UNIT 22-24

Quality assurance (QA) in ultrasound is best defined as:

A systematic program ensuring consistent system performance

The primary goal of QA is to:

Maintain image quality and measurement accuracy over time

Which of the following is an objective QA measurement?

Depth of penetration

In QA, “standards” refer to:

Acceptance criteria for performance

A tissue equivalent phantom is used to evaluate:

Acoustic properties and image performance

A decrease in depth of penetration over time most likely indicates:

Transducer degradation

The dead zone is primarily caused by:

Transducer ringing and recovery time

An increase in the dead zone would most impact:

Superficial structures

Range accuracy refers to:

Depth measurement accuracy

Which QA test evaluates Doppler velocity accuracy?

Doppler phantom

Poor uniformity on an image may indicate:

Element dropout

The ethical principle of autonomy refers to:

Respecting patient decisions

Nonmaleficence means:

Do no harm

Beneficence refers to:

Acting for patient benefit

Justice in healthcare refers to:

Equal treatment and fairness

A patient withdrawing consent requires the sonographer to:

Pause and notify the provider

Sonographers should:

Follow institutional policies regarding results disclosure

Universal precautions require:

Treating all patients as potentially infectious

Bioeffects are:

Any biological response to ultrasound

The two main categories of bioeffects are

Thermal and mechnical

Heating in tissue occurs primarily due to:

Absorption

Which tissue has the greatest heating potential?

Bone

Increasing frequency generally:

Increases heating potential

Mechanical bioeffects include:

Cavitation

Stable cavitation refers to:

Bubble oscillation

Inertial cavitation involves:

Violent bubble collapse

Cavitation likelihood increases with:

Low frequency

The thermal index (TI) indicates:

Potential for temperature rise

The mechanical index (MI) is related to:

Cavitation potential

If frequency increases while pressure is constant, MI:

Decreases

Which mode typically has the highest exposure?

Spectral doppler

The most important factor in reducing bioeffects is:

Reducing dwell time

ALARA stands for:

As Low As Reasonably Achievable

The best first steps to improve image quality safely is:

Increase gain

Spectral Doppler should be used when:

Measuring velocities and waveform

To reduce exposure during Doppler:

Minimize sampling time

Objective measurements in ultrasound QA include which of the following?

Depth of penetration

A tissue-equivalent phantom is primarily used to evaluate which parameters?

Depth of penetration, resolution, and distance accuracy

Which parameter cannot be tested using a tissue-equivalent phantom?

Blood flow velocity

A Doppler phantom is used to evaluate all of the following EXCEPT:

Axial resolution

A slice thickness phantom is used to determine:

The thickness of the imaging plane

In ultrasound QA, sensitivity refers to:

The ability to display weak echoes from deeper structures

Which factor does NOT influence system sensitivity?

Patient breathing

Normal sensitivity testing is performed:

With clinical imaging settings

Maximum sensitivity testing is performed by:

Setting gain and output power to maximum

The dead zone refers to:

The region near the transducer where echoes cannot be detected

Registration accuracy refers to:

Correct placement of echoes on the display relative to their true location

Range accuracy evaluates:

Accuracy of axial depth based on speed of sound and timing

Horizontal calibration is used to evaluate:

Lateral distance across the image

Distance measurement accuracy testing verifies:

Caliper measures known distance in axial and lateral direction

Uniformity problems may be caused by:

All of the above

Which principle of bioethics involves doing good for the patient?

Beneficence

Which principle refers to respecting a patient’s right to make decisions?

Autonomy

The primary goal of the Occupational Safety and Health Administration is to:

Protect workers from workplace hazards

You are scanning a phantom containing multiple rows of identical 5 mm spherical fluid filled structures embedded in a tissue-mimicking material. What type of resolution is best evaluated with this phantom?

Elevational

What is the primary purpose of using a standoff pad in diagnostic ultrasound?

Increase the distance between the transducer and a superficial structure so it lies within the focal zone

Using a high MI setting in contrast imaging will:

Improve the signal to noise ratio, but increase exam time

In adult imaging, what TI level allows imaging with no time limitations?

Below 1.5

In adult imaging, imaging should NEVER be performed when TI is:

Above 6

For adult patients, exam time limitations apply when TI is between:

1.5 and 6

In fetal imaging, what TI level allows no time limits?

Below 0.7

In fetal imaging, imaging should NEVER be performed when TI is:

Above 3

For fetal patients, exam time limitations apply when TI is between:

0.7 and 3

Imaging in adults should never be performed with a thermal index level at or above ___ and imaging a fetus should never be performed with a thermal index level at or above ___

6, 3

Which of the following correctly describes the sensitivity of a testing technique?

The ability of a test to detect disease when it is present

What is the proper method used to assess the size of the dead zone?

Measure from the top of the image to the depth that uniform tissue is identified

How is the detail resolution limit documented on phantom testing?

Two separate pins are displayed as a single reflector on the image