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

The ultrasound image demonstrates an irregular, complex fluid collection in the subareolar region of the breast with internal echoes, septations, and poorly defined margins. These sonographic findings are classic for a breast abscess, particularly in a patient presenting with clinical signs of infection—fever, redness, and localized tenderness.

A breast abscess is typically seen as:

A hypoechoic or anechoic area with thick walls

Presence of internal debris, septations, or floating echoes

Posterior acoustic enhancement

Increased peripheral vascularity on Doppler (surrounding inflammation)

Surrounding hyperechoic fat due to cellulitis

This clinical and imaging profile strongly supports the diagnosis of a breast abscess, most commonly seen in lactating women (puerperal mastitis) or in non-lactating women with chronic infection.

Comparison of answer choices:

A. Ductal ectasia usually presents with dilated ducts and minimal inflammatory changes, often asymptomatic or causing nipple discharge.

B. Abscess — Correct. The irregular fluid collection with complex echoes and clinical signs of infection supports this.

C. Sebaceous cysts are typically superficial, round, and well-defined with a punctum.

D. Galactocele appears as a well-circumscribed, fat-fluid level–containing lesion in lactating women but lacks surrounding inflammation.

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.”

Before performing a paracentesis, assessment of the patient's coagulation status is crucial to minimize bleeding risk. The International Normalized Ratio (INR) is the standard lab value used to assess coagulation. Elevated INR may increase the risk of bleeding complications during the procedure. ALT, AFP, and bilirubin levels evaluate liver function or cancer progression but are not directly relevant to bleeding risk for this procedure.

As per AASLD and SIR guidelines:

“An INR and platelet count should be evaluated before paracentesis to assess bleeding risk. Minor elevations in INR (<1.5) may not contraindicate the procedure.” (AASLD Practice Guidance, 2021; SIR Consensus Guidelines, 2019).

Direct inguinal hernias protrude through Hesselbach's triangle, which lies medial to the inferior epigastric artery. In contrast, indirect inguinal hernias pass lateral to the inferior epigastric artery via the deep inguinal ring.

According to Moore’s Clinically Oriented Anatomy:

“Direct inguinal hernias occur medial to the inferior epigastric vessels, within Hesselbach's triangle.”

An intimal flap in the aorta is a hallmark ultrasound finding of aortic dissection, which can present with tearing chest/abdominal pain and differential blood pressures between arms. The flap represents separation of the intimal and medial layers of the aortic wall.

According to Rumack’s Diagnostic Ultrasound:

“An intimal flap visualized within the aorta is diagnostic of an aortic dissection.”

Histoplasmosis is a fungal infection that can lead to granulomatous disease. Chronic granulomatous infections may result in multiple splenic calcifications that appear as small echogenic foci with shadowing on ultrasound. Other infectious granulomas (e.g., tuberculosis) may present similarly.

According to Rumack's Diagnostic Ultrasound:

“Granulomatous infections such as histoplasmosis and tuberculosis may produce multiple splenic calcifications, often with shadowing.”

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.”

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 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.

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.).