ARRT Bone Density Exam Study Set – Questions
and 100% Correct Answers | Latest 2025/2026
Verified 100% Correct
A technologist should perform a precision study in order to calculate
_______________. - ANSWER -LSC (Least Significant Change)
A DXA scanner that uses a single detector and a pinhole collimator is a........ -
ANSWER -pencil beam scanner
Regarding Shewart Rules, the control limits are based on what percentage of the
average values? - ANSWER -1.5% (3 SD)
What is the sum of the data values divided by the number of values? - ANSWER -
mean
A DXA system that employs a rare earth filtered x-ray source uses what type of
detector? - ANSWER -pulse counting
The characteristic shapes of the vertebrae seen on the DXA image are primarily
based on the appearance of the ____________ elements. - ANSWER -posterior
Accuracy - ANSWER --ability to measure true value
-most important for diagnosis
-less important for serial monitoring
-affected by the technology
Cortical bone makes up what? - ANSWER -outer cover of bones
,What percentage of trabecular bone is found in the PA spine? - ANSWER -66%
the forearm, pelvis, and scapula all belong to which skeletal classification? -
ANSWER -appendicular
The WHO criteria for diagnosing osteoporosis was initially to apply to only........ -
ANSWER -postmenopausal Caucasian women
In order to do a compare analysis... - ANSWER --the patient must have a previous
scan done on the same anatomy
-you must retrieve the baseline study
-patient position must be consistent
How many degrees should you rotate the femur when positioning for a proximal
femur scan? - ANSWER -15-25 degrees
When should Z-scores be used to make a diagnosis instead of T-scores? -
ANSWER -males or females under age 20
What is the name of the isotope used in DPA? - ANSWER -Gadolinium-153
What bone parameter is measured in grams? - ANSWER -BMC
The region of the proximal femur lying on the border of the femoral neck and the
greater trochanter is termed the.............. - ANSWER -Ward's Area
What are the diagnosis guidelines for children? - ANSWER --z-scores are used
-"low for age" is used instead of "osteopenia"
-pediatric software is highly recommended
,What is the age range used with FRAX? - ANSWER -40-90 years
What is the number which the precision error is multiplied to determine the LSC
at 95% confidence level? - ANSWER -2.77
What skeletal site may be preferred for assessing early menopause following an
oophorectomy? - ANSWER -spine
An increase in the overall bone mass of a patient is closely related to an
accelerated rate of bone ___________ and a reduced amount of _______________.
- ANSWER -formation; resorption
What scan measures the most trabecular bone? - ANSWER -QCT of the spine
What are 2 types of exercise that are great for your bones? - ANSWER --weight
bearing
-weight resistence
What are the 4 classifications that apply to the heel? - ANSWER --appendicular
-peripheral
-predominantly trabecular
-weight bearing
What is the most accurate method to determine a patient's response to therapy for
osteoporosis? - ANSWER -Serial DXA measurements of the proximal femur and
spine
DXA results may be influenced by - ANSWER --body thickness
-degenerative changes
-fractures
, -scan speed/mode
Sunlight is the main source of vitamin _____ - ANSWER -D
All follow up DXA scans should be compared to the ________scan - ANSWER -
baseline
With long term use of steroids, what type of bone would be affected? - ANSWER
-Trabecular
If a patient has a history of a laminectomy, how would that affect the results? -
ANSWER -Decrease BMD
How many people are affected with low bone mass in the US? - ANSWER -54
million
The _____ is the only validated skeletal site for the clinical use of QUS in
osteoporosis. - ANSWER -heel
Standard Deviation (SD) - ANSWER -measure of the variability or the spread of
data around the mean
As _______ increases, the risk for a hip fracture increases independent of the
BMD - ANSWER -HAL (hip axis length)
What is the scanning pattern used with the pencil beam? - ANSWER -rectilinear
What does Sievert refer to? - ANSWER -effective dose
What is accuracy most important for? - ANSWER -diagnosis
*less important for serial monitoring
and 100% Correct Answers | Latest 2025/2026
Verified 100% Correct
A technologist should perform a precision study in order to calculate
_______________. - ANSWER -LSC (Least Significant Change)
A DXA scanner that uses a single detector and a pinhole collimator is a........ -
ANSWER -pencil beam scanner
Regarding Shewart Rules, the control limits are based on what percentage of the
average values? - ANSWER -1.5% (3 SD)
What is the sum of the data values divided by the number of values? - ANSWER -
mean
A DXA system that employs a rare earth filtered x-ray source uses what type of
detector? - ANSWER -pulse counting
The characteristic shapes of the vertebrae seen on the DXA image are primarily
based on the appearance of the ____________ elements. - ANSWER -posterior
Accuracy - ANSWER --ability to measure true value
-most important for diagnosis
-less important for serial monitoring
-affected by the technology
Cortical bone makes up what? - ANSWER -outer cover of bones
,What percentage of trabecular bone is found in the PA spine? - ANSWER -66%
the forearm, pelvis, and scapula all belong to which skeletal classification? -
ANSWER -appendicular
The WHO criteria for diagnosing osteoporosis was initially to apply to only........ -
ANSWER -postmenopausal Caucasian women
In order to do a compare analysis... - ANSWER --the patient must have a previous
scan done on the same anatomy
-you must retrieve the baseline study
-patient position must be consistent
How many degrees should you rotate the femur when positioning for a proximal
femur scan? - ANSWER -15-25 degrees
When should Z-scores be used to make a diagnosis instead of T-scores? -
ANSWER -males or females under age 20
What is the name of the isotope used in DPA? - ANSWER -Gadolinium-153
What bone parameter is measured in grams? - ANSWER -BMC
The region of the proximal femur lying on the border of the femoral neck and the
greater trochanter is termed the.............. - ANSWER -Ward's Area
What are the diagnosis guidelines for children? - ANSWER --z-scores are used
-"low for age" is used instead of "osteopenia"
-pediatric software is highly recommended
,What is the age range used with FRAX? - ANSWER -40-90 years
What is the number which the precision error is multiplied to determine the LSC
at 95% confidence level? - ANSWER -2.77
What skeletal site may be preferred for assessing early menopause following an
oophorectomy? - ANSWER -spine
An increase in the overall bone mass of a patient is closely related to an
accelerated rate of bone ___________ and a reduced amount of _______________.
- ANSWER -formation; resorption
What scan measures the most trabecular bone? - ANSWER -QCT of the spine
What are 2 types of exercise that are great for your bones? - ANSWER --weight
bearing
-weight resistence
What are the 4 classifications that apply to the heel? - ANSWER --appendicular
-peripheral
-predominantly trabecular
-weight bearing
What is the most accurate method to determine a patient's response to therapy for
osteoporosis? - ANSWER -Serial DXA measurements of the proximal femur and
spine
DXA results may be influenced by - ANSWER --body thickness
-degenerative changes
-fractures
, -scan speed/mode
Sunlight is the main source of vitamin _____ - ANSWER -D
All follow up DXA scans should be compared to the ________scan - ANSWER -
baseline
With long term use of steroids, what type of bone would be affected? - ANSWER
-Trabecular
If a patient has a history of a laminectomy, how would that affect the results? -
ANSWER -Decrease BMD
How many people are affected with low bone mass in the US? - ANSWER -54
million
The _____ is the only validated skeletal site for the clinical use of QUS in
osteoporosis. - ANSWER -heel
Standard Deviation (SD) - ANSWER -measure of the variability or the spread of
data around the mean
As _______ increases, the risk for a hip fracture increases independent of the
BMD - ANSWER -HAL (hip axis length)
What is the scanning pattern used with the pencil beam? - ANSWER -rectilinear
What does Sievert refer to? - ANSWER -effective dose
What is accuracy most important for? - ANSWER -diagnosis
*less important for serial monitoring
