CT-Dual Energy -Pulmonary Angiography - Iodine Maps Tutorial

Hi, there's a small child placed and welcome to our first dual energy CT tutorial. We're going to talk about City, Palm and angiography today and focus on Iran Maps. And every tutorial is starting with a brief presentation about the topic and is then followed by some clinical analysts. So together we will analyze some clinical cases in the same way as we would do it in our. Daily routine. I'm only going to briefly talk about the physics of dual entry city. This tutorials are really meant to. Give some introduction of the insides, how dual energy can help you in your. Daily basis. But will Andrew City is based on the simultaneous? Image acquisition using tool to voltages at low and high KV. In this allows you for material selective imaging material differentiation, so this is the basic principle. And in Parliament angiography this can aid us to visualize the pulmonary. Iodine distribution. Single via is the software we're using for this purpose, and an automatic segmentation of lung tissue is performed. And these images can then visualize perfusion deficits in addition to your standard NPR and RIP images. So with traditional city, you would only have. Quite normal NPR map in 3D. Reconstructions in this clinical case, here we see a. Occlusion of the left lower. Artery and we can see on the volume rendered map images. That this year leads to a poorly opacification in this area, here highlighted. And when we see this and 3D perfusion Maps, we see that this becomes more distinct. And there are also different types of color coding oranges most common. It has also been. Used in this more colorful coding, so this is an add on to your traditional approach to analyze the CD palmonari angiography datasets. So the images we generate using this technique is. They are similar to. I would say the traditional primary scintigraphy as we know it from nuclear medicine. Here's another case, example. With this best low clusion here on the left side leading through this perfusion deficit. So these images are very useful in the decision whether an vessel occlusion in case of pulmonary embolism leads to perfusion defects. So we can say. Analyze your permanent geography datasets in terms of the hemodynamic significance of embolism. It's important to understand that these perfusion defects are typically wet shaped. Is in this example. Here we have an incomplete occlusion of this peripheral, Paul nary artery, leading them to this wedge shaped. Perfusion defect. So Dual energy provides you with information beyond the mayor, structural analysis of permanent geography and of course also other. Exam techniques without any additional radiation dose so we can reconstruct. Construct these images and. Analyze this data sets as an add on to your standard approach. To get more information and improve your diagnosis. It's important to acknowledge the fact that a partial occlusion of common the arteries may not cover cause perfusion defects. So it's important to acknowledge the fact that an unremarkable iodine map does not exclude pulmonary embolism, because when you have only a partial occlusion of arteries, this may not result in significant hemodynamic changes. So we want on either point out that the additional analysis of your normal structural kepier images is mandatory and your diagnose should also. Always be based on the traditional city analysts approach, and then as an add on. Analysis of. Dual energy images is performed. However, in our clinical experience, it has been proven to be very useful in the emergency setting. So when you receive a normal item distribution over the complete pulmonary arterial circulation, this may indicate that no severe embolism is present, so it's definitely very useful in the acute setting. Another important application of dual energy in CD pulmonary angiography is the automated volumetry of perfused lung tissue. So do a single via provides you also. With automatic quantification of this volumes, for instance here. When we see so you get this table in the end. Indicating the total volume of perfused lung tissue in cubic centimeters or milliliters if you want. And then also to compare the right and the left lung. Respectively, so if you have a subjective impression of your. If an embolism is present, you can also support this with credit head of data. And then decide which side is maybe more affected. And if you want you can also go to the low bar level and go to the as you see in the table the lower, upper and middle are. So this quantification is also important to get a reader independent and immediate estimation of global perfused blood volume in the acute setting. As we are in the area of. Quantification is always point out that we. Needs. Better quantification techniques and dual energy is very useful for that as well. And also it has been shown that the profuse blood volume, which is abbreviated as Pve, commonly that this inversely correlates with the tromba slowed also para meters. From the laboratory. Results of embolism severity and also the necessity for ICU admission. So, the higher the perfused blood volume, the less the patients get admitted to ICU, for instance. And these profuse blood volume also has been shown to have predict the value for patient outcome and also correlate's. With right heart strain so. When you have more perfusion perfusion defects than the more right heart strain you will see in your patients. And right heart strain is one of the most important conventional. Signs of embolism, severity and clinical significance. The pros and pitfalls of this island Maps it's very important to always double check the correctness of the automated lung segmentation that is performed becausw. You often see sparing of peripheral areas and especially this select. This is can mimic perfusion defects. However, these select assist you will be very. Quickly be familiar with that. These are usually not wet shaped as I have shown before. They're more Half Moon or sickle shaped. And also it's important to have a. Have a look on your data sets in the long window before you analyze the perfusion. Auridon map cause structural lung disease like fibrosis and also see OPD. In this patient you will have inherently an irregular perfusion pattern. And then the value of item Maps may be limited in those patients, so always. Also diagnose, of course your primary data. We already talked about that and again normal item distribution over your item Maps does not exclude PE. So always look have a look at the structural NPR as well. And without a thank you very much for your kind attention. And then now let's move on and analyze some clinical cases. OK, let's get started with our hands-on part. So in your single 3D workstation you see, then when you open up the patient. In transversal Corona and sagittal planes, your data set. It's important to get familiar first with the layout of this application. In dual energy you have here. On this button in your middle bottom you see that you have the lower. Chloe Vault data set and Yourt infiltrated hike. Heavy data set and the dual energy composer indicates you whether you have, for instance, here 100% the locate the data set and also you can go. Completely to the high Cavey data set so. Have a quick. Assessment of contrast conditions. You can also use this in clinical routine. I personally tend to go always to the low cavey. Data set and for instance, when you have 80% of the low energy and 20% of the hike heavy. This would be in 0.8 linear blended or also called mixed image. And also very commonly used is for instance the setting of 0.6. This would be bad this one. That and you have 60% of the low KV limited linearly with 40% of the 150KV. Then second, it's important to understand what is this circle actually about. This is not. Found in our conventional standard city and their circle indicates you the dual energy Citi Field of views. So dual Energy Information is only present within the circle. That's why the circle is also important, cause very commonly when you start with dual energy, colleagues may ask you why is the circle present in our data set and I'll show you while this is important. For instance, look here outside the circle. You won't see any changes when I modify the linear blended composition of data sets. To see this, the change is only present here when you focus on this subcutaneous fat here, this is now. Visible in this case very nicely and let's go back to a setting of. 5050 this would be here M 0.5. Because when you don't. Want to have this circle in your images? You can simply hide it and so on. The left upper corner you simply click on FOV, which means field of view. I know. You have an assessment like in normal structural parmenion geography. Also I personally prefer to hide this cross here and this you can. Said here on the left lower corner. If you click on hide lines OK, let's have a quick overview. Overall patient. So we see in this patient. This patient had severe. Shortness of breath, very acute. Also had a prior history of. Deep vein Trumbo, sis. And we see. OK, there is segmental embolism present on both sides. And when we go here in this area, for instance, we see that we have complete or collusion of peripheral arteries. On the one hand, and we go to other areas and assess those better. OK, there is severe present. PE also found in the lower lobe arteries. And here in this case, for instance, we see that this vessel occlusion is incomplete. So here I would be interested. Actually we see a bit of iodine opacification in the peripheral vessel areas. So is this really? Hammer dynamically significant and will this lead to perfusion defects in this area, for instance compared to this area on the right side? So this is information I would be interested in obtaining. And when we assess P like in our standard approach, we see here that there is quite a bit of right heart dilatation and right heart strain. So this is definitely Despite that this is another central PE. This is will definitely cause. Clinical symptoms and explains the shortness of breath and. This. Patient and when we measure. For instance, the diameter. Of the right. Ventrical of 4.22 centimeter compared to the left ventricle. We see that this diameter exceeds the left ventricular diameter by far, so definitely significant right heart strain. And now let's have a look at our dual energy analysis. You click here on long analysis, so this is pretty straightforward and. Then we have again an overview of the pulmonary iodine distribution, and we see a very inhomogenous. I don't distribution due to the. Occluded arteries. But we see on the. One hand that this is this is for instance wedge shaped. Also we see. What shape effusion defect here? We see that this is here more distinct than on the right side. So this is a mix of complete oakla, occluded arteries and partial occlusion. But we can definitely say OK, there is a significant impact on blood flow. On both sides. Subjectively, however. The maximum decreased blood flow we see in the upper part of the left lower lobe. And. Also very useful is to analyze this on 3D volume rendered images. This would be kind of this scintigraphy like image impression. So we see a lot of like. Material on the surface of the. The body of the patient and also the trachea. The two within the trachea is very well placed, but I would like to cut all this. Volume solid and this you can simply ensure. When you click here this button here on long isolation. So now it's beautifully shown. What we're actually interested in. And as I already. Mentioned before, we see in the upper part of the left lower lobe. Almost. No perfusion, so this is really severe. Reduce blood flow here, but also on the right lung. And I personally prefer also when I already have an idea where the most hammered anemic. Impeded blood flow is found that we punch this out and cut off, for instance, this volume to diagnose the left side. Specifically and then we click here. So this is important in. In single you'll find here in the left upper part the punch tool. For instance you ranges tool to reconstruct images. On the right you can measure distance lines. Window setting and verb T Gallery is found here and on the left side you will see also be appearance settings for thin MIPS, orthic, MIPS, whatever you want. But let's go back to this. 3D image modification. We click here on the punch tool. And then we carefully. Cut out the right lung. Here from this volume, double click this and. Then we unclick the punch tool. And center this centralni in the image. So when you click in the center of the single via layout, you can. Move this volume and when you would go to the left or to the right side, you can magnify this volume on your right mouse button. You can turn this volume and. Very nicely assessed the pulmonary arterial. Perfusion and we see here this significant wedge shape of perfusion deficit. And this is definitely very nicely shown in this particular case. So we see in this case that dual energy provides you with additional information beyond your structural. An NPR approach in conventional city. So another important application of dual energy and your an analysis of pulmonary and geography data sets, is, as I briefly mentioned, in the presentation the automatic quantification of the perfuse blood volume. So you can not only have. More enhanced and comprehensive subjective revelation, but you can simply quantify that in single via. And how do you do that on the left upper part here? If you have the long PV options and volume based options, and you click here on volume based. And make sure that this. Button here is checked. Then you go to your findings navigator on finding details. It opens up here in this window. And then you go on long analysis. And then you click here on the right side on evaluation. And then you get this. Table here providing with the quantitative volume that is perfused in this. Patient and you have an overview of which side is more affected, and this is, again reader independent. And completely objective. So we see here that the right lobe at the right lung is more perfused in the left lung. So more hammer dynamic significance on the left side. And then it also qualifies this further according to the right upper, middle and lower part of the lung and also on the left side. And this is also matching or clinical subjective impression that the left, lower and middle parts as you see here. Are more affected compared to the right side, so again your diagnosis of palmonari embolism is not based on dual energy CT images alone, but your standard approach would be substantially more comprehensive. And provide more information using dual Energy city technology. And with that, I thank you very much for kind attention and see you next time.

Energy CT Dual Energy CT Dual Energy HAR HRP HRA CT Dual Energy point CT Dual Energy CT Dual Energy QUANTIFICATION - AUTOMATED VOLUMETRY QUANTIFICATION OF HYPOPERFUSED LUNG TISSUE PRINCIPLE OF IODINE MAPS APPEARANCE OF PERFUSION DEFECTS DEFECTS o. CT Dual Energy Findings details Parameters Findings Evaluation No PE Lung 11 Automated Quantification of pulmonary perfused blood volume DUAL-ENERGY CT TUTORIAL #1 21 38 31 41 101 Full 31 "n of Unennancea Always dou e-cheå< the correctness of auto ated lung Lung Left and Rlght Lung Always double-check the correctness of automated lung Iodine maps may be helpful in C-500 V-500 V-600 L-500 "-500 -600 MM Dual-energy CT acquisition with 2 15+15 15+19 15+19 pulmonary scintigraphy segmentation. There IS oftÖmsparingdffØeripÅeral åieas and Pmtg of Ratio Analysis segmentation. There is often sparing of peripheral areas and Rlght- Upper Rlght - Upper Right - Upper indicating weather vessel An unremarkable iodine map does not exclude pulmonary of Voxels 96 of Voxels (HVI tubes at low and high kV allows for immediate, reader-independent Right Right- dystelectasis can mimic perfusion defects (however, these are usually Orange color-coding and an iodine overlay on a normal MPR is most occlusion leads to perfusion Len - embolism, because partial occlusion of arteries may not result in Total 45±13 101 107 105 MM material-selective imaging Middle Len - Right Right- Rtght 963 99 19 44 441 defects not wedqe-shaped) Lung L ung 21 24 Minimum Minimum. Maximum. Maximum (Lwg P -600 V-600 Visualization of pulmonary iodine o" THIN embolism Rtght - Lower -650 -600 655 and 113 121 46 12 36 10 81 21 31 Perfusion deficits are typically 46 13 Right - Middle 105 101 RAH distribution ARF RAF RAH 21 Right - Upper 655 19 17 105 50 112 17 wedge-shaped (but not RAF 432 121 44 441 81 24 99 20 441 44 21 101 Automated segmentation of lung exclusively) 20 107 13 25 28 15 48 12 46 12 46 13 ± 12 449 inherently Findings Navigator Findings details 441 17 105 107 99 50 12 112 113 tissue Findings Navigator 28 121 113 34 38 113 112 However, in the emergency setting, a normal iodine distribution MM Information beyond structural laboratory parameters of Erosion Range. 50 Quantitative volumetric data No Iodine maps visualize lung 34 41 44 41 105 107 120 107 105 109 121 104 101 CT PA without additional Partial occlusion may not lead to perfusion defects, so a -960 HU of perfused lung tissue Maximum. Maximum' Minimum' MORITZ H. ALBRECHT, MD MD -9600 -600 perfusion defects in addition to radiation dose normal iodine distribution does not exclude ulmona 113 19 15 113 99 121 15 104 121 107 120 CM 5 44 HV corresponds to 100% standard MPR and MIP embolism Albrecht, Zhang, Schoepf, AJR 2016 Automated Meinel, Schoepf et al, Investigative Radiology, 2013 27 20 21 28 121 Tools Tools Henzler, Schoepf et al, JCCT lung segmentation Schoepf ei al, Inves igative Radiology, 2013 Wleinel, (Meinel, Schoepf el al, Investigative Radiology, 2013 Schoepf el al, Inves igative Radiology, 2013 Schoepf el al, Inves igative Radiology, Tools Albrecht, Zhang, Schoepf, AJR 2016 Meine/, Schoepf et al, Bauer et al, Eur Radiol, 2011 Bauer et al, Eur Radiol, 2011 Tools 11:02 AN 10:57 AN 1:20 AN