase if there's no early enhancement if you are doing a dce that's you will get that uh for completion sake so i wouldn't just curtail the dce right in in between and just get the arterial phase in the mid arterial venous phase but if you want to save time theoretically yes it is possible to not get the delayed phase imaging but remember i showed you few examples of hemangioma which fill up quite late so those vascular malformation you you will have that degree of confidence at times to say that hey this is actually a vascular malformation if you if you just cut short the imaging well dr con thank you so much for your lecture today and for answering those questions and for everyone on for participating in our new conference you can access the recording of today's new conference and all our previous new conferences by creating a free MRI online account be sure to join us next week for a new conference on thursday august 10th with dr susie bash for a lecture entitled critical updates in the dynamic landscape of Alzheimer's disease and dementia imaging you can register for this free lecture at mrinline.com follow us on social media for updates on future new conferences thanks again and have a great day thank you bye bye