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DICOM WG-02 DICOM WG-02 Advances in X-Ray Angiography Advances in X-Ray Angiography

Projection Imaging and 3DProjection Imaging and 3D

SPIE Medical Imaging2010, San Diego

Authors: Heinz Blendinger Siemens Healthcare Bas Revet Philips Healthcare Francisco Sureda GE Healthcare (Chair DICOM WG-02)

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IntroductionIntroductionOverview of X-Ray Angiography in DICOM

X-Ray N-Dimensional Presentation X-Ray N-Dimensional Presentation CasesCases

3D Shutter

Volume Subtraction

Stabilized Region in Moving Volume

Trajectory Tracking in Volume

2D-3D Blending

ConclusionConclusion

Presentation OutlinePresentation Outline

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Overview of X-Ray Angiography in Overview of X-Ray Angiography in DICOMDICOM

2D Projection Images2D Projection Images

X-Ray AcquisitionX-Ray Acquisition

3D Reconstruction3D Reconstruction

Approved in the

Standard

Work in Progress

Supp 94:Radiation Dose

Reporting

Supp 83:Enhanced XA/XRF

Supp 116:X-Ray 3D Storage

Supp 139-LB: Enhanced XA

Informative Annex

N-Dimensional Presentation State

Follow-up of IHE REM Profile

CR-DX Dose Reporting

Supp 140: Presentation State

X-Ray 3D Informative Annex

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Workflow in X-Ray N-Dimensional Workflow in X-Ray N-Dimensional PresentationPresentation

X-Ray 3D X-Ray 3D Reconstruction Reconstruction

SystemSystem

X-Ray Calibratio

n Procedure

Calibration Data

Proprietary

X-Ray X-Ray Acquisition Acquisition

SystemSystem

3D Visualization 3D Visualization SystemsSystems

X-Ray Acquisitio

n Procedure

Enhanced XA

Storage SOP Class

X-Ray 3D Storage

SOP Class

Reconstruction

Procedure

N-D Presentation

State SOP Class

In progress

Visualization Visualization

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X-Ray 3D Angiography X-Ray 3D Angiography – Rotational – Rotational AcquisitionAcquisition

Frame #5:X-ray settings 5

Geometry settings 5

Frame #2:X-ray settings 2

Geometry settings 2

Frame #3:X-ray settings 3

Geometry settings 3

Frame #4:X-ray settings 4

Geometry settings 4

Frame #1:X-ray settings 1

Geometry settings 1

Optimized 3D Reconstruction

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X-Ray 3D Angiography X-Ray 3D Angiography – Presentation – Presentation StateState

Needs for 3D Angiography Presentation– Presentation features common to all 3D modalities (rendering...)– Speficic presentation of X-Ray 3D Angiography:

• Acquisition 3D shutter (e.g. collimation)• Volume Subtraction and voxel shift• Stabilized point in all volumes (e.g. cardiac wall motion, stent stabilized)• Catheter tracking trajectory in one volume• 2D-3D blending presentation (3D conic projection on 2D fluoroscopy)

N-Dimensional Presentation State• Work Item 2008-04-C. Addresses needs of multi-modalities• Led by Working Group 11, participation of Web3D Consortium and other DICOM working groups• Supplement in progress...

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X-Ray 3D Angiography X-Ray 3D Angiography – Presentation – Presentation StateStateVolume Regions to define 3D shutter

Punch Hole: EV: “ELLIPSE“ or “POLYGON“Plane: Orientation, Position, inside or outsideFrame: EV: “ELLIPSE“ or “POLYGON“ or “BITMAP“

Proposal for Volume Region Sequence:• Region Purpose : DT: “DISPLAY SHUTTER“ or “ROI“• Region Display Mode : DT: “DISPLAY“ or “HIDE“• Region Definition Method : Enumerated Values• ...

Punch Holes Clipping Planes Frames

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X-Ray 3D Angiography X-Ray 3D Angiography – Presentation – Presentation StateStateVolume Subtraction

Proposal for 3D Mask Subtraction Sequence:

• Mask Operation: DT: “Volume Selection“• Applicable Volume: Pair of Frame Numbers (e.g. N+1, N+k)• Mask Volume: Pair of Frame Numbers (e.g. 1, N)• Mask Voxel Shift: Triple of Float Numbers• Mask Contrast Registration 4x3 matrix• Mask Operation Explanation: Free Text• Mask Selection Mode: DT: SYSTEM or USER• Recommended Viewing Mode: DT: SUB or NAT

Mask Frames Contrast Frames

SubtractedContrast

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X-Ray 3D Angiography X-Ray 3D Angiography – Presentation – Presentation StateStateStabilized region in moving volume

Applicable to 4D data (i.e. 3D volumes with time)Goal: Stabilize the position and orientation of an object during the dynamic view

The result is an animated sequence to view the volumes stabilized at a given point:

• a) with same volume orientation• b) or changing the orientation of the volume to keep the same orientation of the object of interest

Proposal for Stabilized Region Sequence:// contains as many items as number of volumes

• Applicable Volume: Pair of Frame Numbers• Point: 3D coordinates• View Angle: 3D view angle

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X-Ray 3D Angiography X-Ray 3D Angiography – Presentation – Presentation StateStateTrajectory Tracking in Volume

During the planning phase of a catheterization intervention

• Define a 3D curve from point A to point B inside an artery (i.e. catheter trajectory)

• Define an animated sequence to view the progress of the curve:

Applicable to 3D dataGoal: View the volume along a pre-defined trajectory of the camera

Example:

a) from the outside of the volume, with same volume orientation

b) from the outside of the volume, changing the orientation of the volume to be perpendicular to the tip of the curve

c) from inside the artery (fly-thru) as virtual endoscopy

AA

BB

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2D-3D Blending in X-Ray Angiography 2D-3D Blending in X-Ray Angiography (1/2)(1/2)

X-Ray X-Ray AcquisitioAcquisition Systemn System

X-Ray Rotational Acquisition X-Ray 2D

Projection SOP Class

X-Ray 3D Storage

SOP Class

X-Ray 3D Reconstruction

3D Segmentation

Segmentation SOP

Class

X-Ray Acquisitio

n

2D-3D BlendingX-Ray 2D Projectio

n SOP Class

3D View 3D Viewing Settings

Conic Projection2D Presentation3D Presentation

new

2D Presentati

on SOP Class

Same Frame Of Reference

2D View

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2D-3D Blending in X-Ray Angiography 2D-3D Blending in X-Ray Angiography (2/2)(2/2)

X-Ray X-Ray AcquisitioAcquisition Systemn System

CT Storage SOP Class 3D

Segmentation

Segmentation SOP

Class

X-Ray Acquisitio

n

2D-3D BlendingX-Ray 2D Projectio

n SOP Class

3D View 3D Viewing Settings

Conic Projection2D Presentation3D Presentation

new

2D Presentati

on SOP Class

2D View

3D Image (CT, …)

Registration to Isocenter

System

new

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ConclusionConclusionEnhanced XA (2D)Enhanced XA (2D)

Supplement 139Supplement 139 in Letter Ballot. Informative (DICOM Part 17)

Will facilitate the adoption of the Enhanced XA SOP Class (Sup 83)

XA Presentation State (2D)XA Presentation State (2D) Supplement 140Supplement 140 in Final Text

X-Ray 3D AngiographyX-Ray 3D Angiography New IOD approved in Standard 2007 (Supplement 116Supplement 116)

Application cases (Informative) - Work In Progress

N-D Presentation StateN-D Presentation State N-D Presentation State - Work In Progress

To get involved in WG-02 developments: contact chairman at

francisco.sureda@ge.com