©JUSTTRACY EXAM SOLUTIONS
21/11/202410:55AM
Bone Mineral Densitometry Modified
Exam Questions And Responses
What BMD is - answers✔✔exam that measures the amount of bone mineral calcium
hydroxyapatite per unit volume of bone
How osteoporosis is described - answers✔✔Reduced volume of bone minerals.
Volume of calium hydroxypatite is 2.5 or more SD *below* the young gender match with
peak bone mass (T-score)
osteoperotic patients - answers✔✔Have a 2x increased fracture risk.
Address demineralization process with medications such as Premarin and Fosamax
Normal T-score - answers✔✔equal or greater than -1
Ultrasound and CT - answers✔✔Other modalities used to visually quantify BMD
Lumbar spine, hip, and forearm - answers✔✔Most common body areas used to measure bmd
Central skeleton - answers✔✔Includes:
vertebral column
ribs and sternum
pelvis
proximal femur
Peripheral Skeleton - answers✔✔Includes:
upper extremities
lower extremities (not including proximal femur)
, ©JUSTTRACY EXAM SOLUTIONS
21/11/202410:55AM
Central BMD devices - answers✔✔Designed to measure bone density of spine and hip
(capable of measuring forearm and body id necessary)
Common modalities: dual-energy absorptiometry (DXA) and quantitative computed
tomography (QCT)
Central DXA - answers✔✔Considered most current and accepted modality.
Provides excellent repoducibility
Widely used in epidemiological studies as well as pharmaceutical trials. (have successfullly
related DXA measurement of bmd to fracture risk)
Peripheral Devices - answers✔✔Designed to measure bone density in wrist, heel, finger, and
other extremities
Use all possible modalities:
Peripheral DXA(pDXA) - measures BMD forearm, heel or finger
Peripheral QCT(pQCT) - provides CT volumetric measurement of forearm
Quantitative ultrasound(QUS) -
measures the speed of sound through bone
DEXA operations - answers✔✔Same systems as x-rays: tube, collimator, and x-ray detector
Same radiographice factorsapply
DEXA collimation - answers✔✔Pencil beam:
-no longer being manufactured, but still commonly seen
- include a collimated x-ray beam and a single detector that move in sync
-scanning occurs at a point
Fan beam (array scanning):
-scan line by line
-wide angle fan beam orientated towards long axis of body
-narrow angle beam parallel to long axis of the body
-significantly shorter scan time, decreased image resolution and higher radiation doses
21/11/202410:55AM
Bone Mineral Densitometry Modified
Exam Questions And Responses
What BMD is - answers✔✔exam that measures the amount of bone mineral calcium
hydroxyapatite per unit volume of bone
How osteoporosis is described - answers✔✔Reduced volume of bone minerals.
Volume of calium hydroxypatite is 2.5 or more SD *below* the young gender match with
peak bone mass (T-score)
osteoperotic patients - answers✔✔Have a 2x increased fracture risk.
Address demineralization process with medications such as Premarin and Fosamax
Normal T-score - answers✔✔equal or greater than -1
Ultrasound and CT - answers✔✔Other modalities used to visually quantify BMD
Lumbar spine, hip, and forearm - answers✔✔Most common body areas used to measure bmd
Central skeleton - answers✔✔Includes:
vertebral column
ribs and sternum
pelvis
proximal femur
Peripheral Skeleton - answers✔✔Includes:
upper extremities
lower extremities (not including proximal femur)
, ©JUSTTRACY EXAM SOLUTIONS
21/11/202410:55AM
Central BMD devices - answers✔✔Designed to measure bone density of spine and hip
(capable of measuring forearm and body id necessary)
Common modalities: dual-energy absorptiometry (DXA) and quantitative computed
tomography (QCT)
Central DXA - answers✔✔Considered most current and accepted modality.
Provides excellent repoducibility
Widely used in epidemiological studies as well as pharmaceutical trials. (have successfullly
related DXA measurement of bmd to fracture risk)
Peripheral Devices - answers✔✔Designed to measure bone density in wrist, heel, finger, and
other extremities
Use all possible modalities:
Peripheral DXA(pDXA) - measures BMD forearm, heel or finger
Peripheral QCT(pQCT) - provides CT volumetric measurement of forearm
Quantitative ultrasound(QUS) -
measures the speed of sound through bone
DEXA operations - answers✔✔Same systems as x-rays: tube, collimator, and x-ray detector
Same radiographice factorsapply
DEXA collimation - answers✔✔Pencil beam:
-no longer being manufactured, but still commonly seen
- include a collimated x-ray beam and a single detector that move in sync
-scanning occurs at a point
Fan beam (array scanning):
-scan line by line
-wide angle fan beam orientated towards long axis of body
-narrow angle beam parallel to long axis of the body
-significantly shorter scan time, decreased image resolution and higher radiation doses
