Pass the ARDMS RDMS AB-Abdomen Questions and answers with CertsForce

Acute tubular necrosis (ATN) is the most common cause of early graft dysfunction following renal transplantation. It results from ischemia-reperfusion injury during the transplantation process. Ultrasound findings may be nonspecific but Doppler may show elevated resistive indices.

Ureterocele (A) is a congenital anomaly.

Transplant artery stenosis (C) is a late complication.

Transitional cell carcinoma (D) is rare and not typically an early complication.

Reference Extracts:

Middleton WD, Kurtz AB, Hertzberg BS. Ultrasound: The Requisites. 3rd ed. Elsevier, 2015.

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

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The FAST exam is primarily used to detect free intraperitoneal or pericardial fluid in trauma patients, serving as a rapid, bedside assessment tool. While organ injuries may be suspected, the FAST exam is not primarily designed to assess for solid organ lacerations.

According to AIUM and ACEP guidelines:

“The primary goal of the FAST exam is to detect the presence of free fluid suggestive of hemorrhage in trauma patients.”

The ultrasound image demonstrates a heterogeneous and echogenic spleen with evidence of atrophy and multiple areas of calcification—consistent with autosplenectomy. This appearance is classically associated with chronic sickle cell anemia.

In sickle cell disease, repeated vaso-occlusive episodes result in infarctions, fibrosis, and progressive calcification of the spleen. Over time, this leads to functional asplenia or complete autosplenectomy (involution and shrinkage of the spleen). The hallmark sonographic features include:

A small, echogenic spleen

Multiple coarse calcifications

Irregular contour or atrophic appearance

These findings are not typically seen in other conditions:

A. Trauma may cause subcapsular hematomas or lacerations, but not chronic atrophy with calcifications.

C. Immunocompromised patients may develop abscesses or infections but not the classic features of autosplenectomy.

D. Portal hypertension typically causes splenomegaly and varices, not atrophic and calcified spleens.

The ultrasound image demonstrates a dilated common bile duct (CBD), measuring approximately 7.7 mm in diameter. A normal CBD should generally measure less than 6 mm in a patient under 60 years old and may increase approximately 1 mm per decade thereafter or after cholecystectomy.

In the absence of gallstones within the CBD, one of the most concerning causes of CBD dilation is distal obstruction due to an extrinsic compressive lesion. The most common and clinically significant cause of distal CBD obstruction is a mass at the head of the pancreas.

A pancreatic head mass (e.g., adenocarcinoma) may compress the distal CBD and pancreatic duct simultaneously, resulting in the “double duct sign” — dilation of both the CBD and pancreatic duct. This is a classic finding in pancreatic cancer.

Comparison of answer choices:

A. Liver mass — unlikely to cause isolated CBD dilation unless invading the porta hepatis.

B. Cystic duct stone — may cause gallbladder hydrops but typically not CBD dilation unless Mirizzi syndrome is present.

C. Pancreatic head mass — Correct. This is the most likely cause of painless progressive CBD dilation without visible intraductal stones.

D. Gallbladder stones — These may be associated with biliary colic or cholecystitis but typically do not cause CBD dilation unless the stone has migrated and obstructed the distal duct.

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 left lobe of the thyroid is located anterolateral to the esophagus. On transverse ultrasound imaging, the esophagus can often be seen posterior to the left thyroid lobe as a circular structure with echogenic mucosa and hypoechoic muscular layer. The longus colli muscle lies posterior to the thyroid. The thyroid is anterior to the trachea but this refers more to the isthmus or midline portion.

According to Rumack’s Diagnostic Ultrasound:

“The esophagus is seen as a target-shaped structure posterior to the left thyroid lobe; thus, the thyroid lobe is anterolateral to the esophagus.”

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).

Annular pancreas is a congenital anomaly in which pancreatic tissue encircles the second part of the duodenum, potentially causing partial or complete duodenal obstruction (atresia). It is due to abnormal migration of the ventral pancreatic bud.

According to Rumack’s Diagnostic Ultrasound:

“Annular pancreas results from failure of the ventral pancreatic bud to rotate properly, leading to encirclement of the duodenum.”

Changing the patient's position allows evaluation of lesion mobility. Blood clots and hematomas are often mobile, while true bladder wall masses remain fixed. This technique helps differentiate between solid masses and non-adherent debris.

According to Rumack’s Diagnostic Ultrasound:

“Changing patient position may distinguish between mobile blood clots and fixed bladder wall masses.”