Ultrasound Physics - 21\quality Assurance

Front 1

The routine, period evaluation of an ultrasound system to guarantee optimal image quality, is called what?

Back 1

Quality Assurance

Front 2

Quality assurance evaluations must be performed ___ & ___?

Back 2

Periodically & Routinely

Front 3

Quality assurance is a ___ & ___ necessity

Back 3

Medical & Legal

Front 4

Name the four requirements of a quality assurance program

Back 4

1. system assessment
2. repairs
3. preventive maintenance
4. record keeping

Front 5

Name the five goals of a quality assurance program

Back 5

1. proper equipment operation
2. detect gradual changes
3. minimize downtime
4. reduce non-diagnostic exams
5. reduce repeat exams

Front 6

Name 4 devices that enable the sonographer to perform quality assurance on a system

Back 6

1. AIUM 100 mm test object
2. Tissue Equivalent Phantom
3. Doppler Phantom
4. Beam Profile/Slice Thickness Phantom

Front 7

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

Back 7

AIUM 100 mm Test Object

Front 8

What is being evaluated when the pins in the AIUM 100 mm Test Object are parallel to the beam's main axis?

Back 8

Axial Resolution

Front 9

What is being evaluated when the pins in the AIUM 100 mm Test Object are perpendicular to the beam?

Back 9

Lateral Resolution

Front 10

What is being evaluated by comparing the distances between reflections on the display with the actual distances in the AIUM 100 mm Test Object?

Back 10

Electronic Caliper Accuracy

Front 11

What is being evaluated on the AIUM 100 mm Test Object by scanning the pins located at the top?

Back 11

Dead Zone

Front 12

Why is the AIUM Test Object less useful for real-time systems today?

Back 12

They lack tissue's attenuation properties and thus are unable to evaluate grayscale

Front 13

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

Back 13

Tissue Equivalent Phantom

Front 14

Name the QA device:
- speed of sound of tissue
- attenuation of tissue
- scattering characteristics of tissue
- echogenicity of tissue

Back 14

Tissue Equivalent Phantom

Front 15

Name the QA device used in evaluating blood flow (pulsed, continuous, power)

Back 15

Doppler Phantom

Front 16

What is the QA device that propels fluid through vessels embedded within a Tissue Equivalent Phantom called?

Back 16

Doppler Phantom

Front 17

This QA device contains a diffuse scattering plane at an angle to the incident sound beam, with a medium that mimics soft tissue

Back 17

Slice Thickness Phantom

Front 18

The evaluation of slice thickness is also called what?

Back 18

Elevational Resolution

Front 19

Which type of resolution degrades if beam slices are too thick, making cystic structures appear filled in?

Back 19

Spatial Resolution

Front 20

This refers to the ability of a system to display low-level echoes

Back 20

Sensitivity

Front 21

This level of sensitivity assesses the weakest echo signal that is accurately displayed & the detection of low-level echoes in the far field

Back 21

Minimum Sensitivity

Front 22

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

Back 22

Minimum Sensitivity

Front 23

This level of sensitivity assesses all the pins, solid masses and cystic structures in the phantom, ensuring all are accurately displayed

Back 23

Normal Sensitivity

Front 24

This level of sensitivity is evaluated with the output power and amplification set to the highest practical levels

Back 24

Maximum Sensitivity

Front 25

Sensitivity is also assessed when the sonographer changes echo ___ from barely visible to full ___ (saturation)

Back 25

Brightness

Front 26

This results from the transducer ringing and the time it takes to switch from transmit to receive

Back 26

Dead Zone

Front 27

This is the region close to the transducer where images are inaccurate

Back 27

Dead Zone

Front 28

Which transducers have a thinner dead zone?

Back 28

High Frequency

Front 29

Besides changing transducer frequency, what else can be done to image very superficial structures?

Back 29

Acoustic Standoff/Gel Pack
(50cc bag of IV fluid works well)

Front 30

A cracked crystal, detached backing material, or longer pulse duration may present as what during QA assessments?

Back 30

Dead Zone Thickening (gradual)

Front 31

The ability of the system to place reflections in proper positions while imaging from different orientations, is called what?

Back 31

Registration Accuracy

Front 32

The system's accuracy in placing reflectors at correct depths located parallel to the sound beam, is called what?

Back 32

Vertical Depth Calibration

Front 33

The system's accuracy in placing reflectors at correct depths in A-Mode, B-Mode, M-Mode, and 2D imaging, is called what?

Back 33

Depth Calibration

Front 34

The system's accuracy in placing echoes in their correct position perpendicular to the sound beam

Back 34

Horizontal Calibration

Front 35

The depth where the intensity is the greatest and the beam is the narrowest, is called what?

Back 35

Focus

Front 36

What is the zone surrounding the focus called?

Back 36

Focal Zone

Front 37

Which resolution is best within the focal zone?

Back 37

Lateral Resolution

Front 38

The smallest distance at which two phantom pins parallel to the sound beam are displayed as two distinct echoes, is which resolution?

Back 38

Axial Resolution

Front 39

The minimum distance that two side-by-side phantom pins are displayed as two distinct echoes, is which resolution?

Back 39

Lateral Resolution

Front 40

This describes the system's ability to display similar reflectors in the phantom with echoes of equal brightness, regardless of depth

Back 40

Uniformity
Compensation Operation

Front 41

T/F: adjustments to the display device alter the appearance of the image on all output devices

Back 41

False