Transcript Quality Control in CT, a teamwork - 2015 Joint Congress on Medical

Quality Control in CT, a Teamwork
Manon Rouleau ing., Karine Bellavance t. i. m., Ali Nassiri Ph. D.,
May 28 – 30, 2015, Montréal, Québec
Disclosure Statement: No Conflict of Interest
I do not have an affiliation, financial or otherwise, with a pharmaceutical company, medical
device or communications organization.
I have no conflicts of interest to disclose ( i.e. no industry funding received or other
commercial relationships).
I have no financial relationship or advisory role with pharmaceutical or device-making
companies, or CME provider.
I will not discuss or describe in my presentation at the meeting the investigational or
unlabeled ("off-label") use of a medical device, product, or pharmaceutical that is
classified by Health Canada as investigational for the intended use.
May 28 – 30, 2015, Montréal, Québec
2015 Joint Congress
on Medical Imaging
and Radiation Sciences
Collaborative Care – Imaging and Treatment
Au service du Réseau
Montreal, May 30th 2015
Quality Control in CT, a Teamwork
Manon Rouleau ing., Karine Bellavance t. i. m., Ali Nassiri Ph. D.,
Learning Objectives
 Understand the value of quality control in CT
 Be aware of and access publications, tools and training
provided by CECR
 Integrate quality control practices in CT in one’s practice
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Quality Control: Logic and benefits
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Why doing Quality Controls?
 Ensure adequate performance of the facility
 Prevent avoidable artefacts, that might interfere with diagnosis
 Avoid dose increase to patients due to unnoticed performance
degradation.
 Screen problems, plan repair and maintenance to avoid cancellation
of patients appointments
 Maintain diagnostic quality of images for optimum patient dose
(ALARA principle)
 Ensure users and patients safety
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Avoidable Artifacts
CR artifacts due to cracks on imaging plate
Dead pixel that can be mistaken for calcification
Shetty et al.. American Journal of Roentgenology. 2011
Geiser et al.. American Journal of Roentgenology. 2011
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Avoidable Artifacts
Hyperattenuating artifact, observed on two different patient CT exams,
that disappear after recalibration of the scan
Cody, Stevens & Ginsberg, Multi-Detector Row Ct artifacts That Mimic Diseases,
Radiology , Sep 2005; Vol.236: 756–761 , 10.1148/radiol.2363041421
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Avoidable Artifacts
Artéfacts causés par un détecteur défectueux
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Avoidable Artifacts
Ring artifact on a brain CT:
caused by inaccurate matching and intercalibration of the detectors
Al-Shakhrah et al.,Common artifacts in Computerized Tomography: A review,
Applied Radiology, August 2003
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Detection of Artifacts during daily QC,
calibration and stability testing
Before calibration
After calibration
Cody, Stevens & Ginsberg, Multi-Detector Row Ct artifacts That Mimic Diseases,
Radiology , Sep 2005; Vol.236: 756–761 , 10.1148/radiol.2363041421
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Calibration and stability QC test for CT
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Improved
patient’s safety
Performance
criteria & QC
Physicists
Collaboration &
Retroaction
Radioprotection
awareness
Practice’s
improvement
Updated
Procedures
Continuing
Education
Continuing
Follow-up
Technologists
Physicians
Correctives
Actions
Engineers
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Publications
 To facilitate the integration of good practices in radiation safety,
by medical imaging team
 To facilitate standardized practices in radiation safety
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Quebec’s Guidelines on quality control and
radioprotection in medical imaging
A guideline composed of modules, for a progressive approach:
– CT scan's quality control and radiation safety
– CT scan’s acceptance and commissioning (in preparation)
– Roles & responsibilities in quality control and radiation safety
in medical imaging (in preparation)
– Conventional radiography’s & fluoroscopy’s quality control and
radiation safety (in preparation)
– Conventional radiography’s & fluoroscopy’s acceptance and
commissioning (to come)
– Radiation safety in interventional imaging (to come)
– Mammography’s quality control and radiation safety (to come)
– Good radiation safety practices in medical imaging (to come)
Progressive implementation,
modality by modality
Towards the implementation of a
National Radiation Protection Program in medical imaging
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Module’s considerations
Take into account:
 Health Canada recommendations
 International recommendations
 Scientific publications
 Quebec's current practices in radioprotection as well
as in performance assessment of medical equipment
 Best recognized practices in radiation protection
and quality control
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Objectives of these guidelines
 Upgrade of quality control's and radioprotection practices in medical
imaging;
 Standardize performance assessment methodology and the quality
criteria's in medical imaging;
 Provide tools to hospitals and local imaging teams, that allow them to:
 Monitor the performance of medical imaging systems and the application of
radiation protection practices, in their daily work;
 Ensure to make the needed adjustments and improvements, at the right time;
 Improve the quality and radioprotection culture, within the teams and
establishments;
... To continuously provide
quality medical imaging services, highly safe
and ensure better protection for patients.
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CT scan’s quality control and radioprotection
Module
Periodic quality controls
&
Good radioprotection practices, for :
 Technologists
 Physicists and engineers
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Authors
 M. Jean Arsenault, ing., IUCPQ, Québec
 M. Jacques Blanchette, med. phys., IUCPQ (retired), consultant, Québec
 Mme Francine Dinelle, med. phys., HGJ, Montréal
 M. Clément Drolet, ing., CHUQ (retired), Québec
 M. Gilbert Gagnon, t. i. m., Cégep de Sainte-Foy (retired), consultant,Québec
 M. Normand Nadon, med. phys., HSC (retired), Montréal
 M. Moulay Ali Nassiri, med. phys., CECR, CIUSSSE-CHUS, Sherbrooke
 Mme Manon Rouleau, ing., CECR, CIUSSSE-CHUS, Sherbrooke
 M. Nagi Sharoubim, ing., MUHC (retired), consultant, Montréal
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Overall Content
 Section 1 : Synthesis of all CT QCs
 Presented by frequency and responsibility
 Section 2 : Medical imaging technologists
 4 Daily tests
 3 quarterly tests
 1 biannual tests
 3 yearly tests
 Section 3 : Physicists and Engineers
 9 annual tests
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Daily tests
Test description
Overall state of equipment
Check presence, cleanliness and integrity
CT calibration and stability
Daily required calibrations and overall CT stability.
Functioning of the indicators
Adequate functioning of all indicators, on the console and gantry
Acquisition and reconstruction console performances
Overall calibration of acquisition and reconstruction monitors
Responsibility
Section
MIT
2.1
MIT
2.2
MIT
2.3
MIT
2.4
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Quarterly tests
Test description
Access Control
Make sure access control mechanisms to the CT room are adequate and functional.
Personal Dosimetry
Make sure workers’ exposition are ALARA.
Responsibility
Section
MIT
2.5
MIT or RSO
2.6
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Bi-annual Test
Test description
CT Monitors Performances Evaluation
Evaluate all reading stations used to read CT images.
Responsibility
Section
MIT, BMET, physicist or
engineer
2.8
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Yearly tests
Test description
Responsibility
Section
MIT
2.8
MIT or RSO
2.9
2.10
Check availability of up to date technical and software CT information.
MIT
&
Physicist or Engineer
Other tests
Physicist or Engineer
Preventive maintenance logbooks check
Make sure preventive maintenance was done and corrective measures taken.
Protection clothing check
Check presence and integrity of protective clothing
Information
3.1
3.2 and
following
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Required Material
 Manufacturer Water Phantom
 * TG18-QC, TG18-CT, TG18-UN, TG18-UNL and TG18LN12 patterns
•
•
Note (1): Use DICOM 2k patterns format
Note (2): Use a DICOM format that will ensure 1 :1 ratio between image pixel and displayed pixel.
 Periodic Dosimetry reports
 Preventive maintenance logbooks and correctives actions details
 Quality control registry
*TG18 test patterns are used for quality control on monitors and were developed by the Task Group 18 of the American
Association of Physicists in Medicine (AAPM) . They are protected by copyright. However, they can be obtained free at the
following address: http://deckard.mc.duke.edu/~samei/tg18
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Test Structure
Example: Functioning of the indicators
 Goal : Ensure adequate functioning of all indicators on console and gantry.
 Frequency : Daily
 Required material : Non-applicable
 Methodology : Check indicator function and commands on the console, gantry and
control panel ; fill out the report.
 Compliance criterias :
 Each control is operational.
 Each indicator is functional.
 All displays are visible and normal.
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Training – Education
To Develop and upgrade skills
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French trainings adapted and available at all times
CT equipments and quality controls:
 TDM : aspects technologiques, techniques et optimisation (1)
 TDM – CQ et radioprotection (conférences multiples) (1)
 Contrôles de qualité en tomodensitométrie - Volet technologue
en imagerie médicale et moniteurs diagnostiques(1)
Radioprotection:
 La réduction des doses aux patients en TDM, une approche
multidisciplinaire et collaborative(1)
 Positionnement et utilisation des caches au Bismuth en TDM
(1) Available on www.FormaZone.ca, in collaboration with OTIMROEPMQ, for all professionals.
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Adapted QC follow-up tools easily accessible
 Outil de suivi des contrôles de qualité
TDM - volet TIM
 Outil de suivi des contrôles de qualité
TDM - volet stations diagnostiques
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Question
The implementation of a QC program in a medical
imaging department decreases productivity.
Studies have shown that the QC program increases productivity. It
allow detection of performance degradation as well as inadequate
operation, which leads to a better planning of corrective actions,
reducing unplanned downtime and consequent cancellation of
examinations.
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Question
The CECR recommend that the calibration and
stability test be performed weekly.
It is recommended to do the calibration and stability
test daily .
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Question
If, during the daily QCs, the results of the calibration and
stability test, fail to meet the conformity criteria, the MIT must
immediately inform the BME Service and stop using the CT.
The MIT must first repeat the calibration in the air and then
redo the QC test. If the problem persists, then he informs the
BME Service of the situation and discusses with them
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regarding the corrective actions to be taken.
Question
The biannual QC verification of CT reading stations must be
performed only by a physicist or engineer.
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Questions
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To reach us
 Phone: 819 348-3842 ou 1 877 839-1217
 Fax: 819 822-6700
 e-mail: [email protected]
 mail: CECR
500, rue Murray, case postale 1
Sherbrooke (Québec) J1G 2K6
Internet page: www.chus.qc.ca/cecr
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