Neuro Thoracic Abdominal Abdominal Cardiovascular Pediatric SAFIRE Sinogram Affirmed Iterative Reconstruction Answers for life.
SAFIRE * (Sinogram Affirmed Iterative Reconstruction) * The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. Please note: the term Sinogram Affirmed Iterative Reconstruction will be substituted with the abbreviation SAFIRE throughout this brochure.
CT Vision Siemens CT Vision Today s reality The justification for the existence of the entire medical industry is, of course, better healthcare for all patients. But the realities of clinical practice often make this simple-to-understand goal quite difficult to realize: stay within budgets, reduce hospital stays, speed up time to diagnosis, and deal with personnel issues while maintaining high clinical standards and volume/throughput. At the same time, patients demand better and faster results. Our approach In order to meet our share of responsibility in addressing these challenges, Siemens, from the earliest stages of research, product development and design, relies upon the advice and recommendations of external medical experts to determine our focus and this focus has been on the needs and demands of our end users. Over the years, this focus has been finetuned in four key areas: to lead technological and medical advancement to maximize workflow efficiency to make state-of-the-art CT affordable to set the standard in customer care. Our vision As a partner of our customers, we create CT innovations, that lift clinical practice to a next level of excellence and enable wide access to better patient care. We believe that even the farthest technical horizons are temporary and can be surpassed with consistent dedication to improved healthcare. This visionary 4
approach, backed up by the by far largest R&D budgets in the healthcare industry, has made Siemens the undisputed innovation leader in CT over the last 35 years. And our ambitious global team continues to set the trend in an always changing environment, providing Answers for Life. Leading patient care More than 1.500 institutions worldwide have already decided to bring patient care to a new level by utilizing the fascinating capa bilities of the SOMATOM Definition AS and the SOMATOM Definition Flash. Minimizing patient exposure in every scan, plus offering new dimensions in CT imaging brings them to the forefront of patient care. Patient-centric productivity Fuelled by the new and unique features of FAST CARE, the new SOMATOM Definition AS and the new SOMATOM Definition Flash now lets customers unleash the full potential of their resources. And now Siemens reinforces even more these scanners in regards to dose protection, with the introduction of another low dose solution that will allow scanning at lower dose levels than before. Its name: SAFIRE*, the first raw-data-based iterative reconstruction. Now, for the first time, raw-data will be utilized in the iterative reconstruction process as you can further read in the following pages. Siemens CT Vision SAFIRE* Dedication to Low Dose Methods of Iterative Reconstruction SAFIRE* Improvements Clinical Cases Neuro Imaging Thorax Imaging Abdominal Imaging Cardiovascular Imaging Pediatric Imaging SAFIRE* for Your Scanner 4 6 8 10 16 20 20 24 26 28 30 32 *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. 5
SAFIRE * Iterative reconstruction Because at Siemens, dose reduction has continued to be given top priority, assuring both patients and medical personnel the best in medical care with the least possible risk, we can now introduce another low dose solution. Once again Siemens has set the benchmark on low dose imaging with the introduction of the first raw-data-based iterative reconstruction. For quite some time, iterative reconstruction has been heavily discussed in the CT community as a highly promising method to achieve significant dose reduction without compromising image quality. Essentially, iterative reconstruction introduces a correction loop in the image generation process that cleans up artifacts and noise in low-dose images. After the initial reconstruction using traditional filtered backprojection, synthetic measurement data are calculated from the image (in the so-called image space), as if the image had been the measurement object in a CT-scan. These new data are compared to the actually measured raw data, and a correction image is calculated. But until now, the implementation of this method for clinical practice was limited as this was very time-consuming and the computational power required for clinical practice was not yet available. But now, Siemens actually shifted into a higher gear and introduces SAFIRE*. For the first time, raw data (which are often also called sinogram data) are actually being utilized in the iterative image improvement process. With this, SAFIRE* can achieve a radiation dose reduction of up to 60% or improved image quality (contrast, sharpness and noise), even surpassing the already impressive image quality realized with IRIS Siemens entrance in the world of iterative reconstruction launched 2009. This amazing achievement resulted mainly from two measures: First, the algorithms used in the iterations were redesigned to make them more efficient, and second, new image reconstruction systems were developed *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. 6
with sufficient power providing the computational means required for the complex calculations. In a nutshell, SAFIRE* allows up to 60% additional dose reduction that can be achieved in a wide range of daily routine CT applications. With this, the average dose for all Siemens standard protocols can be reduced below the natural background radiation of 2.4 msv** in 3 out of 4 cases. Dedication to low dose The number of exams worldwide is growing, not only because CT offers extremely high diagnostic certainty but also because the acquisition method is simple and results are reproducible. And because of CT s versatility, it has become a standard examination in medical facilities around the globe and accordingly contributes to a significant amount of overall radiation exposure in the entire population. Because of this factor, all CT facilities and vendors assume a heavy and unavoidable responsibility to minimize radiation and maximize safety for their patients. At Siemens, we see it as one of our core responsibilities to provide medical institutions with solutions that enable them to further lower the radiation dose without compromising image quality. For this reason, we have, from the beginning, developed many significant products and protocols that follow the ALARA principle to reduce radiation dose to the lowest possible level. This desire for as little radiation exposure as possible lies at the heart of our CARE (Combined Applications to Reduce Exposure) research and development philosophy. Over the years, Siemens has been highly successful in integrating many innovations into the Siemens scanners that significantly reduce radiation dose in comparison to other systems available on the CT market. Now, Siemens again introduces another innovative CARE feature SAFIRE* to give our customers every means to minimize dose and consequently take best care of their patients well-being. **Valid with the current protocols currently work in progress 7
Low Dose Dedication to Low Dose With SOMATOM scanners, saving dose starts right at the point where image data is acquired the Ultra Fast Ceramic (UFC) detectors enable up to 30% dose reduction. X-ray The tube current is switched off within a certain range of projections, minimizing direct exposure to the hands during CT-guided interventions, and saving up to 70% of dose. As Dual Source CT images the heart twice as fast, the dose necessary for excellent cardiac imaging can be applied in less than half the time, enabling up to 50% lower dose at typical heart rates. UFC X-ray off t Light X-ray on 1994 1997 1999 1999 2002 2005 CARE Dose4D UFC Adaptive ECG- Pulsing HandCARE Pediatric 80 kv Protocols DSCT Dose Saving Up to 68% Up to 30% Up to 50% Up to 70% Up to 50% Up to 50% *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. Fully automated dose modulation adapts dose to each individual patient in real time, reducing dose up to 68%. The heartbeat-controlled dose modulation applies the exact dose necessary to collect all data during the diastolic phase, saving up to 50% dose. Enables up to 50% dose savings in pediatric imaging by utilizing dedicated low kv child protocols that allow an individual adaptation of the patient dose to small sizes of pediatric patients. 8
Its ability to dynamically block clinically irrelevant pre- and postspiral dose significantly reduces the possibility of over-radiation, saving up to 25% of dose. Enables dose-neutral Dual Energy imaging by blocking unnecessary photons of the X-ray energy spectrum. Reduced dose-sensitive bodyregion exposure up to 40% by virtually switching the X-ray tube off for a certain range of projections. First automated, organ-sensitive voltage setting to optimize contrast-to-noise-ratio and reduce dose by up to 60%. Dose Shield Selective Photon Shield X-ray low 70 kv 80 kv 100 kv 120 kv 140 kv Dose Shield 80 kv Attenuation B 140 kv Attenuation A X-ray on 2007 2007 2008 2008 2008 2008 2009 2010 2010 Adaptive Cardio Sequence Adaptive Dose Shield Flash Spiral Selective Photon Shield 4D Noise Reduction X-CARE IRIS CARE kv SAFIRE* 1 3 msv Cardio Up to 25% < 1 msv Cardio No dose penalty Up to 50% Up to 40% Up to 60% Up to 60% Up to 60% < 1 sec Tube 1 Tube 2 Vol Image data recon Image correction Raw data recon Image data recon Image correction An intelligently triggered sequence that shuts off radiation in the systolic phase, thus routinely enabling low dose cardiac imaging below 3 msv. Enables dose values down to under 1 msv in everyday routine using maximum speed and minimum overall exposure time. Enables long-range dynamic scanning with up to 50% lower dose utilizing an intelligent image noise suppression algorithm. Multiple iteration steps in the reconstruction process eliminating noise, therefore enabling up to 60% dose reduction. The first raw-data-based IR reduces dose up to 60% in a wider protocol spectrum or allows for a superior image quality. 9
Introduction Methods of Iterative Reconstruction Standard FBP Theoretical IR Statistical IR Raw Data Space Image Data Space Raw data recon Raw Data Space Image Data Space Raw data recon Compare Exact image correction Full raw data projection Raw Data Space Image Data Space Raw data recon Compare Basic image correction Basic raw data projection Ultra-fast reconstruction without iterations Well-established image impression Limited dose reduction Dose reduction or image quality improvement Well-established image impression Very time-consuming reconstruction Dose reduction Fast reconstruction with few parameters Unfamiliar and plastic-like image impression 10
IRIS SAFIRE* Raw Data Space Image Data Space Compare Image data recon Master recon Exact image correction Raw Data Space Image Data Space Image data recon Compare Raw data recon Compare Exact image correction Full raw data projection Dose reduction or image quality improvement Well-established image impression Fast reconstruction in image space More powerful dose reduction than image-based methods Well-established image impression Superior image quality Fast reconstruction in image and raw-data space and improved workflow with variable settings *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. 11
Introduction Methods of Iterative Reconstruction Filtered back projection Dose reduction with CT has been limited by the filtered back projection (FBP) reconstruction algorithm, which is typically used by conventional CT scanners. When using this reconstruction of acquired raw data into image data a trade-off between spatial resolution and image noise has to be considered. Higher spatial resolution increases the ability to see the smallest detail; however, it is directly correlated with increased image noise. Siemens Standard Weighted Filtered Back Projection (WFBP) As Siemens has been dedicated to low dose CT for decades, we have already enhanced the conventional FBP so that our standard protocols already achieve significantly lower radiation doses compared to other conventional, but eventually younger CT scanners. This is mainly realized by continuously adding dose saving features where applicable. Theoretical iterative reconstruction Iterative reconstruction approaches allow decoupling of spatial resolution and image noise. In an iterative reconstruction, a correction loop is introduced into the image generation process. Synthesized projection data are compared to real measurement data in an iterative manner: the update image is refreshed by a correction image and prior knowledge is imposed onto image data. The application of prior knowledge smoothes the image within homogeneous regions, whereas contrast edges are preserved. In a theoretical iterative reconstruction, the physical properties of the scanner s acquisition system are taken into account during the calculation of synthetic projection data. But up to now, the introduction into clinical practice for CT was handicapped due to the extensive demand for computational power required for the modeling of the scanner. Statistical iterative reconstruction Although this simple model is significantly reducing the computational efforts for iterations compared to theoretical iterative reconstruction, aggressive noise reduction may cause a noise-free appearance with unusually homogeneous attenuation, decrease in sharpness (irregular edges) in the images which leads to a blotchy and pixelated image texture and quality. The noise texture of the images differs strongly from standard filtered back projection reconstruction that limits the clinical use as the users have to get used to working with unfamiliar image impressions. 12
Iterative Reconstruction in Image Space (IRIS) In 2009, Siemens introduced its first approach to iterative reconstruction to intelligently solve the trade-off between reconstruction times and image quality. Instead of reducing the amount and complexity of corrective models to gain reconstruction speed, Siemens developed a new method to accelerate reconstruction by applying the raw data recon struction only once. During this newly developed initial raw-data reconstruction, a so-called master volume was generated that contained the full amount of raw-data information but still at the expense of significant image noise. The following iterative corrections were then consecutively performed in the image space, cleaning up and removing image noise without degrading image sharpness. With this approach, IRIS could improve image quality and achieve dose savings of up to 60%. Sinogram Affirmed Iterative Reconstruction (SAFIRE*) With SAFIRE* Sinogram Affirmed Iterative Reconstruction Siemens introduces the first raw-data-based iterative reconstruction. This can be achieved with further enhanced algorithms, but specially by using the now available hardware capacities improving the iterative reconstruction image process. In addition to the well-established approach of IRIS, the data is also re-projected in the raw-data space allowing for corrections of geometrical imperfections of the initial reconstruction. Potential artifacts that may occur with any system using the FBP will also be corrected. This allows to additionally validate (or affirm) the images with the measurement data. The detected deviations are again reconstructed using the WFBP, yielding an updated image. This loop is then repeated multiple times and in each iteration a dynamic raw-databased noise model is applied allowing for reduction of image noise without noticeable loss of sharpness. This optimization process thus makes even better use of the diagnostic information contained in the raw data. With this, SAFIRE* also allows to reduce dose by up to 60%, but for a much wider range of applications. Or instead, SAFIRE can deliver a superior image quality, even surpassing the already impressive image quality achieved with IRIS. *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. 13
Introduction Methods of Iterative Reconstruction Plain FBP Siemens WFBP Theoretical IR Routine abdomen scanned at 50% of normal dose resulting in limited image quality with high noise. Siemens WFBP already reduces noise compared to a Standard FBP therefore improving the standard image quality. Theoretical iterative reconstruction significantly reduces the noise, therefore improving the image quality. 14
Statistical IR IRIS SAFIRE* Statistical iterative reconstruction reduces the noise as well, however the plastic image impression might be unfamiliar to the user. IRIS maintains a well-established image impression and in addition significantly reduces the noise, therefore improving the image quality. SAFIRE* delivers superior image quality with well-known image impression. And it also allows to significantly reduce dose for a wide range of clinical applications. *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. 15
How it works SAFIRE * Improvements Superior image quality Every iterative reconstruction starts with a filtered back projection (FBP) as the initial reconstruction step. With the introduction of Siemens WFBP the image quality was increased significantly. As you can appreciate in the images on the next page, noise could be significantly reduced up to 35% from the typical FBP used by conventional scanners compared to Siemens standard WFBP used in all SOMATOM scanners. Logically, starting with Siemens WFBP at a better level of image quality, we are able to achieve an improved image using IRIS or a superior image quality by applying SAFIRE*. SAFIRE*, the first raw-data-based iterative reconstruction, is able to overcome the compromise between sharpness and noise and to improve image quality while providing a significant radiation dose reduction. The improved superior image quality is achieved by newly added iterative steps also in the raw-data domain. Dose reduction by up to 60% The impressive dose reduction with SAFIRE* can be achieved while maintaining a superior image quality, because in addition to the well-established approach of IRIS, the data can now also be re-projected in the raw-data space, in order to additionally validate (or affirm) the images with the measured data whenever needed, thereby reducing image noise even more than previous methods. This allows the user to scan at lower dose levels (by reducing the eff. mas settings) than with conventional protocols, which would eventually lead to a noisy image impression if not reconstructed with SAFIRE*. And now we are even able to reduce the dose not only in specific protocols, but in a much wider range of body regions. This allows us to have 72% of all protocols** with an effective dose of less than 2.4 msv.*** * The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. ** Current status work in progress *** Taking into consideration a typical scan length for each individual body region 16
Plain FBP Siemens WFBP IRIS SAFIRE* 35% less noise comparing with Plain FBP 30% less noise comparing with WFBP Up to 55% less noise comparing with WFBP and 70% comparing with Plain FBP 26.8 HU 17.6 HU 12.3 HU 7.8 HU 17
How it works SAFIRE * Improvements Preview image 1 Improved workflow for clinical practice Furthermore, SAFIRE* is customizable and enhances workflow. It s customizable as there are now five different types of image impression available for selection. Starting from level one, each of these five images has then less noise than the previous. The user can now select his preferred image quality impression from this set of five preview images before reconstructing the whole dataset, thus saving time and enhancing workflow. Take a thoraxabdomen case for example. The image impression will not be the same in both body regions. So with the possibility to select an image from the abdomen to set the standard for the desired image impression, unnecessary reconstructions are avoided hence speeding up the workflow. *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. 18
Preview image 2 Preview image 3 Preview image 4 Preview image 5 19
Clinical cases Neuro Imaging Excellent gray-white matter differentiation CT is considered the initial modality for routine and advanced head imaging. Since the introduction of Siemens first commercial head scanner in 1974, we have continuously focused on delivering excellent head imaging quality on the entire CT scanner family. With SAFIRE*, the first raw-data-based iterative reconstruction, significant dose savings can be achieved while preserving a superior, well-known image quality. The images on the next page compare two different reconstructions. On the left you can see a reconstruction performed with the Siemens standard WFBP and on the right the same image now reconstructed with the newly introduced IR SAFIRE*. *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. 20
Standard WFBP SAFIRE* Standard weighted filtered back projection reconstruction, using an H31 kernel. This image nicely visualizes image quality achieved with SAFIRE*. You can appreciate the significantly decreased image noise without loss of resolution or gray-white matter differentiation. 21
Clinical cases Neuro Imaging Standard WFBP SAFIRE* Standard weighted filtered back projection reconstruction, using an H31 kernel. SAFIRE* reconstruction of the posterior fossa nicely visualizes the significantly decreased image noise without loss of resolution. 22 *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S.
Standard WFBP SAFIRE* Standard weighted filtered back projection reconstruction, using an H31 kernel. Another example that nicely visualizes the significantly decreased image noise without loss of resolution or gray-white matter differentiation achieved with SAFIRE*. 23
Clinical cases Thorax Imaging Benefits in clinical routine: One of the most frequently performed examinations in clinical practice includes the imaging of the thorax. SAFIRE* can help in achieving high dose reduction in all body regions. However, the greatest potential can best be seen in those areas scanned most often, such as the thorax, where by the pure number of exams the accumulated dose savings can be immense. The images on the next page show how SAFIRE* offers the above mentioned clinical benefits in daily practice for the patient, as well as the physician. *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. 24
Standard WFBP SAFIRE* Coronal image of the entire thorax using the Siemens standard WFBP reconstruction. Coronal image of the entire thorax now showing the impressive image quality achieved at 60% dose reduction when reconstructing with SAFIRE*. 25
Clinical cases Abdominal Imaging Up to 60% lower dose In the broad spectrum of diagnostic methods and equipment available today, CT has assumed more and more importance especially with abdominal imaging. As CT has become a standard examination for routine work and the number of exams worldwide is increasing, we at Siemens want to continue minimizing radiation and maximize patient safety. Now, with SAFIRE*, we are able to significantly reduce radiation exposure in these routine examinations, such as in the thorax region shown in the previous pages, while keeping outstanding image quality. The images on the right show a comparison of SOMATOM Definition Flash routine abdomen scans from the same patient. *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. 26
Standard WFBP SAFIRE* at 60% lower dose SAFIRE* with better low contrast detectability Coronal Abdomen pelvis reconstruction using Siemens standard WFBP. This image was reconstructed using SAFIRE* and 60% less dose than the image on the left. Here you can appreciate the powerful dose reduction while keeping the image quality constant. This image shows the outstanding image quality improvement from a WFBP achieved with SAFIRE* while maintaining original dose level. 27
Clinical cases Cardiovascular Imaging Improved image quality Cardiovascular diseases (CVD) are the leading cause of death worldwide. CT plays a steadily increasing role in the field of CVD imaging. Robust cardiac CT imaging requires highest diagnostic quality and lowest possible dose. Siemens has already decreased radiation exposure, while maintaining its excellent image quality to a routine and previously unbelievable less than 1 msv by using SOMATOM Definition Flash. However a better image quality can still be achieved by using SAFIRE* image quality improvement benefits. Or, when used in combination with other scanners, it also reduces significantly the dose. The images seen on the next page clearly demonstrate this potential. *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. 28
Standard WFBP SAFIRE* with better image quality This coronary image was reconstructed using Siemens standard WFBP. This image was reconstructed using SAFIRE* and a substantial improvement in image quality can be seen, specially in the soft tissue, while keeping the necessary image sharpness. 29
Clinical cases Pediatric Imaging Lowest possible dose: All patients benefit from reduction in radiation dose. However, there are specific patient groups, in which the reduction in radiation dose is of utmost importance. One of these patient groups is pediatrics. Anatomical and physiological differences between children and adults require special attention when imaging pediatric patients. Image quality requirements are different, because they have smaller body structures, which are more difficult to visualize in CT scanning procedures than the adult sized body structures. Also, higher heart rates and difficulties in cooperating during the scan can influence the final image quality. Adjustment of scanning parameters is important to meet image quality requirements and, in addition, it is essential to reduce dose to children because of long-term, higher potential radiation risks since they are more sensitive to radiation than adults. With SAFIRE* even more significant high dose savings can be achieved thus lowering even more the dose to these pediatric patients. The images on the next page show a comparison with the WFBP and SAFIRE* where an impressive dose reduction of 60% can be achieved. *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. 30
Standard WFBP SAFIRE* up to 60% dose reduction Coronal pediatric image reconstructed with Siemens standard WFBP. Despite the challenge of scanning pediatric patients, SAFIRE* allows to deliver excellent image quality at lower doses even in this patient population. 31
SAFIRE * for Your Scanner 32 *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S. SOMATOM Definition Flash Flash speed. Lowest dose.
SOMATOM Definition AS Maximize outcome. Minimize dose. 33
Earlier implementations of iterative reconstruction techniques already enabled preserved diagnostic accuracy at substantially lower radiation dose. SAFIRE * does this and much more, by providing brilliant depth, granularity, and texture to the CT image, thus enhancing every diagnostic detail. U. Joseph Schoepf, MD Professor of Radiology and Cardiology, Director of CT Research and Development Medical University of South Carolina, USA *The information about this product is being provided for planning purposes. The product is pending 510(k) review, and is not yet commercially available in the U.S.
On account of certain regional limitations of sales rights and service availability, we cannot guarantee that all products included in this brochure are available through the Siemens sales organization worldwide. Availability and packaging may vary by country and is subject to change without prior notice. Some/All of the features and products described herein may not be available in the United States. The information in this document contains general technical descriptions of specifications and options as well as standard and optional features which do not always have to be present in individual cases. Siemens reserves the right to modify the design, packaging, specifications, and options described herein without prior notice. Please contact your local Siemens sales representative for the most current information. Note: Any technical data contained in this document may vary within defined tolerances. Original images always lose a certain amount of detail when reproduced. Global Business Unit Siemens AG Medical Solutions Computed Tomography Siemensstr. 1 DE-91301 Forchheim Germany Phone: +49 9191 18 0 Fax: +49 9191 18 9998 Global Siemens Headquarters Siemens AG Wittelsbacherplatz 2 80333 Muenchen Germany Global Siemens Healthcare Headquarters Siemens AG Healthcare Sector Henkestr. 127 91052 Erlangen Germany Phone: +49 9131 84-0 www.siemens.com/healthcare Legal Manufacturer Siemens AG Wittelsbacherplatz 2 DE-80333 Muenchen Germany www.siemens.com/healthcare Order No. A91CT-23013-07C1-7600 Printed in Germany CC CT 23013 WS 11105. 11.2010, Siemens AG