8 - Quality Assurance Flashcards
what is quality assurance? (WHO definition)
- an organised effort by staff to ensure that the diagnostic images produced are of sufficiently high quality to consistently provide adequate diagnostic information at the lowest possible cost and least possible exposure to patient
quality assurance is implemented due to the inevitability of human error. state some reasons why mistakes occur.
- inattention to detail
- equipment failure
- human error
- lack of training
human error is impossible to completely eliminate, state a few methods to reduce the chance of error
- introduce simple systems to follow (SOPs)
- improve working environment
- encourage reporting (without blame)
legislations to enforce quality assurance? who does each one protect?
IR(ME)R 2000: protects the patient
IRMER 99: protects staff and public but also deals with patient protection in relation to equipment
IR(ME)R 2000:
employer is responsible for?
- employer shall establish QA programmes for standard operating procedures
- employer shall ensure that every practitioner and operator undertakes CPD
components of a quality assurance programme?
- named person
- details of procedure involved
- frequency procedures carried out
- frequency records will be audited
- all above must be put in writing
what do we look at in a quality assurance programme?
- image quality
- x-ray equipment
- processing (film and digital)
- working procedures
- training
- audit
QA - image quality: how do we ensure high quality images?
audit the images produced:
- image quality rating system
- film reject analysis
QA - image quality: image quality rating system - how does it work?
- assess all images produced
- grade films by quality: either 1, 2, or 3
- collate results - analyze monthly, quarterly or at least every 6 months
- feedback results to staff
QA - image quality: image quality rating system - describe grade 1
no errors of patient preparation, exposure, positioning, processing or film handling
QA - image quality: image quality rating system - describe grade 2
diagnostically acceptable; some errors in preparation, exposure, positioning, processing or handling which do not detract from the diagnostic utility of the radiograph
QA - image quality: image quality rating system - describe grade 3
unacceptable - errors of patient preparation, exposure, processing and/or handling which render radiograph diagnostically unacceptable
QA - image quality: image quality rating system - target of films graded 1-3?
number of films:
grade 1 > 70%
grade 2 <20%
grade 3 <10%
QA - image quality: film reject analysis
- when do assess these films?
- what to categorise?
- what to do after?
- end of each month
- categorise in terms of faults: exposure, positioning, processing etc
- act and repeat every month and compare results
describe the IQRS audit cycle
- Grade (1, 2, 3)
- Result - look for ways to improve
- Feedback
- Assess (evaluate images)
QA - x-ray equipment: what are the requirements for equipment?
- equipment inventory must be kept
- all equipment must be tested regularly to check that it is working satisfactorily
- preferably annually, but minimum of every 3 years
- checks must include representative patient doses
- routine maintenance - annually
QA - processing: what to assess?
- storage and stock rotation
- monitoring of processor performance
- processor maintenance
- monitoring performance of digital system
film storage: digital - PSP
what kind of conditions?
protected from?
what to do if not used for more than 24hours?
- cool and not too humid
- avoid direct sunlight and UV
- preferably in light protection and cross infection barrier envelope
- if not used for more than 24 hours after plate erased, it should be erase again
sensitometry:
- how does image change when developer is exhausted?
- simple step-wedge: how does image look like when it is radiographed?
- the image becomes pale
- the image will show “steps” of blackening from pale grey to dark grey/black
sensitometry: what to look out for in step-wedge to check for developer exhaustion?
- place step-wedge on dental film packet and expose
- process film in fresh chemistry
- check films for obvious changes in densities e.g. drop of one step from standard reference film
step-wedge film v.s. pre-exposed film?
- price
step-wedge is cheaper, uses intra-oral film. pre-exposed expensive but easy to use - discrepancies in production
step-wedge film: operator variables can cause discrepancies in production. pre-exposed does not have discrepancies in production. every film should be the same - results dependent on viewer?
step-wedge film results are dependent on the person viewing. pre-exposed results not dependent on viewer
common problems during film processing?
damage could be due to:
- poor handling; bends, crimps
- insufficient training - overlapping of image
- light - fogging
causes of fogged film?
- light entering darkroom
- safelight: filter unsuitable for film or too close to work surface
- test
describe the coin test
- open intra-oral xray packet and remove the film. do this while hands are inside glove box or in darkroom under safelight conditions
- place a coin on the film
- leave coin on film for a specified amount of time (5 mins or average working time)
- remove coin and process film
- check the processed film for light fogging
- repeat test for every different type and speed of film used in practice
- act on findings
digital receptors - how often to check:
solid state sensors?
PSP?
what to check for computer monitors?
solid state sensors: visual check for physical damage weekly and radiographic monthly
PSP: visual check weekly and radiograph monthly
computer monitors: check settings, resolution
QA - working procedures: IR(ME)R 2000 states?
- employer must provide written procedures
- for actions that indirectly affect radiation safety or diagnostic quality e.g. correct preparation and use of processing chemicals
QA - training
what is considered suitably qualified?
“adequately trained”
- dentists, hygienists with a cert in dental radiography, dental nurses with post-qualification cert in dental radiography
- all persons indirectly involved in production of radiographs should have suitable training
QA - audit which IR(ME)R procedures are subject to audit?
all procedures; e.g. patient identification, clinical evaluation of images, justification of radiographic examination, image quality
