powerpoint presentation by Dr Ivan Williams

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Transcript powerpoint presentation by Dr Ivan Williams

Verification of Practice: Maximum safety and minimum risk for patient Beyond Bricks and Mortar 11/08/2011 Dr Ivan Williams Director ACDS


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.


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


generic cause

Calibration and use of radiation measurement system

number of accidents

4 15 Commissioning/calibration of treatment unit 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 (QLD) Romauld Gajewski (NSW) Caroline Knipe (Tas.) Chris Hamilton Annette Haworth Mathew Murray (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.


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

Reporting to the organisation

Your Beam is 0.7 % high with a 2 x sigma of 4.2 %

Risk Profile: Centre



Auditor Infrequent Authority measurement Centre Frequent 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


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


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

Courtesy R.Ganesan, P Harty.

Standards Lab II

Courtesy R.Ganesan, P Harty.

Standards Lab III

Radiological Physics Centre 5% – 6% of US megavoltage beams > ±5% (TLD) 125/537 (22%) US institutions fail to meet irradiation criteria with anthropomorphic phantoms


18 %


31 %


50 %