AB-Abdomen Abdomen Sonography Examination Questions and Answers

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 renal arteries originate from the abdominal aorta just inferior to the superior mesenteric artery (SMA). The SMA arises anteriorly from the abdominal aorta at the level of L1, and just below it, the renal arteries branch laterally. The splenic vein, portal vein, and hepatic artery are located more superiorly in relation to the renal arteries.

According to Moore's Clinically Oriented Anatomy:

"The superior mesenteric artery arises from the anterior surface of the abdominal aorta just above the renal arteries." (Moore KL et al., Clinically Oriented Anatomy, 8th ed.)

Thyroid adenomas typically present as well-defined nodules surrounded by a thin, hypoechoic peripheral halo representing compressed thyroid parenchyma or fibrous capsule. Irregular margins suggest malignancy.

According to Rumack’s Diagnostic Ultrasound:

“A thin hypoechoic halo is characteristic of benign thyroid adenomas.”

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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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.

Ring-down artifact occurs when gas bubbles resonate or oscillate, creating continuous echoes distal to the structure that appear as a vertical, echogenic band extending posteriorly. This is distinct from reverberation, which produces multiple discrete reflections.

According to Zwiebel’s Introduction to Vascular Ultrasound:

“Ring-down artifact results from resonance of gas bubbles, producing a continuous, echogenic tail distal to the reflecting interface.”

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.

The sonographic images depict an acute thrombotic process involving the portal venous system. The absence of cavernous transformation in the setting of portal vein thrombus indicates that the process is acute. In chronic portal vein thrombosis, collateral vessels form in the porta hepatis to bypass the obstruction, a process known as cavernous transformation.

Sonographic features suggesting acute portal vein thrombosis:

Echogenic thrombus within the portal vein lumen

Absence of flow on color Doppler

Enlarged portal vein diameter early in the process

No evidence of cavernous transformation (i.e., no serpiginous collateral vessels at porta hepatis)

Cavernous transformation is a hallmark of chronic portal vein thrombosis and takes weeks to months to develop. Therefore, its absence on ultrasound supports an acute diagnosis.

Differentiation from other options:

A. Free fluid: Non-specific and may or may not be present in hepatic vascular thrombosis.

B. Ductal dilatation: Related to biliary obstruction, not portal or hepatic venous thrombosis.

C. Hepatic vein thrombosis: Seen in Budd-Chiari syndrome, which affects hepatic outflow, not portal inflow.

The ultrasound image provided shows the liver and diaphragm imaged in a coronal plane with characteristic rib shadows and costophrenic angles. The orientation of the image and the structures visualized suggest that the transducer is placed in the right mid-axillary line, with the sound beam directed coronally — this is a classic right coronal scanning approach.

Key features supporting this:

The liver appears superiorly in the image.

Multiple echogenic lines (representing the ribs) run obliquely, casting acoustic shadows.

The diaphragm and adjacent lung base are seen clearly, which is commonly imaged through the right intercostal spaces in a coronal plane.

Comparison of answer choices:

A. Anterior: Would show a more transverse view of the liver and not typically image the diaphragm and lung this way.

B. Posterior: Not used for upper abdominal scanning due to shadowing from the spine and posterior ribs.

C. Left coronal: Would show the spleen and left kidney — not the liver as seen here.

D. Right coronal — Correct. This image was obtained using the right coronal (intercostal) approach through the right flank.

The ultrasound image demonstrates diffuse increased echogenicity of the liver parenchyma with posterior beam attenuation (acoustic shadowing), findings that are consistent with hepatic steatosis (fatty liver disease). The liver appears brighter than normal, and the vascular markings, particularly of the portal veins, are obscured due to the increased parenchymal echogenicity.

Hepatic steatosis refers to the abnormal accumulation of fat within hepatocytes and is commonly associated with obesity, diabetes, alcohol use, and metabolic syndrome.

Classic sonographic features of hepatic steatosis include:

Diffuse hyperechogenicity (“bright liver”)

Poor visualization of intrahepatic vessels and diaphragm

Posterior acoustic attenuation

Increased hepatic echogenicity relative to the renal cortex

Differentiation from other options:

A. Acute hepatitis: Usually presents with normal or slightly decreased echogenicity, "starry sky" appearance due to prominent portal triads and periportal edema.

C. Medullary sponge kidney: A renal condition with echogenic medullary pyramids, not hepatic.

D. Acute medical renal disease: Affects the kidneys, often with bilateral renal enlargement and increased cortical echogenicity—again not related to liver imaging.

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.”

The Doppler spectral waveform shown in this image of the right testis demonstrates low-resistance, forward-flowing arterial waveforms with continuous diastolic flow — this is characteristic of normal testicular perfusion. The presence of both color Doppler flow and a resistive index (RI) of 0.66 further supports normal testicular arterial circulation.

Key Doppler features of a normal testicular waveform:

Low-resistance waveform (RI typically 0.5–0.75)

Continuous diastolic flow

No reversal of flow or spectral broadening

Color Doppler confirms uniform intratesticular vascularity

Clinical context:

Normal testicular flow on Doppler imaging excludes testicular torsion, infarction, or significant inflammation.

Testicular torsion would show either absent or very high-resistance (reduced or absent diastolic flow) waveform.

Epididymo-orchitis may show hyperemia with low resistance but often presents with other gray-scale findings like heterogeneous echotexture or scrotal wall thickening.

Differentiation from other options:

B. Increased resistance: RI >0.75 and reduced or reversed diastolic flow; may indicate impending torsion or ischemia.

C. Tardus parvus: A slow systolic upstroke and diminished amplitude; indicates proximal arterial stenosis.

D. Triphasic: Normal waveform in peripheral arteries, such as extremities, not seen in testicular circulation.

Patients with liver disease often have coagulopathy due to impaired synthesis of clotting factors. This places them at greater risk for bleeding or hematoma formation after biopsy. While hypertension may increase bleeding risk slightly, liver disease presents a significantly higher risk due to impaired coagulation.

According to the Society of Interventional Radiology (SIR) guidelines:

“Liver dysfunction is a significant risk factor for post-biopsy hemorrhage due to associated coagulopathy.”

The celiac trunk arises from the abdominal aorta and immediately divides into three primary branches:

Left gastric artery

Common hepatic artery

Splenic artery

The proper hepatic and gastroduodenal arteries are secondary branches of the common hepatic artery.

According to Moore’s Clinically Oriented Anatomy:

“The celiac trunk trifurcates into the left gastric, common hepatic, and splenic arteries.”

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.”

Pancreas divisum occurs when the dorsal and ventral pancreatic ducts fail to fuse during embryologic development. This results in most pancreatic secretions draining through the minor papilla via the dorsal duct (duct of Santorini).

According to Rumack’s Diagnostic Ultrasound:

“In pancreas divisum, the dorsal and ventral pancreatic ducts fail to fuse, resulting in separate drainage systems.”

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).

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.”

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.”

A wandering spleen occurs when the spleen is not adequately anchored by its supporting ligaments, allowing it to move freely within the abdomen. This increases the risk of splenic torsion, which compromises vascular supply and may result in infarction if not corrected.

According to Rumack’s Diagnostic Ultrasound:

“The most serious complication of a wandering spleen is torsion, which may result in splenic infarction.”

The ultrasound image of the thyroid clearly shows posterior shadowing originating from the lateral edges of a rounded structure, which is indicative of edge shadow artifact. Edge shadowing occurs when an ultrasound beam passes tangentially to a rounded or curved structure, such as a cyst or blood vessel. The difference in sound wave refraction and beam divergence at the edges leads to decreased echo signals deep to the edges, creating linear hypoechoic bands — which is exactly what the arrows are pointing to in the image.

Edge shadow artifact is purely a result of beam physics and not a real anatomic or pathologic finding.

Key characteristics of edge shadowing:

Appears as a narrow, linear hypoechoic (dark) shadow extending deep to the edge of a curved interface (e.g., cyst, vessel, thyroid nodule)

Caused by refraction and beam deflection, leading to reduced beam intensity distal to the edges

Most commonly seen adjacent to cysts or fluid-filled structures

Differentiation from other options:

A. Focal enhancement: Appears as increased echogenicity distal to a fluid-filled structure due to lower attenuation of the sound beam through fluid (opposite of shadowing).

C. Speed error: A less common artifact that results in displacement of structures due to variation in assumed sound speed.

D. Comet tail: A reverberation artifact that appears as a series of closely spaced bright echoes, often associated with metallic objects or cholesterol crystals in adenomyomatosis.

The ultrasound image labeled “SAG LT KIDNEY MID” demonstrates a left kidney with two separate, centrally located echogenic renal sinuses separated by intervening renal parenchyma. This appearance is classic for a duplicated collecting system.

A duplicated collecting system (also known as duplex kidney) is a congenital anomaly in which a single kidney contains two separate pelvicalyceal systems. It may be complete (with two ureters) or incomplete (partial duplication of ureters). This condition is one of the most common congenital anomalies of the urinary tract.

Sonographic Features of a Duplicated Collecting System:

Two separate central echogenic renal sinus regions seen within one kidney

Intervening parenchyma between the two sinuses

May show associated findings: hydroureteronephrosis (especially of upper pole moiety), ureterocele

Best visualized in sagittal plane

Differentiation from other options:

A. Horseshoe kidney: Shows fusion of the lower poles of the kidneys, typically located anterior to the aorta in the midline—not demonstrated here.

B. Crossed renal ectopia: One kidney is located on the opposite side of the body; this image shows a normally positioned kidney.

C. Prominent renal column (column of Bertin): May mimic a mass, but does not produce two separate sinuses as shown here.

When measuring the abdominal aorta (or any vessel diameter for aneurysm evaluation), calipers should be placed from outer wall to outer wall to ensure inclusion of the full vessel diameter, including any mural thrombus. This is the standard method accepted by professional societies.

According to AIUM and SRU Guidelines:

“Vessel diameter measurements should be performed from outer wall to outer wall to avoid underestimation of aneurysm size.”

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 tunica albuginea is a dense fibrous capsule surrounding the testis. Discontinuity of the tunica albuginea on ultrasound is diagnostic of testicular rupture — a urologic emergency that requires immediate surgical repair to preserve testicular function and viability. Early surgical intervention within 72 hours has a high success rate for testicular salvage (up to 90%).

Intratesticular hematoma (A) may be managed conservatively if the tunica albuginea is intact.

Heterogeneity of the parenchyma (C) indicates injury but not necessarily rupture.

Increased vascularity (D) may be seen with inflammation or reperfusion but does not mandate surgery unless rupture is present.

Reference Extracts:

Dogra VS, Bhatt S. "Acute painful scrotum: ultrasound evaluation." Radiologic Clinics of North America. 2004; 42(2):349-363.

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

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The ultrasound image shows a sagittal view of the right kidney with multiple anechoic (black), non-communicating cysts of varying sizes distributed throughout the renal parenchyma, consistent with autosomal dominant polycystic kidney disease (ADPKD).

ADPKD is a hereditary disorder characterized by the progressive development of multiple bilateral renal cysts, which leads to renal enlargement and eventual loss of function. This condition typically affects both kidneys, making bilateral polycystic involvement expected. Therefore, the same cystic appearance is anticipated in the contralateral (left) kidney as well.

Comparison of answer choices:

A. Duplicated collecting system: This is a congenital anomaly but does not result in diffusely cystic kidneys.

B. Polycystic kidney: Correct. Bilateral renal involvement is the hallmark of ADPKD.

C. Parapelvic cysts: These are simple cysts located in the renal sinus and do not exhibit the diffuse pattern seen here.

D. Atrophic kidney: Not typical in the contralateral side in ADPKD; the disease affects both kidneys symmetrically.

A tumor (such as cholangiocarcinoma, pancreatic head carcinoma, or metastases) is a common cause of biliary duct obstruction. It can compress or invade the bile ducts, leading to intrahepatic and extrahepatic duct dilatation.

Cholecystitis (B) typically affects the gallbladder but may rarely cause duct obstruction if complicated.

Pneumobilia (C) refers to air in the biliary tree, not obstruction.

Hepatitis (D) causes liver inflammation but not mechanical biliary obstruction.

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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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 structure indicated by the arrow in the ultrasound image is the adrenal gland. On ultrasound, the adrenal gland in neonates and infants is relatively large and has a distinctive “Y” or “V” shape in the transverse view. It is located superior and slightly medial to the upper pole of the kidney.

In this image, the arrow is pointing to a hypoechoic, curved structure with a thin echogenic central stripe, representing the fetal adrenal gland. This echogenic stripe corresponds to the adrenal medulla, while the surrounding hypoechoic area represents the cortex.

Differential features:

A. Kidney: While the kidney is visualized posterior to the adrenal gland and shows a reniform shape with a central echogenic sinus and peripheral cortex, it is not the structure being directly pointed to by the arrow.

B. Bowel loop: Bowel has variable echogenicity with peristalsis and shadowing from air. It does not have the consistent morphology or location seen in the image.

C. Diaphragm: Appears as a thin, hyperechoic linear structure separating the thoracic cavity from the abdomen. It is seen more superiorly than the indicated structure and lacks the “Y” or “V” adrenal configuration.

Key Anatomical Landmarks:

The adrenal glands are located in the retroperitoneum, superior to the kidneys, and appear prominent on ultrasound in neonates.

In transverse view, the right adrenal gland is anterior to the crus of the diaphragm and posterior to the inferior vena cava (IVC).

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 seminiferous tubules are coiled structures located within the testes where spermatogenesis (sperm production) occurs. They are surrounded by Sertoli and Leydig cells that support spermatogenesis and testosterone production.

Gubernacula (A) are fetal structures involved in testicular descent.

Efferent ductules (B) connect the rete testis to the epididymis but are not located within the testicular parenchyma.

Aberrant ductules (C) are accessory ducts found outside the testis.

Reference Extracts:

Moore KL, Dalley AF, Agur AM. Clinically Oriented Anatomy. 7th ed. Lippincott Williams & Wilkins, 2013.

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

Hepatic adenomas are benign liver tumors strongly associated with long-term use of oral contraceptives and are most frequently found in women under 40. Hepatoblastoma is seen in children; hepatoma (HCC) is a malignant tumor typically found in cirrhotic livers. Cavernous hemangioma is unrelated to oral contraceptives.

According to Rumack’s Diagnostic Ultrasound:

“Hepatic adenomas occur predominantly in young women with a history of oral contraceptive use.”

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.).

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 demonstrates findings consistent with hypertrophic pyloric stenosis (HPS). This condition typically affects infants between 2 and 8 weeks of age and presents clinically with non-bilious projectile vomiting, weight loss, and dehydration.

In the ultrasound image, the classic “target” or “donut” sign can be seen in the transverse view of the hypertrophied pyloric muscle. Key sonographic criteria for HPS include:

Pyloric muscle thickness ≥3 mm

Pyloric channel length ≥15–18 mm

This imaging appearance strongly correlates with the clinical presentation of projectile vomiting (Choice D), which is the hallmark symptom of HPS.

Comparison of answer choices:

A. Abnormal prenatal ultrasound (Choice A) is not typically associated with HPS, which develops postnatally.

B. Neonatal hyperbilirubinemia (Choice B) is not an indication for a pyloric ultrasound and affects liver/biliary imaging.

C. Red currant jelly stools (Choice C) are indicative of intussusception, not HPS.

D. Projectile vomiting (Choice D) is the most common clinical indication leading to an ultrasound exam that reveals HPS.

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 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 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).

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 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.

Lateral decubitus positioning allows shifting of internal echoes within the bladder, helping differentiate mobile debris (such as blood clots or sediment) from adherent masses like tumors. This technique is helpful in evaluating questionable bladder filling defects.

According to Rumack’s Diagnostic Ultrasound:

“Changing the patient’s position, such as turning to the lateral decubitus, can help distinguish mobile debris from attached bladder wall lesions.”

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 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.

An ultrasound of a fetus AI-generated content may be incorrect.

The ultrasound image shows a transverse (axial) view of the fetal abdomen. Notably, there is abnormal continuity of renal parenchyma across the midline anterior to the aorta, forming a U- or horseshoe-shaped structure. This is characteristic of a congenital anomaly known as a horseshoe kidney.

Horseshoe kidney is the most common fusion anomaly of the kidneys, occurring in approximately 1 in 400–600 live births. It results from fusion of the lower poles of both kidneys during fetal development. On prenatal ultrasound, this anomaly can be suspected when the kidneys appear closer to the midline than usual and are connected by an isthmus of renal tissue or fibrous band that crosses anterior to the spine and great vessels.

Typical sonographic findings include:

Abnormally located kidneys, often lower than expected

Renal fusion across the midline (usually at the lower poles)

Possible associated hydronephrosis or malrotation

Comparison to other anomalies:

This is not consistent with polycystic kidney disease (which would show diffusely echogenic kidneys with poor corticomedullary differentiation).

Duplex kidney would show duplicated collecting systems but not fusion across the midline.

Renal agenesis would demonstrate absence of renal tissue.

Posterior urethral valves would show a distended bladder with bilateral hydronephrosis, not midline fusion.

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 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.