Deck 33: Bone Densitometry

Question 1

Risk factors for falling and causing fractures are:
1)antidepressants.
2)impaired muscle strength.
3)environmental hazards.

A) 1 and 2
B) 1 and 3
C) 2 and 3
D) 1, 2, and 3

Answer 1

1, 2, and 3

Question 2

Precision relates to the ability of the system to:

A) measure the true value of an object.
B) reproduce the same results in repeat measurements of the same object.
C) reflect the bone measurement by the scanner software.
D) measure the variability of the spread of data values around the mean.

Answer 2

reproduce the same results in repeat measurements of the same object.

Question 3

The purpose of bone densitometry is to:

A) establish the diagnosis of osteoporosis.
B) assess the response to osteoporosis therapy.
C) measure bone mineral density.
D) do all of the above.

Answer 3

do all of the above.

Question 4

The T-score is used to assess:

A) the reference population.
B) fracture risk for the patient.
C) if the measured BMD is reasonable.
D) patient age and bone loss.

Question 5

Bone-destroying cells are called:

A) osteoblasts.
B) osteoclasts.
C) cancellous.
D) cortical.

Question 6

The most common osteoporotic fracture is found in the:

A) hips.
B) femurs.
C) vertebrae.
D) ankles.

Question 7

Radiation dose for DXA scans is:

A) twice as much as for a diagnostic lumbar x-ray.
B) half as much as for a lumbar CT examination.
C) similar to natural background radiation.
D) similar to a diagnostic hand x-ray.

Question 8

DXA calculations are based on:

A) body position and bone density.
B) bone density only.
C) soft tissue only.
D) soft tissue and bone.

Question 9

A BMD measurement from a patient is most useful when it can be compared statistically to:

A) the same patient age population.
B) a population living in the same area.
C) multiple scans on the same patient.
D) an appropriate sex-matched reference population.

Question 10

Which vertebral region(s) is (are) analyzed during a DXA scan?

A) T12
B) T7 to L1
C) L1 to L5
D) L4 to S2

Question 11

Which of the following is not a risk factor for osteoporosis?

A) Daily physical activity
B) Alcohol consumption
C) Low body weight
D) Low calcium intake

Question 12

The Z-score is used to determine:

A) the reference population.
B) fracture risk for the patient.
C) if the measured BMD is reasonable.
D) patient age and bone loss.

Question 13

What is the chief benefit of using a high and low x-ray energy source with a DXA system?

A) Reduces patient dose significantly
B) Reduces wear and tear on the x-ray tube to change energies
C) Demonstrates attenuation difference between bone and soft tissue
D) Reduces post-processing time of bone for the digital image

Question 14

Accuracy in bone densitometry relates to the ability of the system to:

A) measure the true value of an object.
B) reproduce the same results in repeat measurements of the same object.
C) reflect the bone measurement by the scanner software.
D) measure the variability of the spread of data values around the mean.

Question 15

Peak bone mass is reached at about age _____ years.

A) 10 to 20
B) 20 to 30
C) 30 to 40
D) 40 to 50

Question 16

When obtaining patient history for a bone density exam the technologist should obtain the patient's:
1)history of fractures.
2)standing height and weight.
3)insurance information.

A) 1 and 2
B) 1 and 3
C) 2 and 3
D) 1, 2, and 3

Question 17

Patient positioning should be exactly the same for all scans because:

A) the images need to look the same over time.
B) the results will be more precise, reflecting a true biologic change.
C) that will allow scans from different manufacturers to be comparable.
D) radiologists want the same positioning to read the images.

Question 18

The measurement of bone density uses two different beam energies, allowing the separation of soft tissue and bone due to:

A) filtration differences in the beam.
B) mass attenuation coefficient differences.
C) BMD population calculations.
D) the two-dimensional area.