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

The ultrasound image shows an anechoic (black) fluid collection in the perihepatic and perirenal spaces. The fluid outlines the liver (LIV) and right kidney (RK), which is characteristic of free fluid in the peritoneal cavity — consistent with ascites.

Sonographic features of ascites:

Anechoic (or hypoechoic) fluid in dependent areas of the abdomen

Seen surrounding the liver, spleen, and intestines

Can be free-flowing or loculated

Bowel loops may be floating or displaced centrally

This image is consistent with a typical finding of ascites: free fluid in Morison’s pouch (hepatorenal recess), a common site for fluid accumulation.

Differentiation from other options:

A. Hydropic gallbladder: Refers to an enlarged gallbladder filled with clear bile; not visible in this image.

B. Hemoperitoneum: May appear similar to ascites, but usually has complex echogenicity or layering if acute; clinical context (trauma, bleeding) is essential for diagnosis.

C. Bowel obstruction: Would show dilated, fluid-filled bowel loops with peristalsis or to-and-fro motion, not evident here.

Testicular metastases are rare and usually identified in older patients. The most frequent primary site of malignancies metastasizing to the testes is theprostate. Studies (Ulbright and Young, 2008; Mosharafa et al., 2003) indicate that prostatic adenocarcinoma accounts for the highest number of testicular metastases, with lung and gastrointestinal tract malignancies also contributing less frequently. These metastases can be unilateral or bilateral and are often discovered incidentally during surgical intervention for prostate cancer.

The metastatic route involves retrograde venous extension, arterial embolism, or lymphatic dissemination. Histologically, prostatic adenocarcinoma in the testis can be confirmed viaimmunohistochemical markers like prostate-specific antigen (PSA), supporting its prostatic origin.

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.

D. Occlusion: Would appear as a lack of flow with thrombus or echogenic content filling the lumen, not dilation.

The ultrasound image shows a hypoechoic, round structure with internal microcalcifications — hallmarks of recurrent papillary thyroid carcinoma (PTC) metastasis in a lymph node.

Key sonographic features supporting recurrent papillary thyroid cancer:

Hypoechoic round lymph node (loss of normal oval shape and hilum)

Microcalcifications (punctate echogenic foci) – highly suggestive of metastatic PTC

Abnormal morphology (loss of fatty hilum, rounded shape, increased vascularity if Doppler used)

Seen in the thyroid bed or lateral neck post-thyroidectomy

Why the other options are incorrect:

B. Normal postsurgical lymph node – Would be oval with echogenic hilum and no microcalcifications

C. Residual glandular tissue – Would have a more homogeneous echotexture similar to thyroid tissue and be located at the thyroid bed, not necessarily nodal

D. Reactive lymph node – May be enlarged but retain a normal hilum and vascular pattern, and lack microcalcifications

The main renal vein should be assessed in addition to the renal arteries during renal Doppler exams. Venous thrombosis may coexist with arterial abnormalities and can impact renal perfusion. Evaluation of both arterial inflow and venous outflow ensures a comprehensive assessment of renal vascular patency.

According to Zwiebel’s Introduction to Vascular Ultrasound:

“Renal vein assessment should be performed during renal artery Doppler studies to exclude venous thrombosis or outflow obstruction.”

A thyroglossal duct cyst is the most common congenital cystic anomaly in the anterior midline neck. It arises from persistent remnants of the thyroglossal duct, typically located inferior to the hyoid bone.

According to Rumack’s Diagnostic Ultrasound:

“Thyroglossal duct cysts are located in the midline anterior neck and are the most common congenital cystic neck lesions.”

The ultrasound image shows a classic longitudinal view of a markedly thickened pyloric muscle with an elongated pyloric channel. This finding is consistent with hypertrophic pyloric stenosis (HPS), a condition most commonly seen in male infants between 2 and 8 weeks of age.

The most characteristic clinical finding associated with HPS is an “olive-shaped” palpable mass in the right upper quadrant or epigastric region, which represents the hypertrophied pylorus.

Clinical presentation of HPS includes:

Non-bilious projectile vomiting (due to gastric outlet obstruction)

Dehydration and weight loss

A palpable “olive” mass on physical exam

Visible peristalsis may be noted on the abdominal wall

Sonographic diagnostic criteria for HPS:

Pyloric muscle thickness ≥ 3 mm

Pyloric channel length ≥ 15–17 mm

“Cervix sign” or “target sign” (transverse view)

Failure of gastric contents to pass through the pylorus on real-time imaging

Differentiation from other options:

B. Fever of unknown origin: Not characteristic of HPS.

C. Red currant jelly stools: Classic for intussusception.

D. Bilious vomiting: Seen in distal duodenal or jejunal obstruction, not in pyloric stenosis (vomiting is non-bilious in HPS).

A varicocele is an abnormal dilatation of the pampiniform plexus veins, usually seen on the left side due to the perpendicular insertion of the left testicular vein into the left renal vein, making it more susceptible to elevated venous pressure. Sonographically, varicoceles appear as multiple serpiginous anechoic tubular structures that show venous flow on color Doppler, often accentuated with Valsalva maneuver.

Hydrocele (A) is a fluid collection surrounding the testis.

Hematocele (C) is blood within the tunica vaginalis.

Spermatocele (D) is a cystic lesion arising from the epididymis.

Reference Extracts:

Dogra VS, Bhatt S. "Sonographic evaluation of testicular varicoceles." Journal of Ultrasound in Medicine. 2004;23(6): 829-838.

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

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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.

Addison disease (primary adrenal insufficiency) results in insufficient production of cortisol and aldosterone. The hallmark laboratory findings include:

Hyponatremia (low sodium)

Hyperkalemia (high potassium)

Elevated liver enzymes (due to nonspecific hepatic involvement)

Fatigue, weight loss, and hypotension are common clinical features.

Conn syndrome (B) causes hyperaldosteronism, leading to hypokalemia (not hyperkalemia).

Acute pancreatitis (C) would typically show elevated amylase/lipase.

Hepatocellular carcinoma (D) may present with elevated liver enzymes but not the electrolyte pattern described.

Reference Extracts:

Nieman LK. "Diagnosis and Treatment of Primary Adrenal Insufficiency." J Clin Endocrinol Metab. 2011;96(7):1957-1966.

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

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