Mammography Integration Profiles: Acquisition Workflow & Image Content

1. Mammography Integration Profiles:Acquisition Workflow & Image Content Christoph Dickmann Siemens Healthcare IHE NA Connectathon Webinar 2008

2. FFDM - not just another modality Full Field Digital Mammography (FFDM) imaging has specific requirements: • High patient throughput (e.g. 300 patients/day) • “On-line” work-up, screening/ diagnostic • Common use of CAD (Computer Aided Detection) • Double reading • Importance of prior study comparisons • Image size, orientation, layout

3. Integration issues to be solved • Variances among vendors’ image data • Two types of image data • PACS may not provide all image data • Hanging may look different on workstations • CAD markers may look different on workstations • Add supplemental images • Change procedure information at Modality • Hide low-quality or incorrectly labeled images from further use

4. Mammography ImageUse Case Workstation Printer CAD “For Processing” Image Data Archive “For Presentation” Image Data Mammo CAD Structured Report Modality

5. Mammography Image ProfileValue proposition • Systems support DICOM objects • enhanced for interoperability/ quality aspects • FFDM modalities provide adequate information to facilitate downstream applications • Image display and printing operations enable safe, effective and efficient diagnoses • View and print images from multiple FFDM vendors consistently

6. Mammography Image ProfileActors & Transactions Digital Mammo X-Ray Image For Presentation, Mammo CAD SR Mammo CAD SR Digital Mammo X-Ray Image - For Presentation - For Processing

7. Acquisition ModalityEnable high-quality display, CAD, digitizer • Send both FOR PROCESSING and FOR PRESENTATION images with reference that ties them together • Additionally required DICOM attributes, e.g. • Acquisition date & time, operator’s name • Detector ID, software version • Exposure time, filter material, positioner angle • Detection and indication of tissue vs. air • Partial View Option - breast is larger than detector • Modified requirements for film digitizers

8. Image DisplayConsistent presentation & screen layout R CC L CC R MLO L MLO Calibration • DICOM Grayscale Standard Function (GSDF) Image hanging determined by: • View Type (i.e. CC vs. MLO) • View Type modifiers (i.e. Spot, Mag) • Laterality • Patient Orientation IHE does not use for hanging • Series or study descriptions • Image order as acquired • Image orientation as acquired

9. Image DisplayConsistent sizing also with different detectors R L R L R L L R Prior exam from vendor A’s system Current exam from vendor B’s system Different resolution Different pixel matrix Fit images to same size: • Relative • Physical • 1:1 pixels (detector : screen)

10. Image DisplayContrast, annotations, CAD marks Tissue vs. air detection: Window/ Center adjustments are not applied to air (pixel padding value/ range) Image annotations • Patient identification • Equipment identification • Technical factors • View: laterality, view type/ modifier CAD marks from Mammography CAD SR • One or more sets of CAD marks • Fit to image orientation • Information on CAD processing

11. Printing: Composer, Server Quality, annotations Minimal borders at chest wall • True Size printing - Requested Image Size • Justify chestwall - print with 5mm borders or less • Use display annotations Render VOI LUTs if present • Use Presentation LUT • Use maximum density • Support 12 bit pixel depth True size: less than 2% measurement error

12. Mammography Image Questions?

13. Mammo Acquisition Workflow Value proposition Now that I can create and consistently display Mammography images, how can “exceptions” of image acquisitions be handled and propagated more reliably at the Modality? • Clearly record what is performed at the Modality  coded values • Correctly and efficiently display images from acquisitions of separate procedure steps • Mark images of insufficient quality • Correct certain image labeling

14. Mammo Acquisition Workflow Actors & Transactions

15. Mammo Acquisition WorkflowSupplemental views to a completed exam MPPS forwarded MPPS in progress MPPS completed Query/ Retrieve screening and implant images Store suppl. images Archive Modality DSS/ OF * Workstation Supplemental implant displacement image after screening • Append case, where Modality fills protocol codes in a new MPPS.Modality supports Assisted Acquisition Protocol Setting. • Procedure unchanged, e.g. “Screening bilateral” Note: Compared to SWF, Modality always fills in protocol code(s). • Dept. Scheduler/ Order Filler may use protocol codes, e.g. notify user • Image Display selects presentation layout based on procedure/ protocol/ reason codes * Note: For simplicity reasons, the diagrams show the PPS Manager as part of the DSS/OF

16. Mammo Acquisition WorkflowFinish acquisition at another Modality Query MWL MPPS forwarded MPPS in progress MPPS completed Query/ Retrieve images from both Modalitiesas part of the same Study Store images Query MWL (patient-based) MPPS in progress/ completed Store images Modality 1 Archive DSS/ OF Workstation Modality 2 Supplemental images for one procedure acquired at another Modality • Avoid unscheduled acquisition with manual reconciliation • It all depends on DSS/OF worklist behavior • Does it keep COMPLETED/ DISCONTINUED workitems for some time? • Can workitems be queried more than once? • Modality queries Modality Worklist (MWL) based on patient name/ ID, Accession #, Procedure ID (independent of Modality “identity”)

17. Mammo Acquisition WorkflowConvert procedure MPPS in progress MPPSforwarded MPPS completed Query/ Retrieve imagesfor bilateral diagnostic exam Store images of R breast Archive Modality DSS/ OF Workstation Procedure update: unilateral  bilateral Convert diagnostic procedure: unilateral  bilateral • Radiologist reviews images of left breast while patient still present.Radiologist decides that images of right breast are needed, too. • Append case, where Modality fills in a new MPPS the codes for • The changed procedure: “Diagnostic Mammography, bilateral”. • Reasons for the changed procedure ( DICOM Change Proposal in work) • The appropriate acquisition protocol. Note: Compared to SWF, Modality always fills in procedure & protocol code(s). • DSS/ OF detects procedure change and updates Image Manager/ Archive.

18. Mammo Acquisition WorkflowRecall – patient returns for subsequent exam Query MWL (on recall) MPPS forwarded MPPS Query/ Retrieve images from original and recall study Store images (recall study) Archive Modality DSS/ OF Workstation Screening recall for a unilateral diagnostic mammogram • Radiologist assesses acquired images incomplete (BIRADS 0). Patient has left and needs to come back for additional imaging. • DSS/OF schedules a new procedure (as part of the screening order) with • a specific Reason for Requested Procedure code value • a reference to the original study (Referenced Study Sequence)  link between the original and the recall study • Regular acquisition at Modality • Image Display presents both studies based on reason code and study reference

19. Mammo Acquisition WorkflowUse of codes: DSS/OF, Modality, Archive • MAWF proposes 20 Procedure Codes (e.g. for Connectathon 2009) • MAWF requires 7 Procedure Reason Codes • DSS/OF must be able to fill in certain coded values • Modality is required to do Assisted Acquisition Protocol Setting • Image Manager/ Archive is not required to act specifically on these codes • Image Display is required to use codes for selecting presentation layout • Reason for Performed Procedure Sequence and some codes will become part of DICOM (Change Proposals in work: 881, 886, 904) • Operational necessity: code lists are synchronized between DSS/OF, Modality (and Archive) – no IHE-defined mechanism yet * Note: This table is not shown completely (see MAWF TI Profile text: Table 4.5-6)

20. Mammo Acquisition WorkflowReject images of insufficient quality PPS forwarded MPPS (Modality) orCreator PPS AvailabilityNotification Q/R A) Rejected images not part of query result Store rejection KOS Archive DSS/ OF Workstation Modality or QA workstation A) Rejected images are hidden B) Rejected images are hidden or displayed B) Rejected images are provided Mark images as rejected for quality reasons • After completed acquisition, images are considered of insufficient quality • Modality or Evidence Creator create a Key Object Selection (KOS) object • Document Title “Rejected for Quality Reasons” • Document Title Modifier is valued (DICOM PS 3.16, CID 7011) • References to all rejected images • Image Archive is configurable to provide or hide rejected images and KOS • Image Display is configurable to present or hide rejected images and KOS

21. Mammo Acquisition WorkflowCorrect view labels of images PPS forwarded MPPS (Modality) orCreator PPS AvailabilityNotification Q/R: incorrect imagesare not part of query result Store rejection KOSStore corrected image(s) Archive DSS/ OF Workstation Modality or QA workstation Incorrect images are hidden at Q/R View, laterality or protocol are corrected • After completed acquisition, incorrect view labeling is detected • Modality or Evidence Creator create corrected images • Copy most values except e.g. View Codes, View Modifiers, Laterality, Protocol • Correct references from “For Presentation” to “For Processing” images • Evidence Creator records its identifying data (Contributing Equipment Seq.) • Modality or Evidence Creator create a Key Object Selection (KOS) object • Document Title “Rejected for Patient Safety Reasons” ( DICOM CP) • References all incorrect images (For Presentation & For Processing) • Image Archive & Image Display hide KOS and the incorrect images

22. Mammo Acquisition WorkflowSummary • Scheduled Workflow extensions • Use of Protocol and Reason codes (DSS/OF, Modality) • Scheduled and performed Procedure Codes can vary.Never empty Procedure or Protocol Code Sequences. • Modality supports Patient-based Worklist Query • Image Quality Assurance results • “Low quality” images can be marked or hidden • Incorrectly labeled images can be corrected • Basic fault-tolerance against presentation of rejected/ incorrect images in Image Display

23. Questions?