 with us. So he's a staff ideologist at Jerevenski Hospital of Hamilton Health Sciences. He's an assistant professor at the McMaster University. His specialty is a breast and body imaging and areas of interest are cancer imaging and resident education. He'll be speaking on MRI or ads. Thanks for joining us and may I know would you? I'll just stop my screen share. Thanks for the kind introduction, Gauri. And first of all, thank you all the organizers of the 21st MRI teaching course. It is it is my privilege to present my cases and some of the teaching material here. After we have such amazing talks about pancreas and all other areas of body imaging, we are going to switch gears a little bit and go to one of the hot topics of the current date, which is MRI or ads. So let me share my screen and make sure that everything works fine. At any point, if you have any questions, feel free to use the chat and Q&A session. Even if I'm not able to answer the questions live, I may take them later on in the interest of time. But let's see how we do today. So without any further read, let's jump on to today's session. I have basically titled it as MRI or ads and what radiologists need to know. I know that all these American College of Radiologists and RADs have been an interesting thing to look at. Sometimes it's big, it becomes a little bit too too obtrusive to your workflow. If you're not doing these RADs very often, for example, PyRADs, PyRADs, then TyRADs, then ORADs, all of these RADs can be a little bit of a challenge. So I just try to summarize the most important or key point which you can take away after today's session. So I don't have any financial disclosures, but some of the sections of this presentation have been borrowed from one of our exhibits, titled number E-1881 in the American Brian Gendry Society's annual scientific meeting. So learning objectives of today's sessions will be to provide an overview of the MRI or RADs, look at a few of the pathologists, look at some of the physiologic, peritoneal, as well as tubal cystic processes, how we can classify them using this tool, then review the standardized lexicon, which is provided by the ovarian adnexil reporting data system on magnetic resonance imaging, and then how to characterize these pathologies there, then overview the ORADs MRI stratification system. Let's start with some quiz questions. Let's see how we do with these. So the first question is that, when will you use MRI or RADs? So case number one here on the left side of your screen is a woman in her 30s with BRC mutation. You have this coronal T2-weighted imaging of the pelvis, which shows you a large multi-locular cystic mass, which has multiple septations, and the septations also carry few papillary projections. Case number two will be your young woman with acute pelvic pain and fevers. It's in the center of the screen. This is an axial T2-weighted image. You can see a portion of the uterus, maybe it has some fibroid, and you can see that there is a lesion in the right adnexa. It looks like it is a, again, looks like a multi-locular cyst, but it has thick irregular walls, as well as septations and papillary projections. Then case number three is postmenopausal woman with bleeding normal CA125. This is the actual post-contrast image. You see the uterus, and also an enhancing left adnexal mass. Which of these you think is when you will use MRI or RADs? I'm seeing some options here. Most of you have gone for case number A, or the case number one, very few have gone for B and C. Let's go to the next question. The next question is that, when will you use OR RADs score five? Case number one is adnexal mass with peritoneal mass. This is an axial MRI from the upper abdomen. You can see that this is the section of the liver. Those are the kidneys. I know that this is obviously our OR RADs talk. I'm not showing any pelvic image here, just because the fact that you can see all of this soft tissue deposits, which are in the hip adrenal space, maybe a little bit of soft tissue in the adjacent to the falciform ligament, as well. Then you have a sagittal T2 added image, which shows a large cystic mass in the pelvis with a regular solid component, which is not T2 dark, and it shows enhancement better than the myometrium on post contrast imaging at 30 to 40 seconds. In case three is multi-locular cystic mass with thin enhancing separations. That's the uterus, which is pushed posteriorly by the mass effect of this lesion. Which of these you feel is an OR RADS five or a definite OR RADS five? You can go ahead and answer. We have a little bit of a split in this case. You can see some of you have gone for A, most of you have gone for B, and some for C. This is very good. This is going to help us for the discussion of today's talk. At the end of the session, you should be able to take some of the points and then classify these lesions appropriately. I know that there are lots of OR RADS, but it is important to go through the history of MRI OR RADS. To begin with, I don't know if some of you have joined for this session, sometimes in the last week of May or early June, we talked about IOTA, Simple Rules. IOTA is International Aware and Tumor Analysis Group. They started working on adnexal lesions and specifically focusing on ultrasound and how it can help in classifying certain lesions. Even based on these simple rules or 10 simple rules, approximately one fourth of adnexal lesions can still remain indeterminate and they need further imaging to classify them. That's why you can see that the OR RADS MRI score is useful in these indeterminate lesions as you can assign them an OR RADS MRI risk score or a category. This helps in preoperative characterization as well as stratification whether some lesions can be handled by a gynecologist or do they essentially need a gyne oncology consultation. Remember that if you refer each and every patient of adnexal cystic mass to a gyne oncologist, their services are going to be overburdened and there will be unnecessary delays in patient management. Obviously with MRI, you're going to have higher spatial resolution which improves characterization and studies have shown that these indeterminate lesions with ultrasound, you can see that there's reduction of these indeterminate features from 20 to 25 percent if you use the ultrasound and an MRI that drops down to 5 to 7 percent. So MRI actually does a very good job at classifying these lesions. For evaluation of contrast enhanced imaging, you definitely need to use MRI in this particular case. In a study by Tomasin et al, I have given the reference here, they saw that OR RADS MRI was 93 percent sensitive and 91 percent specific in diagnosing malignant lesions and that's exactly what you want. You definitely want to handpick those malignant lesions and make sure that they are fast tracked for their management. And this is in cases where these lesions were sonographically indeterminate and the likelihood of malignancy in those indeterminate lesions were less than 0.01 in lesions without post-contrast. So if you do pelvic ultrasound, see an indeterminate lesion and recommend an MRI and if there is no enhancement whatsoever, the likelihood of malignancy in those cases is going to be less than 0.01. So you can see that MRI does an amazing job in rejecting the benign lesions and showing the malignant lesion and that's exactly what you want to do with OR RADS MRI scoring. Another important fact here is that you should adhere to lexicon and additional descriptors because once your report goes to another radiologist or a gyne oncologist or a gyne oncologist, each and every one knows exactly what you are talking about. For example, looking at other descriptors such as a cytos, peritoneal and mesentracoronometrial no reality, all of these are going to help you in completing local staging of the disease. So what is the clinical problem here? In consistent lexicon, for example, lesions described as complex adnexal mass, they can be benign and malignant both, right? So not all of these so-called complex lesions will need urgent surgical consultation or urgent surgery. For example, you may have lesions which look like a hemorrhagic cyst with some peripheral smooth, thin wall enhancement. Technically, that is not even malignant, right? Even though it shows enhancement. So you have to watch out for what kind of terminologies you are going to use. Then what happens because of this is that there is a big dilemma about management. So you may have unwanted surgeries, delayed referral to gynecology because the services are now over bombarded with all these complex lesions going there. And then there could be possibilities where you may see benanophorectomy. For example, endometriomas with an expected rocket and skin nodule, even if it shows enhancement, it is over ads too. If the volume of the enhancing solid component is significantly higher, only then you can start to think about a malignant transformation. So not all enhancing rocket and skin nodules means that it is malignant. So you have to be very careful when you are using your lexicon so that it helps in management of the patient. So how to fix the problem? This is when the research started to go on in this topic. So they first started looking at this in the IOTA group, International Ovarian Timmer Analysis Group, a paper which was published in 2000 by Timmerman et al. talks about terms, definitions and measurement techniques. This was the first attempt at standardizing terminologies. Then we saw ultrasound simple rules and adnex models, which basically stemmed from this research. Then a morphology index was published by University of Kentucky, then GI rides from Armour et al. in 2009. Then a Society of Radiology Consensus statement in 2010, which was further revised in 2019. Some of the things which you have to consider in this case was that for GI rides and SRU consensus, they did not address the issue of inconsistent terms and they excluded solid masses from their assessment and descriptions. So that technically does not represent the entire gamut of pathologies that you will see on pelvic imaging. To improve standardization, ACR ORAD's committee was set up in 2015. Initially it started with ultrasound and then later on MRI was also added to the subcommittee because MRI is going to be a problem-solving tool and both working groups were created. The most important thing to consider here, what causes problem or what caused problem for all of the previous versions of this attempt to standardize was lack of widespread use and poor acceptance in clinical practice. So it is our responsibility that we start using lexicon appropriately so that there will be less issues of inconsistent reporting. So now let's look at how ultrasound most of the times helps you. So for the first modality, most of the times it's going to be ultrasound. So you see simple cysts less than three centimeters, then you see corpus luteum cysts with even ring of fire kind of appearance, then normal follicles and polycystic ovary. All of these are normal findings. ORADS 1, no need for MRI. Ultrasound does an amazing job. These are just benign processes consistent with normal ovary physiology. But what happened is that you start to see cystic masses which are greater than three centimeters or less than or equal to three centimeters, but going all the way up to 10 centimeters. So all of these cystic masses need some kind of a follow-up, but they fall under the category of ORADS 2, which is almost certainly benign. So in pre-monopausal age group, you technically do not need any form of follow-up, even if the cyst is up to five centimeters. This has been reiterated in many other guidelines such as SRU consensus statement. However, if the patient is post monopausal and the lesion is more than three, but less than five centimeters, you need some kind of follow-up. Then between five to 10, if the patient is a pre-monopausal, you need a follow-up in eight to 12 weeks, but if the patient is post-monopausal, then it's some kind of follow-up in one year. However, if the cyst is more than or equal to 10 centimeters, then it becomes an ORADS 3. It has low risk of malignancy. So see how the malignant potential changes, and we are going to come back to this in a second. So till now, we see that Ultrasound is doing an amazing job in picking up benign physiological findings as well as some of the benign lesions. Some other examples of typical benign findings include hemorrhagic cysts. So you see this lace-like reticulations in this cyst, which are typical of hemorrhagic cysts. Then you see this retracting clot in this hemorrhagic cyst. Again, Ultrasound is doing an amazing job. This is an example of typical dermoid cysts with the dermoid pluck or rocket density protuberance. So you see this cyst in the adnexa, which shows a low level echoes within it. And there is a rounded dermoid plug within this lesion. So this is just a sine loop or a sweep through the adnexa in transvaginal grayscale Ultrasound. You can see how it has those low level echoes and the dermoid plug. And on this MRI, actually, with a sequence, again, it shows the imaging in a better fashion. If I go back to this sine loop, you can also see that there are shadowing calcifications in the wall. Again, in keeping with our dermoid cyst, you can see here, those are echogenic foci with calcifications. Then this is just the actual CT of the same patient, which again shows you that there is a fat-containing lesion dermoid plug as well as these calcifications. So everything looks amazing till now for Ultrasound. So why do we need MRI? So let's look at some scenarios. So you have this scenario one when you have a perivernopausal woman with pelvic pain coming with elevated C125 levels and the sagittal ultrasound showing a large unilocular cyst. So in this case, it was more than 10 centimeters in size. What happens now is that you may understand that with Ultrasound and large cystic masses, you may see some reverberation artifacts at the bottom of the imager. And that can cause a little bit of a problem. So this same patient underwent a pelvic MRI examination. This is coronal T-dweller image and the blue arrow actually points towards a papillary projection in the cyst wall. So given this location, maybe it was difficult to visualize on this ultrasound and then this lesion turned out to be a cyst adenocarcinoma. So the important teaching point here is that small papillary corrections may be difficult to visualize on ultrasound, especially if the lesion is too large because of the reverberation artifacts. And this brings us back to this important point here is that why suddenly the risk of malignancy also changes when the lesion becomes larger in size. This may be one of the factors as well as well as the size of the lesion. So now let's look at another example here scenario two. If you do the ultrasound, if you see on ultrasound, it looks like there is a pelvic mass. So that's the uterus and it's kind of in the cul-de-sac as well as going into the left adenica. So it shows that there appears to be a multi-locular cyst here on this imaging. It shows low-level echos. There was no vascularity at this ultrasound. So how to put it into two or three category here? And when we do the actual, when we do MRI of this patient, this is the actual T2, actual T1 and T2, sorry, fat suppressed image, you can see that there is, there are bilateral cystic lesions and they contain incomplete septic with hyper intense T1 signal, which is in keeping with fallopian tube dilatation with non-simple fluid. So whenever you get non-simple fluid and dilated fallopian tubes, it becomes ORATS category three. If there is simple fluid and dilated fallopian tubes, even if there is smooth wall enhancement, it becomes ORATS two. So MRI really helps in risk stratifying some of these lesions. So obviously MRI is going to give you improved characterization and helping in management decisions. Let's look at some of the nomenclature of physiological processes. So we looked at some of these on ultrasound. So normal benign follicles on this sagittal T2 weather image, then a corpus duty assist, which is going to have somewhat of a smooth, peripheral wall thickening. Then you have this sagittal T1 weather image, which shows a hemorrhagic cyst, which is less than three centimeters. And then another hemorrhagic cyst with fluid levels here less than three centimeters. So remember, simple or hemorrhagic cysts less than three centimeters can be considered as normal. This is a very important point to remember. Then characteristic benign legions. So now here you have this large, this is a sagittal T1 weather image here, large homogenous T1 hyper intense unilocular cyst. It is in keeping with an endometrioma. Then you have a case here with, we already looked at this, it was a dilative fallopian tubes with incomplete separations and T1 hyper intense fluid contents. It got classified as ORATS category two. Then you have this peritoneal inclusion cyst. Again, they are typically benign ORATS two, but you need to have some kind of surgical history, which suggests that the patient might have this inclusion cyst. This is an actual T1 weather image. You see the dark uterus here. And this is a left adnexil mass, which is kind of slightly posted to the uterine fundus here. It shows T1 hyper intense contents. It was nothing but lipid. So in keeping with a mature dilatoma without solid tissue. An important teaching point here is that whenever you see cystic masses also look for papillary projections. And some of those papillary projections will help you classify these lesions further. So if the lesion has T2 dark components, remember, you have to look at T2 and diffusion weather imaging. If it is dark, don't consider it as solid tissue, even if it shows enhancement. It has to be non-dark component to call it a solid. Any cysts more than three centimeter with any type of fluid and no wall enhancement fall under this category as well. The only exception here is an endometrioma that may actually show smooth wall enhancement. Whereas for the other categories of cystic lesions, they do not show enhancement in this category of ORAS2 lesions. So now let's look at some cysts with non-simple fluid. So here you see some examples of cysts which are larger in size more than three centimeters, as well as some cysts with non-simple fluid. For example, this is actual T1 verifersive prismage, which shows hyper intense contents in this right over right adnexil mass. Then you also have this multi-locular cyst with multiple smooth separations. You have this unilocular cyst with a papillary projection solid component. Look at this. This is T2 and it is not dark. So you have to consider this as a solid component and look at its enhancement. This is a sagittal T1 post-contrast image. It shows a large ovarian cystic mass. Multi-locular shows smooth enhancing separations. So the take home point here is that unilocular cysts with non-simple fluid and smooth enhancing walls, multi-locular cysts with any type of fluid contents and smooth enhancing walls, all of these are going to be ORAS category three. Even smooth enhancing separations, ORAS category three. If you see any solid tissue in cystic masses, but it shows a low-risk dynamic contrast enhancement curve, it is going to be ORAS three. So for these lesions to fall under category three lesion, you need dynamic assessment. If you don't have dynamic assessment, you may not be able to classify it as ORAS three. So let's look at another example here. This is a transvaginal pelvic ultrasound with a large mass which is labeled here. That's the ovary and you have this color Doppler flow. An important point to remember here is that whenever you're performing pelvic ultrasound examinations, you want to you see such kind of a mass, you want to make sure whether it is arising from the ovary or not. So for example, a benign finding such as a broad ligament firebird may also have this kind of appearance. However, to assess that further, you have to just do manual push and pull on that mass with your transducer. So if you push or do allotment, if the mass is not ovarian, it will separate from the ovary. Whereas if the mass is ovarian, it will not move separate from ovary. As in this case, that's the ovarian mass. This is at rest. And when you exert pressure and push here, the ovary is again not separate from the mass, which means that it is arising from the ovary. So this is a very important point when you're doing this pelvic ultrasound to make sure what is the origin of this mass. So in this case, we did post-contrast imaging and this is dynamic post-contrast axial MR with subtracted image. So that's the myometrium and this is the ovary. So in this case, as you can see that the solid component is not enhancing as much on this 30 to 40 second phase. But moving along, if you go to the systemic or the venous phase, you can see that the solid tissue has started to enhance. However, even now it is not enhancing as much as myometrium. But this phase is most crucial 30 to 40 seconds after injecting. In this case, the final diagnosis with Merkle cell carcinoma, it's a very, it's kind of a very atypical appearance. However, they can arise anywhere. But this patient had a history of previous exhesion in the left axilla and chest wall. Dynamic assessment and lack of acoustic shadowing in this case definitely helps differentiate ovary tumors from adenis fibroids. So remember that don't walk into this kind of a pitfall and use your dynamic assessment with ultrasound as well. So what is this dynamic perfusion curve? So this is an infographic form our exhibit as I described at the start of the presentation. So what you have to do is on the 30 to 40 seconds of the post injection contrast phase, that's the time point which coincides with most of these peaking of contrast enhancement here. And then that's the ROI, which is in the solid component of the ovary. So low risk curves are nothing but, so if you see the blue is myometrium and green is low risk. So the lesion does not enhance as much as the myometrium. The intermediate risk is obviously when the lesion starts to show more enhancement as compared to the low risk ones, but it is still not going beyond the myometrium. And then high risk is technically going above and beyond the myometrium, especially around the 30 to 40 seconds after injection. So if you can, if you can consider this as your breast MRI dynamic assessment time intensity curves, it is basically somewhere on those lines. But even till this date, not many centers are doing dynamic contrast enhancement assessment of pelvic masses. Even those studies have shown that this is preferred over non-dynamic, but let's talk about non-dynamic contrast enhancement now. So what do we do in non-dynamic contrast enhancement? We can only classify them into two groups, less than or equal to myometrium or greater than myometrium. So you have a couple of examples here. So actual post contrast image here shows that the myometrium is enhancing more than the left adnexal mass. Then this is another example. The patient has multiple pelvic lesions. They were bilateral adnexal masses, but the solid component actually enhances equal to the myometrium in this 30 second post contrast actual image. And in this case, sagittal post contrast image shows that the solid component enhances greater than the myometrium. So using non-dynamic, you can only classify it into one or two categories, whereas with dynamic perfusion curve, you can classify it into low risk, intermediate risk or high risk curve. So with this in mind, let's look at the stratification and management guidelines which are published by American College of Radiology. So this is a very busy slide, but let's touch at least some of the important points. So you can always go to ACR website and download this risk stratification table and start to use this in your day to day practice. But we have basically touched upon some of the important findings here. For example, we looked at benign processes in normal ovaries such as corpus luteum cysts, follicles, hemorrhagic cysts less than three centimeter in the prima, the puzzle woman, then any cysts which are classified as follicle less than three centimeters. So we looked at these examples. Then we looked at unilocular cysts with simple fluid or endometriotic fluid components. They may have smooth wall enhancement. Then we looked at lesions with lipid content in one of the examples suggest a benign teratoma. Then we talked about dark T2 or dark DWI solid components which is technically not solid tissue and it should not be classified as solid tissue because those can be just retracting plots. Then we talked about dilated fallopian tubes. If it has benign or simple fluid content, it becomes category two. If it has non-simple content becomes category three. Then we looked at para variants. We did not touch upon this, but again para variances also fall in the category two. They do not have enhancing solid tissues here. Then we looked, let's look at some of the ORADS 3, 4 and 5. So what do we need to know is that if you see any solid tissue and if you have dynamic contrast enhancement with you, it needs to show low risk curve only then it falls in the category three lesion. However, if you do not have this particular feature, then you have to look for non dynamic curve and in that case, it falls into this category. Then you can have smooth septae. We looked at one of the examples with enhancement and then smooth enhancing walls of the system. It may also fall into this category. The most important take home point from this slide is that whenever you see peritoneal misentry, corromental nodularity or irregular thickening with or without a cytos, it automatically becomes category five. It does not matter if the enhancement is greater than equal to or less than my metrium. It becomes ORADS 5. So that is one of the examples we looked at in our quiz questions. One of the patient had metastatic disease, so that puts into a category of ORADS 5. Now let's look at some of the examples of each ORADS category. So these are typical examples of ORADS category one. So you have your unilocular cysts here on actual T2, T1 and T1 fat suppress. So it just has simple fluid contents. So this is typical ORADS 1. Then you have hemorrhagic cysts here. So remember hemorrhagic cysts up to three centimeters are considered benign. The cysts which are larger than that, you have to look at other features such as wall enhancement. Even if it has smooth enhancement, it can still fall under this category. If it becomes more than three, it becomes ORADS 2. Then let's look at another example here, just a benign fat-containing lesion. Young woman presents with, again, on ultrasound, it was just labeled as complex adnexal mass. But on MRI, you can see that it is bright on T1. On T1 fat suppress, the fat component shows suppression here. It's a very small component here. And then on ultrasound, you can actually see that there is lots of echogenic content with shadowing. So this is in keeping with a benign endometrioma. So again, falls under the category of ORADS 2. So remember, these may also have rocket and ski protuberances, which is expected with teratoma. Don't make them as ORADS 3 or 4 just because there is a rocket and ski protuberance. Then let's look at another example here. So 27-year-old with pelvic mass, CA125 was around 10. So you have actual T2, sagittal T2 and sagittal post-contas T1 where it imaging with fat suppression technique. You can see smooth enhancement of the septae. So this is a multilocular cyst, smooth enhancing septae, no solid tissue ORADS category 3. Final in this case was cyst adenoma. So remember, these are probably most of the time is going to turn out to be ovarian neoplasms. It's just that they are not malignant. So the only risk here is that there may be times when the lesions turn out to be borderline and that's the only time when the surgeons can have a little bit of a difficulty, especially if the cyst fluid inadvertently ruptures in the baritoneal cavity. But always remember that it at least gives you for the most part what is going to be the risk of malignancy. So for ORADS 3, it's approximately 5%. So post-menoplasm women with bleeding and coming with normal CA125 levels, we have this actual T2 where it image, you see this T2 hyper intense lesion, which is solid in the left adenosa. Remember, this is not a T2 dark component, correct? So you have to look at its enhancement. So this is actually T1 where it image, this is T2 fat suppressed, again remains fairly bright. Then you have this T1 where it image venous phase and dealer phase. And then you can see that the enhancement is kind of always less than the miametium irrespective of what phase you look at. So this was classified, obviously as ORADS 4 category, solid tissue component enhancement less than miametrium. This ultimately turned out to be a fibroma of the left ovary. Again, for certain conditions where you can be fairly specific irrespective of the ORADS category, you can give your diagnosis, as in this case, you can be fairly conferencing that it looks like a fibroma of the ovary. So it's not that you assign ORADS score, and that's the end of the story. You may still want to give some descriptors or some of the typical lesions of adnexa. For example, even disc germinoma, as you can give it in your diagnosis, because you know that it's going to be disc germinoma based on the imaging features as well as the presentation. Let's look at another example here. 64 year old woman with abdominal distension, again CA125 was not really elevated, but that's the sagittal T2 image. It shows a large unilocular cyst with solid components. So look at this T2 imaging sequence here, it's not T2 dark. So which means that you have to look at its enhancement. Again, this is axial T2 axial diffusion. So both show that it's not dark here. So you have to look at enhancement. So this is a sagittal post contrast T1 image. It shows you that that's the myometrium here. Those are enhancing solid components. And one of the portion of the solid component was actually quite hyper intense on the T1 post contrast phase. And when I put ROI, this component is almost having a signal intensity of 1300 versus myometrium of just 1000. So it shows that there is enhancement of greater than myometrium. So this patient did not have peritoneal disease, but the solid component showed enhancement greater than the myometrium on 30 to 40 seconds image, which means that it is ORATS 5. This turned out to be a cisternocarcinoma enhancement of the solid component should be assessed only if it is not T2 dark or DW dark. Remember, this is a very important point. Let's briefly talk about some governing concepts of ORATS before we wrap up. Remember, this tool works the best or has to be used when you have a patient with average risk or no family history, or the patient does not have BRC mutation carrier. This is very important to talk about because if you remember BRC mutation carrier women's always have a higher risk of ovarian lesions as well as breast cancers. So those will not be average risk women. Then the patients usually are not having any acute symptoms because irrespective of the score what you get. If somebody comes in with acute symptoms that needs urgent surgical intervention, your recommendation is always going to be that irrespective of the score. For example, if the patient has acute fever, spades and lots of other systematic issues going on because of biosulphins or a complex process because of infection, those are the situations where the patient needs urgent medical attention. If you see multiple lesions, you have to give separate score of each lesions, but the management is driven by the highest score. For example, if a woman has a right adnexal dermoid cyst, which is typical ORATS2 score, but there is a multi-locular cyst with smooth enhancing separations in the left adnexa, which is ORATS3, so the management is driven by the ORATS3 in that patient. Always remember that you look at characteristic lesions with other with fat. They fall under the category 2 and other features of benametrotertoma, despite enhancing separations or rockiness in audio. If there is a large amount of enhancing solid tissue, that is when you start to wonder about malignant transformation. Talk about typical diagnosis such as determinomas, lymphomas, peritoneal pseudosys, irrespective of your ORATS score. Then dynamic contrast enhancement is favored over non-dynamic contrast enhancement, but even if you don't have dynamic, you can start working with non-dynamic as at least it will give you a good idea whether it is ORATS category 5 or 4 lesion. This is a very nice table from ACR website. So these are the three situations which you will probably have to deal with most of the times and you can use these guidelines to make sure that you can follow and classify the lesions accordingly. So always talk about physiological processes and classify them as ORATS1. ORATS2, we talked about some of these examples. Unolocular cyst with no enhancing wall or no solid tissues, then characteristic hydrosulfins, including cysts, endometriomas, pyrotomas, no solid tissue. Then solid tissue with very low homogenous signal on T2 or DWI. Remember this can be just a retracting clot. All of these are ORATS category 2. Then ORATS category 5, definite peritoneal or mental thickening has to be 5. Then lesions with solid tissue, high-risk intensity, high-risk type of enhancement. Or if you have non-dynamic assessment, then solid tissue enhances more than myometrium at 30 to 40 seconds. So let me show you one quick case here. This is a sagittal T2-rated MRI. You see that there is a large adnexil lesion. It looks like it is non-simple fluid with T2 dark components. And then as we go through it, it almost has this dilated tubular kind of appearance. That's a uterus. If we go to the other adnexa, you again start to see dilated tubular structure with fluid-fluid level. So what is your diagnosis here? Again, you see dilated tube spilaterally with non-simple fluid. In this case, the MRI with contrast did not show any enhancement. So this is in keeping with a typical ORATS MRI-3 lesion, because it is dilated tubes with non-simple fluid. So let's talk about some of the limitations. With all the good things, there's always a little bit of a star there, like radio instructions carefully kind of a thing. So the limitations with ORATS MRI is that differentiation between suspicious and enhancing solid components from other solid components, this is where historically, some of the papers have found that there's a lot of variation, because if you consider Rokritansky protriburans, you can call it as ORATS-2. But if you call it as a suspicious finding, because of its enhancement, it automatically bumps up to ORATS MRI-4, which is kind of an inadvertent move, but that happens. Then inadvertent assignment of retracting clots as solid tissue, because sometimes they can show enhancement, but they are technically not solid, because they are T2 dark. Then what if the patient has hysterectomy? How are you going to compare the enhancement of the solid tissue? And if the patient has adenomasis, the myometrial enhancement is going to be fairly atypical. So all of these basically turn out to be limitation and ongoing research is going on in this field as to better standardize in these situations. To conclude, there is a good risk stratification given by MRI-ORATS, which helps in patient management. It is important to have knowledge of lexicon and terminologies, which helps in scoring and predicting the risk of malignancy. It is a key tool for deciding management plan in a resource constrained environment. For example, when to refer patients to gynecology, when to refer the patients to gynecologist for management. So standardization also helps to increase the accuracy of region characterization and improves communication between radiologists, clinicians, and allows a high impact research. So with that, I'm going to conclude and stop my screen sharing. I'll take some questions. I think I can see some questions here in the Q1A box. Okay, I think there's just one question. So I'll just take that and with that, I'll close it. If we see papillary projections, not T2 dark, but no post-contrast enhancement, how do we go about it? We can't classify a solid component. So important to remember is that if the solid component or papillary projections, if they are not T2 dark, you have to treat it as a solid component. And if they don't have enhancement, so this situation is going to arise when you have patients with endometriomas. You may sometimes see papillary projections in them. One of the typical examples is decibelization of endometriomas. They may or may not show enhancement, especially if the patient is pregnant. So in that case, you have to look for the kind of enhancement. And if the enhancement is not greater than the endometrium, sorry, the myometrium, then it is going to be a low-risk category lesion. So remember that you have to look at those as solid components. If they are T2 dark, then that's the end of the story. Don't even look at the enhancement. So I hope that answers that question. So with that, we can end the session. If you have any questions, you can always reach out to me. I will leave my email in the chat section here. And once again, thank you all for inviting me for this session. It has been a very