DICOM INTERNATIONAL CONFERENCE SEMINAR April 8 10 2008

DICOM INTERNATIONAL CONFERENCE & SEMINAR April 8 -10, 2008 Chengdu, China Efficient, Standard-Compliant Streaming of EHR Imagery Combining JPIP and WADO within an XDS-I Framework Lev Weisfeiler Aware, Inc. Co-chair DICOM WG 4 (Compression) DICOM to JPEG liaison www. aware. com/medical

The need for a standardized streaming technology is emerging as regions/countries deploy image-enabled EHR

Introduction – EHR, XDS-I • Many countries are implementing image-enabled EHRs • IHE XDS-I is an effective solution for publication and discovery of patient diagnostic imaging history across multiple enterprises – Physical access to data requires DICOM transfer from one PACS to another • Relatively slow due to multiple transactions and DICOM over the WAN • Complexities introduced from copying data between PACS – “ingesting foreign data” problem • DICOM configuration can become unmanageable in a regional setting • IHE XDS-I is emerging as the prevailing interoperability architecture – Some countries are promoting compliance to the IHE Profile – Some projects are not concerned about the compliance to standards, but see the profile as an effective solution to the interoperability problem

XDS - Overview • Objective of XDS – To support document sharing between enterprises in different care settings and organizations • XDS “Publish and Subscribe” paradigm – – Create a persistent “document”… images, reports, etc. Publish the document to the a “repository” Register the document in an “index” “Consumers” query the index to find out about documents and where they are stored – Consumers retrieve documents “on-demand” from the repository

XDS-I – Key Concepts • Users reference images at the “exam” (study) level – Users do not reference images at the “image” level • XDS-I needs to “publish” and “index” a document that represents the “exam”… not the image • Requires a level of abstraction, namely an image “manifest” – The manifest is a document with a list of pointers to the images that it represents – The manifest is a DICOM KOS object

Motivation - Image Streaming • To achieve access to image data within the EHR and maintain acceptable performance, projects need content delivery techniques with streaming technology • WADO is a means to address many of the DICOM related challenges in an image-enabled EHR – WADO provides HTTP-based method of access to DICOM objects – Consumers discover the URL to images through XDS-I and can thereby retrieve images via HTTP through WADO – Limit the use of DICOM to communications between modalities and PACS • JPIP offers standardized “on-demand”, streamed access to image data – Streaming technology allows fast image display over lower bandwidth networks – Standard enables any viewing client to access data from any JPIP server

JPIP - Overview • Standardized image streaming • JPEG 2000, Part 9 – ISO/IEC 15444 -9 – ITU-T Rec. T. 808 • Included in DICOM – Supplement 106 • Efficient transmission of JPEG 2000 data over varying bandwidth networks – JPEG 2000 provides high quality, DICOM-compliant, wavelet-based image compression – JPIP is the blueprint for the best usage of JPEG 2000 functionality in a distributed application environment

JPIP Streaming Use Cases • Stack navigation of a large CT study – Low resolution preview – Full fidelity imagery available on demand • Large single image navigation – Pan/zoom region of interest at display resolution • Thumbnail representation for a study – Sub-resolution image easily extracted • Display by dimension – Random access to individual frames of a large enhanced multiframe object

DICOM Access Example 1) 2) 3) 4) 5) Patient presents at emergency room (ER) User requests data (through XDS-I discovery and retrieve) Copy image data via DICOM C-MOVE Data ingestion and preparation Image display using local PACS proprietary protocols Consumer (ER) XDS Registry/Repository D M ICO DICO M DICOM Image Manager/Archiv

WADO/JPIP Access 1) Patient presents at ER 2) User requests data (through XDS-I discovery and retrieve) XDS query (ITI-16) • HTTP-SOAP with SQL text • Responds with candidate documents and associated URI Consumer (ER) XDS Registry/Repository XDS document retrieve (ITI-17) • • HTTP transaction Returns DICOM KOS object Image Manager/Archiv

WADO/JPIP Access 1) Patient presents at ER 2) User requests data (through XDS-I discovery and retrieve) 3) WADO request for image data Parse the DICOM KOS “manifest” • Extract the URI to series Consumer (ER) WADO http GET • Use the URI from manifest to initiate a XDS Registry/Repository WADO Get • Define transfer syntax to be JPIP http T GE GE T p t t h http GET Image Manager/Archiv

WADO/JPIP Access 1) 2) 3) 4) Patient presents at ER User requests data (through XDS-I discovery and retrieve) WADO request for image data Image data streamed to viewing client using JPIP Local PACS IM/IA supports WADO • WADO server includes JPIP server Consumer (ER) Stream data from JPIP enabled PACS to viewing client XDS Registry/Repository • Viewing client supports JPIP Image Manager/Archiv

Remote Viewing • Web based image viewing client – Access manifest (KOS) via WADO – Request images in manifest through WADO with a JPIP transfer syntax – Stream image data from JPIP enabled PACS to client

Summary - Benefits Combining XDS-I/WADO/JPIP • Standards based data discovery across multiple PACS (XDS-I) • Fast image access over WAN without the need for – DICOM configuration – DICOM transfer – Foreign data ingestion into PACS • All standard-compliant; no proprietary protocols • Leverage ubiquitous security environment • Client and servers can be from different vendors

Acknowledgements Thank you to Dr. Peter Bak for his contribution – – The Chair of the Pan-Canadian Standards Working Group for DI Director of architecture for DI at Canada Health Infoway Primary author of the pan-Canadian XDS-I standard Primary author of the “JPIP adoption as a pan-Canadian standard” initiative

Acronyms • • IHE – Integrating the Healthcare Enterprise EHR – Electronic Health Record XDS-I – Cross Enterprise Document Sharing for Imaging WADO – Web Access to DICOM Objects JPIP – JPEG 2000 Interactive Protocol PACS – Picture Archiving and Communication Systems KOS - Key Object Selection WAN – Wide Area Network