SonoSim Exam Questions and Correct Verified Answers Graded A+
High impedance produces a bright image - Answer-Strong reflection of sound waves = high
amplitude = bright/echogenic image
Low impedance produces a dark image - Answer-Paucity of returning sound waves = low
amplitude = dark/anechoic image
High-frequency transducer - Answer-a. Good for superficial structures
b. Increasing frequency improves resolution, but at the expense of penetration
Lower-frequency transducer - Answer-Good for structures deep within the body
Unit of measurement of transducer - Answer-megahertz (MHz)
Transducer indicator - Answer-a. Imaging convention to direct cephalad or to patient's
anatomic right side
b. Transverse orientation (anatomic right direction)
c. Longitudinal orientation (cephalad direction)
Attenuation- artifact - Answer-Progressive weakening of sound as it travels through the body
High attenuation (clean shadowing) - Answer-i. When sound encounters high-attenuating
tissue, echoes are weakened posteriorly, and an acoustic shadow results
ii. Occurs deep to highly-attenuating tissue
Ex. Gallstones
Low attenuation (increased through-transmission) - Answer-i. Sound waves can travel
through fluid-filled organs with little attenuation
ii. When sound encounters low-attenuating tissue, echoes are enhanced posteriorly
, iii. Bladder can be used as an acoustic window
1. Ex. Sound can travel through fluid in the urinary bladder with little attenuation
2. Structures posterior to bladder become hyperechoic
iv. Enhancement- strengthening of echoes distal to a weakly-attenuating structure
Reverberation (multiple equidistantly spaced reflections) - Answer-a. Multiple reflections
between transducer and object being imaged, or within a structure
b. Caused by a strongly reflective and smooth surface
c. Appears as recurrent, bright, horizontal echoes at equidistant intervals
Comet-tail artifact- aka B-line artifact or lung rocket - Answer-a. Reverberation artifact
Mirror image artifact - Answer-a. Sound resonates between pleural-air interface and liver
multiple times with delayed signal transmission
b. US machine misinterprets the extra time as something further afield and thus plots more
liver tissue
c. Mirror-image artifact present = no fluid in the chest
i.Ex. Very helpful in diagnosing hemothorax and pleural effusion
Ultrasound waves - Answer-a. B-mode (greyscale) imaging depicts internal tissue structure
b. Doppler imaging illustrates the presence, direction, speed, and character of blood flow
c. Doppler effect/shift- change in wave frequency caused by motion of wave source,
observer, or reflector
i. US waves are audible sound waves
ii. Ex. Moving train or vehicle
iii. Higher pitch as it approaches observer
iv. Lower pitch as it moves away from observer
Advantages of ultrasound guidance for peripheral venous access - Answer-a. Readily
visualizes vascular structures
High impedance produces a bright image - Answer-Strong reflection of sound waves = high
amplitude = bright/echogenic image
Low impedance produces a dark image - Answer-Paucity of returning sound waves = low
amplitude = dark/anechoic image
High-frequency transducer - Answer-a. Good for superficial structures
b. Increasing frequency improves resolution, but at the expense of penetration
Lower-frequency transducer - Answer-Good for structures deep within the body
Unit of measurement of transducer - Answer-megahertz (MHz)
Transducer indicator - Answer-a. Imaging convention to direct cephalad or to patient's
anatomic right side
b. Transverse orientation (anatomic right direction)
c. Longitudinal orientation (cephalad direction)
Attenuation- artifact - Answer-Progressive weakening of sound as it travels through the body
High attenuation (clean shadowing) - Answer-i. When sound encounters high-attenuating
tissue, echoes are weakened posteriorly, and an acoustic shadow results
ii. Occurs deep to highly-attenuating tissue
Ex. Gallstones
Low attenuation (increased through-transmission) - Answer-i. Sound waves can travel
through fluid-filled organs with little attenuation
ii. When sound encounters low-attenuating tissue, echoes are enhanced posteriorly
, iii. Bladder can be used as an acoustic window
1. Ex. Sound can travel through fluid in the urinary bladder with little attenuation
2. Structures posterior to bladder become hyperechoic
iv. Enhancement- strengthening of echoes distal to a weakly-attenuating structure
Reverberation (multiple equidistantly spaced reflections) - Answer-a. Multiple reflections
between transducer and object being imaged, or within a structure
b. Caused by a strongly reflective and smooth surface
c. Appears as recurrent, bright, horizontal echoes at equidistant intervals
Comet-tail artifact- aka B-line artifact or lung rocket - Answer-a. Reverberation artifact
Mirror image artifact - Answer-a. Sound resonates between pleural-air interface and liver
multiple times with delayed signal transmission
b. US machine misinterprets the extra time as something further afield and thus plots more
liver tissue
c. Mirror-image artifact present = no fluid in the chest
i.Ex. Very helpful in diagnosing hemothorax and pleural effusion
Ultrasound waves - Answer-a. B-mode (greyscale) imaging depicts internal tissue structure
b. Doppler imaging illustrates the presence, direction, speed, and character of blood flow
c. Doppler effect/shift- change in wave frequency caused by motion of wave source,
observer, or reflector
i. US waves are audible sound waves
ii. Ex. Moving train or vehicle
iii. Higher pitch as it approaches observer
iv. Lower pitch as it moves away from observer
Advantages of ultrasound guidance for peripheral venous access - Answer-a. Readily
visualizes vascular structures