ARRT BONE DENSITY EXAM STUDY SET

ARRT BONE DENSITY EXAM STUDY SET

COMPLETE ANSWERS 100% CORRECT (LATEST 2024 / 2025 )

1. Cancellous bone is also known as ?: Trabecular bone

• How would you start labeling the vertebral bodies on a PA lumbar scan?-

: Start at L4 and count/label up

• With changes in rotation of the femoral neck, what happens?: Increases the BMD
• If daily QC fails, what should be your first step of action?: -repeat the scan

-if scan fails again, then call for help

• Although the technology is similar with all of the DXA units, the BMD results are

different because..........:

-different calibration standards

-algorithms to calculate BMD

-differences in the ROI

-different databases

• The primary mechanism of action of antiresorptive therapies is the direct interaction with

the : osteoclasts

• Which site is preferred for determination of fracture prediction?: proximal femur

8. What is one disease not associated with low BMD?: osteopetrosis

9. DXA results may be influenced by.........:

-body thickness

-degenerative changes

-fractures

-scan mode 1 / 4

10. A great forearm scan should include.......: -forearm centered

-forearm straight

-free of artifacts

• Phantoms that mimic the shape and size of a skeletal region are called

.: anthromomorphic phantoms

12. What is the formula used to calculate BMD?: BMD = BMC/Area

13. How often should you perform the QA on the DXA unit?: everyday you scan

• Radiogammetry is the measurement of bones using skeletal x-rays/radiographs. Which

site was often used?: metacarpals

• With voltage switching units, what type of calibration is used?: continuous internal

calibration--wheel or drum

• For low energies, the most common process of absorption is the

effect.: photoelectric

• What are some comparisons to the amount of effective dose given during a central DXA

scan?: -less than a day of background radiation

-less than a round trip from Boston to LA

-one-tenth of a chest xray

• Why is the non-dominant arm used in bone densitometry?: reference values reflect non-

dominant arm measurements

• When measuring the proximal femur, how should the neck ROI be placed?-

: the neck ROI should be perpendicular to the femoral neck

• What is the bone edge detection methodology?: it tests the machines ability to distinguish

bone from soft tissue

• What are the two most common methods for shifting the energies in DXA units?: -energy

shifting

-k-edge filters 2 / 4

• Why do you use the hip positioner during scanning of the proximal femur?-

: to place the femoral neck parallel to the tabletop

• Bisphosphonates prevent bone loss by....: reducing the activity of the osteo- clasts
• If a patient has a history of hyperparathyroidism, what would the preferred site be for

evaluation?: 33% or 1/3 of the forearm

25. What is important for serial monitoring?: precision

• What pharmaceutical may be suggested for a woman with a high risk of breast cancer and

elevated lipids?: Evista (Raloxifene)

27. What year was the Bone Mass Measurement Act proposed?: 1997

• What type of osteoporosis is a result of menopause?: Primary Osteoporosis Type 1

29. What classes of cells are involved in bone remodeling?: -osteoclasts

-osteoblasts

-osteocytes

• What therapy mimics the effects of estrogen on bone and has antiestro- genic effects in

other tissue?: Raloxifene

• According to the WHO criteria, what is the diagnosis of osteoporosis based on the

measurement of bone density?: 2.5 SD or more below the young adult peak bone density

32. What is the gold standard technique for measuring bone density?: DXA

33. Cancellous bone is also know as?: Trabecular Bone

• What is the anatomical landmark on the proximal femur that gives the

best visual indication of the degree of rotation of the proximal femur?: Lesser Trochanter

• Which lumbar vertebra is described as having a characteristic shape of an X or and H on

a DXA PA spine scan?: L4

36. Is Forteo a bisphosphonate?: NO

37. Quantitative Computated Tomography (QCT): -measurements are volumetric

-trabecular bone can be isolated from cortical bone

-accuracy may be affected by marrow fat 3 / 4

Peripheral BMD measurements are advocated for ?:

Screening

38. What is the most important clinical consequence of osteoporosis?: Fracture

• What is the name of the tool that integrates clinical information in a quantitative manner

to predict a 10-year probability of major osteoporotic fracture for both men and women?: FRAX

• What is the major source of precision error in clinical practice?: Technologist

41. What is the percentage of trabecular bone in the skeleton?: 20 %

• The forearm is not used to monitor the effects of therapy for osteoporosis because.......: rate

of change in BMD is too slow

43. What site is mostly composed of cortical bone?: Proximal forearm

• What are the advantages of QUS over x-ray methodologies for BMD mea- surement?: -

ultrasound is comparatively inexpensive

-patients are not subjected to ionizing radiation

-ultrasound exams are quick to perform

45. What is the name of the isotope that was used in SPA?: Iodine-125

• What is the texture index that evaluates the pixel gray-level variations in lumber spine

DXA images?: TBS (Trabecular Bone Score)

47. When does type 2 primary osteoporosis generally occur?: after age 70

• What technique used images of the hand and an aluminum wedge?: RA (Radiograhic

Absorptiometry)

49. New bone is formed by the ?: osteoblasts

• In both men and women, bone mass increases until approximately what age?: 30 years
• What must be performed in order to compare studies when a new machine is bought?:

cross-calibration

• Which acronym best describes the least amount of BMD change that can be statistically

significant?: LSC

53. What are the 2 types of bone?: -cortical

• / 4