1IHE Workshop – June 2006 What IHE Delivers

Todd Kantchev, Siemens Molecular ImagingTodd Kantchev, Siemens Molecular ImagingJerold Wallis, Mallinckrodt Institute of RadiologyJerold Wallis, Mallinckrodt Institute of Radiology

Kevin O’Donnell, Toshiba America Medical SystemsKevin O’Donnell, Toshiba America Medical Systems

Image Fusion ProfileImage Fusion Profile

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Image Registration and FusionImage Registration and Fusion

•Translate

•Rotate Rigid Registration

•Scale

•Warp- optional (Deformable Registration)

•Fuse

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Image Fusion- General Use CaseImage Fusion- General Use Case

Tech acquires two or more Tech acquires two or more series of images, possibly series of images, possibly separated in time.separated in time.

Tech reconstructs images into Tech reconstructs images into volumes, performs registration, volumes, performs registration, and stores results data.and stores results data.

Radiologist reads study or Radiologist reads study or Oncologist completes RT Oncologist completes RT planning on RT Planning planning on RT Planning System. System.

Referring Physician or Referring Physician or Researcher reviews results.Researcher reviews results.

CTCT MRMR

4IHE Workshop – June 2006IHE Workshop – June 2006

Fusion- The Integration ProblemFusion- The Integration Problem

Results not readily transferable between systems Proprietary or inconsistent implementations Lack of guidance

Results presented on different systems may not appear the same.

Systems must correctly handle issues such as Identifying and retrieving the right datasets Matching data between single-slice and multi-slice

datasets Performing spatial translations Rendering the fused display

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Fusion- The Integration SolutionFusion- The Integration Solution

A collection of DICOM objects exists to address the problem.

Their use is constrained and clarified to avoid misinterpretation and promote compatibility.

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Essential Clinical Features: MDs will be EcstaticEssential Clinical Features: MDs will be Ecstatic

MPR

Fusion

Side-by-side Registered

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Value PropositionValue Proposition

Interoperable DICOM encoding for registered/fused data

Consistent and reliable acquisition, storage and presentation of fused data across vendors

Allows separation of workflow steps: Acquisition on “A”; Fusion on “B”; Display on “C”

Wider distribution of results

Separable registration for re-doing if necessary

Can easily request basic interoperable fusion features. E.g. blended display, MPR, side by side display, etc.

Supports PET-CT (primary initial interest) viewing on general radiology PACS displays

Modality independent

Supports general needs in radiation oncology pre-planning

8IHE Workshop – June 2006IHE Workshop – June 2006

Image FusionImage FusionTechnical BasisTechnical Basis

Spatial Registration Object

Encodes transformation to align images in a common registered space

Identifies the registered space

References the images to be aligned

Not required for already-registered PET-CT data from a hybrid scanner

9IHE Workshop – June 2006IHE Workshop – June 2006

Image FusionImage FusionTechnical BasisTechnical Basis

Blending Presentation Object

References one set of underlying images (e.g. CT)

References one set of superimposed images (e.g. PET)

References (optionally) a Registration Object to align both image sets before blending.

Encodes the window level for each set

Encodes the blending factor (0 to 100%) of the overlay transparency

10IHE Workshop – June 2006IHE Workshop – June 2006

50%50%

Blending PresentationBlending PresentationOverlay TransparencyOverlay Transparency

20%

50%100%

80%

50%

11IHE Workshop – June 2006IHE Workshop – June 2006

Use Case- The IT SolutionUse Case- The IT Solution

Store CT

Store MR

Retrieve CT, MR

Register MR to CT

Store SRO

Store BSPS Retrieve CT, MR, SRO,

BSPS

Fuse CT and MR

Fuse CT and MR

Apply T to MR

Modality MRModality MRModality CTModality CT Image ArchiveImage Archive Evidence CreatorEvidence Creator Image DisplayImage Display

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Image Fusion Image Fusion Actors and TransactionsActors and Transactions

Acquisition Modality

Evidence Creator

Image Manager

↓ [RAD 18] Creator Images Stored ↓ [RAD 57] Blending Presentation States Stored↓ [RAD 56] Spatial Registrations Stored↓ [RAD 10] Storage Commitment

↓ [RAD 14] Query Images↓ [RAD 16] Retrieve Images↓ [RAD 15] Query Presentation States↓ [RAD 17] Retrieve Presentation States↓ [RAD 58] Retrieve Spatial Registrations

Image Archive

[RAD 8] Modality Images Stored ↓[RAD 57] Blending Presentation States Stored ↓[RAD 56] Spatial Registrations Stored ↓[RAD 10] Storage Commitment ↓

Image Display

13IHE Workshop – June 2006IHE Workshop – June 2006

Load CT and PET images

Align images (automatically or manually) and fuse with desired blending factor

Store the alignment, including

Registration object Blending State (defining the blending

factor, window levels and referencing all other objects)

Storage can be on PACS or disk. Images do not need to be stored if already stored.

Fusion- The Creating Process

Blending StateBlending StateBlending StateBlending State

Registration ObjectRegistration ObjectRegistration ObjectRegistration Object

CTCTCTCT

PETPETPETPET

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Blending state can be searched and retrieved from PACS Can be used to retrieve the image data

and the alignment automatically. User selects a Blending state. Automatically load the referenced CT and

PET images and the Registration object.Alignment can be applied, PET re-sampled to CT and displayed fused automatically .

Display is required to provide Scrolling through volume Adjustment of fusion blending and

window levels MPR Side-by-side display

Fusion- The Displaying Process

Blending StateBlending StateBlending StateBlending State

Registration ObjectRegistration ObjectRegistration ObjectRegistration Object

CTCTCTCT

PETPETPETPET

15IHE Workshop – June 2006IHE Workshop – June 2006