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

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.”

A full bladder provides an acoustic window that displaces bowel gas and distends the bladder walls, allowing optimal visualization of any bladder masses or lesions. An empty bladder may collapse, obscuring masses.

According to Rumack’s Diagnostic Ultrasound:

“Bladder evaluation should be performed with the bladder optimally distended to visualize its walls and any intraluminal masses.”

Adrenal adenomas are the most common adrenal tumors in adults. They are often discovered incidentally (adrenal incidentalomas) and are usually nonfunctioning, though some may secrete cortisol or aldosterone. Neuroblastoma is common in children, pheochromocytomas are rarer catecholamine-producing tumors, and adrenal cortical carcinoma is malignant but much less common than adenomas.

According to Rumack’s Diagnostic Ultrasound:

“Adrenal adenomas are the most common adrenal masses in adults, frequently identified incidentally on imaging studies.”

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.”

The ultrasound image shows a classic “target sign” or “donut sign,” characterized by concentric rings of alternating echogenicity. This sonographic finding is pathognomonic for intussusception, particularly when seen in the transverse plane.

Intussusception occurs when a segment of bowel telescopes into an adjacent segment, typically in children aged 6 months to 3 years. It commonly presents with intermittent abdominal pain, vomiting, and sometimes “red currant jelly” stools.

Key ultrasound features of intussusception:

Target sign in transverse view (concentric rings of bowel layers)

Pseudokidney or sandwich sign in longitudinal view

May show intraluminal mesenteric fat or vessels dragged in with the intussusceptum

Comparison of answer choices:

A. Bowel obstruction may show dilated loops of bowel with air-fluid levels and to-and-fro peristalsis but lacks the concentric ring sign.

B. Diverticulitis typically shows bowel wall thickening and pericolic fat stranding; not the concentric target appearance.

C. Appendicitis may appear as a blind-ending tubular structure (>6 mm), not with concentric ring pattern.

D. Intussusception — Correct. The image demonstrates the classic target sign seen with this condition.

De Quervain thyroiditis (subacute granulomatous thyroiditis) is often triggered by a viral infection. Patients may present with painful thyroid enlargement, elevated inflammatory markers, and transient hyperthyroidism. Hashimoto’s and Graves' diseases are autoimmune in nature.

According to Braverman’s The Thyroid:

“Subacute (De Quervain) thyroiditis typically follows a viral upper respiratory tract infection and is characterized by thyroid pain and transient thyrotoxicosis.”

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.”

The ultrasound image demonstrates a dilated duodenum with a hypoechoic soft tissue structure encircling it. This is a classic sonographic appearance suggestive of an annular pancreas. In annular pancreas, pancreatic tissue completely or partially encircles the second portion of the duodenum, which can lead to duodenal narrowing or obstruction.

Annular pancreas is a congenital anomaly that results from failure of the ventral pancreatic bud to rotate properly during embryologic development. As a result, pancreatic tissue encircles the duodenum. It may present in neonates with symptoms of duodenal obstruction or in adults with abdominal pain, pancreatitis, or vomiting.

Ultrasound Findings:

Hypoechoic pancreatic tissue encircling the duodenum

Evidence of duodenal dilatation proximal to the obstruction

“Double bubble” sign may be seen in neonates

Differentiation from other options:

A. Supernumerary kidney: Refers to an accessory kidney. It would be seen in the retroperitoneum and is unrelated to the duodenum or pancreas.

B. Pancreas divisum: A ductal anomaly best diagnosed on MRCP or ERCP. It is not typically visible on conventional ultrasound.

D. Horseshoe kidney: A renal fusion anomaly where the lower poles of the kidneys are fused. It is seen in the pelvis or lower abdomen and does not involve the duodenum or pancreas.

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 normal epididymis typically appears as a homogeneous structure that is either isoechoic or slightly hypoechoic compared to the testis. The most accurate description is "homogeneous compared to the testis," meaning the texture is uniform. It is not anechoic, nor does it typically show irregular borders unless pathology is present.

According to Rumack’s Diagnostic Ultrasound:

"The normal epididymis appears homogeneous and is isoechoic or slightly hypoechoic relative to the testis." (Rumack CM et al., Diagnostic Ultrasound, 5th ed.)