Deck 39: Bone Densitometry

Question 1

All of the following are osteoporosis risk factors EXCEPT

A)gender.
B)cigarette smoking.
C)ethnicity.
D)salt intake.

Answer 1

salt intake.

Question 2

The likelihood of a bone fracture and bone integrity is best measured by

A)assessing the bone mineral density (BMD).
B)cortical thickness.
C)the ratio between compact bone and spongy bone.
D)basal metabolic rate (BMR).

Answer 2

assessing the bone mineral density (BMD).

Question 3

Fractures of the ______ have the highest degree of morbidity and mortality.

A)wrist
B)hip
C)spine
D)knee

Answer 3

hip

Question 4

The resorption of bone is carried out by the action of

A)osteocytes.
B)lacunae.
C)osteoblasts.
D)osteoclasts.

Question 5

Type II osteoporosis is distinguished from Type I in that

A)Type I is hormonal in nature.
B)Type II is age-related.
C)Type I is post-menopausal.
D)all of the above

Question 6

Quantitative ultrasound

A)commonly uses the forearm for analysis.
B)is as accurate as DXA scanning for assessing the degree of bone loss.
C)is economical and more convenient that DXA scanning.
D)measures the attenuation of sound energy and the thermal energy it creates in bone.

Question 7

A significant loss of bone mass and bone density results in the condition of

A)osteopetrosis.
B)osteochondritis dissecans.
C)osteoporosis.
D)osteoid osteoma.

Question 8

Primary osteoporosis

A)can be classified as Type I and Type II.
B)is often the result of hyperparathyroidism.
C)often results from metastatic bone disease.
D)can occur in persons taking gluticocorticoids.

Question 9

All of the following are related except one.Select the choice that is NOT RELATED to the others.

A)vertebral bodies
B)distal radius
C)greater trochanter
D)tarsals

Question 10

DXA scanning relies on the assessment of BMD for an individual and compares this value to

A)similar persons in the same age group.
B)persons with peak bone mass in their twenties.
C)persons with similar lifestyles and ethnicity.
D)the BMD value from early childhood.

Question 11

All of the following are true of SXA scanning EXCEPT:

A)It uses a radioactive source of iodine.
B)It was restricted to the forearm.
C)It employs an x-ray beam of discrete energy.
D)Its development followed SPA technology.

Question 12

General radiography is ineffective in measuring bone loss since as much as ______ of bone mass must be lost to be radiographically detected.

A)15%
B)30%
C)40%
D)60%

Question 13

All of the following are true of the bone remodeling process EXCEPT:

A)It is a balanced activity between the action of osteocytes and chondrocytes.
B)It is influenced by hormones.
C)Osteoclast activity in excess can result in a loss of bone mass.
D)Osteoblast activity equals osteoclast activity in a healthy individual.

Question 14

Eighty percent of human skeletal mass is made up of

A)cancellous bone.
B)cortical bone.
C)spongy bone.
D)trabecular bone.

Question 15

In healthy adults, peak bone mass occurs

A)following menopause.
B)at puberty.
C)in their twenties and mid-thirties.
D)at the onset of menarche.

Question 16

Persons with severe osteoporosis

A)show little risk of a fracture.
B)have a T-score of -2.5 or greater.
C)have a bony fracture from simple lifestyle activities.
D)both a and c

Question 17

DXA scanning

A)requires no radiation.
B)is expensive compared to CT scans.
C)measures sites that are prone to fracture.
D)can be a lengthy process if three sites are scanned.

Question 18

DXA scanning provides a statistical assessment of a person's T-score and Z-score.Both of these measures are similar except for the fact that the T-score is

A)calculated using a normative group with peak bone mass.
B)age-specific.
C)not recognized by the World Health Organization (WHO).
D)all of the above

Question 19

Dual energy x-ray absorptiometry (DXA)

A)uses radioactive gadolinium.
B)is performed on a CT scanner.
C)uses two discrete gamma photon energies.
D)is the current standard of care for osteoporosis detection.

Question 20

Osteopenia occurs with a T-score of

A)+1.9.
B)+2.5.
C)-2.0.
D)-2.7.

Question 21

Match the following choices with the correct statement as each relates to bone densitometry.
osteoporosis risk factor

A)fan-beam DXA
B)osteopenia
C)WHO
D)SPA
E)osteoblasts
F)osteoporosis
G)pencil-beam DXA
H)osteoclasts
I)NEXT
J)small stature

Question 22

Proper patient positioning for DXA scans of the hip includes

A)the femoral greater trochanter in profile.
B)clear visibility of the lesser trochanter.
C)foreshortening of the femoral neck to make it parallel to the long axis of the table.
D)external rotation of the feet.

Question 23

DXA scanning systems

A)are classified as fan beam or pencil beam.
B)may use a rare-earth filtered x-ray source.
C)may employ a synchronous, high frequency generator to switch between photon energies.
D)all of the above

Question 24

Quality control procedures with DXA systems

A)are done monthly.
B)utilize a standardized hip phantom for measurements.
C)are completed after each patient exam.
D)none of the above

Question 25

Match the following choices with the correct statement as each relates to bone densitometry.
bone-forming cells that can go dormant when not needed

A)fan-beam DXA
B)osteopenia
C)WHO
D)SPA
E)osteoblasts
F)osteoporosis
G)pencil-beam DXA
H)osteoclasts
I)NEXT
J)small stature

Question 26

The principle of DXA scanning relies upon the

A)attenuation of two discrete photon energy levels through soft tissue and bone.
B)measurement of scatter energy from the patient at two energy levels.
C)measurement of scatter photon energy subtracted from primary photon energy.
D)ratio of Bremsstrahlung and characteristic radiation production.

Question 27

A modern DXA scanning system consists of
1)workstation
2)x-ray tube
3)Bucky assembly
4)x-ray detector
5)tilting, radiolucent table
6)QC phantom
7)AEC system with three fields
8)positioning aides

A)1, 2, 5, 6, 7, and 8
B)1, 2, 3, 4, and 5
C)1, 2, 4, 6, and 8
D)1, 2, 3, 4, 5, and 7

Question 28

The BMD values of a DXA phantom

A)change yearly due to decay of the polymer resin of the phantom.
B)are stable and permit sharing phantoms between DXA systems.
C)never change.
D)are used to calculate the T-scores of patients.

Question 29

Match the following choices with the correct statement as each relates to bone densitometry.
established T-score and Z-score value benchmarks

A)fan-beam DXA
B)osteopenia
C)WHO
D)SPA
E)osteoblasts
F)osteoporosis
G)pencil-beam DXA
H)osteoclasts
I)NEXT
J)small stature

Question 30

The radiation dose during DXA studies

A)is less for fan-beam scanners.
B)is comparable to mammography.
C)permits easy compliance with ALARA principles.
D)requires lead protection in the walls of the exam room.

Question 31

Match the following choices with the correct statement as each relates to bone densitometry.
destroy bone

A)fan-beam DXA
B)osteopenia
C)WHO
D)SPA
E)osteoblasts
F)osteoporosis
G)pencil-beam DXA
H)osteoclasts
I)NEXT
J)small stature

Question 32

Match the following choices with the correct statement as each relates to bone densitometry.
lowest dose type of DXA technology

A)fan-beam DXA
B)osteopenia
C)WHO
D)SPA
E)osteoblasts
F)osteoporosis
G)pencil-beam DXA
H)osteoclasts
I)NEXT
J)small stature

Question 33

Match the following choices with the correct statement as each relates to bone densitometry.
uses multiple detector elements

A)fan-beam DXA
B)osteopenia
C)WHO
D)SPA
E)osteoblasts
F)osteoporosis
G)pencil-beam DXA
H)osteoclasts
I)NEXT
J)small stature

Question 34

DXA scanning of the forearm

A)is preferred for suspected hyperparathyroidism.
B)scans the non-dominant forearm.
C)includes the proximal row of carpal bones.
D)all of the above

Question 35

DXA scans of the spine

A)are done with the patient supine and with legs fully extended.
B)are considered more reliable than those of the hip or forearm.
C)include the lumbar vertebrae L₂- L₄.
D)include all lumbar vertebrae regardless of T score between the individual vertebrae.

Question 36

Match the following choices with the correct statement as each relates to bone densitometry.
T-score of -2.2

A)fan-beam DXA
B)osteopenia
C)WHO
D)SPA
E)osteoblasts
F)osteoporosis
G)pencil-beam DXA
H)osteoclasts
I)NEXT
J)small stature

Question 37

The most commonly measured anatomical structures in DXA scanning are the

A)wrist and shoulder.
B)ankle and knee.
C)pelvis and spine.
D)hip and spine.

Question 38

Match the following choices with the correct statement as each relates to bone densitometry.
uses radioactive Iodine as a photon source

A)fan-beam DXA
B)osteopenia
C)WHO
D)SPA
E)osteoblasts
F)osteoporosis
G)pencil-beam DXA
H)osteoclasts
I)NEXT
J)small stature