Contrast in Radiology

Question 1

How is contrast positive contrast and negative contrast observed?

Answer 1

Positive contrast: white
Negative contrast: black (due to increased attenuation)

Question 2

What are usually positive contrasts?

Answer 2

Metals

Iodinated or not iodinated (barium sulfate)

Question 3

What are usually negative contrasts?

Answer 3

Inert gases (O2, CO2)

Question 4

What contrast is used for X-ray examination of the intestine tract?

Answer 4

Barium sulfate

Not so much used in CT

Question 5

Is the absorption of iodine contrast media fast or slow?

Answer 5

Fast the peak of plasma concentration occurs within seconds.

Question 6

What contrast is used for ultrasound cardiac assessment?

Answer 6

Gas microbubbles

Sulfur hexafluoride and Octafluoropropane

Question 7

What phase is used in more CT protocols?

Answer 7

Redestribution phase

Question 8

When are dynamic studies used?

Answer 8

Brain studies after an stroke

Question 9

At what time is the excretory phase measured?

Answer 9

After 10 minuts