Transcript RADCIS Status Report and 3yr Plan August 1, 2005

Work Item
for
Web Based DICOM
Jim Philbin/Cor Loef
Co-chairs WG27: Web Technology in DICOM
Healthcare Trends
Customer Issues with Imaging
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Enterprise Imaging
• Images must be available across enterprise
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All providers
All locations (hospitals, clinics, offices, homes, …)
Imaging studies coming from many different specialties
Need one aggregated imaging record
Multiple PACS/mini-PACS, many different workflows
Multiple Viewers/Workflow (by specialty)
Study size increasing
• DICOM push model complicated & expensive
• Moving studies outside of data center slow
(to a diagnostic or modality workstation)
Customer Interoperability Problems
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Upgrades (changing vendors) impeded by migration
Multiple viewers <-> one image archive
• Most viewer use proprietary interface to proprietary local
cache that talks DICOM archive [DICOM push]
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Multiple Mini-PACS and modality workstations
• Most mini-PACS use proprietary interface to proprietary local
cache that talks DICOM archive [DICOM push]
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Thick client apps difficult & expensive to maintain
Work Item Goal
The Web is the technology that has arguably
had the greatest impact on our society
in the last 20 years.
The goal of this Work Item is to enable the
efficient transport, storage and display
of DICOM studies though an HTTP interface
thus allowing applications to leverage Web
technologies to deliver DICOM data.
Work Item
Sub-Goals
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Web based transmission, storage and display
of DICOM studies
PACS independent Web based DICOM Storage
• Eliminate the need for PACS migrations
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Support the DICOM information model and IODs
without modification.
Interoperability between viewers, PACS, VNA/PNA, etc.
Leverage Web Technologies
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Web server infrastructure to support DICOM
Enables interoperability
Use web technologies for:
• Automatic re-direction
• Routing, Caching and Storage
• Replication, failover and load balancing
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Allow DICOM to track technology evolution
Enable browser based applications to lower costs
• Deployment & maintenance
• Anytime, anywhere availability
Web Based Transmission
of DICOM Studies
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DICOM information model and IODs unchanged
Transmit all or part of a study in one message
• Ease of access to study metadata
• Eliminates end of transmission time-out problem
• Storage commit (http header)
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Extensible to non-DICOM objects using standard
Web technologies
Web Based Interface
to DICOM Storage
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Single interface supports
• Long Term Archive, Caches, Routers
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Addressing by studyUIDs
Ability to fully index a DICOM store
Storage commit is inherent in protocol
Enables support for multiple PACS
Enables Elimination of PACS migrations
Enables Store once and distribute
MINT
Web Based DICOM Storage
MINT is designed for the efficient transport and storage
of DICOM objects using Web technologies
Modalities
Viewers
Viewers
Modalities
typically
proprietary
DICOM
PACS
PACS
MINT Store
MINT
Essence of MINT
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Efficient encoding of DICOM IODs for use with HTTP
• Studies are normalized, i.e. no metadata duplication
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Study create, read, update, delete, copy, move
using HTTP
DICOM objects addressed by URI’s using UIDs
All or part of a study can be transmitted in one message
Backup Slides
Problems MINT Addresses
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Study size increasing
• Time to display images increasing
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Multiple mini-PACS w/ separate caches
• Speed
• Proprietary data
• Increases complexity
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DICOM Push model
Migrating the archive when changing vendors
Need for enterprise archive
Logical View of the MINT Encoding of DICOM
•Metadata
• Includes all non binary attributes found in all DICOM SOP
instances in a given study
• Normalized attributes according to DICOM Information
Model
• Is accessed independently from the binary data
• References binary data items using their id
•Binary Items
• Can be retrieved in batch or individually
• Are identified by study scoped ids (bids or binary ids)
Patient
Voice Clip
Private Attributes
x
Image
Study
Series
Series
Series
SOP Instances
SOP Instances
SOP Instances
Metadata
Binary Data
How MINT is Different from WADO
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Focused on DICOM transport & storage using HTTP
No support for rendered (e.g. JPEG) objects (only
DICOM)
Normalized metadata
Creates, Updates and Deletes DICOM studies
Uses REST style resources rather than parameters to
identify studies, series and SOP instances
DICOM->MINT->DICOM
Isomorphic
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DICOM->MINT
MINT->DICOM
Conformance tests are part of reference
Proposed
MINT Operations
Study Create
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Study Create
POST <s>/studies/create [content]
-> <studyUID>
Note: <s> = <service>
POST mint.jhu.edu/studies/create [content]
Read
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Study
GET <s>/studies/<studyUID>
-> <study>
GET <s>/studies/<studyUID>/<seriesUID>
-> <series>
GET <s>/studies/<studyUID>/<seriesUID>/<objectUID>
-> <sop instance>
Read (cont)
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Study Summary
GET <s>/studies/<studyUID>/DICOM/summary.ext
-> <summary>
Study Metadata
GET <s>/studies/<studyUID>/DICOM/metadata.ext
-> <metadata>
Where
.EXT = XML, XML.gz, GPB, GBP.gz
Read (cont)
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Study Binary Items
GET <s>/studies/<studyUID>/DICOM/binaryitems
-> [binary items]
Study Read Report
GET <s>/studies/<studyUID>/DICOM/reports.ext
-> [DICOM SR]
Study Read ChangeLog
GET <s>/studies/<studyUID>/DICOM/changeLog
-> [changeLog info]
Update
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Get Update Lock
POST <s>/studies/<studyUID>?lock=true
-> <lock>
Update Study
POST <s>/studies/<studyUID>?lock=<lock> [content]
-> [status msg]
Move, Copy & Delete
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Study Copy
POST <s>/studies/<studyUID>?action=copy; target= <URIorCon>
-> [status msg]
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Study Move
POST <s>/studies/<studyUID>?action=move; target= <URIorCon>
-> [status msg]
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Study Delete
DELETE <s>/studies/<studyUID>
-> [status msg]
Study Search
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Study Search
GET <s>/studies/search?<query>
-> [search results]
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Query Parameters
StudyUID, IssuerOfPatientID, PatientID,
IssuerOfAccessionNumber, AccessionNumber,
ModalityTypes, MinStudyDate-Time, MinStudyDate,
MaxStudyDate-Time, MaxStudyDate
Other Backup Slides
A Study’s History
Time
5 min
1 Hour
P10
Instance
P10
1
Instance
P10
2
Instance
P10
3
Instance
P10
4
Instance
P10
5
Instance
P10
6
Instance
P10
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Instance
8
P10
Instance
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Instance
P10
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Instance
P10
11
Instance
P10
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Instance
P10
13
Instance
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Series 1, 2 & 3
(From Modality)
Series 4
(From Modality
2 Days
P10
Instance
15
HL7 - PID
Need to
update all
instances in
all caches
with this
change
Patient Name Change
(From HIS)
Presentation State Added
(From Viewer)
• Studies are not created at one single point in time
• New SOP Instances may be added to a study at any time
• Changes to existing instances may be made at any time
MINT is Web Based
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RESTful interface to DICOM studies
• Transport = HTTP 1.1 (includes chunking)
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Leverages existing technologies
Transmission through firewalls
• Encoding XML
• Operations
CRUD (Create, Retrieve, Update, Delete)
Search
Notification
• Data Model = DICOM Part 3
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Leverages existing web technologies
Allows transmission through firewalls
Current Status
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MINT Reference Implementation of Version 1.0
available at www.GOTMINT.org
4 vendors are implementing products
3 more vendors have committed to implement
Currently working on version 1.1