Introduction to Orthopedic Imaging

Question 1

Three Basic Forms of Imaging

Answer 1

Transmission imaging
Reflection imaging
Emission imaging

Question 2

• Radiography (x-ray)
• Fluoroscopy
• Computed tomography (CT)

Answer 2

Transmission imaging

Question 3

Ultrasound

Answer 3

Reflection imaging

Question 4

• Magnetic resonance (MR)

* Nuclear medicine

Answer 4

Emission imaging

Question 5

• A beam of energy (x-ray) is passed through the

body

Answer 5

Transmission Imaging

Question 6

simply a permanent
film record of the differential
attenuation of the x-ray beam by
the various tissues inside the body

Answer 6

radiograph

Question 7

Based on sound waves, which are sent into the body
and reflected back to the sound head – similar to an
echo

Answer 7

reflection imaging

Question 8

Structures that have low density (e.g., fluid) do not

reflect many sound waves back and appear ______ in reflective imaging

Answer 8

dark

Question 9

many, if not all, of the sounds waves back and are Structures that are very dense (e.g., bone) reflect _____ in reflective imaging

Answer 9

bright

Question 10

various tissues of the body emit a particular
frequency, which is detected and mapped by a
computer to generate an image

Answer 10

Emission imaging

Question 11

• Trauma (recent or old)
• Unexplained weight loss
• Night pain

Answer 11

red flag

Question 12

• Neuromotor deficit
• Suspicion of inflammatory arthritis
• History of malignancy

Answer 12

red flag

Question 13

• FUO (fever of unknown origin) • Abnormal blood work • Deformity (i.e. scoliosis)

Answer 13

red flag

Question 14

• Failure to respond normally to therapy • Medicolegal implications

Answer 14

red flag

Question 15

• > 50 years of age • Pediatric patient with non-traumatic pain • Drug/Alcohol abuse • Corticosteroid use

Answer 15

yellow flag

Question 16

• Unavailability of any other kind of imaging • Unavailable, lost or technically inadequate previous
studies • “Dated” previous studies • Research (need IRB)

Answer 16

yellow flag

Question 17

• Constitutional or systemic disease • Recent immigration • Therapeutic risk assessment (i.e. Down’s Syndrome)

Answer 17

yellow flag

Question 18

• Patient education • “Routine screening” • Habit • A discharge status assessment

Answer 18

non-indicator

Question 19

• Routine biomechanical analysis • Pre-employment screening • Inadequate equipment (outdated/abused) • Non-trained personnel (CA)

Answer 19

non-indicator

Question 20

• Financial gain • Recent history of high-level radiation exposure • Pregnancy

Answer 20

non-indicator

Question 21

In many situations, the first step in the diagnostic
imaging process should be ______
whenever possible!

Answer 21

plain film radiography

Question 22

Great for musculoskeletal,
abdominal and chest
pathology

Answer 22

plain film radiography

Question 23

contraindications of ______:
• Ionizing radiation
• Limit the use on children • Avoid use on pregnant or potentially pregnant women

Answer 23

plain film radiography

Question 24

plain film radiography: ABCS

Answer 24

• Alignment
• Bone
• Cartilage space
• Soft tissue

Question 25

positive fat pad sign indicates

Answer 25

fluid in the joint

Question 26

avascular necrosis of lunate

Answer 26

keinbach's dz

Question 27

gallstone seen _____ on xray

Answer 27

15%

Question 28

renal stone seen ____ on xray

Answer 28

85%

Question 29

The use of x-ray is

Answer 29

DECLINING

Question 30

Spine assessment, especially generalized back pain

Answer 30

MR

Question 31

Evaluation of nasal/paranasal sinuses for infection

Answer 31

CT

Question 32

Evaluation of the kidneys

Answer 32

CT

Question 33

kidney function

Answer 33

US, MR, or nuclear medicine

Question 34

Abdominal pain

Answer 34

CT and MRI

Question 35

Skull injuries

Answer 35

CT

Question 36

GREAT for imaging: | • Internal joint derangement • Musculoskeletal soft tissues • Bone marrow

Answer 36

MR

Question 37

BAD for imaging: • Subtle calcifications/bony fragments • Anatomy that may be obscured by motion

Answer 37

MR

Question 38

``` contra of _____: 1st tri of pregnancy >300lb ferromagnetic artifacts cardiac pacemakers cochlear implants ```

Answer 38

MR

Question 39

Strengths • Anatomic detail • Fat, subacute hemorrhage • Meniscal pathology • Use with Gadolinium (Gd) enhancement, with or without fat saturation • Marrow pathology better than some other pulse sequences

Answer 39

MR T1

Question 40

Weaknesses • Poor detection of soft tissue edema and other T2 sensitive pathology • Not as sensitive as STIR or fast spin echo T2 with fat sat for marrow pathology

Answer 40

MR T1

Question 41

Strengths • Detection of fluid and many pathologic processes • T2 spine scans act as a myelographic study without the need for intrathecal contrast administration

Answer 41

MR T2

Question 42

Weaknesses | • Long imaging times – a fast spin echo will reduce T2 imaging

Answer 42

MR T2

Question 43

Strengths | • Anatomic detail • Meniscal pathology

Answer 43

Proton Density - PD

Question 44

Weaknesses | • Poor detection of fluid and marrow pathology

Answer 44

Proton Density - PD

Question 45

Strengths | • Ligaments • Tendons • Loose bodies and subtle hemorrhage • 3D imaging

Answer 45

Gradient echo – GE or T2*

Question 46

Weaknesses | • Poor detection of marrow pathology at high field strengths • Metallic hardware – increases artifacts

Answer 46

Gradient echo – GE or T2*

Question 47

Strengths | • Marrow and soft tissue edema

Answer 47

Short Tau Inversion Recovery – STIR

Question 48

Weaknesses • Should not be used with Gadolinium • Doesn’t perform well with large patients or large fields of view

Answer 48

Short Tau Inversion Recovery – STIR

Question 49

• Specialized form of MR that allows non-invasive imaging of the cardiovascular system • Allows examination of this system in instances where angiography is contraindicated

Answer 49

MRA = MR angiography

Question 50

MR Contrast agent

Answer 50

“GAD” Gadolinium diethylene-triamine-pentaacetic acid (Gd-DTPA)

Question 51

Paramagnetic contrast agent that enhances the MR signal intensity of various tissues following its intravenous or intra- articular administration • Useful in the evaluation of inflammatory or neoplastic lesions

Answer 51

Gadolinium