Inveon Multimodality PET Overview

The Inveon Multimodality is configured with a PET insert, which is a module docked to the rear side of the scanner. The PET insert has four rings of detectors, each ring consisting of 16 detectors. PET acquisitions are acquired from the same position on the bed pallet as CT and SPECT acquisitions, making it possible to co-register images without changing geometry. It is important to note that the bed must be in bed position #3 to acquire PET data. This training describes how to setup PET acquisition, histogram, and reconstruction protocols. Once these protocols are created, you will learn how to setup a PET workflow. At the end of the training, you will learn how to create PET/CT workflow, which runs both PET and CT acquisitions in a seamless workflow solution.   Course Objectives   Identify the components of the PET GUI   List the steps to build a PET only Workflow   List the steps to build a PET/ CT Workflow   List the steps to create a PET Protocol Upon completion of this course you will be able to: You should now be able to: Identify the components of the PET GUI List the steps to creating a PET Protocol Acquisition Histogram Reconstruction List the steps to the PET Workflow Workflow Setup Running a PET Workflow List the steps to the PET/ CT Workflow Workflow Setup Running a PET/CT Workflow Continue to the course assessment to complete the course. In the MM-Motion panel of the Status Bar, the Rear Shield indicates whether the rear shield is open (100%) or closed (0%).  The rear shield must be open during a PET acquisition; this is automatically done when a PET workflow is started.  If you are manually moving the bed into the PET field of view, you must manually open the rear shield.  Though all PET isotopes emit 511 keV photons, it is important to select the correct isotope used so IAW can accurately account for the isotope’s half-life and branching fraction.  To configure additional PET isotopes, select Tools > Options and click PET > Isotope. Click Add to create additional isotopes along with their half-life and branching fraction, and click OK to save the settings. After protocols are configured, they are typically added to a workflow to be run, although histogram and reconstruction protocols can be run independently if you already have listmode data or a sinogram to reconstruct. In short, the acquisition generates listmode data, the histogram converts listmode data into a sinogram, and the reconstruction uses the sinogram to reconstruct images. To create a workflow, right-click the Workflows folder and click New Workflow. In the following order, a complete PET workflow includes an acquisition, a histogram, and a reconstruction.   Once you have created a new workflow, you can drag and drop protocols from the System Navigator to the Workflow panel. Optionally, you can click Add to select protocols for the workflow. Make certain to add the protocols in the correct order; i.e. acquisition before histogram or reconstruction.     PET Workflow setup PET Workflow setup Checklist TitleChecklist TypeChecklist ContentStep 1HTMLAfter you have opened a new workflow protocol, drag and drop the desired acquisition, histogram, and reconstruction protocols into the workflow. Step 2HTMLOptionally, you can click Add or Remove to edit the workflow. Note that the order cannot be changed once they're in the workflow. Step 3HTMLClick Save, and name the workflow. Protocols added to a workflow are run sequentially in the order they are placed in the workflow setup. PET acquisition data are saved in listmode (*.lst) files, PET histogrammed data are stored in sinograms (*.scn), and PET reconstructed images are *.img files. Carefully confirm the runtime parameters before starting the workflow. Run a Workflow Run a Workflow Checklist TitleChecklist TypeChecklist ContentStep 1HTMLMake certain microQ is running on the local host workstation prior to executing any PET histogram or reconstruction protocols.Step 2HTMLLaser align the object in the center of the laser crosshairs, and select the radiobutton for PET to center the object in the PET field of view for the PET workflow.Step 3HTMLType a name for the dataset in the Dataset Name field (example: DDMMYY_objectID_study) Step 4HTMLClick Setup. Step 5HTMLDefine the runtime parameters for each protocol. Refer to the User Manual for more details. Step 6HTMLClick Start Workflow. Step 7HTMLRefer to ASIPro and IRW User Manuals to view image data. Note that PET sinogram data can only be viewed in ASIPro, not IRW. The System Navigator panel in IAW allows you to easily organize protocols, datasets, and workflows.  PET protocols can be created in either User Folders or System Calibration, depending on the purpose of the protocols created. To create a new protocol: Right-click User Folders and click Add Study. Open the study folder, then open its Protocols subfolder. Right-click the folder that corresponds to the protocol you want to create (Acquisition, Histogram, or Reconstruction), click New Protocol, and choose the modality for the protocol you wish to create. The PET acquisition protocol allows you to configure two different types of acquisition modes: Emission or Cylinder Normalization.  PET acquisition can be acquired by a total number of counts, seconds, or both. More information on the acquisition parameters can be found in the User Manual. Click on the checklist below for steps to create a PET acquisition protocol.   Acquisition Protocol Setup Acquisition Protocol Setup Checklist TitleChecklist TypeChecklist ContentStep 1HTMLWithin a study folder, right-click Acquisitions > New Protocol > PET. Step 2HTMLSelect an Acquisition Mode from the drop-down menu. Step 3HTMLModify the PET acquisition parameters for your study. For detailed information on acquisition parameters, refer to the User Manual.Step 4HTMLOptionally, type a description of the scan in the Description field. Step 5HTMLClick Save to save the protocol, and then click Close. The PET histogram protocol determines how PET listmode data is histogrammed. The data is binned into a sinogram for each time frame and each gate bin. PET histogram parameters are described in further detail in the User Manual.   Histogram Protocol Setup Histogram Protocol Setup Checklist TitleChecklist TypeChecklist ContentStep 1HTMLWithin a study folder, right-click Histograms > New Protocol > PET. Step 2HTMLModify the PET histogram parameters for your study. For detailed information on histogram parameters, refer to the User Manual.Step 3HTMLOptionally, enable gating. Refer to the User Manual as well as BioVet® User Manual for more details. Note that PET gating is retrospective, where gated signals are received during PET acquisition and flagged accordingly in the list mode data. Step 4HTMLClick Save.Step 5HTMLOptionally, you can run the protocol immediately without first adding it to a workflow if you already have the input PET sinogram availabale. Click Submit, and select the Input Listmode File. A PET reconstruction protocol determines how PET sinogram files are to be reconstructed into images, including what algorithms to use, and what corrections apply to the reconstruction. PET reconstruction parameters are described in further detail in the User Manual. Reconstruction Protocol Setup Reconstruction Protocol Setup Checklist TitleChecklist TypeChecklist ContentStep 1HTMLWithin a study folder, right-click Reconstructions  > New Protocol > PET Step 2HTMLSelect a reconstruction algorithm from the drop down menu and modify the reconstruction parameters as desired. Refer to the User Manual for detailed descriptions of the protocol parametersStep 3HTMLClick Save. Step 4HTMLOptionally, if you want to run the protocol immediately, click Submit and select the Sinogram Input File, Normalization Input File, and optional Attenuation Input File. The Inveon Multimodality offers the flexibility of performing sequential PET and CT scans in order to create an anatomical and functional image pair, or to generate attenuation-corrected PET data. A PET/CT workflow combines any number of CT and PET acquisitions, histograms, and reconstructions in a seamless workflow; the specimen remains in the same position on the same bed pallet using the co-scan length of the bed pallet. It is important to note that specimens must be positioned correctly on the bed pallet when performing PET/CT scans. In order to achieve maximum co-scan length (12.7 cm) for a PET/CT workflow, the starting bed position must be at or near its home position. Refer to the User Manual for more information on preparing the bed pallet for co-scans as well as loading specimens for PET/CT scans. Once you have created a new workflow, you can drag and drop protocols from the System Navigator to the Workflow panel. Optionally, you can click Add to select protocols for the workflow. Make certain to add the protocols in the correct order; i.e. acquisition before histogram or reconstruction. PET/CT Workflow Setup PET/CT Workflow Setup Checklist TitleChecklist TypeChecklist ContentStep 1HTMLAfter you have opened a new workflow protocol, drag and drop the desired acquisition and reconstruction protocols into the workflow. Step 2HTMLOptionally, you can click Add or Remove to edit the workflow. Note that the order cannot be changed once they're in the workflow. Step 3HTMLClick Save, and name the workflow. Protocols added to a workflow are run sequentially in the order they are placed in the workflow setup.  CT acquisition data are saved as *.cat files, PET acquisition data are saved in listmode (*.lst) files, PET histogrammed data are stored in sinograms (*.scn) files, and PET and CT reconstructed images are *.img files.  Before you begin your workflow, make certain you have run the CT Tube Conditioning and that the center offset calibration in your CT acquisition protocol is up-to-date.  Carefully check the Runtime Parameters before starting the workflow. View the checklist and video below to learn how to run a PET/CT workflow   Running a PET/CT Workflow Running a PET/CT Workflow Checklist TitleChecklist TypeChecklist ContentStep 1HTMLMake certain microQ is running on the host computer prior to any PET histogram or reconstruction.Step 2HTMLConfirm that COBRA is online. Step 3HTMLLaser align the object in the center of the laser crosshairs, and select the radiobutton for CT and check the box “PET Included".  Shuttle the bed to position 3 and click OK.Step 4HTMLType a name for the dataset in the Dataset Name field (example: DDMMYY_objectID_study). Step 5HTMLClick Setup. Step 6HTMLDefine the runtime parameters for each protocol. Refer to the User Manual for more details. Step 7HTMLInput a PET/CT transformation matrix file that will be used to register the PET and CT images. Ignore this step if using this workflow to generate a new transformation matrix. Step 8HTMLClick Start Workflow. Step 9HTMLRefer to ASIPro and IRW User Manuals to view image data. Note that PET sinogram data can only be viewed in ASIPro, not IRW. Video: How to Setup a Workflow Video: How to Setup a Workflow