A Working Group of Our Own (DICOM WG-26) Bruce Beckwith, MD Department of Pathology Beth Israel Deaconess Medical Center Harvard Medical School Boston, Massachusetts

Current State

Future State

Outline DICOM overview DICOM pathology support Use in Pathology Issues to address

DICOM D igital I maging and Co mmunications in M edicine Initially drafted as jointly sponsored effort of the American College of Radiology and the National Electrical Manufacturers Association (ACR-NEMA), which became the DICOM committee in 1998 Ver. 1 released 1985 –Physical 50 pin hardware abstraction layer standard –Never implemented Ver. 2 released 1988 –Initial interest from radiological manufacturing community only DICOM V3.0 released 1992 Visible light supplement 1999 (endoscopy/microscopy)

DICOM Governance Voluntary standards group Housed at NEMA in Virginia Currently 26 working groups Participants –Industry –Professional and trade groups –Standards developing bodies and government agencies –Anyone who has a material interest

Pathology in DICOM Visible Light working group was initial home Created Supp. 15 Minimal pathology activity since then Dec 2005, created a new group for Pathology (WG-26)

Working Group 26 Open to all interested parties 3-4 meetings per year 70+ subscribers to the mailing list 35+ organizations 9 countries Working with IHE (Japan and France) and HL7 Pathology groups

DICOM Supplement 15 Support for –gross images –microscopic images –accession numbers –case history –SNOMED TM nomenclature and others –some imaging system specifications –compatible with all DICOM database systems

How DICOM is Used To communicate between image sources (radiographic instruments) and PACS To communicate between PACS and display workstations To communicate between RIS and PACS To communicate between image sources and enterprise image archive

Image Exchange DICOM standard is for communication related to digital images Uses externally defined file formats to encode the image data Includes metadata with the image data Uses an object oriented data model 16-part standard document –

Typical VL Message Components Header Constructs Patient demographics Study capture parameters Equipment parameters Pixel/voxel dimensions Diagnostic data Image Data Primary image plane data Overlay data Arbitrary waveform data ROI data Diagnostic ROI-localized modifier data Access/authentication/watermark data Service Class Wrapper Optional Components Structured Reporting Data Self-referential XML schemata Clinical Data Specimen Data Tissue Array Data Research Access data Clinical Trial Data Chain of custody data …………………. Ancillary Schemata/DTD definitions Ancillary XML

Picture Archiving & Communication Systems Store images acquired by multiple instruments Serves images to various workstations Uses DICOM for messaging Typically only utilized for radiology images May have workflow limitations

Enterprise Image Archive Centralized storage for medical images Share across many departments Not limited to radiology or even DICOM Not tightly coupled to any workflow Can be write once – read many (no deletion)

Imaging Comparison Radiology –digital acquisition –automatic image capture –clinician interpretable –many patient requests –large storage needs –digital images save money –large budgets –strong standards for storage and transfer Pathology –analog primary data –manual image capture –hard to interpret for non- pathologists –few patient requests –extreme storage needs –digital imaging costs more –modest budgets –limited pathology specific standards

Current State in Pathology Many PACS vendors are compliant with Visible Light images for pathology, endoscopy, etc. Growing number of imaging products targeted at pathology are DICOM compliant Anatomic pathology laboratory information systems offer limited image management Veteran’s Administration: Pathology imaging vendors must be DICOM compliant and store images in VISTA PACS Small, but growing adoption of DICOM

Barriers to Adoption of Current Products Turf –PACS systems have traditionally been the domain of Radiology –Movement toward storing all medical images in a central location with a single viewing mechanism still in infancy Workflow –May need to manually annotate files with image description, accession number, etc. –If sending to PACS, need to order study first Cost –Image acquisition and annotation takes time – no extra reimbursement currently –Slide scanners and storage are costly

Path PACS Humin Tec (Korea) –PACS system for pathology departments –21 installations, all in Korea –Communicates with standard radiology PACS –Also offers station for specimen photography Apollo Telemedicine (USA) –PACS system allows acquisition and storage of images –Installed at Milwaukee Veterans Administration Hospitals –Images can be stored in VISTA imaging system

Academic Center Efforts Univ. of Pittsburgh –AP LIS is image aware –Gross specimen photos and single field microscopic images saved –Transmitted to Enterprise Image Archive –Clinicians can see only selected images on completed cases –Main clinician interest is specimen photos –Main pathologist use is conferences

Issues to Address Technical –Need for additional data elements (block, slide, slide status, more detailed imaging system description, etc.) –Support for whole-slide microscopic images DICOM is limited to 64k x 64k pixel images currently –Support for multi-resolution (pyramidal) formats –Support for navigating and selecting a region of interest from within entire slide image –Support for multispectral and hyperspectral modality images Non-technical –Suggested workflow and use examples (IHE) –Support for DICOM from LIS vendors

Resources DICOM web site: medical.nema.org RSNA DICOM Intro Medical Imaging FAQ: