CET Technology & Digital Tools 3 — Questions and Answers
Question 1: What is the primary function of the 'reject' control on an echocardiography machine?
- Eliminates low-amplitude signals below a set threshold (Correct answer)
- Increases the dynamic range of the image
- Adjusts the pulse repetition frequency
- Controls transducer focal zone depth
Correct answer: Eliminates low-amplitude signals below a set threshold
The reject control suppresses low-level noise and clutter signals beneath a user-defined amplitude threshold, cleaning the image background.
Question 2: In 3D echocardiography, which acquisition mode captures a full-volume dataset triggered over multiple cardiac cycles?
- Multi-beat full-volume (Correct answer)
- Single-beat live 3D
- Zoom mode
- Color compare mode
Correct answer: Multi-beat full-volume
Multi-beat full-volume acquisition stitches together sub-volumes from 4–7 gated heartbeats to achieve high volume rate and spatial resolution.
Question 3: Which measurement tool in echo analysis software uses the proximal isovelocity surface area (PISA) method?
- Regurgitant orifice area calculation (Correct answer)
- Left ventricular mass measurement
- Tricuspid annular plane systolic excursion (TAPSE)
- E/A ratio computation
Correct answer: Regurgitant orifice area calculation
PISA calculates the effective regurgitant orifice area (EROA) by measuring the radius of the convergence hemisphere on color Doppler.
Question 4: When using tissue Doppler imaging (TDI) to measure myocardial velocities, what signal processing change distinguishes TDI from standard color Doppler?
- High-pass filters removed; low-pass filters applied to retain low-velocity, high-amplitude myocardial signals (Correct answer)
- Higher pulse repetition frequency to detect fast flow
- Increased dynamic range to capture blood flow signals
- Wider sector angle for full-chamber coverage
Correct answer: High-pass filters removed; low-pass filters applied to retain low-velocity, high-amplitude myocardial signals
TDI reverses conventional Doppler filtering by removing high-pass wall filters to capture slow, high-amplitude myocardial motion while rejecting fast blood-flow signals.
Question 5: A technician needs to send echo reports to a cardiologist's electronic health record system. Which messaging standard is typically used for structured report data (not image transfer)?
- HL7 v2.x or FHIR (Correct answer)
- DICOM C-STORE
- TCP/IP raw socket
- FTP file transfer
Correct answer: HL7 v2.x or FHIR
HL7 v2.x messages (such as ORU^R01) or FHIR resources are the standards for transmitting structured clinical reports and results between healthcare IT systems.
Question 6: In contrast echocardiography, which technology in the imaging system must be activated to optimally visualize ultrasound contrast agents?
- Harmonic imaging with low mechanical index (Correct answer)
- Continuous wave Doppler mode
- High mechanical index pulsed imaging
- M-mode cursor recording
Correct answer: Harmonic imaging with low mechanical index
Low mechanical index harmonic imaging detects the non-linear oscillation of contrast microbubbles while minimizing bubble destruction.
Question 7: Which network standard defines the maximum data payload size per Ethernet frame and is relevant when large DICOM echo files are transmitted over hospital networks?
- MTU (Maximum Transmission Unit) (Correct answer)
- VLAN tagging
- SNMP trap settings
- DNS lookup time
Correct answer: MTU (Maximum Transmission Unit)
MTU defines the largest data frame (typically 1500 bytes for standard Ethernet) that can be sent without fragmentation, affecting DICOM transfer efficiency.
CET Technology & Digital Tools 3
What is the primary function of the 'reject' control on an echocardiography machine?