Quality Assurance 2024-2025 PDF

Quality Assurance FUNDAMENTALS OF RADIATION AND RADIATION SAFETY MODULE TIMELINE 2024-25 Mock...

Quality Assurance FUNDAMENTALS OF RADIATION AND RADIATION SAFETY MODULE TIMELINE 2024-25 Mock Assessment Seminar Seminar Seminar 3 1 2 MCQ Exam Lecture Lecture Lecture Lecture 2 4 6 7 Lecture Lecture Lecture Lecture Lecture Lecture 1 3 5 8 9 10 Holidays SEPTEMBER OCTOBER NOVEMBER DECEMBER JANUARY Virtual 1 3 December 2024 Simulations Quality Assurance 2 2 1 3 On-Campus Simulations 2 TOPICS KEY: Skills for module Fundamentals of completion Radiation Radiation Safety Radiation Protection Assessment Skills & in Context Assessment Module Learning Objectives  Understand the Become familiar Understand benefit importance of with types of QA of QA testing quality assurance tests required Introduction to remedial and suspension performance levels December 2024 Quality Assurance 4 Song of the week! How good is it really ⓘ Start presenting to display the poll results on this slide. Quality Assurance Requirements What do you understand by the word ‘quality’? Why is quality assurance important? QA - we HAVE to do it  We HAVE to do it IRR 17 Reg 33 (3) – (4) “Every employer… shall…make arrangements for a suitable quality assurance programme… for the purpose of ensuring that it (the equipment) remains capable of restricting exposure so far as is reasonably practicable to the extent that this is compatible with the intended clinical purpose or research objective” IRMER 17 Reg 15 https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcT3l6HFZb9ftWu7uRqQb0h-FjdKZE-UcfMVEg&usqp=CAU An employer who has control over any equipment must… Implement and maintain a quality assurance programme in respect of that equipment…. When must we do QA? Before any new equipment is used for clinical purposes Even before applications training! At suitable intervals Special attention should be given to equipment… involving high doses such as … CT… After major maintenance Even if this doesn’t involve parts which are directly relevant to radiation protection of the patient  Tests performed by representative of the purchaser – usually Medical Physics To ensure equipment performs as per specification To ensure equipment is ready for clinical use To establish baseline (reference) values To confirm that requirements of IRR Reg 33 are met December 2024 Quality Assurance 12  The value of a parameter, which is determined at the commissioning of an imaging system, against which the results of subsequent performance tests can be compared Set baseline values for each test that will be performed routinely December 2024 Quality Assurance 13  Regular To detect any A subset of Performed by: Compare performance changes in the the Radiographers against (constancy) system’s commissioning Medical Physics baseline values testing performance tests December 2024 Quality Assurance 14 Major maintenance? What do you think would constitute major maintenance of an item of X-ray equipment? Major maintenance Replacement of, or changes to: X-ray tube, collimators, filters, generator (HV tanks), detectors… Boards? Reconstruction PCs? Software upgrades? QA needed after all of these QA should be performed after every Engineer visit Routine QA tests IPEM Report 91 Published 2005 Lists routine QA tests and tolerances on results Currently being revised… Two levels of testing Level A: More frequent tests; quick and simple pass/fail tests. No sophisticated equipment required. Generally undertaken by Radiographers Level B: Less frequent, more analytical tests. Requires greater equipment resources. Generally undertaken by Medical Physics staff Priority 1 – minimum standard Priority 2 – best practice to include The recipe book IPEM Report 32 I 3rd Edition Published 2022 More details on how to perform tests and why certain tests are necessary/useful  Which exposure parameters? In order to compare like with like… Need to keep all acquisition parameters the same kV, mA, exposure time (mAs) Focus to detector distance Collimation  Documentation Results must be documented as part of the QA programme CQC Inspector wants to see proof that you’re doing QA, that results are within tolerance (when compared with a baseline value) and action is taken when tests fail Quality Assurance Tests Alignment and distance  Level A tests Test No Physical parameter Frequency Priority RAD01 X-ray to light beam alignment 1-2 monthly 1 RAD02 X-ray to light beam centring 1-2 monthly 1 RAD03 Light beam to bucky centring 1-2 monthly 1 RAD04 Light beam field size calibration 1-2 monthly 2 RAD05 Distances and scales 1-2 yearly 2 RAD07 Radiation output – repeatability 1-2 monthly 1 RAD08 Radiation output – variation with mA / mAs 1-2 monthly 1  Level B tests Test No Physical parameter Frequency Priority RAD09 Radiation output – repeatability 1-2 yearly 1 RAD10 Radiation output – variation with 1-2 yearly 1 mA / mAs RAD11 Exposure time 1-2 yearly 1 RAD12 Tube potential 1-2 yearly 1 - Half value layer X-ray and light beam alignment Why might it be important that the radiation field is well aligned to the light beam, and that their centre points match up? https://www.healthpages.org/wp-content/uploads/hand-x-ray.jpg X-ray to light beam alignment Light beam used to indicate size and location of X-ray field Used to position every patient Important that the two are well aligned IPEM 32 Part 1 X-ray to light beam alignment - testing Place beam alignment plate on top of detector Set 100 cm focus to detector distance Adjust light field to the white lines Make exposure at low kV/mAs – view resulting image IPEM 32 Part 1 X-ray to light beam alignment - results Remedial level: misalignment > +/- 1cm Suspension level: misalignment > +/- 3 cm IPEM 32 Part 1 X-ray to light beam centring - testing Test at same time as beam alignment Place Perspex cylinder on top of alignment plate Cylinder contains ball bearings at top and bottom Make exposure at low kV/mAs – view resulting image IPEM 32 Part 1 X-ray to light beam alignment - results Remedial level: misalignment > +/- 1cm @ 1m IPEM 32 Part 1 Light beam to bucky centring - testing Perform the above test with detector in bucky Use ‘detents’ to ensure tube is centred to detector Make exposure at low kV/mAs – view resulting image IPEM 32 Part 1 Light beam to bucky centring - results Remedial level: misalignment > +/- 1cm @1m https://radiationsafe.co.za/wp-content/uploads/2016/05/6.3.4-Test-4-8-Alignment-collimation.pdf Light beam field size - testing Rarely performed as a separate test – can combine with previous tests https://qualitycontrolradiography.weebly.com/uploads/4/6/3/3/46333503/5320868_orig.jpg Distances and scales Why might this be important? https://chesapeakemedicalsystems.com/wp-content/uploads/FDR-Visionary-Suite-Tube-head-1.jpg Distances and scales Influences image contrast, distortion, magnification Also affects radiation dose Set to standard values for specific examinations https://chesapeakemedicalsystems.com/wp-content/uploads/FDR-Visionary-Suite-Tube-head-1.jpg Distances and scales - testing Measure actual source to detector distance with tape measure Compare with indicated value Remedial level - +/- 1.5% of set distance https://chesapeakemedicalsystems.com/wp-content/uploads/FDR-Visionary-Suite-Tube-head-1.jpg Quality Assurance Tests X-ray tube output X-ray tube output Why might this be important? https://umsystem.pressbooks.pub/app/uploads/sites/32/2022/08/Primary-and-Remnant-Radiation-1-234x300.jpg X-ray tube output Measure of radiation dose exiting tube Directly influences dose received by patient Directly influences resulting image quality https://umsystem.pressbooks.pub/app/uploads/sites/32/2022/08/Primary-and-Remnant-Radiation-1-234x300.jpg X-ray tube output - testing Place dose detector in centre of light field – collimate well Set appropriate source to detector distance Obtain measurements at range of parameters X-ray tube output - testing Test Meaning Repeatability Consistency of output for series of exposures at same settings Reproducibility Monitors effect of changes in parameters (kV, mA, s) on measured output X-ray tube output – testing - repeatability Series of exposures at same parameters (e.g. 80kV, 10mAs) Recorded measured Remedial level – mean doses – calculate mean +/- 10% value Compare individual Suspension level – mean measurements with +/- 20% mean value X-ray tube output – testing - reproducibility Series of exposures at range of kV, mA, s For each mA, calculate Remedial level – normalised dose - µGy / baseline +/- 20% mAs Compare average value Suspension level – baseline value baseline +/- 50% Repeat for each s setting X-ray tube output – testing - reproducibility For kV settings, trend of dose with kV should be same as at baseline Quality Assurance Tests Additional Level B tests Additional tests Test Frequency Exposure time 1-2 yearly Tube potential 1-2 yearly Half value layer Exposure time & tube potential Test at same time as Cover suitable range of tube output kV and time settings Exposure time remedial Tube potential remedial level: if t>100ms - +/- level: +/- 5% or 5kV, 10% of intended whichever is greater Exposure time Tube potential suspension level: if suspension level: +/- t>100ms - +/-20% of 10% or 10kV, whichever intended is greater Half value layer A measure of the X-ray beam energy Thickness of absorbing material needed to decrease beam intensity by half Usually use Aluminium as the absorber https://qcinradiography.weebly.com/uploads/4/5/9/0/45908103/1472969_orig.png Half value layer - testing Set fixed kV, mAs, distance Make series of exposures with increasing thicknesses of Al in the beam Identify half value thickness Remedial level: