CET Echocardiography Imaging Techniques 2 — Questions and Answers
Question 1: Which transducer frequency range is most commonly used for adult transthoracic echocardiography?
- 1-2 MHz
- 2-4 MHz (Correct answer)
- 5-7 MHz
- 8-10 MHz
Correct answer: 2-4 MHz
Adult TTE typically uses 2-4 MHz transducers to balance penetration depth with adequate resolution for cardiac structures.
Question 2: In tissue harmonic imaging, the ultrasound system processes which returning frequency to create the image?
- Fundamental frequency
- Second harmonic (2× transmit frequency) (Correct answer)
- Sub-harmonic (½ transmit frequency)
- Third harmonic (3× transmit frequency)
Correct answer: Second harmonic (2× transmit frequency)
Tissue harmonic imaging uses the second harmonic frequency generated by nonlinear propagation through tissue, improving signal-to-noise ratio and reducing artifacts.
Question 3: When imaging a patient with a poor acoustic window, which maneuver can improve transthoracic image quality?
- Asking the patient to take a deep breath and hold
- Positioning the patient in the left lateral decubitus position (Correct answer)
- Having the patient sit upright
- Applying additional pressure with the transducer
Correct answer: Positioning the patient in the left lateral decubitus position
Left lateral decubitus positioning moves the heart closer to the chest wall and displaces lung tissue, substantially improving acoustic access.
Question 4: Which imaging mode provides a single-dimension, time-motion recording of cardiac structures and is ideal for precise timing of events?
- 2D imaging
- M-mode (Correct answer)
- Color Doppler
- Spectral Doppler
Correct answer: M-mode
M-mode (motion mode) displays a single line of information over time, offering excellent temporal resolution for measuring wall motion and valve timing.
Question 5: The acoustic shadow artifact seen posterior to a heavily calcified aortic valve is caused by:
- Increased gain settings
- Complete attenuation of the ultrasound beam by the dense structure (Correct answer)
- Reverberations from the transducer surface
- Side lobe artifact from adjacent structures
Correct answer: Complete attenuation of the ultrasound beam by the dense structure
Calcified structures completely attenuate the ultrasound beam, preventing sound from reaching structures beyond, creating an acoustic shadow.
Question 6: Which echocardiographic view is obtained with the transducer placed at the subxiphoid position and is particularly useful when other windows are limited?
- Parasternal long axis
- Apical four-chamber
- Subcostal four-chamber (Correct answer)
- Suprasternal notch
Correct answer: Subcostal four-chamber
The subcostal (subxiphoid) four-chamber view uses the liver as an acoustic window and is valuable in patients with COPD, obesity, or post-surgical chests.
Question 7: In 2D echocardiography, increasing the imaging depth setting will:
- Increase frame rate
- Decrease frame rate (Correct answer)
- Increase transducer frequency
- Improve near-field resolution
Correct answer: Decrease frame rate
Increasing depth requires the system to wait longer for returning echoes before firing the next pulse, reducing the number of frames displayed per second.
CET Echocardiography Imaging Techniques 2
Which transducer frequency range is most commonly used for adult transthoracic echocardiography?