DXA STUDY GUIDE EXAM QUESTIONS AND ANSWERS
Risk factors for osteoporosis - CORRECT ANSWER✅✅female, age, skinny, smoking, alcoholics, steroids,
menopause, malnutrition, family hx, Asians/whites
All of the following are osteoporosis risk factors EXCEPT
a. gender.
b. cigarette smoking
c. ethnicity.
d. salt intake. - CORRECT ANSWER✅✅d. salt intake.
Dual energy x-ray absorptiometry (DXA) uses two discrete gamma photon energies. T/F? - CORRECT
ANSWER✅✅False (DPA did)
Eighty percent of human skeletal mass is made up of
a. cancellous bone
b. cortical bone
c. spongy bone
d. trabecular bone - CORRECT ANSWER✅✅b. cortical bone
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. - CORRECT ANSWER✅✅persons with peak bone mass in their
20's (T-score)
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 - CORRECT ANSWER✅✅d. all of the above
Osteopenia occurs with a T-score of
a. +1.9.
b. +2.5.
c. -2.0.
d. -2.7. - CORRECT ANSWER✅✅c. -2.0.
DXA scanning uses a radioactive source of iodine. - CORRECT ANSWER✅✅False (SPA did)
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. - CORRECT ANSWER✅✅a. It uses a radioactive source of
iodine.
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. - CORRECT ANSWER✅✅a.
attenuation of two discrete photon energy levels through soft tissue and bone.
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.
Risk factors for osteoporosis - CORRECT ANSWER✅✅female, age, skinny, smoking, alcoholics, steroids,
menopause, malnutrition, family hx, Asians/whites
All of the following are osteoporosis risk factors EXCEPT
a. gender.
b. cigarette smoking
c. ethnicity.
d. salt intake. - CORRECT ANSWER✅✅d. salt intake.
Dual energy x-ray absorptiometry (DXA) uses two discrete gamma photon energies. T/F? - CORRECT
ANSWER✅✅False (DPA did)
Eighty percent of human skeletal mass is made up of
a. cancellous bone
b. cortical bone
c. spongy bone
d. trabecular bone - CORRECT ANSWER✅✅b. cortical bone
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. - CORRECT ANSWER✅✅persons with peak bone mass in their
20's (T-score)
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 - CORRECT ANSWER✅✅d. all of the above
Osteopenia occurs with a T-score of
a. +1.9.
b. +2.5.
c. -2.0.
d. -2.7. - CORRECT ANSWER✅✅c. -2.0.
DXA scanning uses a radioactive source of iodine. - CORRECT ANSWER✅✅False (SPA did)
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. - CORRECT ANSWER✅✅a. It uses a radioactive source of
iodine.
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. - CORRECT ANSWER✅✅a.
attenuation of two discrete photon energy levels through soft tissue and bone.
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.
