Important ARDMS AB-Abdomen Exam Questions

Answer: B

Explanation:

The ultrasound images show two views of the same groin region --- one without compression (left image labeled ''W/O COMPRESSION'') and one with graded probe compression (right image labeled ''W/ COMPRESSION'').

In the non-compression image, a hypoechoic mass-like structure is visible protruding through the abdominal wall, consistent with a hernia sac. On the compression image, the herniated content is no longer visible, indicating that the contents have been pushed back into the abdominal cavity. This is the hallmark feature of a reducible hernia.

Key characteristics of a reducible hernia on ultrasound:

Herniated contents are visible without pressure.

Contents disappear or reduce back into the abdomen with graded probe compression or Valsalva release.

Typically includes omental fat or bowel, but reduction confirms lack of incarceration or strangulation.

Comparison of answer choices:

Fat only refers to the hernia content type, not the behavior or reducibility shown here.

Reducible --- Correct. The change in hernia appearance between images demonstrates successful reduction with compression.

Incarcerated hernia would remain visible and not compressible or reducible.

Strangulated hernia would show signs of ischemia (bowel wall thickening, absent perfusion, hyperechoic mesentery), and would also not reduce with compression.

Radswiki. Ultrasound evaluation of hernia. Radiopaedia.org

Rumack CM, Wilson SR, Charboneau JW, Levine D. Diagnostic Ultrasound, 5th ed. Elsevier; 2017.

AIUM Practice Parameter for the Performance of a Focused Ultrasound Examination for Hernia (2021)

Answer: D

Explanation:

The ultrasound image demonstrates multiple parallel echogenic lines within the gallbladder lumen, extending distally and diminishing in intensity. These equidistant lines are classic for a reverberation artifact.

Reverberation occurs when the ultrasound beam reflects multiple times between two strong reflectors (such as the anterior gallbladder wall and the transducer), creating repeating echoes that appear as equally spaced lines. This is frequently seen in:

The gallbladder (especially when collapsed or near the wall)

Near air-filled structures

With metallic objects or surgical clips

Reverberation does not represent a true anatomical structure and should be distinguished from real pathology.

Comparison of answer choices:

A . Banding refers to speed displacement or slice-thickness artifacts and typically does not appear as repetitive lines.

B . Shadowing is a dark band posterior to highly attenuating structures like gallstones or bone, not present here.

C . Attenuation is a general term for the reduction in sound energy as it travels---posterior acoustic shadowing is one type.

D . Reverberation --- Correct. The characteristic bright, parallel lines within the gallbladder lumen confirm this artifact.

Kremkau FW. Sonography Principles and Instruments, 9th ed. Elsevier; 2015.

Rumack CM, Wilson SR, Charboneau JW, Levine D. Diagnostic Ultrasound, 5th ed. Elsevier; 2017.

Hagen-Ansert SL. Textbook of Diagnostic Sonography, 8th ed. Elsevier; 2017.

Answer: A

Explanation:

The spectral Doppler image demonstrates excessive noise along the baseline, including a ''fuzzy'' or filled-in spectral window. This artifact is known as spectral broadening or ''blossoming,'' and it typically results from excessive Doppler gain.

When Doppler gain is set too high, it amplifies not only the true Doppler signal but also the background noise. This results in a falsely broadened waveform that can obscure diagnostic information such as peak velocities or flow turbulence. The best way to correct this artifact is to reduce the Doppler gain (Option A).

Key points regarding gain-related artifact:

Excessive gain exaggerates spectral display by amplifying weak signals and noise.

Reducing gain restores the clarity of the spectral window and accurate envelope definition.

The goal is to optimize gain just enough to see the real flow signals without cluttering the display.

Differentiation from other options:

B . Adjust baseline: Useful in avoiding aliasing but does not affect gain-related noise.

C . Increase wall filter: Removes low-frequency signals from vessel wall motion but not background spectral noise.

D . Increase pulse repetition frequency (PRF): Used to reduce aliasing in high-velocity flow, not to address gain-related spectral clutter.

Kremkau FW. Sonography: Principles and Instruments. 9th Edition. Elsevier, 2015. Chapter: Doppler Principles, pp. 189--193.

Rumack CM, Wilson SR, Charboneau JW, Levine D. Diagnostic Ultrasound. 5th Edition. Elsevier, 2018. Chapter: Doppler Artifacts, pp. 65--67.

American Institute of Ultrasound in Medicine (AIUM) Doppler Ultrasound Practice Guidelines, 2020.

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Answer: A

Explanation:

The ultrasound image shows a measured common bile duct (CBD) diameter of 7.9 mm in a postcholecystectomy patient. In patients who have undergone cholecystectomy, mild dilation of the CBD is considered normal and is a well-recognized post-surgical change.

Normal upper limits for CBD diameter:

In patients with a gallbladder: 6 mm is generally considered normal.

In postcholecystectomy patients: up to 10 mm is considered within normal limits, as the CBD compensates for the absence of the gallbladder and slightly enlarges over time.

With aging, the CBD may enlarge by approximately 1 mm per decade after age 60.

Therefore, a CBD diameter of 7.9 mm in a patient without a gallbladder is considered normal.

Differentiation from other options:

B . Dilated: This would typically refer to a CBD diameter >10 mm in postcholecystectomy patients, or >6 mm in patients with an intact gallbladder.

C . Inflamed: Inflammation refers to wall thickening or hyperemia, which is not evaluated simply by measuring diameter.

D . Atretic: Describes a congenitally absent or severely narrowed duct --- not applicable here.

Rumack CM, Wilson SR, Charboneau JW, Levine D. Diagnostic Ultrasound. 5th Edition. Elsevier, 2018. Chapter: Biliary System, pp. 143--146.

American Institute of Ultrasound in Medicine (AIUM) Practice Parameter for the Performance of a Hepatobiliary Ultrasound Examination, 2020.

Radiopaedia.org. Common bile duct: https://radiopaedia.org/articles/common-bile-duct

Answer: C

Explanation:

The ultrasound image provided shows a transverse view of the abdominal aorta, with a clearly measured aortic diameter of 5.71 cm. A normal adult abdominal aorta should measure less than 3.0 cm in anterior-posterior diameter. Any measurement exceeding this threshold is defined as an abdominal aortic aneurysm (AAA).

In this case, the dilation is well beyond the 3.0 cm threshold, confirming the presence of an aneurysm. The rounded, anechoic/heterogeneous central lumen surrounded by echogenic arterial wall layers further supports this diagnosis.

Comparison of answer choices:

A . Stenosis: Would show a narrowed lumen with turbulent, aliasing flow on Doppler, not a dilated aorta.

B . Dissection: Typically shows an echogenic intimal flap separating true and false lumens; no flap is visible here.

C . Aneurysm: Correct. The aorta's transverse diameter (5.71 cm) confirms the presence of an aneurysm.

Rumack CM, Wilson SR, Charboneau JW, Levine D. Diagnostic Ultrasound, 5th ed. Elsevier; 2017.

Society for Vascular Surgery Guidelines: Management of Abdominal Aortic Aneurysms (Chaikof et al., J Vasc Surg, 2018).

Hagen-Ansert SL. Textbook of Diagnostic Sonography, 8th ed. Elsevier; 2017.