Previous Exam Guides Flashcards
QA program monitors
ppl
QC program is for
film processors, CT scanners, XR tubes
most QC testing on rad equipment is done
annually
all general purpose rad units must have a min. of _____ mm Al filtration
2.5
filtration is measured w _______ measurements
HVL
focal spot size is measured w
pinhole/star/slit camera
it is acceptable to perform a ______ test instead of measuring the focal spot size
line pair
the measured kVp should be +/- ____ of the kVp indicated on the console
10%
what is the testing device used to measure cassette screen-film contact?
wire-mesh
comparing the mR output ay 50 mA @ 0.2 sec, 100 mA @ 0.1 sec, & 200 mA @ 0.05 sec is part of a test for _______
linearity
when a light in a viewbox is out, then
bulb must be replaced, all bulbs in viewboq must be replaced, all bulbs must match adjacent viewboxes
processor crossover racks should be cleaned out on a _______ basis
daily
processors should be monitored every day for
densitometric measurements, water/chem temps, & replenishment tank levels
an artifact can be
an object that is not part of the XRed anatomy, pt motion, improper grid, or warped cassette
a ________ is an example of an exposure artifact
foreign object
a static mark artifact is created during ______ of the film
handling
what sort of artifact is a guide-shoe mark?
processing artifact
the largest # of repeat exams is generally caused by ________ types of artifacts
exposure
misalignment of the processor turnaround assembly can cause?
guide-shoe marks
thin lines on the leading/trailing edge of a film are
guide-shoe marks
a bi-color chem stain on an XR
curtain effect, or dichroic stain
low humidity in the darkroom can cause
tree static
a streak of high optical density on the finished XR can be caused by
light leaks in the cassette/darkroom
when a QC test for exposure linearity is performed, adjacent mA stations must be w/in this amount of one another
10%
when a QC test for exposure reproducibility is performed, successive exposures must be w/in this amount of one another
5%
when QC test for collimator accuracy is performed, result must be w/in this amount
2% of SID
when a QC test for accuracy of kVp is performed, the result must be w/in _____ of the control panel setting
10%
the accuracy of collimation at a 72” SID must be
+/- 1.44”
unwanted markings on a XR are called
artifacts
small marks on XR about 3.1416” apart are called
pi lines
when insufficient light is produced, the img will be grainy, a condition known as
quantum noise
the aspect of a film-screen system that may be examined by conducting a wire mesh test is the
film-screen contact
what can cause img blur on the finished XR?
pt motion
which artifact occurs when the grid lines are II to the laser lines in a CR?
Moiré
a math process of assigning a digi value to a dead pixel based on recorded values of adjacent pixel is known as
interpolation
the effect or irregular pattern (variations in img brightness) can be minimized by
flat fielding
a software correction that is performed to equalize the response of ea pixel to a uniform XR beam is known as
flat fielding
what is a histogram?
a plot of the frequency of appearance of a given object char.’s; a graph of frequency of occurrence v digital value intervals
about 80% of breast cancer occurs in
ductal tissue
it is recommended that women obtain their 1st baseline mammo before the age of
40
a target of Mo or Rh is preferable in mammo bc it reduces the?
scatter
breast compression has the advantage of lowering
pt dose, motion blur, & superimposition
breast compression is used to ____ pt dose, and _____ focal spot blur
lower, reduce
breast compression increases
contrast & spatial res.
mammograms are taken w _______ cassettes
single screen
mammography currently uses ______ film
single-emulsion
screening mammo requires _____ view(s) of ea breast, whereas diagnostic mammo requires _______ views
2, 2+
the ________ is responsible for supervising QA
chief radiologist
the purpose of QA program is to maintain max ________ w min _________
quality mammos, pt dose
the avg glandular dose to mammo pt’s must be tested annually by the
medical physicist
the team of _________________ is responsible for mammo QC
mammographer, radiologist, & medical physicist
the ________ is responsible for selecting the medical physicist & mammographers responsible for QC
radiologist
when is the QC eval of the equipment performed?
once a year or when major components are replaced
the role of a medical physicist includes
performing annual performance evals of equipment, consult w mammographers concerning QC, & review QC records to check for compliance