Contrast

Question 1

Mechanical index eq

Answer 1

Peak acoustic negative pressure / sqrt frequency

Question 2

Mechanical Index levels

Answer 2

Very low 0.1 to <0.2
Low 0.2 to <0.3
Intermediate 0.3 to 0.5
High (Flash) >0.5

Question 3

Swirling artifact

Answer 3

MI too high

Question 4

Attenuation artifact

Answer 4

Too much contrast, can’t see mid / base

Question 5

Contrast pulse sequencing

Answer 5

Very low MI, alternating polarity and amplitude

Question 6

Pulse inversion doppler

Answer 6

Transmitting pulses of alternating polarity

Question 7

Power modulating

Answer 7

Transmitting pulses of alternating amplitude

Question 8

Myocardial contrast perfusion vs. SPECT

Answer 8

Higher sensitivity, Lower specificity for angiographically significant CAD

Question 9

Back pain with contrast

Answer 9

Seen with definity, usually related to lipid shell composition, resolves with discontinuation

Question 10

Very low MI detects

Answer 10

Primarily nonlinear behavior from micro bubbles

Question 11

Left sided contrast injection left atrial then right atrial enhancement

Answer 11

Left SVC with unroofed coronary sinus

Question 12

Normal myocardial contrast replenishment at rest

Answer 12

4-5 seconds

Question 13

Normal myocardial contrast replenishment in stress

Answer 13

2 seconds