powerpoint presentation by Dr Ivan Williams

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Verification of Practice:
Maximum safety and minimum risk
for patient
Beyond Bricks and Mortar
11/08/2011
Dr Ivan Williams
Director ACDS
Congratulations!
You have a new centre/machine
It is now opened
The ribbon is cut
A crowd gathered
The press took photos
And now they have gone
It’s time to get to work and treat.
Question
How do you know that your metrics:
Weight / Rate / Volume / Amount / Dose /
Dose-rate / Energy/ Positioning / Imaging /
Distortion / Data transfer / etc etc
Are correct?
Internal QA/QC programs
Quality Control
Quality Assurance
But:
generic cause
Calibration and use of radiation
measurement system
number of
accidents
4
Commissioning/calibration of
treatment unit
15
Commissioning and use of
treatment planning system
11
Internal systemic errors
1045
patients
ACDS: Rationale
The number of patients and fields treated with
therapeutic radiotherapy within Australia is increasing
every year – population trends indicate that this demand
will continue to increase
There is convincing international evidence demonstrating
that external, independent dosimetric verification of
radiotherapy centres improves the accuracy of the
treatment delivery.
ACDS: Establishment I
In July 2010, the Australian Government funded a trial
initiative to provide external, independent dosimetric
verification for Australian radiotherapy centres: The
Australian Clinical Dosimetry Service, ACDS.
The ACDS will be operated by ARPANSA, under a
memorandum of understanding, MOU.
The ACDS will be based at Yallambie, the radiation
Primary Standards Laboratory, Melbourne, utilising the
dosimetric expertise within.
ACDS: Establishment II
3 Levels of free audit service to be developed in
consultation with, and delivered to, the radiotherapy
community over 3 years
Analysis of the service will be conducted in the third year
to determine the outcomes of the ACDS
A decision will be made whether to continue, modify or
terminate the program based on the outcomes
i.e. continuation of the service is NOT a given
ACDS: Staffing
ACDS staff will consist of
Director
Appointed
Dr Ivan Williams
Consultant
Appointed (0.2)
A/Prof Tomas Kron
Physicists
2 FTE
Mr John Kenny (F/T  P/T)
Dr Jessica Lye (P/T)
Dr Joerg Lehmann (F/T)
Administrative 0.5 FTE
To be advertised in 2011
ACDS: Structure I
The MOU requires a Clinical Advisory Group, CAG,
which will consult into the ACDS. The CAG will consist of
individuals from the various stakeholders:
RORIC
ACPSEM
AIR
RANZCR
TROG
AAPROP
Roger Allison
Romauld Gajewski
Caroline Knipe
Chris Hamilton
Annette Haworth
Mathew Murray
(QLD)
(NSW)
(Tas.)
(Vic.)
(Vic.)
(QLD)
RO
MP
RT
RO
MP
MP
ACDS: Structure II
The MOU requires an auditing group drawn from the 3
professions to;
• assist ACDS staff while reducing travel costs,
• provide additional technical advice during site visits,
• ensure site visits take place according to procedures,
• assist the professional development of radiotherapy
facility staff on the Audit Panel,
• provide the profession with greater participation in the
ACDS project, and
• provide an informal path of feedback into the ACDS
project.
Audit designs
Level II
T.Kron et al., Int. J. Radiation Oncology Biol. Phys., Vol. 52, No. 2, pp. 566–579, 2002
Level 1: OSLD
An independent measurement of linear
accelerator output at one point under reference
conditions in a regular homogenous phantom
Level 2
An independent measurement of linear
accelerator output at multiple points in multiple
beams. The phantom will contain
inhomogeneities and wedged fields will be
investigated.
IAEA Pub 1297, IAEA-TRS430, IAEA-TECDOC-1583, ESTRO Booklet No.7,
IAEA-TECDOC-1543, Kron et al. (2002), Ebert et al. (2009)
Level 3
An independent measurement for a specific
treatment area. An anthropomorphic phantom
section will be CT imaged, contoured, planned
and treated following to a defined protocol.
Level 3
IAEA-TECDOC-1583, ICRU 62.
Reporting to the organisation
Your Beam is 0.7 % high with a 2 x sigma of 4.2 %
Risk Profile: Centre cf Auditor
Auditor
Centre
Infrequent
Frequent
Authority measurement
Normal
Consequences of error are thus very different:
False Positive & False Negative
Mammo defn
Minimise risk: ARPANSA
Level 1: Results to date
Level 1: By Linac
To-date
Formal launch
Level I audits operational and planned to 2013
Level Ib direct calibrations operational.
Mail out to centres for contacts (90+ % return)
Website database development
Staff arrived
Level II and III draft protocols written – field testing
arranged
OSLD commissioning on-going
Acknowledgements
John Kenny
Leon Dunn
Jessica Lye
Tomas Kron
Abel MacDonald
Alison McWhirter
Tracey Rumble
Ramanathann Ganesan
Peter Harty
David Webb
Duncan Butler
Chris Oliver
Dave Webb
Standards Lab I
Standards Lab II
Courtesy R.Ganesan, P Harty.
Standards Lab III
Courtesy R.Ganesan, P Harty.
Radiological Physics Centre
5% – 6% of US megavoltage beams > ±5% (TLD)
125/537 (22%) US institutions fail to meet irradiation
criteria with anthropomorphic phantoms
Pelvis
Lung
Liver
Spine
18 %
31 %
50 %
25%
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