Free Practice Questions for ARDMS AB-Abdomen Exam

Scrotal inflammation, such as epididymitis or orchitis, typically presents with increased blood flow (hyperemia) on color Doppler sonography. This finding reflects the inflammatory process and vascular dilation. Abscesses, granulomas, or hydroceles may be present but are not as consistent or specific for inflammation.

According to AIUM Practice Parameters and Rumack’s Diagnostic Ultrasound:

“In acute inflammation, color Doppler ultrasound demonstrates prominent hyperemia of the epididymis or testis.”

The ultrasound image demonstrates a tubular, non-compressible, blind-ending structure located in the right lower quadrant (RLQ) with associated echogenic periappendiceal fat and possibly adjacent fluid or phlegmon. These features are consistent with appendicitis. Given the clinical history of fever and RLQ pain, along with the irregular borders and complex periappendiceal findings, the diagnosis of a ruptured appendix is most likely.

Key sonographic features of ruptured appendicitis include:

Non-visualization or distortion of the normal appendiceal wall architecture

Periappendiceal fluid collection or abscess

Disruption of the echogenic submucosal layer

Surrounding fat stranding (hyperechoic inflammatory changes)

Clinical correlation with fever and peritonitis

Comparison of answer choices:

A. Bowel obstruction typically shows dilated bowel loops with air-fluid levels, not a tubular structure like the appendix.

B. Intussusception presents with a target or “donut” sign in a transverse view, not a linear tubular structure.

C. Enlarged lymph nodes are usually round or oval and hypoechoic with a central echogenic hilum, without a tubular appearance.

D. Ruptured appendix — Correct. The ultrasound features and clinical presentation match.

The grayscale ultrasound image demonstrates a uniformly enlarged, hypoechoic (dark), and heterogeneous testis without signs of surrounding scrotal wall thickening or a discrete fluid collection. This pattern is highly suggestive of testicular torsion in the setting of acute scrotal pain.

Sonographic features of testicular torsion on grayscale imaging:

Enlarged testis

Diffusely hypoechoic parenchyma

Loss of normal homogeneity

Absence of internal vascular flow on Doppler imaging (not shown here but critical in confirming diagnosis)

Testicular torsion occurs due to twisting of the spermatic cord, leading to vascular compromise and eventual infarction if not promptly corrected. It is a surgical emergency and typically presents in adolescent males with sudden-onset, severe unilateral testicular pain.

Comparison of answer choices:

A. Scrotal abscess appears as a complex fluid collection with irregular margins and posterior enhancement.

B. Testicular rupture would show discontinuity of the tunica albuginea, heterogeneous texture, and often a hematocele.

C. Testicular torsion — Correct. The enlarged, hypoechoic, heterogeneous testis is characteristic, particularly in the acute phase.

D. Epididymitis typically shows an enlarged, hypervascular epididymis and may extend to the testis (epididymo-orchitis), but vascularity is usually increased rather than absent.

In percutaneous procedures such as biopsies or drainages, maintaining a sterile field is critical to avoid introducing infection. While the transducer is covered by a sterile cover, the gel placed inside this cover (between the probe and the cover) must also be sterile, as it contacts the sterile field. The transducer itself and machine controls are not sterile but are handled appropriately to avoid field contamination.

According to the AIUM Guidelines:

"Sterile coupling gel must be used inside the sterile probe cover during all invasive or percutaneous procedures." (AIUM Guidelines for Cleaning and Preparing Ultrasound Transducers, 2021).

Portal veins course horizontally within the liver and have echogenic walls due to their fibrous sheath. In contrast, hepatic veins course vertically toward the IVC and lack echogenic walls. Hepatic veins also demonstrate a triphasic waveform.

According to Rumack’s Diagnostic Ultrasound:

“Portal veins course horizontally within the liver and are easily recognized by their echogenic walls.”

The transverse ultrasound image of the liver shows a solid, hypoechoic mass located in the posterior aspect of the right lobe of the liver. In this view:

The anterior aspect of the liver is at the top of the image (near the transducer).

The posterior aspect is at the bottom (deeper).

The right lobe occupies the majority of the screen on transverse imaging when the probe is placed in the epigastrium or right upper quadrant.

Anatomically, the right lobe of the liver is divided into anterior and posterior segments by the right hepatic vein in the coronal plane. In transverse imaging:

The right anterior segment lies closer to the anterior abdominal wall.

The right posterior segment lies deeper (posteriorly).

Given that the mass is seen deep within the liver on the right side of the image, it is best localized to the right posterior segment (Segment VI or VII depending on the exact craniocaudal level).

Comparison of answer choices:

A. Left lateral is located far to the left of the image and typically appears higher and more anterior on transverse scans.

B. Left medial lies near the midline and would appear adjacent to the ligamentum teres or falciform ligament.

C. Right anterior lies closer to the transducer (top of the image), not posteriorly.

D. Right posterior — Correct. This is the segment shown deep in the right lobe of the liver.

Reducing slice (section) width improves spatial resolution, particularly elevational resolution, which enhances visualization of small, superficial structures. Lower slice width reduces off-axis beam artifacts and blurring. Wavelength depends on transducer frequency, not adjustable directly during scanning.

According to Zwiebel’s Introduction to Vascular Ultrasound:

“Reduction in slice thickness improves imaging of small superficial structures by minimizing volume averaging and improving elevational resolution.”

The most serious long-term complication of undescended testis (cryptorchidism) is an increased risk of testicular malignancy, especially seminoma. Although torsion and hernia may also occur, seminoma is the most concerning complication due to its life-threatening potential.

According to Rumack’s Diagnostic Ultrasound:

“Cryptorchidism is associated with a significantly increased risk of seminoma, the most common malignancy in undescended testes.”

Caput medusae refers to dilated paraumbilical veins due to portal hypertension. When portal venous pressure rises, collateral channels may open along the ligamentum teres and recanalized paraumbilical vein, resulting in visible dilated veins radiating from the umbilicus.

Esophageal varices (B) are gastroesophageal collaterals.

Coronary vein varices (C) involve gastric veins.

Splenic vein varices (D) are typically localized to the splenic hilum.

Reference Extracts:

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

Gore RM, Levine MS. Textbook of Gastrointestinal Radiology. 4th ed. Saunders, 2015.

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Prostate adenocarcinoma is by far the most common malignancy of the prostate gland, typically arising in the peripheral zone. Seminoma is a testicular tumor, sarcomas are rare in the prostate, and hamartomas are benign lesions.

According to Rumack’s Diagnostic Ultrasound:

“Adenocarcinoma accounts for the vast majority of prostate cancers and is typically located in the peripheral zone.”