Ch. 20 Screen film radiographic quality control Flashcards
Quality assurance deals with…
people
Who is mostly in control of QA?
the radiologist and the imaging services management
Quality control deals with…
instrumentation and equipment
What are the 10 steps for QA as set by the joint commission?
- Assign responsibility
- delineate scope of care
- identify aspects of care
- identify outcomes that affect the aspects of care
- establish limits of the scope of assessment
- collect and organize data
- evaluate care when outcomes are reached
- take action to improve care
- assess and document actions
- communicate information to organization-wide quality assurance programs
An acceptance QC program consists of 3 steps:
- acceptance testing
- routine performance monitoring
- maintenance
Who is principally responsible for QC?
the medical physicist
What is possible the most important patient protection characteristic of an imaging system?
filtration
What is the minimum total filtration needed in a system?
2.5 mm of Al equivalent
How is filtration measured?
by the HVL
How often are each tested and what is their tolerance?
Filtration, collimation, FSS, calibration of kVp, Exposure timer accuracy, exposure linearity, exposure reproducibility
Filtration: annually; >/=2.5mm Al Collimation: semiannually; +/- 2% SID FSS: Annually; +/- 50% kVP: Annually; +/- 10% Exp. timer: Annually; +/- 5% > 10ms Exp. linearity: Annually; +/- 10% Exp. reproducibility: Annually; +/- 5%
What type of collimators do most systems have?
PBL
What are so special about PBL collimators?
they automatically adjust to the size of the IR.
How is the spatial resolution of an imaging system determined?
Generally by the FSS of the tube.
3 tools are used for measurement of FSS…
the pinhole camera, the star pattern, and the slit camera
What is the standard of measure for FSS and why not the other 2?
The slit camera b/c it’s easy
The pinhole camera is too difficult to use and requires excessive exposure time and the star pattern is easy to use but has significant limitation s for FSS less than 0.3mm.
