CT Essentials Webinar Series 3 - Reconstruction Parameters Part 2 and Intro to CARE kV

Body on behalf of the Siemens Healthineers education team. I would like to welcome you to the next session of our City Essentials Webinar series. This week we're covering reconstruction parameters Part 2 and an introduction to care technologies. If you have any questions throughout the webinar, please type these on the right hand side of the screen and we will answer as many as possible at the end, certificates will be available through PP Connect within the next week and you will also receive an email link to the recording by tomorrow afternoon. I will now hand over to Andrew Pan, one of our city application specialists. To begin this session. Thanks Mel. Hello everyone, thank you for joining me today. So last week we covered the standing parameters, fundamentals of the scanning parameters and we touched on some reconstruction parameters today that week. But I just want to finish it off and also introduced you some care technologies, more specifically care cavey. But let's get it rolling. So I just want to talk about the reconstruction process more. One of basic level. So what we want to do, I hope you can see this picture here, but as you can see you can see the raw data or sinusoidal wave here and once we apply our reconstruction parameters we get our CT image on the right. Now I wanted to take a moment just to. I mentioned a couple of terminology discrepancies when we talk about raw data, so depending on what vendor you scanned on previously or what's the varying scanners that you scan on previously raw data might refer to two different things. Certainly with Siemens we refer to Raw data as the unprocessed information that comes from the detector channels, and it's more like more what we see here, so it's diagnostic nonclinical image. And what we're trying to do is we're trying to apply these parameters so that we can get this image now. Again, going back to terminology. Some sites, some scanning, sorry, will refer to raw data and thin data, but really for us in data is ultimately a reconstructed image and it has all these parameters essentially applied to them, but only with a thinner slice. OK, so that's just the discrepancy I want to get out of the way there, but. Last week I did mention that we want to spend some time on kernels. It is certainly something that people find a little bit difficult to understand, but hopefully we can cover that today so we can see the kernel here. Be 30 F. If this looks different to how you see it on your scanner, it's very likely that it's because you're on a different version. Probably more recent version, but really the capital B here refers to the kernel family, so this one first with body. This is the kernel group, which is fine noise. And this is the kind of scale, so we're going to talk a little bit about this figure here. OK, So what is the current? A kernel is essentially a. The convolution procedure that occurs during the image reconstruction process, which allows us to really enhance certain feature features of the image we want to produce without going into the physics part of it all. Essentially what kernel is like a digital filter, but the wall data port part passes through and through that it gets certain values enhanced and the features that enhances the sharpness of the image. So hopefully you can see the graph that I have in front of you there, but ultimately with the kernel we're trying to prioritize whether or not we want to smooth image or a sharp image. So referring to the graph, we can see that a low kernel value generally refers to a smooth reconstructed image, and as we go up the graph. We applied we're wanting a sharper image going up to you 90 now it's it's important to be mindful that when we are prioritizing sharpness that we are also increasing the noise index of the image as well. And that if we go further down into a smooth, the kernel were also decreasing the noise as well. And so clinically you should be able to appreciate that when you performing an abdomen scanner, reconstructed admin scan, you would. Ultimately want low noise because you want better low contrast resolution in your images. So when we apply kernel, it's very likely that we're playing a kernel between the 30 to 50 range here, which you know provides us with a healthy noise index level. But yeah, without going into the Facebook, we're going to continue on. So last week last week, as we did touch a little bit on slice thickness. But because it's such a big part of reconstructions, I thought we would go over it again in a little bit more detail. But when we're selecting a slice, a suitable slice thickness where essentially trying to balance between edge definition and noise, those two are ultimately kind of married together and neither one is right or wrong. It just depends on what we're trying to apply it in, what we're trying to achieve. So when we're looking at soft tissue abdomen scans we it's not uncommon for us to reconstruct at 5 millimeter by 5 millimeter series. And that's purely because of thick slice generally means lower noise, which helps in producing low contrast resolution in our image is what it's not good for. Thick slices was not good for is edge definition. Ultimately, it is going to be affected by a bit of partial voluming. Now again touching on. On it last week, partial Voluming is the weighted averaging of neighboring voxels to produce the image that we see. So if you see kind of blurring effect around around an organ that borders against another density, be aware that they most likely a partial volume artifact that you have there, but moving on to thin slices. Now if we're looking at really thin structures that we're looking at structures that change densities in the directions very quickly, like pictures, temple bones for example, we're going to want. In a thin slice. Now whilst the thin slice is going to have more noise in the image and it is not going to help with the low contrast resolution, likely we're going we're applying our thin sliced reconstructions to more high contrast anatomy anyways, but we really a thin slice gives us better edge detection or better edge visualization. It is going to give us better high contrast resolution and where it ultimately is going to reduce the partial volume artifact because it is going to weight average over a smaller slice. But here is a visual representation of. Varying sliced it misses on this cross sectional image here, so hopefully you can appreciate the image quality, but on 3 millimeters slice there we can see that the image is being polluted by quite a lot of noise and you can appreciate that through all the grain more the speculated appearance there on the slice, whereas when we got in 10 millimeters slide we can see that especially in the liver tissue we can see that it's more homogeneous. It's lot better with low contrast structures and it. Ultimately doesn't have any noise. Sorry it does have noise, but it's not as prominent in this slice here, but I just wanted to kind of speak further to that point here, but with the thinner slice you can see when we're talking about edge detection that you can definitely. We definitely visualized the rugal folds of the stomach a lot nicer than we can see here, and it's coming over here in the stomach. Here you can see kind of blurring effect here, and that's because of the partial volume in artifacts and it's averaging a lot of the box neighboring boxes to create create this. Blurring out the fact as well, OK? Moving on and this is just an example that we made earlier about Petra Temple Bones or looking at the items on the thicker slide. The five 5 millimeter slice there we can see that the. The C Noid Ridge in the lesser greater sorry the lesser speedwing. It's all kind of blurring together. We can also see that in the frontal sinus there should be a little bit. Having appearance latest there, that's not that's quite able to find. You can see that it's blurring there. That's because it is a sticker slice of cake. As there is quick change in density in the Z direction, but is averaging across. But when we move into the one millimeter slice, we can see that there is better spatial resolution. It's quite evident when we're looking at the mastoid air cells the way we can differentiate between the individual mastoid air cells. And we have better edge detection on the sphenoid regions as well, so. Clinically, you can always create series with varying slice thicknesses and just see how the appearance looks myself. Yeah, now This is why I want to describe talking a little bit more about window windowing, an LCD images. So in the very first presentation in will be discussed user interface. So in this last week we were talking about scan parameters we were discussing how attenuation coefficients help us to produce CT values, and so going back about that a little bit more. When we scan it to the object with X Rays, if we can calculate all the X Ray projections, then we should be able to calculate the attenuation coefficient of that structure, which ultimately leads to us being able to determine the see T value of that structure. But we in our industry we typically measure in Hounsfield units and in order to do that we use a see T that we take all those DT values and we standardize it to the attenuation water, and so there's ways towards 0 here. And then we can see all the Hounsfield unit based on the on the instructions here and how they are relative to water. And so this Y axis is the House field units OK? But why do we have to window? Why can't we just assign a particular grade level to 3000, 2009, 999, so and so forth? The reason why we have to do windowing is because our eyes are human. I can only distinguish between 30 to 40 grayscales at best. So of course that is user dependent. If you have if you are visually impaired in any way, that's going to degrade your ability to distinguish between varying greyscales and so that's why we need to make sure that our we're reconstructing these. Images appropriately to apply our grayscale abilities to the image. Sorry, what parameters do we play with when we when we talk about windowing? So the two parameters that we traditionally talk about is window width and window center window, which is the density range represented within the grayscale, whereas the. Windowing center refers to the middle. Yeah, now windowing center can and window level level is used interchangeably. So if you knew to see T and here window width window. Sorry window center window level generally referring to the same thing, OK. And when it comes to Windows Center, there is a rule of thumb that you want. You might want to consider when you're building your protocols, and that's to set the level at a point which is roughly the same value as the average Hounsfield number of the tissues of interest. So for example, we go back to this graph here, and we can see that if we were scanning an abdomen scan and we want to represent all these organs that we're likely to see, then we would likely want to set our level somewhere in 4440 to 60 range there. OK? Quite common that set at 50. OK, but I did have a question for everyone. Just kind of trying to add some engagement here, but if the window width is set at 300 then a range of 300 different household units will be seen on the image. But what structures are included? And I'll give you a moment to answer that question. OK, we gotta. So the answer is, it really depends on the sensor set. So think about the center as it has positional information whereas width is more like a range. So without the sensor information, we don't really know where we're going to apply this window with the case, so just that you require both information and so if we were to set the center at zero, the range will be between one positive 150 to negative 150. Alright, and so this is just a visual example of us narrowing the window with versus having a broad window with. So as you can see, and I'm assuming the sensor shares somewhere in 59, but if we narrowed the window with that we can see that we get much better high contrast than on this image purely because we're applying algorithm Gray scales that we can see to a narrower width. So to narrow structure whereas. When we look at this side, we can see that there is. Not much differentiation between minor neighboring densities and so this is how this is the narrow with window with is likely to be what you're more closer to. What you reconstructed As for this particular examination, just be mindful that the difference between the two is that you can see the stomach of the border lot nicer here than here, so this one still requires quite a bit of tweaking in my opinion, But that's neither here or there. OK, moving. Oops, sorry. We that pretty much completes our reconstruction parameters slides. Now I want to introduce you to now going back to scanning parameters, but really introducing you to how Siemens implements optimization of cavey. So with care just to begin with, just breakdown the acronym or CARE really stands for, so it's combined application to reduce exposure and so you'll find it quite a lot of care licenses in our products there, so we have care dose 4D as well, which refers to those modulation. And we will talk quite a bit and in detail about that next week. But we also have K contrast and whole bunch of things so. What is KKV? V is the optimization of the cavi parameter. To minimize patient dose as well as and maintain image quality. But what does that really mean? It means that by turning it on, we're allowing the scans automatically. Adapted cavey to the patient size and the examination type. And that's how it achieves those optimization and image quality optimization. Some of the benefits so. Once on, the benefits is that we're able to control allow the scanner to control the exposure and also achieve a more consistent image quality from patient to patient, and ultimately to do that it is trying to optimize the signal to noise ratio to the desired image quality, and also what's good about caves that wants turned on. We don't have to adjust the Ma's to get the signal to noise ratio. I'll show you a little bit later, but the sliding bar, but when you have care, dose 40 turn on that. All kind of guesswork out in the background. So with care cavey, there are three different modes, and with of course. It depends on your clinical use case. You might want to have on semi on or use my want to have it off entirely and have more control over what your exposure will be. But First off, we haven't, as of now, for the people who are looking at this screen and thinking back to their examination card on there scanner and wondering why they don't have the same appearance on their screen. Chances are what we mentioned in number session one that depending on what scanner using and depending on your click the configurations of your scanner, your examination screen may look different from site to site. OK, so just be mindful that here Cavey might not be on your scanner. It might very well be honest. So when we turn it off and we click that true button there we get this screen here. Now this screen refers to the definition of image quality we touched on earlier about what quality reference image is really what referencing really means and Siemens and it refers to us having a particular image quality for a reference patient at the size of 75 kilos. So it's always going to be at that reference patient. So when we have care cavey turn off, everything stays the same. So we have to select the cavi that we want the quality reference in May is that we want. An the effective MA is will not be adjusted if we change the cavi. OK, so that's kind of the differentiated between often semi versus off versus semi an on. Look, but if we turn it on. You will notice that the the definition that that panel where we can define the image quality now allows us to engage with the slider bar. Now we have the reference reference cavey similar concept of quality reference Ms, but what's more interesting is the sliding bar. So when we have the sliding so when we turn on kid care cavey Ascentia Lee we are asking the scanner to optimize the OR actually adjust the cavi for the image that we want to optimize for. So when we look at the slider bar we can see a syringe there with an X that refers to non contrast studies. Most burn. Then we have soft tissue with contrast. And then Lastly we have. Vascular place so your tradition angiogram study OK. An ultimately from the left side of the bar were kind of trying to control the noise. So traditionally this is a higher K VI setting. But as we go through and kind of going through a more high contrast structures and mediums were going to be dropping the kavian also increasing a little bit of a noise. OK so that's kind of how that works, but what you want to do when you turn it on is you want to adjust want to slide. Move this slider to what we want to optimize for. And then yeah, and then our effective images will adjust for that as well. Alright. So I'm just gonna read this one out. Went on, selected the caving entry on the routine card is dimmed. Meaning over here you can't really. You want 'cause you turn on cavey. You're not really trying to enter in one manually, you're trying to get the scanner to decide one for you based on total drama. All the information we do have. Yep, in the dose will optimize for non contrast studies. Soft tissue with contrast and vascular but also grow as well. Alright, but we also have the option to turn this care cavey onto semi Mode now semi mode. Is when we can make we can determine what cavey the scan should be performed at, but you can notice that we can still adjust this slider here, so we are still making the argument that we want the some some level of optimization. So when we move the slider any particular way, but we changed the cavi. The scandal affected the change. The effective MA is to ensure that we are achieving the correct signal to noise ratio for any given setting. Some of the use cases you would use the semi option would be if you were going to do a follow up scanner review scan of the patient with the lesion and if you get a referral. This is scan at the same cavey. Just be mindful that Hounsfield units RKV dependent if you increase the cavi for any given structure of the House full unit will decrease simply because the beam now has a higher penetrated strength and if you. Of course vice versa. If you decrease the cavi along the same structures will have an increased house for dinner. OK, so just be mindful of that physics there. But yeah, if we looking to control the cavey. Effective images will compensate to try and maintain the same signal to noise ratio OK? And this is just a. Have a. I mentioned what we just discussed, so you have the freedom to select the cavi you want and effective images will be then calculated and this just goes on to really demonstrate those use cases there. So again, clinical studies, follow-up scans demands the same cavey settings as the prior scan, but again, also it can also be useful in determining what will achieve the lowest scan dose and so I'll give you a bit of an example here. So as we can see, we've adjusted the so if we can take a look at the 1st. At the top image there we can see that we will use this as a control with The Cave 120, but with the semi feature turned on and we reduce the cavi down to 80 we can see that in order to maintain the same signal to noise ratio is ultimately increasing effective MAS there OK, but going back to the original scanning session that we did last week, heavy does have a much more contributing effect to overall patient dose and so it's obviously represented there OK? But just be mindful of how US changing one parameter can affect the other. But really, going forward you stop yes. So again, this is going to. This is just discussing the this bar here. This little pop up that occurs when we could still choose button there and essentially it all is referring to image quality. OK, because we do have that reference patient, we're making the argument that we want to achieve a similar image quality that we were at Siemens was able to achieve with 75K patient optimized for this organ. In this is some of the workflow cases around care cavey do not change the cavi depending on the patient size. It's really the position of the those optimized optimization slider that's important. So maybe in previous scans or maybe more historically, I should say if you had two cardiac protocols, 100 KB for slim patient and 1:20 K view for an obese patient in regarding the in regards to care cavey. We will take the .120 KV protocol and KK V will change to a lower KV when possible, so that's kind of the more appropriate way of understanding kavian how you should adapt it. And a good yeah. Now going into how we can change the settings around KK V Now traditionally scan is going to have a range of 80KV2140KV, but of course that range of KV is not suitable for a lot of scans, right? You want to kind of limit? You want either limit it to a low end or high end so with. When we go into scan protocols system, we can actually change the minimum and maximum KV range that the scanner is allowed to select for any given protocol. So we have a couple of examples here. For vascular studies you don't want to scan with one 40K V again with quite like vascular studies because the introduction of contrast medium creates a high contrast differentiation, differentiation around the surrounding tissue. We can limit this maximum KE Vita 120 so that the scanner would never. Choose 140 for example, and vice versa with the head. You know we don't want to scan at a low 80KV. Obviously that's not going to help us with locally, locally owned shop structure visualization, and so we really want to set that minimum cavey to about 100 at the lowest level. But that really concludes my introduction to care kavian finishing off reconstruction parameters for those who have to go. Thank you for joining us, but I'll be taking on questions if anyone has anything. OK, so it looks like we do have a. So I have a question here. Does KK we rely on AP and lateral to programs. So with the to programs. It depends on the structure that we're looking at. Traditionally with cranial work we're looking at natural. We're looking at natural to programs, whereas we're looking at chest and abdomen switch. Additionally, would rely on the a piece OKKV is more taking that information and apply and optimizing it correctly, but it's more the dose modulation that we require. We would need that a program to be corrected. The anatomy that was scanning in. So if you're looking at spines traditionally all we would need is lateral to program. Of course you can include the AP for planning purposes, but yeah, it depends on what anatomy we're looking at. the AP or natural becomes more relevant in terms of modulation and optimization. I hope that answers your question. How does I shoot effective dose? I'm. So I should, I'm assuming that you're referring to X care where it's angular modulation where. It turns off the exposure in the anterior portion. Are you can have X care on but. How to fix dose it should be dose neutral from what I'm aware it's more than it's controlling the applied those to the anterior organs. So I hope that answers your question. OK, I think we'll leave it at that. OK, so next week we're going to be touching on care dose 4D, which is the Ms modulation component of our themes technologies. Hope you can join us for that. And yeah, I'll see you next week, but thank you for joining us.

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Selecting Slice Thickness Image Display - Windowing Image Display — Windowing Healthineers • Slice Thickness On On Off Semi Semi: better edge definition 1m ge definition poorer edge definition Selecting a suitable slice thickness is a balance between edge definition and noise e Initiono mage ua lty Definition o Image Quality e Initiono Image Qua lity Definition of Image Quality 5 mm Slice 1 mm Slice Workflow: The range of CT density values is defined from -1000 to +3000, but Image quality is based on the following: Semi: semi Semi 3000 +3000 Question: If the window width is set at Gray scale Broad Window Width Narrow Window Width: Broad Window Width: 30 mm Slice 3 mm Slice 10 mm Slice Narrow Window Width Scan Protocol Ass. cant. W e Initiono mage ua lty Definition of Image Quality Hounsfield Blood Sharp When "On" is selected the kV entry on the routine card is dimmed. The kV range can be set (min. & max. kV) in Scan Protocol Assistant. U90 Slice Liver 50 mm Acq. 128 xo.6 mm Semi: Semi +150 -150 -100 • Because of their mutually offsetting effects Rule of thumb: the human eye can distinguish only 30 - 40 gray scales at best. 60 3000 50 40 10 Questions? 210B 120 CARE CARE Dose40 CAREkV On 120 unit Tumor CT Essentials Webinar display 300, then a range of three hundred different Hounsfield units will The best suitable kV will now be chosen by the system. CARE Dose4D CAREW Ott Quaityref_mAs 210 ± Ref mAS 210 ± Ref kv Do NOT change the kV depending on Patient (size), the position of the Pitch QualiWref,rnAs 210B Ref kV Quality ref rnAs 210B Ref kV Quality ref, rnAs 210B Ref kV Automatic kV adaptation to the patient's size and the Spleen CARE Dose4D CAREkV CARE Dose4D CARE kV 120 Set the level at a point CAREDose4D CARE kV CAREDose40 CARE kv CARE Dose40 CARE kv CAREDose4D CAREkV Oualiryref mAs 210B Ref.kV Oualiryref mAs 210 d Ref. W Oualiryref mAs 210 d Ref.kV CARE Dose4D CARE kv Ref. kV Slice 50 mm Acq 128 x 06 mm 120 be seen on the image. dose optimization slider is important. Eff. mAs Ett mAs Eff mAs Direction Craniocaudal 210 120 White You have the freedom to select the kV you want and the eff mAs will You have the freedom to select the kV you want and the eff. mAs will high noise low noise Dose saving optimized tor Dose saving optimized tor: Dose saying optimized for Dose saving optimized for: saving optimized tor Cose saving optimized tor Ett mAs Eff mAs kV Dose saving optimized for 120 10 Bladder Session 3: 120 A Pitch Eff. mAs kV 3 different modes for Care kV Quality ref. mAs (CARE Dose4D) Optimisation of kV to minimise The dose will be optimized for: Dose saying optimized for. Dose saying optimized for: Lung Window A thick slice A think slice Organ characteristic: Abdomen Mediastinum Window Ett mAs 93 What structures are included??? Organ characteristic Abdomen Or an characteristic Abdomen Dose saqng optimized for. Dose saqing optimized for. Dose saying optimized for. Dose saving optimized for. then be calculated. Eff mAs Eff. mAs 210 120 For example: better low contrast resolution kV CARE kV enables optimised dose while providing optimised 120 same value as the Cases: Position of the dose optimization slider Non contrast scans Or an characteristic: Abdomen Organ characteristic: Abdomen 14_19 rnGy mGy•cm mGy 30 70 120 50 210 80 CAREW on CAREkV on Water means: Intro to CARE: CARE Organ characteristic Abdomen Organ characteristic: Abdomen I. Past: Two cardiac protocols 100 kV for slim patients and 120 kV for obese poorer edge definition better edge definition Window.„ Window 70 120 image quality. Soft Tissue with contrast scans Off average HU number of 631 DU': 6.31 DU': 631 DLP: 1356 Tools Image Cases: Semi patients. For vascular you don't want to scan with 140 kV (set max. kV to 120) Eff mAs Ef mAs kV center C width W width - Vascular scans partial volume artifacts Scan bime Scan bme Scan start Start button Scan start Scan time 515sB Scan time Scan time Scan start Scan start Stan buron Scan start Start Scan start Start button Rule of thumb: the Smoot I. Fixed kV is desired in combination with the appropriate mAs value. Definition of Image Quality Semi 70 50 120 10 30 image quality Now: Take the 120 kV protocol and CARE kV will change to a lower kV Organ characteristic Abdomen Organ characteristic: Abdomen Qualityref_mAS 210B Ref 120 210B 120 210B Ref A/ 120 Reconstruction Reconstruction Parameter$% Rotabon tirne Rotabon time RotaDon tirne Rotation time -100 That depends on the center set. If the center Noise Nonse Benefits: The CT value of water is O and air - when possible. (e.g. clinical studies, follow-up scan demands the same kV setting tissues of interest. Scan time Scan start Scan start Start button 2sd Delay Language German Mamma Scan start Start button Move the dose optimization slider to the desired position - Set dose optimization slider at correct position 2sd Semi: Semi Delay Language German For head you don't want to scan with 80 kV (set min. kV to 100) low High Ref kv Black high noise 120 1000. The relative values of the as the prior scan) 05 s A Rotation time Rotabon tirne API • Optimised Exposure Dose saving optimized for Dose saving optimized tor None Noise Nonse is set to "O", then the range displayed would be from -150 to +150. Narrow window width: Narrow Window Width: Narrow Window Width Rotabion time (mouse or arrow keys) Next Week: CAREDOSE4D API None Broad Window Width: Broad Window Width 2. When customer wants to decide himselfto change from higher to lower kV, 2. When customer wants to decide himselfto change fromhigher to lower kV, 2. When customer wants to decide himselfto change fromt5igher to lower kV, CT Windowing other tissues are calculated relative poorer low contrast resolution better low contrast resolution 2. I. Demonstrate which CTDI / eff. mAs values are taken when a 31000 +3000 2sd Dose saying optimized for Dose saving optimized for: Dose saying optimized for: Dose saqing optimized for. Dose saving optimized tor: Delay Delay' Language German German Language Eff mAs Eff. mAs 247 40 Definition of Image Quality • Optimised Image Quality Definition o Image Quality e Initiono Image Quality Fat take the default protocol and change CARE kV in Semi mode. Computational (or convolution) procedure occurring during image reconstruction which influences image High-contrast image, but structures to that of water A thin slice different kV settings are chosen. API None API Or an characteristic Abdomen Or an characteristic A Noise Nonse Minor density differences poorer edge definition contrast and noise structure. Window width (W): the density range represented Air Scan Lung • Optimised SNR & Introduction Tec,h outside that window range may be So, the window settings must be in accordance with the structures appear homogeneous and may provides the recipe for mathematical image calculation. Thinner slices give better spatial resolution for bone Two important steps to optimize customized protocols for CARE kV: better high contrast resolution better lowh contrast resolution means: The right mAs will be calculated Thicker slices give less noise & better contrast • No user calculations needed to get the right mAs values inadequately represented or within the gray scale. ref. mAs if desired. Eff. mAs are will not be adjusted if you change the kV! - Switch CARE kv on "ON" - Switch CARE W on "ON" to be visualized and lung structures be masked. detection ability for soft tissue (liver) partial volume artifacts less partial volume artifacts overlooked. - Set dose optimization slider at correct position Scan This is the so-called CT number in Hounsfield unit (HU) his is the so-called CT number in Hounsfield unit (HU) Window center (C): the center of the density range. O All rights Siemens Pacific Cluster. Author Department Pacific Cluster. Cluster. Unrestricted Siemens Healthcare GmbH, 2018 Unrestricted Siemens Healthcare GmbH, 2016 O All rights Siemens Pacific Cluster. Unrestricted Siemens Healthcare GmbH, 2018 unrestricted Siemens Healthcare GmbH, 2018 hcare GmbH, 2018 12 120 10 19 ENG