DEXA EXAM REPORTED QUESTIONS
WITH CORRECT DETAILED
ANSWERS
DXA of the non-dominant forearm may be useful when:
1. DXA of the spine or hip cannot be performed or accurately interpreted
2. Very obese individuals exceed the weight limit of the DXA table
3. An individual has hperparathyroidism - Answer-1,2,3
What would not result in the evaluation of the bone mineral density of the UD (ultra
distal) radius with the use of DXA? - Answer-Scanning the non-dominant forearm
When using DXA to evaluate hyperparathyroidism, the preferred scan site is the____. -
Answer-Wrist
The measurement that must be obtained prior to performing a 33% radius DXA of the
forearm is the length of the_____. - Answer-Ulnar from the styloid process to the
olecranon
80% of the entire skeleton is comprised of _____. - Answer-Cortical bone tissue
When positioning for a DXA hip scan, the anatomical landmark that can be palpated on
the lateral portion of the femur is the____. - Answer-Greater trochanter
True or False. BMD measurements with DXA are two dimensional or areal
measurements, whereas QCT measurements are three dimensional or volumetric. -
Answer-True
True or False. Area is calculated by multiplying the height by the weight. - Answer-False
The area of the forearm that has the least percentage of trabecular bone is the______. -
Answer-33% radius or ulna
The area of the forearm that has the highest percentage of cortical bone is the____. -
Answer-33% radius or ulna
The posterior elements of L1, L2, and L3 have ____or____shaped appearance -
Answer-U, Y
,True or false. If the femoral neck is not parallel to the plane of the scan table, the xray
beam enters the neck at an angle that is greater or lesser than 90 degrees. - Answer-
True
Improper rotation of the proximal femur results in____. - Answer-A shortening of the
length of the neck of the femur and an increase in the mineral content in the path of the
beam equaling an increase in BMD.
The 5- or 8- mm sites located in the distal forearm are located________. - Answer-On
either bone at the point where the separation distance between the radius and ulna is 5-
or 8- respectively
A basic computer system includes:
1. Computer tower
2. Monitor
3. Keyboard
4. Mouse - Answer-1,2,3,&4
True or False. Excessive internal rotation of the proximal femur will result in the total
disappearance of the lesser trochanter. - Answer-True
BMC increases accordingly from ____to____. - Answer-L1 to L4
True or False. The BMD of 3 -4 continuous vertebrae is preferred for the measurement
in DXA over the BMD of 2 vertebrae averages. - Answer-True
If the actual value for the z-score were 2 standard deviations above the average, the z-
score would be____. - Answer-+2
True or False. A plus or minus sign is placed in the front of the z-score value to indicate
whether the value lies above or below the average. - Answer-True
The average value of the T-score is assigned the value of 50. If the actual value were 1
standard deviation above the average, the T score would be____. - Answer-60
The average value of the T-score is assigned the value of 50. If the actual value were 2
standard deviations below the average, the T-score would be_______. - Answer-30
What 2 factors have the greatest effect on the failure to achieve an average peak bone
density?
1. Dietary calcium deficiency
2. Lack of exercise.
3. Early menarche. - Answer-1&2
BMD based diagnostic classification should not be made:
1. If only one single vertebra can be utilized.
, 2. If only two vertebrae can be utilized.
3. If only three vertebrae can be utilized. - Answer-1
Anatomically abnormal vertebrae may be excluded from analysis if:
1. The vertebra appears clearly abnormal.
2. There is more than a 1.0 T-score difference between the vertebra in question and
adjacent vertebrae.
3. There is more than a -2.0 T-score difference between the vertebra in question and
adjacent vertebrae. - Answer-1&2
True or False. The term osteopenia means low bone mass or low bone density. -
Answer-True
The main functions of the bone are mechanical, protective and _____. - Answer-
Supportive
The strength of bone is determined by_______. - Answer-Bone density
The percentage of trabecular bone in the skeletal system is___. - Answer-20%
Which of the following bone density techniques delivers the largest amount of radiation?
The unit of measure that is used with QCT (quantitative computed tomography) is_. -
Answer-mg/cm3
The DXA system that employs a rare earth filtered x-ray source utilizes a ____detector.
- Answer-Pulse counting
When performing an x-ray of the forearm in the AP projection, the placement of the
hand should be in _____. - Answer-Supination
Z-scores in BMD measurements are relative percent values for ____________. -
Answer-Age matched normal controls
DPA is a method that uses_______. - Answer-One isotope with two photon emissions
What is the main purpose of bone densitometry? - Answer-Diagnosing osteoporosis by
detecting low bone mass before fractures occur.
What disease is characterized by hypersensitivity to gluten? - Answer-Adult sprue
Two dimensional representation of a three dimensional object. - Answer-Area
(projectional) technique
The hormone secreted by the thyroid that decreases the osteoclasts activity and
increases the osteoblasts activity is? - Answer-Calcitonin
WITH CORRECT DETAILED
ANSWERS
DXA of the non-dominant forearm may be useful when:
1. DXA of the spine or hip cannot be performed or accurately interpreted
2. Very obese individuals exceed the weight limit of the DXA table
3. An individual has hperparathyroidism - Answer-1,2,3
What would not result in the evaluation of the bone mineral density of the UD (ultra
distal) radius with the use of DXA? - Answer-Scanning the non-dominant forearm
When using DXA to evaluate hyperparathyroidism, the preferred scan site is the____. -
Answer-Wrist
The measurement that must be obtained prior to performing a 33% radius DXA of the
forearm is the length of the_____. - Answer-Ulnar from the styloid process to the
olecranon
80% of the entire skeleton is comprised of _____. - Answer-Cortical bone tissue
When positioning for a DXA hip scan, the anatomical landmark that can be palpated on
the lateral portion of the femur is the____. - Answer-Greater trochanter
True or False. BMD measurements with DXA are two dimensional or areal
measurements, whereas QCT measurements are three dimensional or volumetric. -
Answer-True
True or False. Area is calculated by multiplying the height by the weight. - Answer-False
The area of the forearm that has the least percentage of trabecular bone is the______. -
Answer-33% radius or ulna
The area of the forearm that has the highest percentage of cortical bone is the____. -
Answer-33% radius or ulna
The posterior elements of L1, L2, and L3 have ____or____shaped appearance -
Answer-U, Y
,True or false. If the femoral neck is not parallel to the plane of the scan table, the xray
beam enters the neck at an angle that is greater or lesser than 90 degrees. - Answer-
True
Improper rotation of the proximal femur results in____. - Answer-A shortening of the
length of the neck of the femur and an increase in the mineral content in the path of the
beam equaling an increase in BMD.
The 5- or 8- mm sites located in the distal forearm are located________. - Answer-On
either bone at the point where the separation distance between the radius and ulna is 5-
or 8- respectively
A basic computer system includes:
1. Computer tower
2. Monitor
3. Keyboard
4. Mouse - Answer-1,2,3,&4
True or False. Excessive internal rotation of the proximal femur will result in the total
disappearance of the lesser trochanter. - Answer-True
BMC increases accordingly from ____to____. - Answer-L1 to L4
True or False. The BMD of 3 -4 continuous vertebrae is preferred for the measurement
in DXA over the BMD of 2 vertebrae averages. - Answer-True
If the actual value for the z-score were 2 standard deviations above the average, the z-
score would be____. - Answer-+2
True or False. A plus or minus sign is placed in the front of the z-score value to indicate
whether the value lies above or below the average. - Answer-True
The average value of the T-score is assigned the value of 50. If the actual value were 1
standard deviation above the average, the T score would be____. - Answer-60
The average value of the T-score is assigned the value of 50. If the actual value were 2
standard deviations below the average, the T-score would be_______. - Answer-30
What 2 factors have the greatest effect on the failure to achieve an average peak bone
density?
1. Dietary calcium deficiency
2. Lack of exercise.
3. Early menarche. - Answer-1&2
BMD based diagnostic classification should not be made:
1. If only one single vertebra can be utilized.
, 2. If only two vertebrae can be utilized.
3. If only three vertebrae can be utilized. - Answer-1
Anatomically abnormal vertebrae may be excluded from analysis if:
1. The vertebra appears clearly abnormal.
2. There is more than a 1.0 T-score difference between the vertebra in question and
adjacent vertebrae.
3. There is more than a -2.0 T-score difference between the vertebra in question and
adjacent vertebrae. - Answer-1&2
True or False. The term osteopenia means low bone mass or low bone density. -
Answer-True
The main functions of the bone are mechanical, protective and _____. - Answer-
Supportive
The strength of bone is determined by_______. - Answer-Bone density
The percentage of trabecular bone in the skeletal system is___. - Answer-20%
Which of the following bone density techniques delivers the largest amount of radiation?
The unit of measure that is used with QCT (quantitative computed tomography) is_. -
Answer-mg/cm3
The DXA system that employs a rare earth filtered x-ray source utilizes a ____detector.
- Answer-Pulse counting
When performing an x-ray of the forearm in the AP projection, the placement of the
hand should be in _____. - Answer-Supination
Z-scores in BMD measurements are relative percent values for ____________. -
Answer-Age matched normal controls
DPA is a method that uses_______. - Answer-One isotope with two photon emissions
What is the main purpose of bone densitometry? - Answer-Diagnosing osteoporosis by
detecting low bone mass before fractures occur.
What disease is characterized by hypersensitivity to gluten? - Answer-Adult sprue
Two dimensional representation of a three dimensional object. - Answer-Area
(projectional) technique
The hormone secreted by the thyroid that decreases the osteoclasts activity and
increases the osteoblasts activity is? - Answer-Calcitonin
