Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
41 Cards in this Set
- Front
- Back
The routine, period evaluation of an ultrasound system to guarantee optimal image quality, is called what?
|
Quality Assurance
|
|
Quality assurance evaluations must be performed ___ & ___?
|
Periodically & Routinely
|
|
Quality assurance is a ___ & ___ necessity
|
Medical & Legal
|
|
Name the four requirements of a quality assurance program
|
1. system assessment
2. repairs 3. preventive maintenance 4. record keeping |
|
Name the five goals of a quality assurance program
|
1. proper equipment operation
2. detect gradual changes 3. minimize downtime 4. reduce non-diagnostic exams 5. reduce repeat exams |
|
Name 4 devices that enable the sonographer to perform quality assurance on a system
|
1. AIUM 100 mm test object
2. Tissue Equivalent Phantom 3. Doppler Phantom 4. Beam Profile/Slice Thickness Phantom |
|
A fluid-filled tank, offering a speed of sound identical to tissue but without tissue's attenuation properties (so greyscale cannot be evaluated). Strategically located stainless steel pins or plastic strings produce reflections
|
AIUM 100 mm Test Object
|
|
What is being evaluated when the pins in the AIUM 100 mm Test Object are parallel to the beam's main axis?
|
Axial Resolution
|
|
What is being evaluated when the pins in the AIUM 100 mm Test Object are perpendicular to the beam?
|
Lateral Resolution
|
|
What is being evaluated by comparing the distances between reflections on the display with the actual distances in the AIUM 100 mm Test Object?
|
Electronic Caliper Accuracy
|
|
What is being evaluated on the AIUM 100 mm Test Object by scanning the pins located at the top?
|
Dead Zone
|
|
Why is the AIUM Test Object less useful for real-time systems today?
|
They lack tissue's attenuation properties and thus are unable to evaluate grayscale
|
|
These have ultrasonic features similar to soft tissue, making them more suitable for evaluating grayscale, tissue texture, multi-focus, and adjustable-focus phased array transducers
|
Tissue Equivalent Phantom
|
|
Name the QA device:
- speed of sound of tissue - attenuation of tissue - scattering characteristics of tissue - echogenicity of tissue |
Tissue Equivalent Phantom
|
|
Name the QA device used in evaluating blood flow (pulsed, continuous, power)
|
Doppler Phantom
|
|
What is the QA device that propels fluid through vessels embedded within a Tissue Equivalent Phantom called?
|
Doppler Phantom
|
|
This QA device contains a diffuse scattering plane at an angle to the incident sound beam, with a medium that mimics soft tissue
|
Slice Thickness Phantom
|
|
The evaluation of slice thickness is also called what?
|
Elevational Resolution
|
|
Which type of resolution degrades if beam slices are too thick, making cystic structures appear filled in?
|
Spatial Resolution
|
|
This refers to the ability of a system to display low-level echoes
|
Sensitivity
|
|
This level of sensitivity assesses the weakest echo signal that is accurately displayed & the detection of low-level echoes in the far field
|
Minimum Sensitivity
|
|
This level of sensitivity is determined by setting the TGC flat, then increasing system gain from the minimum value to the gain when a deep rod is displayed
|
Minimum Sensitivity
|
|
This level of sensitivity assesses all the pins, solid masses and cystic structures in the phantom, ensuring all are accurately displayed
|
Normal Sensitivity
|
|
This level of sensitivity is evaluated with the output power and amplification set to the highest practical levels
|
Maximum Sensitivity
|
|
Sensitivity is also assessed when the sonographer changes echo ___ from barely visible to full ___ (saturation)
|
Brightness
|
|
This results from the transducer ringing and the time it takes to switch from transmit to receive
|
Dead Zone
|
|
This is the region close to the transducer where images are inaccurate
|
Dead Zone
|
|
Which transducers have a thinner dead zone?
|
High Frequency
|
|
Besides changing transducer frequency, what else can be done to image very superficial structures?
|
Acoustic Standoff/Gel Pack
(50cc bag of IV fluid works well) |
|
A cracked crystal, detached backing material, or longer pulse duration may present as what during QA assessments?
|
Dead Zone Thickening (gradual)
|
|
The ability of the system to place reflections in proper positions while imaging from different orientations, is called what?
|
Registration Accuracy
|
|
The system's accuracy in placing reflectors at correct depths located parallel to the sound beam, is called what?
|
Vertical Depth Calibration
|
|
The system's accuracy in placing reflectors at correct depths in A-Mode, B-Mode, M-Mode, and 2D imaging, is called what?
|
Depth Calibration
|
|
The system's accuracy in placing echoes in their correct position perpendicular to the sound beam
|
Horizontal Calibration
|
|
The depth where the intensity is the greatest and the beam is the narrowest, is called what?
|
Focus
|
|
What is the zone surrounding the focus called?
|
Focal Zone
|
|
Which resolution is best within the focal zone?
|
Lateral Resolution
|
|
The smallest distance at which two phantom pins parallel to the sound beam are displayed as two distinct echoes, is which resolution?
|
Axial Resolution
|
|
The minimum distance that two side-by-side phantom pins are displayed as two distinct echoes, is which resolution?
|
Lateral Resolution
|
|
This describes the system's ability to display similar reflectors in the phantom with echoes of equal brightness, regardless of depth
|
Uniformity
Compensation Operation |
|
T/F: adjustments to the display device alter the appearance of the image on all output devices
|
False
|