Overview of Imaging

Question 1

Two-dimensional imaging that can visualize down to 2-4 mm

Answer 1

X-ray

Question 2

Has the problem that all organ/fluid density looks similar (e.g. tumor, fluid, liver, pneumonia)

Answer 2

X-Ray

Question 3

Based on sound-wave reflection

-sound reflected by air and hard objects

Answer 3

Ultrasound

Question 4

Travels unimpeded through fluid and is partially reflected by solid organs

Answer 4

Ultrasound

Question 5

Areas with bone (brain) and lots of air (lungs/abd) can be hard to visualize with

Answer 5

Ultrasound

Question 6

X-ray with intravascular contrast, two-dimensional or three-dimensional

Answer 6

Angiography

Question 7

Angiography can visualize to less than

Answer 7

1 mm

Question 8

Differentiates blood in vessel (or rupture) from surrounding tissues

-Very expensive

Answer 8

Angiography

Question 9

Used for angiography and can cause acute allergic reactions and thyroid problems

Answer 9

Iodinated contrast toxicity

Question 10

Currently is more therapeutic than diagnostic. Used for embolization to stop bleeding, dilitation of narrowed artery, and chemoembolization

Answer 10

Angiography

Question 11

Differentiates tissues of differing Hounsfield units (many more gradations than plain Xray)

Answer 11

CT

Question 12

Contrast shows areas of increased blood flow or inflammation, can do angiography

Answer 12

CT

Question 13

Administration of radiation-emitting material, with subsequent scanning for emission

Answer 13

Nuclear medicine

Question 14

Visualization often less fine than other modalities (esp the two-dimensional)

Answer 14

Nuclear medicine

Question 15

Common uses – myocardium, pulmonary embolism, cancer/inflammation

Answer 15

Nuclear medicine

Question 16

Three-dimensional MR

• Can visualize <1mm
• Mostly differentiates tissues by water content and arrangement

Answer 16

MRI

Question 17

Highlights areas of inflammation in an MRI, may use for angiography (or not – “blank blood” technique)

Answer 17

Gadolinium

Question 18

What are two types of MRI toxicity?

Answer 18

Ferromagnetic and Gadolinium

Question 19

Can deposit long-term in tissues

Answer 19

Gadolinium

Question 20

Can cause rare nephrogenic systemic fibrosis with deposits in patients with severe renal disease

Answer 20

Gadolinium

Question 21

For suspected pneumonia, which test would we use first?

Answer 21

Chest X-ray (CXR)

Question 22

Two radiologists will disagree on a CXR of pneumonia

Answer 22

10-20% of the time

Question 23

For a CXR for pneumonia, what is the

1. ) Sensitivity?
2. ) Specificity?

Answer 23

1. ) 64-78%

2. ) 59-93%

Question 24

Not curable by surgery if involving the mediastinum

Answer 24

Lung cancer

Question 25

BEST test for lung cancer mediastinal staging is

Answer 25

PET/CT

Question 26

What is the reference standard for hepatocellular carcinoma?

Answer 26

Histopathology, or follow-up with CT or MRI

Question 27

One population at higher risk from radiation is patients with

Answer 27

Renal dysfunction

Question 28

What are two complications from radiation seen in patients with renal dysfunction?

Answer 28

Contrast nephropathy and nephrogenic systemic fibrosis

Question 29

In a pregnant individual, an MRI with gadolinium can result in

Answer 29

Still birth and neonatal disease

Question 30

Individuals with thyroid problems are at higher risk for imaging that utilizes

Answer 30

Iodinated contrast

Question 31

What is the 90-day mortality risk for patients undergoing an nephrectomy?

-Increased risk of chronic renal failure

Answer 31

4.3%

Question 32

Sensitivity tends to correlate negatively with specificity for

Answer 32

Incidentalomas