What corrections must be taken to improve this scan?

[image]

a) Adjust the neck box position

b) Reanalyze the scan

c) Straighten femur and rotate internally

d) Roll patient 20 deg onto left hip

c) Straighten femur and rotate internally

To correct the positioning on the scan, the tech must straighten the femur so it is parallel to the table edge and rotate the femur internally to tuck the lesser trochanter behind the shaft.

Baseline lumbar spine analysis must include:

a) Verified patient biographical information

b) Manual adjustment of gray-scale, brightness or contrast if needed

c) L1-L4 vertebrae must be clearly separated at the disc spaces and labeled correctly

d) All the above

d) All the above

It is very important that the technologist insures the baseline scan is accurate, complete and correct. Therefore all the above points must be included.

What is the primary concern with scans that yield falsely elevated BMD?

a) There may be underlying pathologies that need attention

b) False BMD elevations can mask osteoporosis

c) False BMD readings are not possible

d) False BMD readings indicate a technical problem with the scanner

b) False BMD elevations can mask osteoporosis

The primary concern with scans that have falsely elevated BMD readings is the possibility that osteoporosis will be overlooked.

True or False

When performing a follow up (serial) scan, the technologist should use the compare or copy feature in the scanner's software.

True

This is true. The software is designed to provide a comparison against previous scans. The radiologist will have the current and previous BMD at hand when interpreting the study.

What should a tech do in the scenario where the scan shows surgical hardware as seen in the image?

[image]

a) Scan other hip for DXA study

b) Scan the forearm if both hips have hardware

c) Delete scan because it is not clinically useful

d) All of the above

d) All of the above

All of the above. A hip with surgical hardware cannot be used in a bone density study.

What is the artifact present in this image?

[image]

a) The image illustrates motion on the scan

b) This patient has a current fracture

c) The forearm is not straight and should be repositioned

d) There is a metal foreign object, such as a bracelet

a) The image illustrates motion on the scan

This image illustrates classic motion on the forearm scan. The forearm scan is the most sensitive to motion and the tech must make every effort to keep the patient from moving during scan acquisition.

What region of the forearm has the most cortical bone?

a) 10% UD

b) The entire forearm

c) 33%, approximately mid-forearm

d) The forearm is composed of trabecular bone

c) 33%, approximately mid-forearm

The 33% or 1/3 region of forearm (approximately mid-forearm), is mostly cortical bone.

All serial scans must be consistent with the baseline scan. What extra step must be taken to insure an accurate follow up hip scan?

a) Follow up scan should always be performed on fast scan mode.

b) It is not necessary to use the copy or compare function when doing serial hip scans

c) The femur rotation, shaft and centering must match the baseline scan as closely as possible

d) The neck box is not used in subsequent scans

c) The femur rotation, shaft and centering must match the baseline scan as closely as possible

Special care must be taken to match the femur rotation, shaft and centering to the baseline scan. The neck box should also match in size and shape.

What artifacts can cause elevated BMD?

a) Pathology such as scoliosis or fracture

b) Sclerosis

c) External artifacts

d) All the above

d) All the above

Each of these listed can cause elevated BMD. Prior fractures, cancer, osteoarthritis are other examples of artifacts that can impact BMD.

True or False

This image is an example of a patient with scoliosis.

[image]

False

False. This is not an example of a patient with scoliosis. The patient is not straight on the table and should be rescanned. The tech should reposition the patient before repeating the scan.

What steps must be taken to correct this image?

[image]

a) This is image is correct as is.

b) Reposition the patient and label the vertebrae correctly.

c) Adjust the bone edges.

d) Change the labels on the vertebrae and exclude L1.

b) Reposition the patient and label the vertebrae correctly.

In order to correct this image, the patient must be rescanned to include all of L1 and then the vertebrae must be labeled correctly.

This serial scan of a PA spine illustrates an evolving fracture of L1. What action must the tech take to do a comparison on this patient?

[image]

a) Keep the original scan as is and exclude L1 on the new scan

b) Serial scans of the PA spine are no longer useful for clinical treatment

c) Exclude L1 when analyzing current scan and reanalyze the previous scan also excluding L1

d) Compare the scans without excluding any vertebrae

True or False

Once the scan is complete, the technologist can allow the automated analysis feature to perform scan analysis, with no need to review the scan.

False

This statement is false. The technologist must always review the scan to be sure no manual adjustments need to be made. Always refer to manufacturer's guidelines for analysis instructions.

True or False

A correctly positioned spine scan must have equal amounts of soft tissue on either side of the spine.

True

This statement is true. It is important to be sure there are equal amounts of soft tissue on either side of the spine to get an accurate BMD.

When analyzing a hip scan, when should the technologist manipulate the bone edges and neck box?

a) The bone edges and neck box should be manually manipulated every scan

b) Only the bone edges should be manipulated after each scan

c) Only when necessary and always according to the manufacturer's specifications

d) Absolutely never

c) Only when necessary and always according to the manufacturer's specifications

The bone edges and neck box should only be manually manipulated when necessary, and always according to the manufacturer's specifications. This is especially true with the neck box as each manufacturer has strict guidelines about placement.

VFA clearly illustrates ____________________ that may not be visible on the PA spine scan.

[image]

a) Fractures

b) Scoliosis

c) Kyphosis

d) Calcified aorta

a) Fractures

VFA will clearly illustrate fractures that a PA spine scan may not demonstrate. Calcifications of the aorta can be seen on many VFA images and also may be seen on the PA spine scan.

True or False

The NHANES III database includes both PA spine and proximal femur sites.

False

This statement is false. The NHANES III only contains proximal femur skeletal site. The data gathered in this database is used as a reference population in the DXA computer software.

How many numbers should follow the decimal place (to the right) when expressing BMD in a numerical value?

a) One

b) Three

c) Two

d) Four

b) Three

The correct answer is three. BMD would be expressed numerically as 1.026 g/cm2. The T-score would have only one number following the decimal space.

What action must be taken to correct this scan?

[image]

a) Adjust the vertebral markers.

b) Select proper site for scan and rescan.

c) Adjust the bone edges and rescan.

d) Internally rotate the femur 5 inches more.

b) Select proper site for scan and rescan.

The only way to correct the scan is to select proper scan for site and rescan. The software cannot change the site once the scan is complete.

True or False

The forearm is a common site for serial scans.

False

This statement is false. The forearm is generally not used for serial scan because the rate of change typically is to slow to be useful.