CT-Dual Energy - Pulmonary Angiography - Colorcoding and Mono+ Tutorial
This tutorial provides an overview of the Dual Energy functionalities for assessing CT Pulmonary Angiography including clinical case demonstration of colorcoding and mono+.
The herein illustrated statements made by Siemens’ customers and physicians are based on their own and discrete opinion. The speaker is responsible for obtaining permission to use any previously published figures or tables. The speaker is also responsible for obtaining permission to reproduce any photograph showing recognizable persons.
The statements by Siemens’ customers described herein are based on results that were achieved in the customer's unique setting. Since there is no "typical" setting and many variables exist there can be no guarantee that other customers will achieve the same results.
Some products/features (here mentioned) are not necessarily commercially available in all countries. Due to regulatory reasons their availability cannot be guaranteed. Please contact your local Siemens organization for further details.
Hi this is more stylish than welcome back to our second tutorial. Let's talk a bit more about dual energy, city pulmonary angiography and how color coded and monadic reconstructions can help us in our diagnosis. Recently and advanced monadic algorithm has been introduced that uses a frequency split technique. This algorithm is abbreviated in this tutorial as more plus. And traditional more getic images had the limitations that at KAVI levels below 75, approximately a substantial noise increase was found. But this motor plus techniques has no noise limitations anymore at local levels. And this is assured by. Blending. The high contrast of the low energy data sets with a low noise of medium energies. And why is this important? Poor contrast in palm and geography can occur in daily practice and this frequently limits our diagnostic capabilities. Regarding the peripheral. Palmonari arteries so very often, for instance in this case here we have a poor opacification of the palmonari arteries. We could of course, here exclude Central Power Menary embolism, but. For instance, here in this peripheral branches I would not dare actually to make a diagnosis with high confidence regarding a potential best look lusion. So whereas here we would say maybe it's the same mental embolism, maybe not. We can then reconstruct monogenic images at Ultra low cave levels. With an excellent contrast also in this peripheral areas, and thus we can reliably exclude. Potential vessel vessel occlusion in this patients. It's very important to. Get familiar how to handle this increase in contrast with more getic imaging, you very often will find substantially increased Hounsfield numbers and contrast conditions. For instance, in the order. Very often this exceeds thousand Hounsfield numbers, and with standard Windows settings you may get inferior image quality perception at lower cave levels. This fact has been also dressed in a recent paper. For instance, you see on the land linear blended M 0.6 standard images that. We have here the substantial blue refusion on the left side leading to this selected lung parenchyma. In which we can. Delineate tool tiny pulmonary arteries and when we apply them to optimize the contrast. Majetic plus it 40 electronvolt we see definitely. Better contrast upper pacification this. Parenchyma, but also you see that the vessel lumen is easily overestimated, so we can barely differentiate the stool vessels. And then it's important to adapt and manually adjust your Windows settings to a higher. And geography window. For instance, in this case example here approximately with a level of 400 Hounsfield and the width of 1100 Hounsfield you get then again a very nice contrast. And we can say here on the right side the contrast is more like a really strong black and white contrast compared to the standard approach where you would probably always. More say it's a dark Gray versus a light Gray contrast. So this is important to keep in mind. And very commonly it has been assumed that dual energy can lead. To a reduction of. Follow up imaging and also additional imaging and thus can lead to a more gentle imaging of our patients with dose reductions. In the nice case example for this is the application of turning a Venus chasity for staging purposes into a so called virtual city pulmonary angiography. In this case, for instance, an incidental embolism on a Venus Chasity scan was found that was initially acquired for staging purposes of lung carcinoma. And then we see this trimatic material here on the right lower. A pulmonary artery. And then we can simply Recon respectively reconstruct 40KV model plus images to increase the lumenal attenuation in the pulmonary arterial circulation nearly as high as it a conventional CT permanent and geography in the arterial phase in this substantially facilitates the assessment of emboli and also the delineation, especially in that regard. And again this is. Just an add on in case you find something. Incidentally, dual Energy City helps you with. A lot of. Additional application without any additional radiation or contrast material material administration. In this fact has also been investigated by another group, so apparently this is a very promising application of majetic imaging, and here it has been compared intra individually with standard material palmonari angiography. Studies in this portal venous scan we see here. A bit poorly opacified pulmonary artery. But when we see it here, I wouldn't be sure where the traumas exactly begins and where it ends. And then when we go to more getic images here, this is abbreviated as Mei on either 40 or 55 KV. We have more confidence. We can, for instance, say here there's a bit of a pacification here. That's the start of the thrombus, so again, a better delineation of thrombotic material. And really, compara bulto a standard palm and angiography without any additional radiation or necessity to refer the patient again to radiology Department. Is any dual energy city reconstruction mono plus should always be used in addition to the standard. Linear blended images but not replace them. This is important to recognize it's an. Additional add on reconstruction with high contrast, especially at low key levels, but always look at your source images as well. And it's important to know that when you have highly obese patients. Mona Placid ultra lock. Heavy levels maybe, but noisy. Still even with the recent advanced algorithm. And the lower the key view level, the more important is the manual adjustment of Windows settings. So switch to an angiography window with a wide window. Level and white window center just to higher window settings basically. So let's talk a bit more about the poor contrast when we actually have a true adherer CPA image acquisition. We have factors that can be influenced, for instance like incorrect bolus timing, erroneous region of interest, placement, we have breathing related effects. When the patients does not. Hold the breath as instructed. We have patients with low cardiac output. This can also always limit the contrast specifications, but also you have factors that cannot be influenced. For instance, the phenomenon called transit interruption of contrast cause from the inferior vena cava. There is inconsistent blood flow in flow in the right hard in this can sometimes lead to poor opacification or also when you have patients with reading impairment. Where you cannot administer the normal contrast media, those. And we investigated a protocol with dual energy reconstructions to overcome poor contrast CPA studies, for instance here. We may suspect a bit of reduced attenuation in this peripheral artery. But I would also not be completely sure. If this is maybe just an artifact or where the Trump's ends. And so on. And we and we then go tomorrow etic images as 40K V we can sufficiently. The linear that rombas, so we're definitely positive now that this is powerful power number, embolism in this patient and then Additionally I owed and Maps help you further in. In the assessment of hemodynamic significance, and especially this island Maps. We believe that they enhance your diagnostic confidence in our clinical practice. And we finally found that. This additional reconstructions. Have significantly higher diagnostic accuracy for segmental embolism detection, and also both for central embolism and segmental embolism assessment. We found the highest diagnostic confidence, so whenever a poor contrast is found with two energy, this is not a big problem anymore. Becausw, you add Mona Getic images and the Iran Maps. These are best in combination. And thus you can still have a diagnostic scan. So again, the necessity for reimaging the patient or follow-up imaging may be reduced with dual energy. In several studies, found discrepancy between the best objective image quality and subjective image quality at low heavy levels. So we recommend in case of a sufficient contrast iteration on your standard. Blended images better use cavey levels between 55 and 70 KV. For instance, in Orick CTA studies, when you have already sufficient contrast, don't go to the ultra log heavy levels. These should be reserved for the cases with poor contrast generation, or intern when you have inner city scan that you want to turn in an aterial city scan, then go even. More down towards the iron cage level. This would be about 40 and 55 KV. And with that, I thank you very much for attention and lower. Let's analyze some clinical cases. This patient was scanned due to shortness of breath and suspected embolism. And when we have an overview again, we can hide those lines here. You can also. Check the field of view OK this patient, for instance, is perfectly centered in the field of view, so we have all almost everything available in dual Energy Information. That's at least good, but when we? Go through those images. We see that this became more. Like in conventional order, graffi or. Truity real. And geography, but not a pulmonary angiography. So we see this decreased contrast here in comparison to the order. So without good Angie we would be. Very hammered here to diagnose. The pulmonary peripheral are areas. We also hear this. Fluid filter so far goes is aside finding. OK, So what do you do? We then can, for instance, is the first step. Go to long analysis and see if we have any perfusion defects present and this already looks quite good we have. Quite intense items signal over. The complete lung. It's homogeneous on both sides, so here your suspicion for severe PE is already quite low. So this is helpful in this patient and also this is nicely shown here. What I mentioned in the last presentation. How do select is? This looks like it's more Half Moon sickle shaped. Perfusion defects would be more. Wait shaped like this but again this patient. We don't see any hyper perfused areas. Despite this low contrast in the primary arteries. Another way now to optimize this study is to increase the contrast in the palmonari arteries themselves, and we do this with more energetic imaging. Will you go here on the left upper side of the image? All the way down to more attic plus. And click the add. And then it takes only a short time to calculate those images and now we have this more drastic data set. In more enter the imaging you have now here. From 40 up 290 KV all the options of different contrast intensities. And for instance, the normal image impression of Standard image is quite compareable to 75 KV. So again here. We would have insufficient. Contrast in the palmonari arteries. And this study would not reach a complete 100% diagnostic level. And when we go all the way down to 40 KV. We see now this substantially increased contrast in the palmonari arteries. And. And we can window this more. It's been like this. I like this one better. And then. We can focus now on the peripheral areas of pulmonary arteries. For instance, let's. Go all the way down here. To segmental levels. And even here in the peripheral arteries you see a strong Iran signal, insufficient contrast, opacification, and when you compare this in this area where we found select, this is. To the standard image impression, which would be this level? So this is the comparison. So the contrast in this area just to give an example. And kind of an idea how Moto Plus is really like matching. So even this tiny. Subsegmental artery can reliably exclude palmonari embolism. And you can also quantify this increase contrast in Hounsfield numbers. For instance, you go on the right upper corner on Dual energy region of Interest Circle, check that. And you drawn region of interest in the pulmonary artery. Quite centralny and then we get this values. And we're going to have a. Look at them. What they tell us so you have the locate the data set. Indicates a mean of Freon House field units and at 150 KV you would have 140 Huntsville the units and when we blend this linearly with 60% of the Lok Heavy in 40% of the high KV we would just linear look at 230 hansfield units and diagnostic threshold to indicate diagnostic value for permanent geography has been defined at levels above 200, so this would be still not. Non diagnostic but definitely of lesser diagnostic value. And when we go now to 41 KV. This actually I reconstructed this at 41, not 40. We would have 600 hansfield, so you have more than double degeneration in this image data set with more attic imaging and thus you can overcome this poor contrast very easily. Also, in this particular case. We look for site findings. Of which the patient has quite a lot, but I would like to point out one thing here and incidentally found renal cyst. And as we can see, the cyst. Here is. Maybe enhancing, maybe not. We don't have a true non Con image acquisition in this particular case. And with dual energy we can overcome this by having a look at the virtual noncontrast image. And this is done by checking again here on your application profile you go to virtual unenhanced. And check that and now it provides you. With an iron image. And this works. Here, with a mixing ratio. When you go all the way to the left, you have 100%. Of the nonconnah image and then you can gradually according to your. Specific case and personal preference. You can also go to a completely eiden image and now only the contrast material is shown in the contrast opacification. So you can select subjectively, say already. OK, this is on noncontrast conditions isodon cyst. There is no primary hyper density involved, suggestive for primary hemorrhage, for instance. And again, you can now also quantify the contrast. Media uptake just by drawing a dual energy region of interest in this system. Important here is also that you define. Your normalized contrast first, so you on the right upper corner you go to dual energy normalized contrast. You drawn Ahri in the order, so this would indicate hundreds of contrast. And then you're. Measurements here are already too. Four analysts, so in one arrow I. And you draw this perfectly in the lesion or normal biphasic image acquisition. This would be probably difficult to draw it completely reproducible in the non con. In the contrast enhance image. Here you have a perfect measurement because you basically measure the same volume. So you ensure that you really measure. The center of the system that maybe some of the other surrounding renal tissue, and in this particular case we have virtual and contrast 14. And it says that the. Standard image The Mixed 0.6 image has 12 Hounsfield, so there is no contrast media uptake in this lesion. And I on density further here it's says negative, but basically there is no iodine uptake. Present in this particular lesion so we can reliably say this is a simple, uncomplicated Bosniak one grade renal cyst. Here's another interesting case with patient of with pulmonary embolism in a. Choose this case to demonstrate you hold the perfusion deficits and effects normally look like. This patient had really severe. Pulmonary embolism with a. Riding Trump is here at the Parliament area arterial bifurcation. Leading to severe vessel occlusion also to several peripheral areas. So of course this patient will have hammer dynamically significant PE, but for educational purposes it's very useful here to have a look at those. So we go here, online analysis on the left upper corner again. And. When you now see OK, this is what I meant with which shaped. Perfusion defects so this becomes quite distinct here, for instance as well. So this is what we mean when we talk about which perfusion defects in comparison to the prior case which had this beautiful homogeneous iodine map. In dual energy also has another. Useful application. You can color code the lung vessels and you go here on the left side on lung vessels. And then it color codes you the. Arteries with a higher opacification here in green or blue and the ones with a low attenuation, and those are particular suspicious for Parliament embolism. They are coded in red so. This is especially useful for less experienced readers or referring clinicians. They are always happy to have a look at those color coded images. Because they kind of guide you in your suspicion which areas are particularly relevant, for instance here on the right lower lobe, there seems to be quite a low contrast media density. And. When we go here, for instance, to show mixed, you can always go back to your normal structural. Image and this is matching here several. Perfusion defects that we can see on this standard image. Let's go back to the color coded one. There's another option now to have this color coded images with an add-on often item map on top. And. This is not already bit advanced, but let's try it out because the images are also useful in particular cases. Here's perfused blood volume and lung vessels. So we click on that and now you have an overlay of the whole. Color coded approach of both the vascular system and the lung parenchyma. And look here how beautifully this correlates. With the perfusion defect, the color coded NPR. And if you would like to send those images to your packs, you will go to the left corner menu. Here you click on ranges parallel ranges. And we personally attend to reconstruct more thicker. Dual energy reconstructions. To get an overview just to avoid to let the data the data volume is too large. And we have a thickness of four of five and increment of four. We click here. The area we would like to. Be covered and here you click simply on start. And then. You have this reconstruction available. You can then also rename it and so on. An this is all what you need to know about dual energy CT, permanent geography and thank you very much for kind attention.
CT CT CT CT Dual Energy point Energy CIP A 3 ct. 80 [HUI CT Dual Energy 200 80 30 RECOMMENDED ENERGY SETTINGS FOR MONO+ ADVANCED VIRTUAL MONOENERGETIC IMAGING HOW TO HANDLE THIS INCREASE IN CONTRAST MONO+ COUNTERACTS POOR CONTRAST PEARLS AND PITFALLS FOR MONO+ MONO+ TRANSFORMS VENOUS CT INTO VIRTUAL 'CTPA' MONO* TRANSFORMS VENOUS CT INTO VIRTUAL 'CTPA' DUAL-ENERGY TECHNIQUE OVERCOMES POOR CONTRAST o, 02 CT Dual Energy CT • 3 Ranges [10] App: 90/ Sni50/ 41 Mixed Input App: 90/ Sni50/ 41 keV/ Mixed 0.6 Sni50/ 41 keV/ Mixed 0.6 App: Sni50/ 41 Mixed 0.6 LineÖrIy-bGäed M _0.6 LineÖrIy-blEfiäed M _0.6 CIE Mean: 300.61 137.7/59@5/ 235.4 HU 40 Mono+ 40 Mean: 300.61 137.7/5965/ 235.4 HU Mean: 300.61 137.7/5965/ 235.4 Mean: 300.61 137.7/0965/ 235.4 HU Mean: 380.61 137.7/5965/ 235.4 HU Mean: 300.6/ 137.7/596.5/ 235.4 HU 40 Mono+ 40k V. ono+ Virtual virtual Lung Plus Mono+ 40 ke Mono+ 40 70 kev 70 Iodine maps 40keV DUAL-ENERGY CT TUTORIAL #2 Unennancea Unennanceo Min. 169 0/ 52 0/ 3830/ 152 0 Min. 169 0/ 52 0/ 3830/ 152 0 HU Min. 169 04 52 0/ 3830/ 152 0 HU CTPA studies with low attenuation do occur in daily practice s witfi Diagnostic confidence Min: 169.0/52.0/ 383.0/ 152.0 HU y practice Case: Incidental embolism on a Max: 454.0/210.0/ 848.0/331.0 HU [11351 454.0/210.0/ 848.0/331.0 454.0/210.0/ 848 0/331.0 -gso• IHIJI Il -gso Diagnostic dilemma: suboptimal contrast opacification in CTPA CTPA IGout Lung "'-500 L"-500 V-500 1"-500 V'-500 -500 -500 • C-500 if-500 Area: 2 0 cm2 MM Area: 2.0 cm2 40 and 55 kev Mono+ As any DECT reconstructions, Mono+ should be used in venous chest CT scan for staging For the proper use of the software or hardware, please always use the Operator Manual or Instructions • Bone Iodine Ratio Ratio THANK YOU! Several studies found discrepancies between objective (CNR and Reading • Protocol 3 Lung reconstructions derived from reconstructions derived frpnp [111CT • Lung) CT PULMONARY ANGIOGRAPHY addition to standard linearly-blended images, not replace them Sni50 301 S J' purposes MM Rearing MM Reaoing Rearing Reading [11] CT 12.0/10.3/15.0 HU Mean, 14,61-221 12.0/ 103/ 15.0 HU • medium contrast • medium ntrast • hi h contrast SNR) and subjective image qualityl App: VNC/ CW Mixed 0.6/ 90/ Sni50 venous staging CT scans in this training will not be updated on a regular basis and does not necessarily reßect the latest version of Stddev: 22.0/ 17.1/ 19,0123.6/ 30.8 HU MM OProtoco' 1 Factors that cannot be influenced • low noise Factors that cannot be influenced at can be influenced • high noise Factors Mean, 12.0/ 103/ 15.0 HU SIEMENS Mean: 14.6/-2.21 12 0/ 15 0 HU Mean: 14.6/-2_21 12 0/ 15 0 HU Mean: 14.6/ HU Mean: 12 0/ 15 0 HU Mean: 14.6/-2_21 15 0 HU Mean: 14.6/-2.21 12 0/ 15 0 Max: 96,0 Stddev: 220/ 17.1/ 19,0123.6/ 308 — 17.1/ 19,0123.6/ 308 HU Stddev. 220/ 17.1/ 19,0123.6/ 308 HU - 17.1/ 19,0123.6/ 308 HU Stddev: 220/ 17.1/ 19,0123.6/ 308 HU the software and hardware available at the time of the training. Max 71 68 96 0 Max: 71.0134.0/68.0/ 67.0/ 96.0 HU Retrospective reconstruction of 40 -5 Area: cm2 Min. -38.0/-56.0/ -32.0/-52.0/ -57.0 HU Min. -38.0/-56.0/ -32.0/-52.0/ L 380/ W 1070 O Protocol 1 The herein illustrated statements made by Siemens' customers and physicians are based on their own 40keV + Max: 71.0134.0/68.0/ 67.0/96.0 HU Max: 34.0/68.0/ 67.0/96.0 HU Max: 71.01 34.0/68.0/67.0/ 96.0 HU 40 In case of sufficient contrast attenuation on standard COLORCODING AND MONO+ Area: 0.5 cm2 Area: 0 5 cm2 Area: 0 5 cmn2 transient interruption of kev Mono+ increases the luminal incorrect bolus timing/ erroneous The Operator Manual shall be used as your main reference, in particular for relevant safety information and discrete opinion. The speaker is responsible for obtaining permission to use any previously Iodine Density: -0.2 mg/ml 1-1_2 % Iodine Density -0.2 mg/ml -1_2 % Iodine Iodine Density: -0.2 mg/ml -1_2 % Case: In the venous phase, the The reproduction, transmission or distribution of this training or its contents is not permitted without CAVE: limitations have been described in highly obese published figures or tables. The speaker is also responsible for obtaining permission to reproduce any like warnings and cautions. linearly-blended images, use kev levels between 55—70keV. Less CM Diagnostic accuracy Diagnostic confidence express written authority. Offenders will be liable for damages. attenuation to levels nearly as high attenuation to levels nearly ps high Healthineers ' embolus is much better photograph showing recognizable persons. Unversrtät patients! contrast (TIC) ROI placement Segmental PE segmental PE More CM Below that, the iodine signal may become too intense Note: Some functions shown in this material are optional and might not be part of your system. The as at CT PA, facilitating the visualized with the 55 kev image All names and data of patients, parameters and configuration dependent designations are fictional Preview 5/20/2015 image D'Angelo et al, European Radiology 2017 The statements by Siemens' customers described herein are based on results that were achieved in the Advanced monoenergetic algorithm (Mono+) uses a frequency-split (Mono+) uses a frequency-split and examples only. 90/ Sni50/ 41 keV/ Mixed 06 assessment of emboli and [email protected] as standard and optional features that do not always have to be present in individual cases. renal impairment requires breathing-related effects Overall Confidence central PE Segmental PE customer's unique setting. Since there is no "typical" setting and many variables exist there can be no Mean. 3006/ 137.7/596.5/ 2354 HIJ 42 In case of poor contrast attenuation or venous CT scan, use Mono+ allows for Findings Navigator Despite the best CNR, application of standard window settings for low-keV 0.4 Min: 169.0/52.0/ 3830/ 152.0 HU technique guarantee that other customers will achieve the same results. Leithner, Schoepf, Albrecht, Investigative Radiology 2017 Gre, chant et al, Investigative Radiology 2014 delineation of arterial thrombi DE Max: 454 0/210.0/848 0/ 331.0 100 - Specificity All rights, including rights created by patent grant or registration of a utility model or design, are plus Pulmonary embolus is clearly Findings Navigator Certain products, product related claims or functionalities described in the material (hereinafter collectively The lower the kev level, the more important is the manual diagnostic opacification Mono+ may result in inferior image perception linage per Dtiop Area: 2.0 cm2 energy levels between 40—55keV. s S osmm energy lower contrast dose low cardiac output reserved. "Functionality") may not (yet) be commercially available in your country. Due to regulatory requirements, (arrowhead) MORITZ H. ALBRECHT, MD Some products/features (here mentioned) are not necessarily commercially available in all countries. visible in the pulmonary Mono+ has no noise limitations at low kev levels unlike traditional Mano Mono+ has no noise limitations at low kev levels unlike traditional Mono O Protocol 1 - Protocol 2 - Protocol 1 - Protocol 3 = standard linearly-blended After optimizing window settings, superior subjective image quality for 40 kev adjustment of window settings: both window center and superior subjective 40 kev the future availability of said Functionalities in any specific country is not guaranteed. Please contact your set,' Iodine maps may further mac Due to regulatory reasons their availability cannot be guaranteed. Please contact your local Siemens Standard linearly-blended images Mono+ 40 kev -4 Copyright O Siemens Healthcare GmbH, 2018 l' angiography and 40 kev images CT More organization for further details. Mono+ is observed No additional radiation or contrast level need to be increased enhance diagnostic endings Protocol 2 = adding Mono+ 40 kev Increased contrast from the low kV image set is combined with reduced Protocol 2 = Poor contrast — Maybe segmental embolism? Excellent contrast — No embolism MEI+ 40 MEI+ 55 Increase both window center and width such as in an preset angiography media administration confidence noise from high-kV images CkeVTv•10no O keWMono O keVTv•10no Protocol 3 = adding iodine maps Best in combination Tools window Tools Gre, chant et al, Investigative Radiology 2014 Grant et al, Investigative Radiology 2014 Weiss et al. Invest Radiol, 2016 Albrecht, Meier et al. Clin Radiol, 2015 Schoepf AJR, 2016 1 Albrecht, Wichmann et al. Investigative Radiology 2016 Leithner, Schoepf, Albrecht, Investigative Radiology 2017 Tools -30 -300 -500 Ratio 200% 100% 40 1225 pu 1226 pu pu
- pulmo
- lung
- PE
- embolism
- CTA
- perfusion maps
- defect
- ctpa
- perfused blood volume
- pbv
- vmi
- tbde
- twin beam dual source
- dect
- dsct