Quality Assurance in Diagnostic Radiology Flashcards
List some examples of general procedures that contribute to the quality assurance process.
- Critical examination.
- Performance testing.
- Maintenance.
- Clinical evaluation.
- Dosimetry audits.
Which regulations cover quality assurance and what do they state? What is the difference to quality control?
- IR(ME)R regulations cover quality assurance.
- They outline the requirement for QA programmes for equipment and for the testing of equipment before use and regularly and for regular maintenance.
- Quality assurance is the broader term covering all aspects of ensuring system quality. Quality control is the specific measures (e.g. machine performance tests).
Explain quality assurance and quality control.
- Quality assurance covers any planned and systematic actions necessary to provide confidence that a system or procedures will perform satisfactorily, safely and compliant with agreed standards.
- Quality control is a set of operations intended to maintain or improve quality including monitoring, evaluation and maintenance.
What is a critical examination, which regulations cover this and which staff groups are involved?
- A critical examination is a set of tests employed to ensure all safety features (e.g. receptor interlocks) and warning devices (e.g. warning lights) are functioning as expected to protect staff and the public (and, by proxy, patients) from exposure to ionising radiation.
- Critical examinations are covered by IRR17 regulations.
- The installer or erector of a piece of equipment is responsible for performing the critical examination or arranging for it to take place. A radiation protection advisor (RPA) must be involved (e.g. design the critical examination or review the results) and the critical examination is often sub-contracted to the RPA.
When are critical examinations performed in the equipment lifecycle?
A critical examination is performed following installation or after any major modifications that could have radiation safety implications (e.g. relocation, tube replacement etc.).
What types of equipment are covered by a critical examination?
Fixed room installations capable of producing ionising radiation are covered by the critical examination, as required as part of IRR17 regulations. Mobile equipment is not covered.
What are acceptance tests? Which staff groups are involved?
- Acceptance tests are the checks performed by a representative of the purchaser to verify that the contractor has provided all the equipment specified and has performed adequate tests to demonstrate that the specific requirements of the contract have been met.
- This typically comes in the form of a checklist with any discrepancies relayed to the contractor who must take appropriate remediate actions.
- They will include mechanical, electrical and radiation safety tests. This means that many different staff groups are typically involved in the acceptance process.
State the stages of the equipment lifecycle in order from installation. What is the range in lifetimes of this lifecycle for diagnostic equipment?
- Installation -> Critical examination -> Acceptance testing -> Commissioning -> Clinical use -> Routine performance testing and maintenance (-> Critical examination/commissioning if any major modifications) -> Disposal or alternate use -> Replacement ->
- Typical lifetime ranges from 7-15 years.
What is the purpose of commissioning tests? Which staff groups are involved?
- To ensure equipment is ready for clinical use (after installation or major modification) and to establish baseline values to compare back to during routine performance testing. Some of these tests may already have been performed as part of acceptance testing or the critical examination.
- Medical physics typically perform commissioning tests. However, end line users should also perform tests to acquire baselines for future local QA.
What tests are performed while equipment is in clinical use?
- Routine local QA tests and routine medical physics QA tests (these are typically a subset of commissioning checks to identify any changes in performance).
- Routine engineer maintenance.
- QA tests after routine maintenance, if equipment can not be put immediately back to clinical use (e.g. if there is potential for changes in dose).
- Critical examination/commissioning after any major modifications.
How can commissioning test results aid optimisation strategies?
- Results can be compared to guidance to guide optimisation of equipment.
- Results can be compared to other equipment to ensure they are optimised.
What are ‘Level B’ equipment tests? How often are these tests typically performed? What is done with the results of these tests?
- ‘Level B’ equipment tests are performed by medical physics. These are reasonably complex tests requiring specialist equipment (e.g. dosimeters and test objects).
- These tests typically follow a set protocol but experience in interpreting results and modifying tests when appropriate is required.
- These tests are typically performed routinely every 1/2 years depending on equipment.
- Results are gathered in a written report containing quantitative information on equipment performance, doses and image quality as well as written conclusions and any recommended actions.
What are ‘Level A’ equipment tests? How often are these tests typically performed? What is done with the results of these tests?
- ‘Level A’ equipment tests are designed to be simple (i.e. require minimal skills, equipment and time) and sensitive (i.e. will indicate an issue but not the casue) but, as a result, are not necessarily very specific. They concentrate on testing parameters which cover the greatest risks.
- These tests are typically performed daily/monthly depending on the equipment and test.
- Results are recorded and compared to action limits. A simple action plan should be available to follow in the event of test failure. This takes responsibility away from frontline staff.
What are remedial and suspension levels?
- Remedial level: Action is required but the equipment can be used in the mean time.
- Suspension level: Immediate action is required. The equipment (or part of it) should be removed from clinical use immediately.
What does IPEM 91 emphasise in terms of a QA programme’s supervision, testing time, test equipment, documentation and remedial actions?
- A senior radiographer or other suitable person should be appointed to supervise the QA programme.
- Time should be allocated to staff and equipment for testing.
- Test equipment should be available and within calibration.
- All QC results should be documented as part of the QA programme.
- Remedial actions should be followed up promptly.
