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Consistent Presentation of Images - Integration Profile. Ellie Avraham Kodak Health Imaging IHE Planning and Technical Committees. Scheduled Workflow. Admit, order, schedule, acquire images, notify of completed steps. Patient Information Reconciliation.
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Consistent Presentation of Images - Integration Profile Ellie Avraham Kodak Health Imaging IHE Planning and Technical Committees
Scheduled Workflow Admit, order, schedule, acquire images, notify of completed steps Patient Information Reconciliation Unknown patients and unscheduled orders ConsistentPresentation of Images ConsistentPresentation of Images Hardcopy and Softcopy Image Consistency Hardcopy and softcopy grayscale and presentation state IHE Integration Profiles HIMSS / RSNA
Consistent Presentation of Images Objectives • Consistent distribution of Images across the healthcare enterprise • Consistency among Hardcopy Images Printed on different Printers (from different Vendors). • Consistency among Softcopy Images view on different Display devices (from different Vendors). • Consistency among Hardcopy and Softcopy Image view • This IHE Integration Profile is the cost effective solution to ensure that image quality is maintained across different monitors and film producing devices. HIMSS / RSNA
Consistent Presentation of Images Requires: 1 • Calibration of the Softcopy Display and the Hardcopy Output Devices using DICOM Grayscale Standard Display Function • Creating Hardcopy Output Using DICOM Basic Print with Presentation LUT Support • Saving the Softcopy Display Viewing Parameters using DICOM Grayscale Softcopy Presentation State 2 3 HIMSS / RSNA
The Grayscale Image Presentation Problems: Device capabilities/ characteristics vary * Device Luminance range * Display Characteristic Curve:DDL -> Luminance * Device Display Resolution: Non-Standard Interpretation of Pixel value to Output Device Luminance HIMSS / RSNA
The Grayscale Consistency Problem: • The appearance of grayscale images displayed on different types of softcopy display devices or printed on different types of hardcopy output devices is in general inconsistent and at times may impact clinical perception HIMSS / RSNA
The Grayscale Consistency Problem: • Optimal image viewing parameters (e.g. window/ level) selected on one device appear different when displayed on a different device • Device capabilities/ characteristics vary - the same number of gray levels cannot be rendered or perceived on different devices • Displayed images look different from printed images • …other HIMSS / RSNA
Problems of Inconsistency • VOI chosen on one display device • Rendered on another with different display • Mass expected to be seen is no longer seen mass visible mass invisible Slide Provided by David Clunie HIMSS / RSNA
Problems of Inconsistency 0.5 1.0 • Not all display levelsare perceivable on alldevices 1.5 3.0 Slide Provided by David Clunie HIMSS / RSNA
Problems of Inconsistency 0.5 1.0 • Not all display levelsare perceivable on alldevices 1.5 3.0 Slide Provided by David Clunie HIMSS / RSNA
Digital Modality Laser Printer Problems of Inconsistency • Printed images don’t looklike displayed images Slide Provided by David Clunie HIMSS / RSNA
Causes of Inconsistency • Display devicesvary in the maximumluminance they canproduce • Display CRT vs. film on a light box is an extreme example 1.0 .66 Slide Provided by David Clunie HIMSS / RSNA
Standardize Display Systems to Achieve Grayscale Consistency, Hardcopy Output and Softcopy Viewing Devices Have to Be Properly Calibrated The DICOM Standard Defines: A standard curve, the Grayscale Standard Display Function (GSDF), against which different types of display and hardcopy output devices should be calibrated 1 HIMSS / RSNA
The GSDF Standard Characteristic Display Systems Curve The GSDF transformation defines the mapping of the P-values to the view Luminance or optical density value, and preserving the Human perceptual response, based on the Human Contrast Sensitivity. 1 HIMSS / RSNA
Printer Calibration Tools (Densitometer) HIMSS / RSNA
Display Calibration Tools (Photometer) HIMSS / RSNA
Grayscale Standard Display Function 1000 Film 100 10 Monitors 1 0 200 400 600 800 1000 .1 .01 JND Index DICOM GSDF Slide Provided by David Clunie HIMSS / RSNA
Grayscale Standard Display Function Despite different change in absolute luminance 1000 100 10 1 0 200 400 600 800 1000 .1 .01 JND Index Same number of Just Noticeable Difference == Same perceived contrast Perceptual Linearization Slide Provided by David Clunie HIMSS / RSNA
Monitor Characteristic Curve Monitor Characteristic Curve 100 10 0.1 Ambient Light 0.01 0 50 100 150 200 250 300 Digital Driving Level Slide Provided by David Clunie HIMSS / RSNA
Grayscale Standard Display Function 1000 Maximum Luminance + Ambient Light 100 Monitor’s Capability 10 1 0 200 400 600 800 1000 Minimum Luminance + Ambient Light Jmax == P-Value of 2n-1 .1 Jmin == P-Value of 0 .01 JND Index Standard Display Function Slide Provided by David Clunie HIMSS / RSNA
100 Standard 10 1 0 50 100 150 200 250 Characteristic Curve 0.1 DDL or P-Values Standardizing a Display Slide Provided by David Clunie HIMSS / RSNA
Mapping P-Values to Input of Characteristic Curve (DDL’s) 300 250 200 DDL 150 100 50 0 0 50 100 150 200 250 300 P-Values Standardizing a Display Slide Provided by David Clunie HIMSS / RSNA
To Achieve Consistent Presentation of Images, the DICOM Standard Defines: • Basic Print Management with Presentation Look Up Table, for controlling the consistent appearance of preformatted images on printed output 2 HIMSS / RSNA
Rescale Slope/Intercept or Modality LUT Window/Level or VOI LUT Presentation LUT Presentation LUT Transformation Original Image M o d a l i t y M a s k V O I L U T L U T Grayscale Transformations ( S u b t r a c t i o n ) T r a n s f o r m a t i o n T r a n s f o r m a t i o n S h u t t e r P-Values Display T r a n s f o r m a t i o n I m a g e D i s p . A r e a S p a t i a l Shutter, Annotation and Spatial Transformations T r a n s f o r m a t i o n A n n o t a t i o n A n n o t a t i o n DICOM Grayscale Image Transformation Model e HIMSS / RSNA
Association Negotiation - “Contract Agreement” Agreed set of SOP Classes and Transfer Syntaxes ( Basic Print Meta SOP Class) Print (SCP) Print (SCU) Basic Print Meta SOP Class consist of four SOP Classes (Film Session, Film Box, Image Box, and Printer) N-Create (create film sheet, format printer) Film Sheet N-Set (place images on film sheet) N-Action (request to print the film sheet) N-Event-Report (status of the printer) Basic Print Management Meta SOP Class Slide Provided by Don Van Syckle HIMSS / RSNA
Basic Print Request with Presentation LUT Print Print Composer Server Print Composer Print Request DICOM Film Session N-CREATE DICOM Presentation LUT N-CREATE DICOM Film Box N-CREATE DICOM Image Box N-SET DICOM Film Box N-ACTION DICOM Film Session N-ACTION Print Server Print Status (DICOM N-EVENT-REPORT) Printer Status HIMSS / RSNA
Print Composer 23 Print Request withPresentation LUT Print Server Basic Print Request with Presentation LUT • IHE Transaction - a Print Composer Actor issues a DICOM Print request to a Print Server Actor. The Print request includes a Presentation LUT for display consistency. HIMSS / RSNA
Basic Print Request with Presentation LUT • Print Composer – A system that generates DICOM print requests as a DICOM Print SCU. Print composer has to apply image processing manipulations, and requests to Print server will specify P-Values in the form of Presentation Look-Up Tables (Presentation LUTs) or implicitly by Presentation LUT Shape. • Print Server – A system that accepts and processes DICOM print requests as a DICOM Print SCP and performs image rendering on hardcopy media. The system must support pixel rendering to optical density according to the DICOM Grayscale Standard Display Function. HIMSS / RSNA
Basic Print Request with Presentation LUT • Required transaction for both Print Composer and Print Server Actors • Print Composer shall be grouped with one of the following: • Acquisition Modality Actor • Image Manager Actor • Image Display Actor • Image Creator Actor HIMSS / RSNA
To Achieve Consistent Presentation of Images, the DICOM Standard Defines: 3 • Grayscale Softcopy Presentation State (GSPS), an object for storing and communicating the parameters that describe how an image or set of images should be displayed. A GSPS object contains references to the images it applies to, and the transformations (grayscale transformations, shutter transformation, image annotation, spatial transformations, and displayed area annotation) that should be applied when the images are presented on a softcopy display, or printed on film. HIMSS / RSNA
Area Of Interest Area Of Interest Achieving Consistent Presentation Flip Zoom Annotate Original Image Without Consistent Presentation Window Level Consistent Presentation of Images Referring Physician or Reviewing Radiologist Reporting Radiologist Presentation State Presentation LUT Grayscale Standard HIMSS / RSNA
IE Module Usage Patient Patient M Study General Study M Patient Study U Series General Series M Presentation Series M Equipment General Equipment M Presentation Presentation State M Modality LUT C - Required if to be applied Mask C - Required if multi-frame and to be applied VOI LUT C - Required if to be applied Softcopy Presentation LUT M Graphic Annotation C - Required if to be applied Spatial Transformation C - Required if rotation, flipping or magnification are to be applied Displayed Area M Display Shutter C - Required if to be applied and the Bitmap Display Shutter Module is not present Bitmap Display Shutter C - Required if to be applied and the Display Shutter Module is not present Overlay Plane C - Required if to be applied or the BM Displ. Shutter Module is present Overlay/Curve Activation C- Required if image contains curve or overlay which is to be displayed Graphic Layer C - Required if Graphic Annotation or Overlays or Curves are to be applied SOP Common M GSPS Module Table: HIMSS / RSNA
Grayscale Softcopy Presentation State: • Composite object containing the image display settings parameters • Composite object links to one or more images (Series, filters); stored using same Study Instance UID (same Storage SOP Class!) • Uses regular Storage services (C-STORE); uses Query/Retrieve services • GSPS SOP Instances are immutable: changes require a new SOP Instance UID • Note: generation and specific application of GSPS is outside the scope of DICOM, but not outside the scope of IHE (e.g. Presentation of Grouped Procedures) HIMSS / RSNA
GSPS Stored, and Query/Retrieve GSPS Image Display Image Creator 15 Query Presentation State 19 Creator Presentation Retrieve Presentation State 17 State Stored Image Archive 9 Modality Presentation State Stored Acquisition Modality • IHE Transaction - an Acquisition Modality or Image Creator Actor sends a DICOM GSPS C-STORE request to an Image Archive Actor • IHE Transaction - an Image Display Actor issues a C-FIND request to an Image Manager Actor • IHE Transaction - an Image Display Actor issues a C-MOVE request to an Image Archive Actor HIMSS / RSNA
Creator Presentation State Stored Image Creator Image Archive C-STORE (Presentation State Stored) HIMSS / RSNA
Query for Grayscale Softcopy Presentation States Image Archive Image Display Query/Retrieve Presentation States (C-FIND/C-MOVE) Presentation States (C-STORE) HIMSS / RSNA
Attribute Name Tag Query Keys Matching Query Keys Return SCU SCP SCU SCP Presentation Label (0070,0080) O O R+ R+ Presentation Description (0070,0081) O O O R+ Presentation Creation Date (0070,0082) O O R+ R+ Presentation Creation Time (0070,0083) O O R+ R+ Presentation Creator’s Name (0070,0084) O O R+ R+ Referenced Series Sequence (0008,1115) O O R+ R+ >Series Instance UID (0020,000E) O O O R+ >Referenced Image Sequence (0008,1140) O O O R+ >>Referenced SOP Class UID (0008,1150) O O O R+ >>Referenced SOP Instance UID (0008,1155) O O O R+ IHE Year 4: Presentation State Specific Query Matching and Return Keys HIMSS / RSNA
Consistent Presentation of Images Print Display Acquire Slide Provided by David Clunie HIMSS / RSNA
Questions? Documents Available On the Web at: www.rsna.org/IHE or www.himss.org HIMSS / RSNA