Working Group 7
(RT objects)
DICOM
Digital Imaging and
Communications in Medicine
Chairman:
David Murray Ph.D.,
TomoTherapy, Inc.
Email: dmurray@tomotherapy.com
Secretariat:
National Electrical Manufacturers Association
1300 North 17th Street, Suite 1847
Rosslyn, VA 22209 www.nema.org
Secretary : Stephen Vastagh, NEMA
ste_vastagh@nema.org
MINUTES
MEETING:
DICOM – Working Group 7
RT Objects
TIME:
PLACE:
October 10, 2002
ASTRO – Embassy Suites Hotel
New Orleans, LA
ORGANIZATIONS ON ROSTER REPRESENTED:
IMPAC Medical Systems
IMPAC Medical Systems
MDS Nordion
NOMOS Corporation
Nucletron
Philips Medical Systems
Siemens NMG
Siemens Oncology
TomoTherapy Incorporated
Varian Medical Systems
Scott Hogan
Andrea Morgan
Michael Neumann
Bruce Curran
Jaap Pijpelink
Harry Tschopik
Tom Milo
Satrajit Misra
David Murray
Ulrich Busch
OTHERS PRESENT
AKH Wien
NEMA
RAHD
ZMED, Inc.
Uwe Wolff
Stephen Vastagh
Robert Elens
Bruce Rakes
ORGANIZATIONS ON ROSTER NOT REPRESENTED:
Computerized Medical Systems
GE Medical
Merge Technologies
IBA
Optivus Technology, Inc.
Permedics
RadPharm
DICOM WG7 (RT Objects)
21
October 10, 2002
CHAIRMAN:
David Murray
TomoTherapy Incorporated
SECRETARY:
Stephen Vastagh
NEMA
1.
OPENING
The Chairman welcomed members and Mr. Wolff, a user guest from Austria.
The agenda was approved.
2.
MINUTES
The last meeting was held: July 18, 2002. No comments have been received on
the July 18 minutes, they are considered approved by correspondence.
Minutes of this meeting will be distributed within 30 days. If no substantive
comments are received within 30 days after receipt of minutes, they will be
considered approved by correspondence. This process facilitates having
approved minutes on the record rather than waiting until the next meeting.
3.
ROSTER OF THE WORKING GROUP
A roster was circulated for review and correction. The roster was also posted on
the ftp site. Corrections, updates should be sent to the Secretary.
4.
DICOM STANDARDS COMMITTEE REPORT
The most recent report of WG-7 to the DICOM Standards Committee is in Exhibit
A.
The WG-7 Profile, strategic document is posted on the DICOM web site.
5.
ION THERAPY SUB-GROUP
Michael Neumann, Chairman reported:
The Subgroup was very active at beginning of 2002, met efficiently, used web
meetings and phone conferences. In person meeting was held at PTCOG in
Catania, Italy. A presentation was made to PTCOG on the DICOM work.
Several additional persons from PTCOG participated in the Subgroup’s DICOM
meeting (May 28).
The standard development discussions are very difficult. Much time was spent
on discussions of the purpose: (a) transfer plan to treatment machine, or (b)
transfer plan to patient record, or (c) transfer plan from one treatment machine to
another. The technical issues are complex. There are only a few systems in
operation, all unique. The techniques are very complex.
DICOM WG7 (RT Objects)
22
October 10, 2002
Mr. Neumann further reported that the Subgroupd developed a “voting
document”, a list of items for possible inclusion (over 220 items). The Subgroup
discussed items in subsequent phone conferences. The list has been finalized.
Next steps:
It will be discussed to create a new draft supplement document in DICOM
terminology, distribute and further discuss. There are still unresolved issues with
beam modifiers: whether to include sequences. Another issue is whether to
include dosimetry data. It is expected to take 2 years to develop a supplement.
At the next meeting it will also be discussed to what level beam modifiers should
be implemented.
The following technical question still needs to be resolved: should various types
of beam modulation devices be encoded in a separate sequence, or coded up in
a generic sequence?
Mr. Hogan noted that there is also pressure in the market to include proton
treatment information in patient data. In order to move forward, it was suggested
to exclude beam modifiers, at this time. He further suggested considering
extending the SR concept and preparing a module. .
The Subgroup will schedule a phone conference in the near future. The Working
Group suggested that the Sub Group should work on a DICOM object (“frozen
but not standard”), to allow early prototype implementation. They may produce
an outline for the January WG 7 meeting.
7.
SUPPLEMENT 74: RT GENERAL PURPOSE WORKLIST EXTENSIONS
AND CALCULATION SERVICE MODEL
D. Murray had presented this to WG6, which supported the concept but had
comments. M. Neumann has updated the proposal following WG6 comments.
M. Neumann noted that new prescription objects need to be created.
There are some open issues, particularly use of N-CREATE. It was noted that
there is high interest in WG6, RT, and elsewhere.
There is a need to communicate with WG6 members.
ACTION:
8.
It was decided to hold the WG7 meeting concurrently with WG6,
January 8-9 and schedule presentation time with WG6 on Jan. 8
and Jan. 9. Phone conferences may be held in between times.
RT QUERY SUPPLEMENT
It was discussed that the status of Supplement number and work group status
needs to be checked.
ACTION:
Add to next meeting’s agenda.
DICOM WG7 (RT Objects)
23
October 10, 2002
9.
NEW CP: INNER CONTOURS
Key holing is currently used in DICOM standard. While not always appropriate for
display, this seems an appropriate and powerful strategy for communication of
data. Potential issues might arise with systems that perform point reduction, or
with dose calculation algorithms that trace down the area between the two very
closely spaced lines. A change proposal to clarify this interpretation at some
stage is appropriate.
ACTION:
10.
Mr. Curran to work up example note for next WG7 meeting.
FLUENCE MAP
Mr. Hogan reported that he reviewed the Elekta comments. It was discussed
whether this should be an RT Beams module as a sequence, or as a RT Image
of a special type, e.g. FLUENCE_MAP? Also could this be a calculated or
measured fluence map (do we need another attribute to describe this?). It was
discussed that this could be referenced at Beam level (beams module) or could
be added to RT Image.
The Working Group concluded that the latter is the best approach.
ACTION:
Mr. Hogan to continue new CP accordingly – RT Image. It will be
reviewed at the next WG7 meeting.
11.
CP 306 – Set to go before WG6
It was noted that those developing RT objects should be aware of this CP.
12.
CP 307– Set to go before WG6
13.
CP 308– Set to go before WG6
14.
New CP - Treatment Gating
This was previously discussed by David Murray. A potential module to indicate
breath/no breath, full/empty lung, and timing of radiation treatment to breathing
cycle needs to be discussed.
This was concluded to be a low priority issue and was tabled to the next meeting.
15.
New - CP – Introduce Phases into the RT Model
Elekta originally suggested this. Varian also confirmed its interest. Mr. Busch
summarized that the issue is how to spread the same prescription over several
plans. How to add doses without fusion is an issue.
ACTION:
Members to review the prescription module.
ACTION:
Mr. Busch to prepare a use case clearly describing any
shortcomings of current model. Discuss at next WG7 meeting.
DICOM WG7 (RT Objects)
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October 10, 2002
16.
NEXT MEETING:
Wednesday, Jan. 8, 2003 9:00 a.m.-5:00 p.m. (1 hr with WG6)
Thursday, Jan. 9, 2003, 8:30 a.m.-2:00 p.m. (2 hrs with WG6)
(RT Section Meeting 2:00 p.m.-5:00 p.m.)
Friday, Jan. 10, 2003, 8:30 a.m.-12:00 noon
Place: NEMA Offices, 1300 N. 17th St, Suite 1847
Arlington, VA 22209
For directions and hotel accommodations see
http://www.nema.org/index_nema.cfm/582
15.
ADJOURNMENT
The meeting was adjourned at 4:30 p.m.
Reported by
Stephen Vastagh
October 25, 2002
Reviewed by Counsel: Oct. 28, 2002
DICOM WG7 (RT Objects)
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October 10, 2002
Exhibit A:
Report to DICOM Committee on WG7 (Radiotherapy) Business
David Murray, September 15, 2002
Since the last WG7 report to the DICOM Committee (June 11, 2002), a WG7
(RT) Meeting was held on Thursday July 18, 2002 in Montreal (during this
year’s AAPM).
A significant number of RT-related CP’s were discussed at this meeting, as
reported in the WG7 meeting minutes. Currently three CP’s (306,307,308)
are ready for presentation to WG6, and will be presented whenever a
WG7 representative is available to attend. A number of other CP’s are
nearing completion and will be ready for introduction following the next
WG7 meeting.
The Ion Therapy subgroup has been active in developing a new proposal. This
work is ongoing, and will continue at a subgroup meeting at ASTRO.
The NEMA RT Section Meeting (held the same day as the WG7 Meeting)
discussed the topic of DICOM demonstrations at AAPM and ASTRO in
2003. This discussion was continued in WG7, and subsequently in a
phone conference. The current plan is to demonstrate connectivity of RT
Structure Set, RT Plan, and RT Image objects, and develop publicity
material and hold a seminar on the show floor(s). This project also has the
support of the AAPM Computer Committee. Planning will continue at the
ASTRO WG7 Meeting.
An issue was raised regarding the importance of providing patient position
information in PET images that are to be used in radiation therapy. It
appears that often this information is not provided in PET images.
Communication with WG6 and WG3 is ongoing to determine how to
encourage the passing of this information.
The next WG7 will be held at ASTRO (New Orleans), Thursday October 10,
2002.
David C. Murray, PhD
Director of Product Development
TomoTherapy, Inc.
1240 Deming Way
Madison, WI 53717-1954
Tel: (608) 824 2821
Email: dmurray@tomotherapy.com
DICOM WG7 (RT Objects)
Minutes, July 18, 2002