evaluation of image quality Flashcards
2 fixed anatomical borders
medial, superior
2 mobile anatomical borders
lateral, inferior
positioning requirements for CC view
posterior tissue, 30-40% muscle, PNL w/in 1cm of MLO, NIP
positioning requirements for MLO view
posterior tissue from axilla to IMF, convex muscle shape down to PNL, out and up lift, NIP
lateral-posterior and superior tissues potentially not well imaged on the ____ view
cc
medial-posterior tissue potentially not well imaged on the ____ view
mlo
3 top reasons for failure on the CC view
PNL not within 1 cm of MLO view- short PNL = poor visualization of the posterior tissue
excessive exaggeration
skin folds or artifacts
failure on the MLO view
poor visualization of posterior tissue,
improper demonstration of the pectoralis muscle,
inadequate amount of pectoralis muscle,
drooping tissue,
skin folds,
breast positioned too high on IR,
inadequate IMF,
inadequate anterior breast compression
poor separation of glandular tissue, unequal exposure of tissue, allows for motion
inadequate compression
breast looks uniform in thickness, reduces dose, reduces unsharpness
optimal compression
motion seen on 2D images- 3 fixes:
increase KVP= decrease in exposure time
hold breath
patient sit down
compression min/max suggestions
pounds
newtons
decanewtons
15-27 LBS
70-120 N
7-12 DaN
which portion should be checked for tautness
anterior
the most common problem in mammography between under/over exposure- according to 1999 ACR manual
underexposure
results in decreased radiographic contrast and when its only present in the densest part of the breast it will obscure lesions and micro-calcifications; image looks “washed out”
underexposure
in mammo you want ___ contrast and ____ dose; ____ contrast allows us to see subtle differences
high
low
high
7 common causes for poor contrast
underexposure
image run under wrong label
inadequate compression
failure to use grid
excessive kvp
improper positioning
implant/hardware
inadequate compression =
beam hardening
ability of the mammo system to capture fine detail in an images
sharpness
1 cause of image unsharpness
patient motion
5 causes of image unsharpness
patient motion
inadequate compression
increase to focal spot size
increase OID
decrease to SID
decreases the ability of the radiologist to recognize tiny structures like calcifications and low contrast structures
noise
another name for noise
radiographic mottle
anything we can see on a mammo image that does not reflect actual breast tissue
artifacts
3 types of artifacts
hardware, software, patient related
hardware related artifacts
field inhomogeneity
detector associated
grid lines
4 detector associated artifacts
ghosting
gouging
horizontal lines
collimator misalignment
2 software related artifacts
breast within a breast
loss of edge
3 patient related artifacts
patient motion
edge of compression paddle
deodorant/powder
8 MQSA labeling requirements
patient name
patient MRN
exam date
view name
facility name/location
tech ID
cassette ID
unit ID
ACR grades your images on 8 categories
positioning
compression
exposure
contrast
sharpness
noise
artifacts
labeling
MQSA minimum is __ megapixel monitors for review workstation
5
priors are retrieved in one of 3 ways
manually
prefetch
autofetch
what is “computer language”
health level seven HL7
manages the information related to health care and manages data from all departments
HIS hospital information system
software that helps manage the rad dept and its specific modalities
RIS radiology information system
a standard that medical professionals use to share radiology images and data between different system made by different manufacturers
digital imaging and communications in medicine DICOM
medical imaging technology used in healthcare organizations to securely store, retrieve, and transmit electronic images and reports from multiple modalities; replacement for hard copies
picture archiving and communication system PACS
offsite server; can be used as a backup to traditional PACS; secure connection to provide access to images and related data; same as traditional PACS, except authorized users can access the images anytime anywhere as long as they have an internet connection; images approx. available for 30 days
cloud storage-cloud PACS
a digital version of a paper chart that contains pts medical history from one practice. has the ability to share this information across other healthcare organizations
electronic medical/health record EMR/EHR
allows data to be stored in a smaller package. requires less space and less money to store. allows images to move faster over the network. mammos has special rules about compression. lossy compression. lossless compression.
image/data compression
greater degree of compression; requires less space; up to 30:1 ratio; some data loss upon retrieval; not allowed for FFDM
data compression-lossy compression
2:1 ratio; only format for FFDM. not insignificant in terms of saved space; not data loss
data compression-lossless compression
2 major roles of CAD computer aided detection
detection
classification
goal is to improve mammo sensitivity by increasing detection in breast density
computer aided detection CAD-classification
directed toward finding microcalcifications and masses
computer aided detection CAD-detection
