syngo MR E11 Operator Manual Ortho Answers for life.

Transcription

1 syngo MR E11 Operator Manual Ortho Answers for life.

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3 syngo MR E11 Operator Manual Ortho

4 Legend Indicates a hint Is used to provide information on how to avoid operating errors or information emphasizing important details Indicates the solution of a problem Is used to provide troubleshooting information or answers to frequently asked questions Indicates a list item Indicates a prerequisite Is used for a condition that has to be fulfilled before starting a particular operation Indicates a one-step operation Indicates steps within operating sequences Italic Is used for references and for table or figure titles Is used to identify a link to related information as well as previous or next steps Bold Blue Courier Courier Menu > Menu Item <variable> Is used to identify window titles, menu items, function names, buttons, and keys, for example, the Save button Is used to emphasize particularly important sections of the text Is used for on-screen output of the system including code-related elements or commands Is used to identify inputs you need to provide Is used for the navigation to a certain submenu entry Is used to identify variables or parameters, for example, within a string CAUTION Used with the safety alert symbol, indicates a hazardous situation which, if not avoided, could result in minor or moderate injury or material damage. CAUTION consists of the following elements: Information about the nature of a hazardous situation Consequences of not avoiding a hazardous situation Methods of avoiding a hazardous situation 4 Ortho Operator Manual

5 Legend WARNING Indicates a hazardous situation which, if not avoided, could result in death or serious injury. WARNING consists of the following elements: Information about the nature of a hazardous situation Consequences of not avoiding a hazardous situation Methods of avoiding a hazardous situation syngo MR E11 5

6 Legend 6 Ortho Operator Manual

7 Table of contents 1 Introduction Layout of the operator manual The current operator manual Intended use Authorized operating personnel Definitions of different persons 13 2 Measurement Overview of orthopedic imaging concept High throughput high-resolution imaging Advanced imaging techniques Dedicated orthopedic phased array coils Large Joint Dot Engine Knee Dot Engine Planning the examination and measuring the localizer 17 Adapting the examination to the patient 17 Starting the measurement of the scout 18 Changing the examination strategy subsequently Adjusting the slices and performing the measurements D examinations with integrated MPR planning Configuring MPR views (optional) 22 Assigning 3D measurements to the integrated MPR post-processing 23 Adding MPR views 23 syngo MR E11 7

8 Table of contents 2.4 Hip Dot Engine Planning the examination and measuring the localizer 25 Adapting the examination to the patient 25 Starting the measurement of the scout 26 Changing the examination strategy subsequently Adjusting the slices and performing the measurements Bilateral 3D hip examinations with integrated MPR planning Shoulder Dot Engine Planning the examination and measuring the localizer 32 Adapting the examination to the patient 32 Starting the measurement of the scout 33 Changing the examination strategy subsequently Adjusting the slices and performing the measurements D shoulder examinations with integrated MPR planning High-resolution fast 2D imaging Optimization with TSE sequence 37 Advantages 38 Optimizing echo time 38 Optimizing echo train length (ETL) 39 Optimizing fat saturation 40 Optimizing fat suppression 40 BLADE technique 41 Reducing examination noise 42 Reducing SAR for hip imaging syngo WARP: Imaging near orthopedic implants WARP: high bandwidth WARP: View Angle Tilting (VAT) technique WARP: Slice encoding for metal artifact correction (SEMAC) 47 8 Ortho Operator Manual

9 Table of contents 2.8 Isotropic 3D imaging D SPACE D TrueFISP D DESS MEDIC Image examples Parametric mapping with syngo MapIt T2 or R2 mapping with syngo MapIt T2 or R2 mapping: protocol parameters Examples in cartilage repair therapies (microfracture therapy vs MACT therapy) T2* or R2* mapping with syngo MapIt T2* or R2* mapping: protocol parameters Clinical use in cartilage repair therapies (microfracture therapy) Fast T1 mapping with syngo MapIt T1 mapping with B1 correction T1 mapping: protocol parameters Post-processing 3.1 syngo MR E11 Fusing biochemical maps and images Loading the data Loading the maps Loading the original images Optimizing the image display Visualizing the cartilage Saving and filming the images

10 Table of contents 10 Ortho Operator Manual

11 Introduction 1 1 Introduction In order to operate the MR system accurately and safely, the operating personnel must have the necessary expertise as well as knowledge of the complete operator manual. The operator manual must be read carefully prior to using the MR system. 1.1 Layout of the operator manual Your complete operator manual is split up into several volumes to improve readability. Each of these individual operator manuals covers a specific topic: Hardware components (system, coils, etc.) Software (measurement, evaluation, etc.) Another element of the complete operator manual is the information provided for the system owner of the MR system. The extent of the respective operator manual depends on the system configuration used and may vary. All components of the complete operator manual may include safety information that needs to be adhered to. The operator manuals for hardware and software address the authorized user. Basic knowledge in operating PCs and software is a prerequisite. 1.2 The current operator manual This manual may include descriptions covering standard as well as optional hardware and software. Contact your Siemens Sales Organization with respect to the hardware and software available for your system. The description of an option does not infer a legal requirement to provide it. syngo MR E11 11

12 1 Introduction The graphics, figures, and medical images used in this operator manual are examples only. The actual display and design of these may be slightly different on your system. Male and female patients are referred to as the patient for the sake of simplicity. 1.3 Intended use Your MAGNETOM MR system is indicated for use as a magnetic resonance diagnostic device (MRDD) that produces transverse, sagittal, coronal and oblique cross sectional images, spectroscopic images and/or spectra, and that displays the internal structure and/or function of the head, body, or extremities. Other physical parameters derived from the images and/or spectra may also be produced. Depending on the region of interest, contrast agents may be used. These images and/or spectra and the physical parameters derived from the images and/or spectra when interpreted by a trained physician yield information that may assist in diagnosis. Your MAGNETOM MR system may also be used for imaging during interventional procedures when performed with MR compatible devices such as in-room displays and MR Safe biopsy needles. The MAGNETOM MR system is not a device with measuring function as defined in the Medical Device Directive (MDD). Quantitative measured values obtained are for informational purposes and cannot be used as the only basis for diagnosis. For the USA only: Federal law restricts this device to sale, distribution and use by or on the order of a physician. Your MR system is a medical device for human use only! 12 Ortho Operator Manual

13 Introduction Authorized operating personnel The MAGNETOM MR system must be operated according to the intended use and only by qualified persons with the necessary knowledge in accordance with country-specific regulations, e.g. physicians, trained radiological technicians or technologists, subsequent to the necessary user training. This user training must include basics in MR technology as well as safe handling of MR systems. The user must be familiar with potential hazard and safety guidelines the same way the user is familiar with emergency and rescue scenarios. In addition, the user has to have read and understood the contents of the operator manual. Please contact Siemens Service for more information on available training options and suggested duration and frequency of such training Definitions of different persons Term used User/Operator/ Operating personnel System owner MR worker Explanation Person who operates the system or software, takes care of the patient or reads images Typically physicians, trained radiological technicians, or technologists Person who is responsible for the MR environment. This includes legal requirements, emergency plans, employee information and qualifications, as well as maintenance/repair. Person who works within the controlled access area or MR environment User/Operator as well as further personnel (for example, cleaning staff, facility manager, service personnel) syngo MR E11 13

14 1 Introduction Term used Siemens Service/service personnel Explanation Group of specially trained persons who are authorized by Siemens to perform certain maintenance activities References to Siemens Service include service personnel authorized by Siemens. 14 Ortho Operator Manual

15 Measurement 2 2 Measurement syngo MR E Overview of orthopedic imaging concept Large Joint Dot Engine Knee Dot Engine Hip Dot Engine Shoulder Dot Engine High-resolution fast 2D imaging syngo WARP: Imaging near orthopedic implants Isotropic 3D imaging Parametric mapping with syngo MapIt 58 15

16 2 Measurement 2.1 Overview of orthopedic imaging concept Orthopedic imaging is a comprehensive clinical applications package focusing on the following areas High throughput high-resolution imaging High-resolution fast 2D imaging: To deliver extremely high in-plane 2D resolution within clinically acceptable examination times. ( Page 37 High-resolution fast 2D imaging) Isotropic 3D imaging: To deliver enhanced workflow and increased diagnostic quality. ( Page 49 Isotropic 3D imaging) Advanced imaging techniques For helping in early diagnosis of osteoarthritis or monitoring of cartilage repair therapy. Parametric mapping (syngo MapIt): For improved diagnostic capabilities and therapy planning. ( Page 58 Parametric mapping with syngo MapIt) Dedicated orthopedic phased array coils The advances in resolution, image quality, workflow, scan speed and new imaging fields (biochemical) are only possible due to the dedicated orthopedic phased Array coils and the flexible coils. Siemens coils: Flex Large 4 (knee, shoulder, hip, ankle, pediatric MSK imaging) Flex Small 4 (wrist, elbow, pediatric MSK imaging) Body 18 (hip) Hand/Wrist 16 (hand, wrist) Foot/Ankle 16 (foot, ankle) Shoulder Large 16 (large shoulders) Shoulder Small 16 (small shoulders) CP Extremity Coil (not capable of parallel imaging) 16 Ortho Operator Manual

17 Measurement 2 QED coil: Tx/Rx 15-Channel Knee Coil 2.2 Large Joint Dot Engine The Large Joint Dot Engine provides a consistent workflow for all large joints. It consists of three Dot Engines: Knee Dot Engine ( Page 17 Knee Dot Engine) Hip Dot Engine ( Page 25 Hip Dot Engine) Shoulder Dot Engine ( Page 31 Shoulder Dot Engine) 2.3 Knee Dot Engine The Knee Dot Engine is intended to simplify and speed up the examination workflow. It provides guidance and easy adaption of the examination strategy. For 3D measurements the creation of MPRs is integrated into the workflow and supported by a guidance step for MPR planning. ( Page 21 3D examinations with integrated MPR planning) The Dot Engine user interfaces shown in this operator manual are examples only. The actual guidance texts and the design may be slightly different on your system. Planning the examination and measuring the localizer Patient has been registered Knee Dot Engine has been selected Adapting the examination to the patient After registration, the Patient View opens automatically. The default examination parameters are loaded. syngo MR E11 17

18 2 Measurement Selecting the examination strategy From the list: Select a suitable Exam Strategy for the patient. standard Speed focus Motion-insensitive (BLADE) High Bandwidth (WARP) For standard procedures. Provides fast protocols for when the patient cannot stay in the scanner for a longer period of time. For uncooperative/moving patients. Provides motion-insensitive protocols. Provides protocols with reduced sensitivity to susceptibility artifacts if the patient has MR Conditional implants. Please adhere to all safety instructions regarding implants. (Refer to Operator Manual MR System.) The pending protocols of the measurement queue are updated upon your selection. Starting the measurement of the scout The AAscout is used to determine anatomical structures. To start the Knee Dot Engine workflow, confirm the settings in the Patient View. 18 Ortho Operator Manual

19 Measurement 2 Results: The AutoAlign Scout is automatically measured and displayed. The localizer is the basis for the AutoAlign functionality, which provides consistent slice positioning of knee protocols without user interaction. (For a detailed description of the AutoAlign feature, please refer to: Operator Manual System and data management.) The next protocol opens. Changing the examination strategy subsequently Accessing the Patient View You can access the Patient View at any time during the examination. 1 To open the view, click the icon. 2 To confirm the settings and close the view, click the icon. Modifying parameters of measured protocols Changes in the Patient View only apply to pending protocols in the measurement queue. 1 To change the status of a protocol from measured to pending, select the measured protocol. 2 Select Rerun from here from the context menu (right-click with the mouse). 3 Open the Patient View. or Select Rerun from here with from the context menu (right-click with the mouse) The Patient View opens automatically. 4 Enter the requested modifications. syngo MR E11 19

20 2 Measurement Adjusting the slices and performing the measurements Localizers are displayed In the GSP segments, the slices for the following protocol are positioned by AutoAlign Knee. (For a detailed description of the AutoAlign feature, please refer to: Operator Manual System and data management.) Sample images with typical slice positioning are displayed in the Guidance View. Example: Guidance View for coronal slice positioning. 1 Check the slice positions for all subsequent measurements and adjust them, if necessary. You can also modify several sequence parameters of the current protocol using the Parameter View. Here you find the most important sequence parameters, e.g. the number of slices. To display the complete sequence parameters of the Routine parameter card, click the icon. 2 Start the measurement. The measurement is performed. The next protocol opens. 20 Ortho Operator Manual

21 Measurement 2 3 Repeat the above steps for all subsequent measurements D examinations with integrated MPR planning The 3D Knee Dot Engine provides an integrated planning step for MPR post-processing. MPRs of one or multiple 3D measurements are calculated immediately after each measurement. The MPR planning opens after the 3D measurements have been started. You are able to plan multiple MPR views with different orientations while the 3D measurements are running. During registration, the 3D Knee Dot Engine was selected 3D measurement has been started and the MPR planning step has opened Example: Guidance View for sagittal MPR view. 1 Select the desired MPR view from the list on the left side of the Guidance View. The corresponding MPR slice positions and orientations are displayed in the GSP segments. 2 Adapt the slice positioning, if necessary. In the Parameter View: You can also modify the view parameters alpha-numerically, e.g. the FoV. syngo MR E11 21

22 2 Measurement 3 Repeat the above steps for all MPR views. 4 Save the MPR settings. As soon as the 3D measurements have been concluded, the reconstruction of the MPRs is started automatically. For each 3D measurement, the defined MPR views are generated. The names of the resulting image series are a combination of the protocol name and the MPR view. For example: First 3D measurement: T1_SPC_FS Planned MPR views: transversal coronal sagittal Reconstructed MPR image series: T1_SPC_FS_MPR_tra T1_SPC_FS_MPR_cor T1_SPC_FS_MPR_sag If you repeat a 3D measurement, a new set of MPRs is calculated. You may use the resulting MPR views for the slice planning of subsequent measurements Configuring MPR views (optional) Dot Engine Step: The Dot Engine Step defines which strategies, decisions and global parameters are valid for the complete Dot Engine workflow examination. (For a detailed description, please refer to: Operator Manual Dot Cockpit.) Dot add-ins are predefined add-ins for Dot Engine Steps and program steps. Depending on the selected Dot add-in, you can configure different parameters of the Dot Engine Step. 22 Ortho Operator Manual

23 Measurement 2 Knee Dot add-ins: Generic Views MPR Assignment MPR Planning Assigning 3D measurements to the integrated MPR postprocessing Using the MPR Assignment Dot add-in you can define, for which 3D protocols the MPR post-processing is performed. 1 In the Dot Cockpit - Explorer: Select a 3D protocol. 2 Select Edit to open the protocol in the Program Editor. 3 Open the Step Properties dialog window by double-clicking the protocol. 4 Select AddIn Configuration. 5 Select MPR Assignment and activate the desired checkboxes. Adding MPR views Using the MPR Planning add-in, you can add new MPR views. 1 In the Queue: Select the MPR planning program step. 2 Open the Step Properties dialog window by double-clicking. syngo MR E11 23

24 2 Measurement 3 Select AddIn Configuration. 4 Select MPR Planning. 5 Add the MPR view by clicking Add MPR range. A new default MPR view is added to the list of available views. Renaming views 1 Right-click the added view with the mouse. 2 From the context menu: Select Rename. 24 Ortho Operator Manual

25 Measurement 2 3 Enter the new name. 4 Set the Guidance and Parameter Views. (Refer to Operator Manual Dot Cockpit.) Removing views 1 Right-click the view with the mouse. 2 From the context menu: Select Remove. 2.4 Hip Dot Engine The Hip Dot Engine is intended to simplify and speed up the examination workflow. It provides guidance and easy adaption of the examination strategy. The Hip Dot Engine offers three workflows: Two standard conventional 2D-workflows (unilateral and bilateral) and One bilateral 3D-workflow For 3D measurements the creation of MPRs is integrated into the workflow and supported by a guidance step for MPR planning. ( Page 29 Bilateral 3D hip examinations with integrated MPR planning) The Dot Engine user interfaces shown in this operator manual are examples only. The actual guidance texts and the design may be slightly different on your system. Planning the examination and measuring the localizer Patient has been registered Hip Dot Engine has been selected Adapting the examination to the patient After registration, the Patient View opens automatically. The default examination parameters are loaded. syngo MR E11 25

26 2 Measurement Selecting the examination strategy From the list: Select a suitable Exam Strategy for the patient. standard Speed focus High Bandwidth (WARP) For standard procedures. Provides fast protocols for when the patient cannot stay in the scanner for a longer period of time. Provides protocols with reduced sensitivity to susceptibility artifacts if the patient has MR Conditional implants. Please adhere to all safety instructions regarding implants. (Refer to Operator Manual MR System.) The pending protocols of the measurement queue are updated upon your selection. Starting the measurement of the scout The AAHip_Scout is used to determine anatomical structures. To start the Hip Dot Engine workflow, confirm the settings in the Patient View. 26 Ortho Operator Manual

27 Measurement 2 Results: The AutoAlign Scout is automatically measured and displayed. The localizer is the basis for the AutoAlign functionality, which provides consistent slice positioning of hip protocols without user interaction. (For a detailed description of the AutoAlign feature, please refer to: Operator Manual System and data management.) The next protocol opens. Changing the examination strategy subsequently Accessing the Patient View You can access the Patient View at any time during the examination. 1 To open the view, click the icon. 2 To confirm the settings and close the view, click the icon. Modifying parameters of measured protocols Changes in the Patient View only apply to pending protocols in the measurement queue. 1 To change the status of a protocol from measured to pending, select the measured protocol. 2 Select Rerun from here from the context menu (right-click with the mouse). 3 Open the Patient View. or Select Rerun from here with from the context menu (right-click with the mouse) The Patient View opens automatically. 4 Enter the requested modifications. syngo MR E11 27

28 2 Measurement Adjusting the slices and performing the measurements Localizers are displayed In the GSP segments, the slices for the following protocol are positioned by AutoAlign Hip. Sample images with typical slice positioning are displayed in the Guidance View. Example: Guidance View for coronal slice positioning. 1 Check the slice positions for all subsequent measurements and adjust them, if necessary. 2 To modify several sequence parameters of the current protocol, open the Parameters View. 28 Ortho Operator Manual

29 Measurement 2 Here you find the most important sequence parameters, e.g., the number of slices. To display the complete sequence parameters of the Routine parameter card, click the icon. 3 Start the measurement. The measurement is performed. The next protocol opens. 4 Repeat the above steps for all subsequent measurements Bilateral 3D hip examinations with integrated MPR planning The 3D workflows of the Hip Dot Engine provide an integrated planning step for MPR post-processing. MPRs of one or multiple 3D measurements are calculated immediately after each measurement. The MPR planning opens after the 3D measurements have been started. You are able to plan multiple MPR views with different orientations while the 3D measurements are running. For a detailed description of configuring MPR views, please refer to: ( Page 22 Configuring MPR views (optional)). syngo MR E11 29

30 2 Measurement During registration, a 3D workflow was selected 3D measurement has been started and the MPR planning step has opened Example: Parameters View for sagittal left MPR planning. 1 Select the desired MPR view from the list on the left side of the Parameters View. The corresponding MPR slice positions and orientations are displayed in the GSP segments. 2 Adapt the slice positioning, if necessary. In the Parameters View: You can also modify the view parameters alpha-numerically, e.g. the FoV. 3 Repeat the above steps for all MPR views. 4 Save the MPR settings. As soon as the 3D measurements have been concluded, the reconstruction of the MPRs is started automatically. For each 3D measurement, the defined MPR views are generated. 30 Ortho Operator Manual

31 Measurement 2 The names of the resulting image series are a combination of the protocol name and the MPR view. For example: First 3D measurement: PD_SPC_FS Planned MPR views: transversal coronal sagittal Reconstructed MPR image series: PD_SPC_FS_MPR_tra PD_SPC_FS_MPR_cor PD_SPC_FS_MPR_sag If you repeat a 3D measurement, a new set of MPRs is calculated. You may use the resulting MPR views for the slice planning of subsequent measurements. 2.5 Shoulder Dot Engine The Shoulder Dot Engine is intended to simplify and speed up the examination workflow. It provides guidance and easy adaption of the examination strategy. The Shoulder Dot Engine offers two workflows: Standard conventional 2D-workflow and 3D-workflow For 3D measurements the creation of MPRs is integrated into the workflow and supported by a guidance step for MPR planning. ( Page 35 3D shoulder examinations with integrated MPR planning) syngo MR E11 31

32 2 Measurement The Dot Engine user interfaces shown in this operator manual are examples only. The actual guidance texts and the design may be slightly different on your system Planning the examination and measuring the localizer Patient has been registered Shoulder Dot Engine has been selected Adapting the examination to the patient After registration, the Patient View opens automatically. The default examination parameters are loaded. Selecting the examination strategy From the list: Select a suitable Exam Strategy for the patient. standard Speed focus Motion-insensitive (BLADE) For standard procedures. Provides fast protocols for when the patient cannot stay in the scanner for a longer period of time. For uncooperative/moving patients. Provides motion-insensitive protocols. 32 Ortho Operator Manual

33 Measurement 2 Please adhere to all safety instructions regarding implants. (Refer to Operator Manual MR System.) The pending protocols of the measurement queue are updated upon your selection. Starting the measurement of the scout The AAShoulder_Scout is used to determine anatomical structures. To start the Shoulder Dot Engine workflow, confirm the settings in the Patient View. Results: The AutoAlign Scout is automatically measured and displayed. The localizer is the basis for the AutoAlign functionality, which provides consistent slice positioning of shoulder protocols without user interaction. (For a detailed description of the AutoAlign feature, please refer to: Operator Manual System and data management.) The next protocol opens. Changing the examination strategy subsequently Accessing the Patient View You can access the Patient View at any time during the examination. 1 To open the view, click the icon. 2 To confirm the settings and close the view, click the icon. Modifying parameters of measured protocols Changes in the Patient View only apply to pending protocols in the measurement queue. 1 To change the status of a protocol from measured to pending, select the measured protocol. 2 Select Rerun from here from the context menu (right-click with the mouse). syngo MR E11 33

34 2 Measurement 3 Open the Patient View. or Select Rerun from here with from the context menu (right-click with the mouse) The Patient View opens automatically. 4 Enter the requested modifications Adjusting the slices and performing the measurements Localizers are displayed In the GSP segments, the slices for the following protocol are positioned by AutoAlign Shoulder. Sample images with typical slice positioning are displayed in the Guidance View. Example: Guidance View for transversal slice positioning. 1 Check the slice positions for all subsequent measurements and adjust them, if necessary. 2 To modify several sequence parameters of the current protocol, open the Parameters View. 34 Ortho Operator Manual

35 Measurement 2 Here you find the most important sequence parameters, e.g., the number of slices. To display the complete sequence parameters of the Routine parameter card, click the icon. 3 Start the measurement. The measurement is performed. The next protocol opens. 4 Repeat the above steps for all subsequent measurements D shoulder examinations with integrated MPR planning The 3D workflow of the Shoulder Dot Engine provides an integrated planning step for MPR post-processing. MPRs of one or multiple 3D measurements are calculated immediately after each measurement. The MPR planning opens after the 3D measurements have been started. You are able to plan multiple MPR views with different orientations while the 3D measurements are running. For a detailed description of configuring MPR views, please refer to: ( Page 22 Configuring MPR views (optional)). syngo MR E11 35

36 2 Measurement During registration, the 3D workflow was selected 3D measurement has been started and the MPR planning step has opened Example: Parameters View for sagittal MPR planning 1 Select the desired MPR view from the list on the left side of the Parameters View. The corresponding MPR slice positions and orientations are displayed in the GSP segments. 2 Adapt the slice positioning, if necessary. In the Parameters View: You can also modify the view parameters alpha-numerically, e.g. the FoV. 3 Repeat the above steps for all MPR views. 4 Save the MPR settings. As soon as the 3D measurements have been concluded, the reconstruction of the MPRs is started automatically. For each 3D measurement, the defined MPR views are generated. 36 Ortho Operator Manual

37 Measurement 2 The names of the resulting image series are a combination of the protocol name and the MPR view. For example: First 3D measurement: PD_SPC_FS Planned MPR views: transversal coronal sagittal Reconstructed MPR image series: PD_SPC_FS_MPR_tra PD_SPC_FS_MPR_cor PD_SPC_FS_MPR_sag If you repeat a 3D measurement, a new set of MPRs is calculated. You may use the resulting MPR views for the slice planning of subsequent measurements. 2.6 High-resolution fast 2D imaging Imaging of the musculoskeletal (MSK) system requires high resolution with the necessary contrast for precise detection of small and complex structures Optimization with TSE sequence The flexible TSE sequence is optimized for a maximum matrix size and small FoV. This TSE sequence, together with parallel imaging techniques, delivers extremely high in-plane 2D resolution within clinically acceptable examination times, allowing for a more accurate diagnosis. syngo MR E11 37

38 2 Measurement Alternative protocols with faster scan times are also available in the Siemens protocol tree. The concept of high-resolution fast imaging utilizing the TSE sequence. The high-resolution fat-suppressed PD-weighted TSE image is a tool helping in accurate diagnosis. Advantages By using new reordering techniques, the TSE sequence allows for: a more flexible choice of TE for better optimization of contrast a more flexible choice of echo train lengths to maintain image contrast while optimizing protocols a flexible choice of fat suppression techniques (WEAK, STRONG, SPAIR, STIR) Optimizing echo time PD-weighted contrast is the gold standard in differentiating cartilage defects. Contrast is optimized by varying the echo time (the preferred TE varies from physician to physician). 38 Ortho Operator Manual

39 Measurement 2 (1) TE 20 ms (2) TE 40 ms Optimizing echo train length (ETL) Increasing the ETL will reduce the scan time while the contrast is mostly maintained. The flexible reordering scheme allows greater flexibility (even and odd ETL, reduced blurring). (1) TE 24 ms; ETL 5; 4 min (2) TE 24 ms; ETL 7; 3 min (3) TE 24 ms; ETL 10; 2 min (4) TE 24 ms; ETL 15; 1:20 min syngo MR E11 39

40 2 Measurement Optimizing fat saturation Fat saturation is useful when imaging suspected bone trauma or edema. It allows good differentiation of surface cartilage lesions. FatSat: Uses a spectrally selective pulse to saturate the fat spins before the imaging sequence. Has 2 settings: (a) STRONG which delivers a darker fat than (b) WEAK. SPAIR: Uses an adiabatic spectrally selective pulse which is insensitive to dielectric effects. Useful at 3 Tesla in the hip. STIR: Uses a spatial inversion pulse with a short inversion time to null fat. Only recommended where fat suppression is difficult due to B0 issues, i.e., with MR Conditional implants. Example: A cartilage tear can sometimes be better visualized using FatSat techniques (right) as shown above. Optimizing fat suppression For MSK imaging the fat suppression can be optimized for TSE, SE and SPACE sequences. The main advantages are: increased saturation homogeneity increased saturation strength decreased sensitivity to B0 inhomogeneities 40 Ortho Operator Manual

41 Measurement 2 The optimized fat suppression region Joints for MSK imaging can be selected in the Fat Suppression Optimization dialog window. To open the dialog window, click the button on the right side of the Fat suppr. dropdown menu. Prerequisite: Fat sat. is selected. Protocols for joints imaging are provided for 3 Tesla only. The optimized fat suppression should only be used for foot-ankle, knee, hand-wrist and elbow imaging. BLADE technique The BLADE technique is available for all MSK regions and can be configured for T1, T2, and PD contrasts. It is compatible with multichannel coils, and ipat can be employed. Any orientation can be used (sagittal, coronal and axial). BLADE is fully integrated in the TSE sequence. For a detailed description, please refer to: Application Brochure Pulse Sequences. syngo MR E11 41

42 2 Measurement Advantages of oversampling: Wrap-around artifacts (streaking) avoided Good results with respect to movement artifacts Increased SNR (1) Knee coronal: FoV , 0.4 mm 0.4 mm, TE = 47 ms (2) Wrist: FoV , 0.3 mm 0.3 mm, TE = 47 ms Reducing examination noise The quiet MR sequences increase patient comfort and enable MR examinations for noise-sensitive patients. The noise reduction mainly depends on the protocol settings. Compared to conventional imaging, a reduction of approximately 10 db(a) can be achieved. Quiet protocols are available in the Siemens protocol tree. The protocols for quiet MSK imaging include: localizer based on GRE sequence TSE sequence (proton density weighted with/without fat saturation) For a detailed description of the quiet MR sequences, please refer to Operator Manual Neuro. Reducing SAR for hip imaging In particular unilateral hip examinations are limited by SAR. For this reason, B1 shimming provides an option to reduce the SAR level of a protocol by optimizing the transmit parameters of the ptx channels. 42 Ortho Operator Manual

43 Measurement 2 In addition, protocols with reduced SAR are provided for unilateral hip imaging. Select Low SAR patient specific from the B1 Shim mode list in the System ptx Volumes parameter card. The SAR reduction depends on the size and position of the FOV and requires an additional adjustment scan. 2.7 syngo WARP: Imaging near orthopedic implants MR imaging in the vicinity of metal implants is challenging, firstly because of safety concerns and secondly because of image distortions. In general, an MR examination is contraindicated for patients with electronic or electronically conductive implants or metals, especially those containing ferromagnetic foreign matter. Particularly with regard to magnetic forces and heating of implants and surrounding tissue, please adhere to all safety instructions. (Refer to Operator Manual MR System.) The main source of artifacts seen when imaging patients with MR Conditional implants is related to distortions of the local magnetic field caused by the large difference in magnetic susceptibility between metal and tissue. The degree of field distortions depends on the shape, the location and the material properties of the metal implant. syngo WARP provides dedicated imaging techniques based on the TSE sequence in order to reduce susceptibility-related artifacts: syngo MR E11 43

44 2 Measurement high bandwidth optimizations to reduce the level of artifacts, for example geometric distortions and contrast changes are minimized VAT (View Angle Tilting) technique to correct for in-plane distortions (geometric distortion of the frequency encoding, for example image pixels are displaced along the frequency-encoding direction) SEMAC (Slice Encoding for Metal Artifact Correction) technique to correct for through-plane distortions (geometric distortions of the excited slice profile, for example the excited slices are curved instead of being plane) VAT and SEMAC are available if the WARP checkbox is activated in the Sequence Part 2 parameter card WARP: high bandwidth By activating the WARP checkbox, the bandwidth of the RF pulses will be increased. In combination with a high readout bandwidth selected, the TSE sequence becomes less sensitive to field distortions. High readout bandwidth: 44 Ortho Operator Manual

45 Measurement 2 reduces in-plane distortions avoids image blurring when using the VAT technique reduces the SNR of the image High RF pulse bandwidth (combined with small slice thickness): reduces through-plane distortions depends on the RF pulse type: Fast has a higher bandwidth, but also a higher SAR increases the specific absorption rate (SAR) Practical hints for imaging near MR Conditional implants with the TSE sequence: always select the WARP checkbox select a high readout bandwidth, for most cases Hz/ pixel is an advisable value select RF pulse type Fast unless the SAR gets too high SAR can be reduced by selecting a lower refocusing flip angle replace conventional fat suppression by STIR imaging (Short Tau Inversion Recovery): select magnetic preparation Slice-sel. IR with TI approx. 160ms (1.5T) or 200ms (3T) If WARP is selected, a W is added to the sequence string displayed in the image (only if VAT and SEMAC are not selected). syngo MR E11 45

46 2 Measurement (1) without syngo WARP (2) with syngo WARP WARP: View Angle Tilting (VAT) technique VAT compensates in-plane distortions by adding an additional readout gradient in the slice direction. The corresponding value in the Sequence Part 2 parameter card specifies the amplitude of the view angle tilting gradient: 0%: VAT is deactivated (no distortion correction) 100%: VAT has the same amplitude as the slice-selective gradient (full readout distortion correction) Performing the measurement with VAT may cause blurring of the image. Blurring can be reduced by: using thin slices using a high readout bandwidth The result of VAT strongly depends on the type and orientation of the implant, as well as other imaging parameters. In general, VAT can only reduce in-plane distortions. If VAT does not improve the image quality, this means that other effects are dominating, for example through-plane distortions. In that case, try to use thinner slices, RF pulse type Fast or SEMAC. 46 Ortho Operator Manual

47 Measurement 2 If VAT is selected, a V is added to the sequence string displayed in the image (only if SEMAC is not selected). (1) without VAT (2) with VAT WARP: Slice encoding for metal artifact correction (SEMAC) SEMAC provides a through-plane distortion correction by performing additional phase encoding in the slice direction. SEMAC is most effective for severe field distortions, for example near large metal structures such as full joint replacement of the hip or knee. SEMAC can only be applied in combination with: VAT set to 100% slice distance of 0% A SEMAC value of 0 means that no SEMAC is applied. syngo MR E11 47

48 2 Measurement The measurement time will be prolonged by the number of SEMAC steps. Since SEMAC increases the SNR, try to reduce the scan time by reducing averages, apply parallel imaging or partial fourier. The required number of SEMAC phase-encoding steps depends on the size, shape and material of the implant and may vary from patient to patient. For joint arthroplasty 8-12 SEMAC steps is usually a reasonable value. Metals causing stronger artifacts, such as stainless steel or cobalt chromium alloys, require higher SEMAC steps, whereas titanium implants usually require lower values or even no SEMAC at all. SEMAC cannot be used in combination with 3D TSE, BLADE, TimCT, multiple slice groups, and DIXON. If SEMAC is selected, a S is added to the sequence string displayed in the image text. (1) without SEMAC (2) with SEMAC 48 Ortho Operator Manual

49 Measurement Isotropic 3D imaging High-resolution fast isotropic 3D imaging is becoming increasingly more important as a means of enhancing workflow and providing more accurate diagnosis. Isotropic 3D imaging allows for fully flexible examination, i.e. depending on the suspected diagnosis, images can be reformatted in any plane. Isotropic sequences: Using an isotropic 3D sequence, the images can be reformatted with high in-plane and through-plane resolution. Utilization of such a sequence introduces further improvements in the workflow by acquiring one 3D series that can be reformatted in the different planes needed for precise diagnosis. Siemens provides five different sequences with specified contrasts: 3D SPACE ( Page 49 3D SPACE) 3D TrueFISP ( Page 50 3D TrueFISP) 3D DESS (Dual Echo Steady State) ( Page 51 3D DESS) 3D MEDIC ( Page 53 MEDIC) 3D FISP For a detailed description of the sequences, please refer to: Application Brochure Pulse Sequences D SPACE Concept: Different planes can be reconstructed from the isotropic data set for high-resolution diagnosis of cartilage, ligaments, and meniscus in the knee joint. syngo MR E11 49

50 2 Measurement (1) PD-weighted SPACE, isotropic resolution 0.5 mm (2) PD-weighted SPACE with FatSat, isotropic resolution 0.5 mm D TrueFISP The TrueFISP sequence is used for balanced steady state imaging. On each of the gradient axes the net gradient moment is zero. It has a good SNR, but is prone to banding artifacts in regions of compromised homogeneity, i.e., MR Conditional implants. (1) RF (2) Slice selection 50 Ortho Operator Manual

51 Measurement 2 (3) Phase encoding (4) Frequency encoding (5) Signal (SS-FID/SS-echo) Minimize TR by selecting a high readout bandwidth to avoid interference streaks in the image. Ankle, isotropic resolution 0.3 mm, reformatted below in sagittal, coronal, and axial direction D DESS In the steady state, two signals are produced an FID signal and an echo. With DESS (Dual Echo Steady State) these two signals are measured and combined to produce a single image. syngo MR E11 51

52 2 Measurement (1) RF (2) Slice selection (3) Phase encoding (4) Frequency encoding (5) Signal (SS-FID/SS-echo) Use primarily in orthopedic imaging with good contrast between synovial fluid and cartilage. A non-selective excitation pulse is activated beforehand for fat suppression at a short TR. 52 Ortho Operator Manual

53 Measurement 2 (1) Shoulder, isotropic resolution 0.7 mm (2) Knee, isotropic resolution 0.6 mm MEDIC The MEDIC sequence is a multi-echo GRE sequence where up to 6 echoes are combined to produce a single image. (1) RF (2) Slice selection (3) Phase encoding syngo MR E11 53

54 2 Measurement (4) Frequency encoding (5) Signal (dashed line: T2* decay) Gives very good contrast for meniscus evaluation. (1) Shoulder coronal (2) Knee sagittal Image examples Example: 10 minute knee exam 54 Ortho Operator Manual

55 Measurement 2 Isotropic data set 0.5 mm. syngo MR E11 55

56 2 Measurement Reformat along x diagnosis-based planes: (1) Meniscus reformat (2) ACL reformat (3) Coronal reformat (4) Patella reformat Example: Precise localization of anatomy (meniscus) 56 Ortho Operator Manual

57 Measurement 2 Example: Complex geometry simple reformatting (radial reformats for hip imaging) syngo MR E11 57

58 2 Measurement 2.9 Parametric mapping with syngo MapIt Parametric mapping with syngo MapIt may improve both the accuracy of diagnosis and planning and also may monitor the effectiveness of therapy. At present, the main focus is on: T2 and T2* mapping, T1 mapping 58 Ortho Operator Manual

59 Measurement T2 or R2 mapping with syngo MapIt Clinical use to aid in: Cartilage repair therapies (microfracture therapy vs MACT therapy). (MACT = Matrix-associated Autologous Chondrocyte Transplantation). Cartilage repair therapies (MACT therapy follow up) Early OA detection (femoral acetabular impingement). (OA = Osteoarthritis). T2 provides information on structural changes in the collagen within the cartilage. T2 depends on the orientation as a function of the magic angle effect. T2 provides information on changes in the water content of the cartilage. Compressed areas show less water content lower T2. Less compressed areas show greater water content higher T2. T2 has been used to study cartilage repair therapies and to provide information on cartilage softening. T2 is measured using a multi-echo spin echo with up to 32 echoes. Each echo produces an image. The map is produced by a pixel-bypixel analysis. Instead of T2, R2 = 1/T2 can optionally be calculated T2 or R2 mapping: protocol parameters For T2 or R2 mapping use the se_mc sequence. Use the Inline MapIt parameter card. syngo MR E11 59

60 2 Measurement MapIt Select T2 or R2 to turn on the Inline technology. Measurements Are set to 1. Contrasts TE TR Noise threshold Save original images Up to 32 echoes possible. More echoes provide a better fit. Set the echo time for each echo. Keep maximum TE to less than or similar to expected T2 values. Use TR values > 1000 ms. Echoes with signals less than this value will be ignored in the fit. If in doubt, leave at default value. Keeps the morphological base images in the database Examples in cartilage repair therapies (microfracture therapy vs MACT therapy) MFX therapy creates microfractures in the bone. Cartilage regeneration is promoted by the released blood and marrow. 60 Ortho Operator Manual

61 Measurement 2 These are the characteristics of this method: Reduced T2 in the region of MFX therapy. Matrix-associated autologous chondrocyte transplantation (MACT). An operative procedure using a cell seeded collagen matrix. Used for the treatment of localized full thickness cartilage defects. Courtesy of S. Trattnig, Dept. Radiology, University Vienna T2* or R2* mapping with syngo MapIt T2* is the apparent transverse relaxation rate and has a T2 component. It can be used as a substitute for T2 mapping. Instead of T2*, R2* = 1/T2* can be optionally calculated. syngo MR E11 61

62 2 Measurement T2* also has a component which depends on the field change within the voxel, resulting from: Macroscopic field changes, i.e. main field homogeneity, large susceptibility fields from implants. Macroscopic field changes due to susceptibility variations, i.e. bone-cartilage interface. Microscopic field changes from the microstructure within the voxel. T2* is measured using a multi-echo gradient-echo sequence. Each TE gives an image. A pixel-by-pixel analysis produces the T2* map. (1) RF (2) Slice selection (3) Phase encoding (4) Frequency encoding (5) Signal (dashed line: T2* decay) 62 Ortho Operator Manual

63 Measurement T2* or R2* mapping: protocol parameters For T2* or R2* mapping use the gre sequence. Use the Inline MapIt parameter card. MapIt Select T2* or R2* to turn on the Inline technology. Measurements Are set to 1. Contrasts TE Noise threshold Save original images Up to 12 echoes possible. Set the echo time for each echo. Keep maximum TE to less than or similar to expected T2 values. Echoes with signals less than this value will be ignored in the fit. If in doubt, leave at default value. Keeps the morphological base images in the database. In the Sequence Part 1 parameter card: syngo MR E11 63

64 2 Measurement Contrasts Bandwidth Flow comp. Readout mode Up to 12 echoes possible. Must be entered for each echo. Use the same bandwidth for all echoes. Useful in the abdomen Select mono or bi-polar Clinical use in cartilage repair therapies (microfracture therapy) MFX therapy creates microfractures in the bone. Cartilage regeneration is promoted by the released blood and marrow. T2* is reduced in the region of MFX therapy. A small patient study suggests that variability is better with T2*. 64 Ortho Operator Manual

65 Measurement Fast T1 mapping with syngo MapIt Clinical use to aid in: dgemric Pre-operative staging Prediction of therapy outcome Therapy follow up T1 mapping is used in cartilage to track proteoglycans. The gold standard was multiple IR spin echo measurements. However, the very long acquisition time of up to 30 minutes makes it clinically difficult. Fast T1 mapping with syngo uses a 2 angle VIBE measurement. The acquisition time is significantly reduced to 3 minutes. To calculate T1, this technique utilizes 2 spoiled GRE measurements, each identical except for different flip angles. syngo MapIt calculates T1 on a pixel-by-pixel basis. T1 mapping with B1 correction Variable flip angle techniques used by syngo MapIt are intrinsically sensitive to inhomogeneities of the transmit RF field (B1). syngo MapIt can perform B1 corrections to improve the spatial homogeneity and the reproducibility of the acquired T1 maps. syngo MR E11 65

66 2 Measurement To enable this feature, run the Siemens B1mapForT1mapping protocol prior to the T1 mapping protocol. The three-dimensional FoV of the B1mapForT1mapping protocol should be greater or equal to the FoV of the T1 mapping protocol. B1 corrections will be performed automatically. The image series with the corrected T1 maps is marked as T1_Images_B1corr instead of T1_Images. Please note: The resulting T1 map values may overestimate the absolute T1 values! This behavior is expected due to the technique used the variable flip angle method. Thus a relative comparison of T1 values within tissues should be made T1 mapping: protocol parameters For fast T1 mapping use the vibe sequence. Use the Inline MapIt parameter card. MapIt Auto angle calculation T1 estimate Select T1 map. Select, if required. Two optimum angles will be automatically calculated, based on the estimated T1. 66 Ortho Operator Manual

67 Measurement 2 Flip angle Alternatively, select two flip angles. syngo MR E11 67

68 2 Measurement 68 Ortho Operator Manual

69 Post-processing 3 3 Post-processing 3.1 Fusing biochemical maps and images 70 syngo MR E11 69

70 3 Post-processing 3.1 Fusing biochemical maps and images The following example describes how to overlay T2/T2* maps generated with syngo MapIt with their corresponding anatomical images. Subsequently, manual cartilage segmentation is performed. The same procedure applies when using T1 maps. In this case, two series containing the morphological base images for the two flip angles are stored together with the T1 map series Loading the data T2/T2* maps have been generated with syngo MapIt Anatomical base images are available (Save original images activated during mapping) Loading the maps 1 Select the mapping series in the Patient Browser. 2 Click the 3D MPR icon to start image processing as MPR. 3 Window the mapping images to optimize their contrast and brightness. Loading the original images The series preceding the T2/T2* maps contains the morphological base images for all echoes. 1 Select the morphological series in the Patient Browser. 2 Load the data to 3D Fusion with the icon. 3 In the 3D Series List, select the echo images you want to use. 70 Ortho Operator Manual

71 Post-processing 3 The Fusion Registration dialog window is displayed. Registration is not needed in this case. 4 Skip Fusion Registration with OK Optimizing the image display 1 Open the Fusion Definition MPR dialog window with Fusion > Fusion Definition. 2 In order to get access to the mask menu, click Advanced. 3 Hide the background noise in the mapping images by increasing the L value for Masking to 1 (left spin box). 4 Select suitable Color Lookup Tables for the map and the morphological images to optimize their view. Recommended settings: Rainbow for mapping images (left selection list), Gray Scale for morphological images (right selection list). 5 Set the T2/T2* baseline map Window Level to a default value by changing the left C and W values (e.g. 45 each). syngo MR E11 71

72 3 Post-processing Visualizing the cartilage It is easier to segment the cartilage if you work on the morphological images. 1 In the Fusion Definition MPR dialog window, move the Mixing Ratio slider to the right to display the morphological image only. 2 Activate VOI Punch Mode with the icon in the Settings subtask card. The VOI Punch Mode dialog window opens. VOI drawing is activated automatically. 3 Trace the cartilage in the morphological image. Double-click to finish. 4 Remove the non-cartilage part of the mapping image with the Keep Inside icon. 5 In order to provide for good fusion, set a Mixing Ratio of 50% in the Fusion Definition MPR dialog window. 72 Ortho Operator Manual

73 Post-processing Saving and filming the images 1 Select the respective segment for saving or filming. 2 Save the images as a new series with the icon. 3 To film the images selected, click the icon. syngo MR E11 73