DICOM WG10 and ISO TC215
WADO Work Item Planning
Joel Chabriais/Cor Loef
co-chair DICOM Strategic Advisory
Committee
Limitation of WADO
• One SOP Instance only in one call (no way for
retrieving all the series/study)
• Suited for Web Browser based solution, less
for direct with applications
• The URL based query is easy to write, but not
adapted for being parsed
• No easy way to help the application
development through WSDL
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WADO in WS, which form?
• IHE ITI wrote White Paper on WS
implementation, based on WS-I
• The XDS.b Retrieve Document Set transaction
is similar to WS/WADO
• All the WADO query parameters can be
directly transposed « as is » in WS
• The response structure can be derived from the
Retrieve Document Set structure
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WADO WS Interaction
Web Enabled
DICOM
Server
Web Client
System
Object(s) request
(GET/POST HTTP Request)
[Metadata and] Object(s) send
(HTTP Response to the GET/POST
Request)
4
WADO WS Response
5
WADO « brothers »
• WADO implies to have the reference
• A notification mechanism may be developed
on WS (NADO)
• A Query by IDs mechanism may enable an
application to obtain the reference (QIDO)
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NADO Notification of Availability of DICOM Objects
• WADO is supposing the Application retrieving the DICOM Object(s) is
aware of it/their existence and availability. But no mechanism has been
provided for informing the application that such DICOM Instance(s) are
available.
• Similarly to the DICOM IAN (Instance Availability Notification), a WS
based transaction may be defined for notifying the availability of DICOM
Object(s). It addresses similar use cases than some targeted by the ISO
TC215/WG2 “WARM” work item and it may correspond to an evolution
of this one.
• The mechanism may imply a “subscription” by an application to be notified
at different levels (study/series/instance) and the notification message may
include, in addition to UIDS, at least the Patient Id, the Accession Number
and the Modality.
• The Application may be implementing a WS server (so the DICOM system
will act as a client to notify it) or as a WS client (so it has to query regularly
or use the asynchronous mode of WS).
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QIDO Query based on ID for DICOM Objects
• Similarly to the IHE ITI Retrieve Document for
Display (RID) transaction, the Application can query
the DICOM server to have a list of available DICOM
objects.
• Parameters may be similar to those used for RID
(Patient ID, date(s) and number of most recent) with
the Accession Number (in addition to the Patient ID
required for security reasons).
• The Application will act as a WS client, while the
DICOM Server will act as a WS server.
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Proposed Joint Approval
August
DICOM
Part 18
29th
WG6
2010
WADOWS
Supplement
to Part 18
DICOM
Public
Comment
45
days
Aprilh
WG6
2011
WADOWS revised
Supplement
to Part 18
DICOM
Ballot
49
days
WG6
March 2011
DICOM
Part 18
WADO+
WADO-WS
Reformat
WADOWS
Supplement
to Part 18
ISO
ISO-DIS
15+60
days
ISO-IS
WADO-WS
+ WADO
15+150
days
WADO+
WADO-WS
WADO IS
Authorize
Issue of CD ?
ISO CD
Ballot ?
2011
February 21, 2011
TC215 Plenary
May, 13st 2010
ISO DIS
Ballot
April 9th
2011
TC215
May 2011
9
??
2011
WADO-WS Workitem
• WADO-WS to be submitted to DICOM WG6
approval for public Comment release late August
2010.
• Need to organize the joint approval process
between ISO TC215 and DICOM.
• Assumptions are:
– a single standard will be published that includes both
WADO and WADO-WS in DICOM and ISO.
– Current WADO in DICOM (Part 18) and ISO (IS12974)
need to be superseded by the combined existing
WADO & new WADO-WS document when approved.
Februay 21, 2011
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