Diagnostic Imaging (Exam 1)

Question 1

What is an X-Ray?

Answer 1

Plain film or conventional radiograph, it is a negative

Question 2

What are the positions for radiographs?

Answer 2

AP
PA
Lateral
Oblique
Sunrise
Open Mouth

Question 3

More dense objects the (BLANK) absorption of x-ray and (BLANK) exposure of film

Answer 3

greater, less

Question 4

More dense of a tissue the (BLANK) x-rays penetrate the tissue to expose the film

Answer 4

Less

Question 5

Radiolucent:
(BLANK) Density
(BLANK) Exposure of film
Bright or Dark?

Answer 5

Low Density
High Exposure
Dark

Question 6

Radiopague
(BLANK) Density
(BLANK) Exposure of film
Bright or Dark?

Answer 6

High Density
Low Exposure
Bright

Question 7

What are the ABC’s of X-ray interpretation?

Answer 7

Alignment & Adequacy
Bone
Cartilage, Joints, Soft Tissues

Question 8

When and why are X-rays ordered for a patient with suspected NM injury?

Answer 8

• Depends on severity of injury
• Rule out/establish bony integrity
• Check for other systems

Question 9

What are some ways of early examination of the human brain?

Answer 9

Animal Studies
Post-mortem
X-rays
Electrocephalography

Question 10

What is a pneumoencephalography?

Answer 10

X- Ray imaging following an injection of air into subarachnoid space to displace CSF & improve signal contrast

Question 11

What is a pneumoencephalography used for?

Answer 11

Visualize ventricular anomalies

Question 12

What is a cerebral angiography?

Answer 12

X-ray imaging of the blood vessels of the brain following injection of a contrast agent

Question 13

What is a cerebral angiography used for?

Answer 13

Visualize anomalies and occlusions

Question 14

What is a myelography?

Answer 14

X-ray imaging following injection of contrast into CSF to improve contrast/imaging in vertebral column/spinal cord, subarachnoid space, nerve roots

Question 15

What are some modern techniques for neuroimaging?

Answer 15

CT
MRI
Neuroangiograohy

Question 16

How does a CT work?

Answer 16

1. Uses X-ray beam and a row of detectors on opposite sides of the head.
2. The X-ray source and detector rotate around the head
3. Pt is moved through scanner and process is repeated

Question 17

How can you determine the density of tissue through a CT?

Answer 17

X-ray are partially absorbed by tissue encounters and the amount of absorption depends on the density of the tissue it passed through

Question 18

What is the benefit of the CT rotating the x-ray source?

Answer 18

X-ray is passed through same structures at many different angles

Question 19

Describe the typical CT imaging planes?

Answer 19

Not in true horizontal plane but angles upward anteriorly

Question 20

(BLANK) structures are hyper dense and appear (BLANK)

Answer 20

• Dense (bone, calcification)
• White

Question 21

(BLANK) structures are hypodense and appear (BLANK)

Answer 21

• Less dense structures (air)
• Black

Question 22

(BLANK) structures are Isodense and appear (BLANK)

Answer 22

• Intermediate density structures
• Gray

Question 23

Is a CT with intravenous contrast appropriate if an intracranial hemorrhage is suspected? And why?

Answer 23

No, b/c this adds more fluid which increases pressure which could increase bleeding

Question 24

What is injected during a CT with intravenous contrast?

Answer 24

Iodine

Question 25

What becomes hyper dense during CT with intravenous contrast?

Answer 25

Areas of increased vascularity or breakdown of blood-barrier

Question 26

What is window width?

Answer 26

Range of radio densities displayed on an image

Question 27

What is window level?

Answer 27

Central density displayed on an image

Question 28

General: What is an MRI?

Answer 28

Noninvasive technique that uses magnetic energy & radio frequency pulses to generate images

Question 29

General: How does an MRI generate an image?

Answer 29

1. Pt placed in static magnetic field 2. Radiofrequency pulse applied at right angles to magnetization 3. Radiofrequency pulse stops

Question 30

What determines the intensity of a MRI signal?

Answer 30

1. Proton density 2. T1 (longitudinal) proton relaxation times 3. T2 (transverse) proton relaxation times

Question 31

Sequence of events during image acquisition creates contrast using what 2 key parameters?

Answer 31

Time to echo (TE) Time to repetition (TR)

Question 32

What is time to echo and time to repetition?

Answer 32

TE: time at which signal is captured TR: time at which radiofrequency pulse is repeated to again displace the protons

Question 33

how will hyper intense and hypo intense structures appear?

Answer 33

Hyper: brighter Hypo: darker

Question 34

in T1 images tissues that rapidly release energy are (BLANK) and tissues slow to release energy are (BLANK)

Answer 34

Rapid: brighter (fat) Slow: Darker (water)

Question 35

in T2 images tissues that rapidly release energy are (BLANK) and tissues slow to release energy are (BLANK)

Answer 35

Rapid: darker (fat) Slow: Brighter (water)

Question 36

What does a doppler ultrasound measure and detect?

Answer 36

Measure: flow and lumen diameter of blood vessels Detects: Artery stenosis & vasospasm

Question 37

What is done during a CT angiography and what does it detect?

Answer 37

Process: Inject contrast with spinal CT scan Detects: Major artery stenosis, arterial dissection, aneurysms and vascular malformations

Question 38

What does a MRA detect?

Answer 38

Narrowing in large vessels, some aneurysms and vascular malformations

Question 39

What is electroencehphalography?

Answer 39

Recording of electrical potential generated in the brain using electrodes

Question 40

What is a SPECT/PET?

Answer 40

Single photon/position emission computed tomography

Question 41

How do Nuclear scan work?

Answer 41

Patient is made radioactive with an isotope

Question 42

What is a diagnostic ultrasound?

Answer 42

High frequency sound waves create an image of living tissues

Question 43

When are diagnostic ultrasound commonly used?

Answer 43

Abdominal imaging, obstetrics, vascular studies, and head ultrasound of infants