ARDMS AB-Abdomen Abdomen Sonography Examination Exam Practice Test

The spleen is suspended in the left upper quadrant by several peritoneal ligaments, including:

Lienorenal (splenorenal) ligament — attaches spleen to the left kidney.

Gastrosplenic ligament — attaches spleen to the stomach.

Phrenocolic ligament — supports the spleen inferiorly between diaphragm and colon.

These ligaments stabilize the spleen’s position while allowing some mobility.

According to Moore’s Clinically Oriented Anatomy:

“The spleen is connected to the stomach by the gastrosplenic ligament and to the posterior abdominal wall (near the left kidney) by the splenorenal (lienorenal) ligament. The phrenocolic ligament provides inferior support.”

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.”

Salivary glands are superficial structures, and high-frequency transducers (10–15 MHz) are optimal to obtain high spatial resolution. Lower frequencies are inappropriate as they lack sufficient resolution for superficial structures. A 12 MHz transducer provides excellent detail necessary for detecting small lesions, duct abnormalities, and vascular structures.

According to Rumack et al., Diagnostic Ultrasound:

"High-frequency linear transducers (10–15 MHz) are recommended for evaluating superficial structures such as salivary glands." (Rumack CM et al., Diagnostic Ultrasound, 5th ed.).

Transudative pleural effusions result from imbalances in hydrostatic and oncotic pressures, most commonly caused by congestive heart failure (CHF). In CHF, elevated hydrostatic pressure in the pulmonary capillaries leads to fluid leakage into the pleural space without significant protein or cellular content (hence, transudate). Exudative effusions (associated with infections, malignancy, and inflammation) are more often seen with pulmonary emboli, lymphoma, or empyema.

According to Light’s criteria (which differentiates transudates from exudates):

"Congestive heart failure remains the leading cause of transudative pleural effusions." (Light RW. Pleural Diseases, 6th ed.).

The ultrasound image shows a transverse view of the lower neck region at the thyroid level. The arrow is pointing to a round-to-oval structure located posterior and slightly to the left of the thyroid gland. The structure has a characteristic "target" or "bull's-eye" appearance with a hypoechoic outer ring and echogenic central mucosal interface — this is classic for the esophagus when seen in transverse view.

Key sonographic features of the esophagus:

It lies posterior to the left lobe of the thyroid.

It demonstrates a layered wall structure ("target" or "bull's-eye" appearance).

It may change shape or move during swallowing, and occasionally air bubbles or movement of fluid may be observed.

Comparison of answer choices:

A. Parathyroid glands are small, homogeneous, hypoechoic, and located posterior to the thyroid — but do not have this layered target appearance.

B. Lymph nodes have a hypoechoic cortex and echogenic hilum and are typically oval or bean-shaped, without the concentric ring appearance.

C. Esophagus — Correct. The location, appearance, and structure are consistent with the cervical esophagus.

D. Paragangliomas are highly vascular and more commonly located in the carotid body or adrenal region, not in this location or with this sonographic pattern.

The ultrasound images show a heterogeneous, solid-appearing mass within the right kidney. The patient has a history of hypertension and hematuria—classic clinical features that raise suspicion for renal cell carcinoma (RCC), especially in an adult.

Renal cell carcinoma is the most common primary malignant tumor of the kidney in adults. Common presenting symptoms include:

Hematuria (most frequent symptom)

Flank pain

Palpable abdominal mass

Hypertension (due to increased renin secretion)

Sometimes paraneoplastic syndromes (e.g., polycythemia due to erythropoietin production)

Ultrasound Features of RCC:

Solid renal mass, often with heterogeneous echotexture

May contain cystic components, calcifications, or necrotic areas

May distort the renal contour

Doppler may show internal vascularity

Differentiation from other options:

B. Adenoma: Rare and typically small, benign cortical lesions. They do not typically present with hematuria or hypertension and cannot be reliably distinguished from RCC on ultrasound.

C. Nephroblastoma (Wilms tumor): Pediatric renal tumor seen almost exclusively in children under age 5.

D. Pheochromocytoma: Arises from the adrenal gland (not the kidney); associated with hypertension but not hematuria.

The image provided is a right upper quadrant (RUQ) ultrasound—typically performed during a FAST (Focused Assessment with Sonography in Trauma) exam or for abdominal assessment. The arrow points to an anechoic (black) fluid collection seen above the diaphragm and posterior to the liver.

This fluid collection lies within the thoracic cavity, confirming the diagnosis of a pleural effusion. Pleural effusions are seen sonographically as an anechoic or hypoechoic area superior to the diaphragm in the thoracic cavity and often appear triangular or crescent-shaped. The diaphragm is visualized as a curvilinear echogenic structure separating the liver (or spleen) below from the lung space above.

Comparison of answer choices:

A. Retroperitoneal hemorrhage would be seen in the posterior abdomen, not above the diaphragm.

B. Pleural effusion is correct—anechoic fluid above the diaphragm is classic for this condition.

C. Mirror image artifact occurs when liver echoes are mirrored across the diaphragm and lung—this is not a mirror artifact.

D. Ascites collects inferior to the diaphragm and around the abdominal organs, not in the thoracic cavity.

The ultrasound images (sagittal and transverse views of the left kidney) demonstrate a large, well-defined, heterogeneous mass within the renal parenchyma. This is highly characteristic of renal cell carcinoma (RCC), the most common primary renal malignancy in adults.

Renal cell carcinoma accounts for approximately 85% of all malignant renal tumors in adults. RCC often appears as:

A solid, heterogeneous, hypoechoic to isoechoic mass within the kidney

May contain areas of necrosis or hemorrhage (seen as mixed echogenicity)

Distortion of the normal renal contour

May have internal vascularity on Doppler imaging

Clear cell carcinoma (choice B) is the most common histological subtype of RCC but is not a separate diagnosis from RCC in imaging terms. Therefore, the most accurate answer is choice C: Renal cell carcinoma.

Differentiation from other options:

A. Nephroblastoma (Wilms tumor): A pediatric renal tumor, typically seen in children under 5 years of age—not applicable in adults.

B. Clear cell carcinoma: Histological subtype of RCC, not a distinct radiologic diagnosis.

D. Transitional cell carcinoma: Arises from the renal pelvis or ureter, typically appears as a central or collecting system mass rather than a cortical/parenchymal one.

Angiomyolipomas are benign renal tumors composed of fat, smooth muscle, and blood vessels. They are strongly associated with tuberous sclerosis and may be multiple and bilateral in these patients. While RCC may occur, angiomyolipomas are much more characteristic.

According to Rumack’s Diagnostic Ultrasound:

“Angiomyolipomas are frequently multiple and bilateral in patients with tuberous sclerosis.”

The ultrasound image shows a transverse section through the upper abdomen. The arrow is pointing to a vascular structure running posterior to the pancreas and anterior to the left kidney. This vessel is the splenic vein.

Anatomically:

The splenic vein runs along the posterior border of the pancreas.

It courses medially to join the superior mesenteric vein (SMV) and form the portal vein.

It receives tributaries from the spleen, short gastric veins (draining the stomach), and the inferior mesenteric vein.

In this case, the question asks which organ is primarily drained via the vessel marked by the arrow. The splenic vein's main tributary is from the spleen.

Comparison of answer choices:

A. Spleen — Correct. The splenic vein is the primary drainage vessel for the spleen.

B. Stomach — Some gastric veins drain into the splenic vein, but the primary drainage is via left and right gastric veins into the portal system.

C. Left kidney — Drains into the left renal vein, not the splenic vein.

D. Duodenum — Drains mainly into the superior mesenteric vein (SMV).

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.

The ultrasound image shows a blind-ending, non-compressible, tubular structure in the right lower quadrant with a target or bullseye appearance in transverse section — highly suggestive of the appendix.

Sonographic features of the appendix (especially in suspected appendicitis):

Blind-ending tubular structure arising from the cecum

Non-compressible on graded compression

Diameter >6 mm is suggestive of appendicitis

May demonstrate a “target sign” in transverse view (concentric ring-like appearance)

Increased echogenicity of surrounding fat in cases of inflammation

May contain an appendicolith or show hyperemia on color Doppler if inflamed

The location (right lower quadrant) and appearance in this case are classic for the normal or potentially inflamed appendix.

Differentiation from other options:

A. Fallopian tube: Located more in the adnexal regions and usually not visible unless distended (e.g., hydrosalpinx).

B. Ureter: Usually not visualized on ultrasound unless dilated due to obstruction.

D. Jejunum: Has valvulae conniventes ("keyboard sign") and peristalsis; does not present with a blind-ending tubular appearance from the cecum.

Chronic rejection presents sonographically as cortical thinning, decreased renal size, and increased echogenicity of the renal sinus fat. Acute rejection typically causes an enlarged, edematous kidney with increased parenchymal echogenicity but preserved size early on.

According to Zwiebel’s Introduction to Vascular Ultrasound:

“In chronic rejection, the allograft becomes smaller with cortical thinning, increased echogenicity, and prominence of the central sinus fat.”

The ultrasound image demonstrates a fluid-filled structure in the posterior knee region, consistent with a Baker cyst (also called a popliteal cyst). A Baker cyst is a synovial fluid-filled sac arising from the posterior medial aspect of the knee joint, typically extending between the medial head of the gastrocnemius and the semimembranosus tendon.

The history of delayed-onset claudication (pain in the calf when walking) two weeks after this image was obtained is strongly suggestive of a ruptured Baker cyst. When a Baker cyst ruptures, synovial fluid may track inferiorly into the calf, producing pain, swelling, and clinical symptoms that mimic deep vein thrombosis (DVT) or arterial insufficiency (e.g., pseudothrombophlebitis syndrome).

Ultrasound findings consistent with a ruptured Baker cyst:

Complex fluid collection tracking along muscle fascial planes (hypoechoic to anechoic)

Posterior calf swelling and tenderness

Absence of thrombus in the deep venous system

Crescent-shaped fluid may be seen between muscle compartments

Why the other choices are incorrect:

A. Neuropathy: Would not show fluid-filled structures on ultrasound and would not present with calf swelling.

B. Infected hematoma: May appear complex, but would require a history of trauma or anticoagulation and systemic signs (fever, redness).

C. Thrombophlebitis: Involves a thrombosed superficial vein with wall thickening and surrounding inflammation, which is not seen in this image.

Type I choledochal cyst, characterized by fusiform dilatation of the common bile duct, is the most common form, accounting for 80-90% of cases. Other types are much less frequent.

According to Rumack’s Diagnostic Ultrasound:

“Type I fusiform dilatation of the extrahepatic bile duct is the most common type of choledochal cyst.”

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.

Malignant lymph nodes are often round in shape (short axis/long axis ratio approaches 1), while benign lymph nodes are typically oval (short axis/long axis ratio < 0.5). Rounded shape in post-thyroidectomy patients raises suspicion for metastatic disease.

According to AIUM and ACR Thyroid Imaging Guidelines:

“A rounded lymph node shape is suspicious for malignancy, especially in patients with thyroid cancer.”

The ultrasound image shows the liver in a transverse view with the arrow pointing to the middle hepatic vein (MHV). The MHV is a key sonographic landmark that anatomically divides the right and left lobes of the liver.

According to Couinaud's segmental anatomy, which is the basis for surgical and radiological liver segmentation:

The middle hepatic vein runs within the main lobar fissure.

It separates the right lobe (segments V–VIII) from the left lobe (segments II–IV).

This division is crucial in liver surgery and interventional procedures.

Comparison of answer choices:

A. Right anterior and posterior segments are divided by the right hepatic vein, not the middle hepatic vein.

B. Right and left lobes — Correct. The middle hepatic vein, shown by the arrow, defines this boundary.

C. Left medial and lateral segments are divided by the left hepatic vein or falciform ligament.

D. Left superior and inferior is not a standard anatomic division in liver segmentation.

Acute pyelonephritis is a bacterial infection of the renal parenchyma and collecting system. Classic clinical findings include fever, flank pain, leukocytosis (elevated white blood cells), and pyuria (white blood cells in urine). Ultrasound may demonstrate renal enlargement, decreased echogenicity, and loss of corticomedullary differentiation.

Nephrocalcinosis (A) involves calcium deposition without infection.

Staghorn calculus (B) may lead to infection but is primarily characterized by obstructive uropathy.

Renal cell carcinoma (C) presents with hematuria and mass formation rather than infection symptoms.

Reference Extracts:

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

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

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When the sample volume (gate) is too large, it captures signals from both the vessel and surrounding tissues or adjacent flows. This leads to a broadening of the spectral waveform and produces "spectral noise" or "spectral broadening," reducing the accuracy of velocity measurements and waveform analysis. Aliasing results from high velocity relative to the Nyquist limit, not from gate size.

According to Zwiebel’s Introduction to Vascular Ultrasound:

“Increasing the sample volume beyond the vessel size causes spectral broadening, resulting in spectral noise and inaccurate Doppler measurements.”

An abdominal aortic aneurysm (AAA) measuring ≥5.5 cm represents a significantly increased risk of rupture and often requires surgical evaluation. The sonographer must report this critical finding immediately to the interpreting physician. The sonographer should never disclose a diagnosis directly to the patient.

According to AIUM and SRU Guidelines:

“An aortic diameter of 5.5 cm or greater should be promptly reported to the interpreting physician due to the high risk of rupture.”

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 demonstrates bowel loops with peristalsis visualized within the inguinal canal, which is diagnostic of an inguinal hernia—more specifically, an indirect inguinal hernia. Indirect hernias pass through the deep inguinal ring and may extend into the scrotum, appearing sonographically as bowel-containing masses adjacent to or within the scrotal sac. Peristaltic motion confirms the presence of viable bowel content.

This finding is typical in indirect inguinal hernias, which are more common in males and often congenital due to a patent processus vaginalis. The herniated bowel can be traced through the inguinal canal, as seen in this image.

Comparison of answer choices:

A. Hematocele presents as a complex fluid collection surrounding the testis, often due to trauma—no complex fluid or trauma is apparent here.

B. Testicular rupture shows discontinuity of the tunica albuginea and irregular testicular contour—none of which is seen.

C. Orchiectomy would show an absent testis—this is not the case here.

D. Indirect hernia is correct. The presence of bowel with peristalsis in the inguinal canal is diagnostic.

Downstream from a significant renal artery stenosis, the acceleration time is prolonged due to delayed systolic upstroke (“tardus-parvus waveform”). This is a sensitive Doppler parameter for detecting hemodynamically significant stenosis. Spectral broadening usually occurs at the stenotic site, not distal to it.

According to Zwiebel’s Introduction to Vascular Ultrasound:

“Prolonged acceleration time and reduced acceleration index characterize tardus-parvus waveforms distal to renal artery stenosis.”

The ultrasound image reveals a well-defined, anechoic (black), thin-walled fluid collection located in the subcutaneous or parenchymal plane of the breast. This is most consistent with a seroma, particularly in the context of recent breast surgery.

A seroma is a common postsurgical finding, representing a sterile collection of serous fluid that accumulates in the surgical bed. It typically appears:

Anechoic (or hypoechoic if older)

Well circumscribed

Without internal septations or debris

Lacking hyperemia or surrounding inflammatory changes

This contrasts with:

A. Carcinoma — typically presents as an irregular, hypoechoic mass with angular margins, internal vascularity, and shadowing.

B. Blood clot (hematoma) — often appears heterogeneous, with internal echoes and variable echotexture depending on the age of the clot.

C. Abscess — appears as a complex fluid collection with thick walls, internal debris, septations, and surrounding hyperemia (often with clinical signs of infection).

D. Seroma — Correct. The described anechoic, clean-walled fluid collection is classic for a postoperative seroma.

The arrow in this Doppler ultrasound image of the kidney is pointing to vessels located at the corticomedullary junction, arching over the bases of the medullary pyramids. This vascular pattern is characteristic of the arcuate arteries.

Renal arterial anatomy follows a specific branching hierarchy:

Segmental arteries branch off the main renal artery.

Interlobar arteries travel between renal pyramids.

Arcuate arteries arch over the base of the pyramids at the corticomedullary junction.

Interlobular arteries extend into the cortex from the arcuate arteries.

Key characteristics of arcuate arteries on ultrasound:

Located at the corticomedullary junction (between the medullary pyramids and renal cortex).

Run perpendicular to the long axis of the kidney, often forming an arching or curving pattern.

Commonly targeted in Doppler studies to assess resistive index (RI) in renal perfusion studies.

Comparison of answer choices:

A. Interlobular arteries are smaller vessels that extend perpendicularly from the arcuate arteries into the cortex—not visible at this level.

B. Arcuate — Correct. The arrow is indicating these vessels arching over the medullary pyramids.

C. Segmental arteries are larger and deeper, branching off the renal artery near the hilum.

D. Interlobar arteries course between the pyramids but do not arch along their base.

The image shows a small hepatic lesion located very close to the anterior liver capsule, as indicated by the arrow. When imaging very superficial or near-field structures like subcapsular hepatic lesions, using a standoff pad is the most effective technique for optimizing visualization.

A standoff pad (also known as an acoustic stand-off or gel pad) helps increase the distance between the transducer and the superficial target. This improves the focus and beam shape for near-field imaging and minimizes reverberation and ring-down artifacts. It allows better evaluation of superficial lesions by positioning them within the focal zone of the transducer, which is usually set a few millimeters below the probe surface.

Differentiation from other options:

A. Decrease depth: While reducing depth can help center deeper lesions in the field of view, it does not address issues with near-field resolution.

B. Scan in upright position: This may help in gallbladder or fluid positioning but is not optimal for improving visualization of superficial liver lesions.

C. Move the transducer focus: Adjusting focus deeper into the image won't enhance resolution of very superficial structures unless a standoff is used to bring the lesion into the focal zone.

The image demonstrates a characteristic "central dot sign" — a hallmark finding of Caroli disease. This is best appreciated on ultrasound as a cystic dilation of the intrahepatic bile ducts with a central echogenic dot or linear structure (which corresponds to the portal vein and fibrous tissue within the dilated duct). The arrow in the image points to one such dilated duct.

Caroli disease is a rare congenital disorder characterized by segmental, saccular dilation of intrahepatic bile ducts. It is often associated with congenital hepatic fibrosis and may predispose to cholangitis, stone formation, and even cholangiocarcinoma.

Key ultrasound features of Caroli disease:

Cystic or saccular dilations of the intrahepatic bile ducts

The "central dot sign" — echogenic focus in the center of the dilated ducts (representing portal vein radicle or fibrous tissue)

May show associated hepatosplenomegaly or signs of portal hypertension

Differentiation from other options:

A. Sclerosing cholangitis: Typically causes diffuse or segmental biliary ductal wall thickening and stricturing; does not present with cystic dilations.

B. Alagille syndrome: A multisystem disorder often characterized by a paucity of intrahepatic bile ducts, not dilation.

D. Biliary atresia: Presents in infancy with obliteration of extrahepatic bile ducts, echogenic "triangular cord" sign, and absence of a visible gallbladder. It does not cause ductal dilation.

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.”

The main pancreatic duct (duct of Wirsung) runs through the central portion of the pancreas, medial and slightly posterior to the superior mesenteric vein (SMV). It converges with the common bile duct near the ampulla of Vater.

According to Moore’s Clinically Oriented Anatomy:

“The main pancreatic duct runs centrally within the gland and lies medial to the superior mesenteric vein.”

The spleen lies in the left hypochondrium, superior and lateral to the fundus of the stomach, and directly contacts the diaphragm. It occupies the space between the stomach and diaphragm. The liver and kidneys are located more medially or inferiorly.

According to Gray’s Anatomy for Students:

“The spleen lies posterolateral to the fundus of the stomach, separated from the diaphragm by its fibrous capsule.”

An accessory spleen (splenule) is a congenital variant, commonly located near the splenic hilum, and has identical echogenicity to the native spleen. This finding is benign and often incidental.

According to Rumack’s Diagnostic Ultrasound:

“Accessory spleens are typically found near the splenic hilum and are isoechoic to the normal splenic parenchyma.”

The ultrasound image demonstrates a transverse view of the abdominal vasculature, where the arrow is pointing to a circular vascular structure anterior to the aorta and posterior to the body of the pancreas — consistent with the superior mesenteric artery (SMA).

The SMA originates from the anterior aspect of the abdominal aorta just below the level of the celiac trunk and courses anterior to the left renal vein and uncinate process of the pancreas. On transverse ultrasound, it is often seen in cross-section as a round, pulsatile structure with echogenic walls, situated just anterior to the aorta. This appearance is known as the “target sign” or “bull's-eye” appearance.

Vessel Position Landmarks (transverse plane):

Aorta: Posterior and central

SMA: Just anterior to the aorta

Left renal vein: Passes between the aorta and SMA (nutcracker location)

Right renal artery: Courses posterior to the IVC toward the right kidney

Differentiation from other options:

A. Proper hepatic artery: Typically visualized within the liver hilum (portal triad), not in this anatomic location.

C. Left renal vein: Seen in transverse as a longer, oval structure crossing anterior to the aorta and posterior to the SMA.

D. Right renal artery: Arises laterally from the aorta and courses posterior to the IVC — not visualized in this axial midline location.

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 ultrasound image clearly demonstrates a thickened and elongated pyloric muscle with a visible channel, which is characteristic of hypertrophic pyloric stenosis (HPS). This condition is most commonly seen in male infants between 2 and 8 weeks of age who present with non-bilious projectile vomiting, dehydration, and a palpable “olive-like” mass in the right upper quadrant.

Ultrasound is the imaging modality of choice and is highly sensitive and specific for diagnosing pyloric stenosis.

Key sonographic criteria for HPS:

Muscle thickness >3 mm

Pyloric channel length >15–17 mm

“Target sign” or “doughnut sign” on transverse imaging (concentric rings)

“Cervix” or “railroad track sign” on longitudinal imaging (elongated canal with echogenic center)

Differentiation from other options:

A. Intussusception: Also shows a target sign, but it occurs in the right lower quadrant or periumbilical region, not in the gastric antrum.

C. Hydronephrosis: Refers to dilation of the renal pelvis and calyces — not gastrointestinal.

D. Gastritis: May show gastric wall thickening but lacks the distinct elongated, thickened pyloric muscle seen here.

Hepatitis A is primarily transmitted via the fecal-oral route, often through contaminated food or water. Hepatitis B, C, and D are transmitted through blood and body fluids.

According to CDC and WHO guidelines:

“Hepatitis A virus (HAV) is transmitted primarily by the fecal-oral route via ingestion of contaminated food or water.”

Nutcracker syndrome results from compression of the left renal vein between the superior mesenteric artery (SMA) and the aorta. This can cause hematuria, flank pain, and pelvic congestion due to impaired venous drainage.

According to Zwiebel’s Introduction to Vascular Ultrasound:

“In nutcracker syndrome, the left renal vein is compressed between the aorta and SMA, resulting in venous hypertension.”

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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Postsurgical breast scarring may appear hypoechoic and irregular but typically shows no internal vascularity on Doppler imaging. In contrast, recurrent tumors generally exhibit increased internal vascular flow due to neovascularization. Therefore, absent Doppler signal helps suggest scar tissue rather than malignancy.

According to Stavros’ Breast Ultrasound:

“The absence of internal Doppler flow favors scar tissue, whereas recurrent malignancy typically demonstrates internal vascularity.”

A complex pleural effusion often contains internal septations or fibrin strands, distinguishing it from simple anechoic effusion. These septations suggest exudative processes such as infection, malignancy, or hemothorax.

According to Rumack’s Diagnostic Ultrasound:

“Complex pleural effusions demonstrate internal septations or loculations, often related to infection or malignancy.”

A common bile duct (CBD) measuring up to 5 mm is considered normal in most patients under age 60. Some references allow for up to 6 mm, especially post-cholecystectomy or in older individuals. Significant dilation (suggestive of obstruction) typically exceeds these measurements.

According to Rumack’s Diagnostic Ultrasound:

“The normal common bile duct measures up to 5–6 mm, with slight increases considered normal after cholecystectomy or with advancing age.”

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.”

Urinomas are collections of urine in the retroperitoneum that result from trauma, surgery, or obstruction causing urine leakage. Trauma is a frequent cause of urinoma formation due to disruption of the urinary tract.

According to Rumack’s Diagnostic Ultrasound:

“Urinomas may develop as a complication of trauma, surgery, or obstructive uropathy with urinary extravasation into the retroperitoneum.”

The ultrasound image shown is a transverse endorectal (transrectal) ultrasound, commonly used to evaluate the prostate and adjacent structures. The two hypoechoic (dark) oval-shaped structures seen superior and posterior to the prostate are characteristic of the seminal vesicles.

The seminal vesicles are paired, elongated glands located superior and posterior to the base of the prostate and are best visualized in transverse planes on endorectal imaging. They appear as hypoechoic or anechoic structures with internal septations, depending on the degree of fluid content.

In contrast:

The urethra appears as a central echogenic linear structure within the prostate.

The prostate base is more inferior in the scan and is visualized just above the urethra.

The ejaculatory ducts are usually not as prominently visualized and are located medial to the seminal vesicles, entering the prostate near the verumontanum.

This image most clearly demonstrates the bilateral seminal vesicles.

The mucosa is the innermost layer of the gastrointestinal wall, consisting of epithelium, lamina propria, and muscularis mucosae. It is responsible for absorption and secretion. The submucosa lies just outside the mucosa.

According to Moore’s Clinically Oriented Anatomy:

“The mucosa is the innermost layer of the gastrointestinal tract, responsible for nutrient absorption and secretion.”

The sonographic image shows a complex fluid collection within the liver parenchyma, with internal echoes and possibly septations, consistent with an abscess. In the clinical context of post-procedural fever following a liver biopsy, a liver abscess is the most likely diagnosis.

A liver abscess appears on ultrasound as a hypoechoic or complex fluid collection that may contain internal debris, septations, or gas (which may produce reverberation artifacts). These features distinguish it from other post-procedural complications.

A cyst (Option A) typically appears as an anechoic, well-defined lesion with posterior acoustic enhancement and no internal debris—this does not match the image or clinical setting.

A biloma (Option B) is a bile collection that can appear similar to a cyst or fluid collection but typically occurs due to bile leak; however, fever and internal complexity on ultrasound more strongly suggest abscess.

A hematoma (Option D) may also appear complex but usually presents with pain and not fever unless secondarily infected. Over time, hematomas evolve in appearance but lack septations and gas unless superinfected.

The correct sequence of renal arterial branching is: renal artery → segmental arteries → interlobar arteries → arcuate arteries → interlobular arteries. This branching pattern is important for understanding renal perfusion and evaluating vascular disorders.

According to Moore’s Clinically Oriented Anatomy:

“Renal arteries divide into segmental branches, which give rise to interlobar arteries, then arcuate arteries, and finally interlobular arteries.”

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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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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