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AOBR Radiology study materials
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AOBR Radiology practice questions

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Question 1Diagnostic Radiology

Which imaging modality uses ionizing radiation to produce cross-sectional images by measuring the attenuation of X-rays through tissue?

  1. Computed tomography Correct answer.
  2. Magnetic resonance imaging
  3. Ultrasound
  4. Nuclear medicine scintigraphy

Explanation

CT reconstructs cross-sectional images from the differential attenuation of an X-ray beam rotated around the patient. MRI uses magnetic fields and radiofrequency pulses, ultrasound uses sound waves, and scintigraphy detects injected radiopharmaceuticals.

Question 2Diagnostic Radiology

On a standard chest radiograph, which structure normally forms the right border of the mediastinum?

  1. Aortic arch
  2. Pulmonary trunk
  3. Right atrium Correct answer.
  4. Left ventricle

Explanation

The right heart border on a frontal chest radiograph is formed by the right atrium, sitting above the diaphragm. The left border is formed sequentially by the aortic knob, pulmonary artery, left atrial appendage, and left ventricle.

Question 3Diagnostic Radiology

Which radiographic finding is most characteristic of a simple pneumothorax on an upright chest radiograph?

  1. Visible visceral pleural line with no lung markings beyond it Correct answer.
  2. Air bronchograms within the consolidated lung
  3. Kerley B lines at the lung bases
  4. Bilateral hilar enlargement

Explanation

A pneumothorax produces a thin visceral pleural edge separated from the chest wall by a radiolucent space devoid of bronchovascular markings. Air bronchograms suggest airspace consolidation, hilar enlargement suggests adenopathy or vascular congestion, and Kerley lines indicate interstitial edema.

Question 4Diagnostic Radiology

Which ultrasound appearance is typical of a simple hepatic cyst?

  1. Hypoechoic mass with a thick irregular wall
  2. Hyperechoic lesion with posterior acoustic shadowing
  3. Mixed echogenicity with internal vascular flow
  4. Anechoic lesion with posterior acoustic enhancement Correct answer.

Explanation

A simple cyst contains fluid that does not reflect sound, so it appears anechoic with enhanced through-transmission behind it. Shadowing suggests calcification or gas, and internal flow or thick walls suggest a solid or complex lesion.

Question 5Diagnostic Radiology

What is the principal advantage of using intravenous iodinated contrast in abdominal CT?

  1. It increases attenuation differences between vascular and avascular tissues Correct answer.
  2. It shortens the acquisition time of the scan
  3. It reduces the radiation dose delivered to the patient
  4. It eliminates beam-hardening artifacts

Explanation

Iodine is highly attenuating, so contrast enhancement increases the density difference between perfused and non-perfused structures, improving lesion detection. Contrast does not lower radiation dose, does not meaningfully shorten scan time, and can itself create artifacts.

Question 6Diagnostic Radiology

Which finding on a plain abdominal radiograph most suggests a mechanical small bowel obstruction?

  1. Multiple dilated small bowel loops with air-fluid levels Correct answer.
  2. A single dilated loop of large bowel
  3. Diffuse gaseous distension of the stomach only
  4. Calcific densities over the right upper quadrant

Explanation

Mechanical small bowel obstruction classically shows centrally located dilated loops with valvulae and air-fluid levels on upright or decubitus views. A single large bowel loop suggests colonic dilatation, and upper quadrant calcifications suggest gallstones.

Question 7Diagnostic Radiology

Which MRI sequence produces bright signal from fluid such as cerebrospinal fluid?

  1. Diffusion-weighted
  2. Gradient echo
  3. T2-weighted Correct answer.
  4. T1-weighted

Explanation

On T2-weighted images, tissues with long T2 relaxation times such as CSF and edema appear hyperintense. T1-weighted images show fluid as dark, and diffusion and gradient-echo sequences are not primarily designed to display fluid as bright.

Question 8Diagnostic Radiology

The ALARA principle in radiology refers to which practice?

  1. Keeping radiation dose as low as reasonably achievable Correct answer.
  2. Scheduling examinations at the earliest available time
  3. Limiting contrast volume to the smallest effective dose
  4. Restricting imaging to adult patients only

Explanation

ALARA is the radiation-protection principle that exposures should be kept as low as reasonably achievable while obtaining the necessary diagnostic information. It concerns optimization of radiation dose, not contrast dosing, scheduling, or age restriction.

Question 9Diagnostic Radiology

A 62-year-old presents with sudden onset of severe abdominal pain and a pulsatile epigastric mass. Which imaging study is most appropriate for initial evaluation of a suspected abdominal aortic aneurysm?

  1. CT angiography of the abdomen Correct answer.
  2. Barium enema
  3. Upper gastrointestinal endoscopy
  4. Plain abdominal radiograph

Explanation

CT angiography delineates aneurysm size, extent, and complications such as rupture or leak with high sensitivity. A barium enema and endoscopy evaluate the bowel lumen, and a plain radiograph is insensitive for aneurysm assessment.

Question 10Diagnostic Radiology

A patient with acute right lower quadrant pain undergoes CT. Which finding most supports acute appendicitis?

  1. Mild diffuse colonic gas
  2. A simple hepatic cyst
  3. A dilated appendix with periappendiceal fat stranding Correct answer.
  4. A collapsed appendix measuring 4 mm

Explanation

Acute appendicitis typically shows an enlarged appendix greater than 6 mm with wall thickening and surrounding inflammatory fat stranding. A normal-caliber collapsed appendix argues against appendicitis, and the other findings are incidental.

Question 11Diagnostic Radiology

Which chest radiograph finding is most consistent with a large left-sided pleural effusion?

  1. Blunting of the left costophrenic angle with a meniscus Correct answer.
  2. Shift of the trachea toward the left with volume loss
  3. Air bronchograms in the left lower lobe
  4. Hyperlucency of the left hemithorax

Explanation

Pleural fluid collects dependently, obliterating the costophrenic angle and forming a meniscus that rises laterally. Hyperlucency suggests pneumothorax, and air bronchograms indicate parenchymal consolidation.

Question 12Diagnostic Radiology

On MRI of the brain, which lesion appearance most suggests an acute infarct on diffusion-weighted imaging?

  1. Restricted diffusion with bright signal on DWI and low ADC Correct answer.
  2. Hyperintensity on T1-weighted images only
  3. Bright signal on DWI with high ADC
  4. Uniform low signal on both DWI and ADC

Explanation

Acute infarction causes cytotoxic edema with restricted water diffusion, producing hyperintensity on DWI and corresponding hypointensity on the ADC map. High ADC indicates facilitated diffusion such as vasogenic edema or chronic change.

Question 13Diagnostic Radiology

A 45-year-old woman has recurrent right upper quadrant pain after fatty meals; ultrasound shows mobile echogenic foci with acoustic shadowing in the gallbladder. What is the most likely diagnosis?

  1. Renal cell carcinoma
  2. Cholelithiasis Correct answer.
  3. Hepatic hemangioma
  4. Acute pancreatitis

Explanation

Mobile echogenic foci within the gallbladder that cast acoustic shadows are gallstones, and postprandial right upper quadrant pain is typical biliary colic. Pancreatitis, hemangioma, and renal tumor do not produce this sonographic pattern.

Question 14Diagnostic Radiology

Which feature most reliably distinguishes a benign from a malignant pulmonary nodule on CT?

  1. Smooth margins
  2. Diameter of 5 mm
  3. Location in the upper lobe
  4. Stability in size over two years Correct answer.

Explanation

Lack of growth over a two-year period strongly favors a benign etiology for a solid nodule. Small size and smooth margins are reassuring but less definitive, and lobar location does not determine benignity.

Question 15Diagnostic Radiology

Which imaging modality is preferred for first-line evaluation of suspected acute cholecystitis when ultrasound is nondiagnostic?

  1. Barium swallow
  2. Upper gastrointestinal series
  3. Plain abdominal radiograph
  4. Cholescintigraphy (HIDA scan) Correct answer.

Explanation

Cholescintigraphy assesses cystic duct patency and is highly sensitive for acute cholecystitis when ultrasound is equivocal. Barium studies and plain films do not evaluate the biliary tree functionally.

Question 16Diagnostic Radiology

What is the Hounsfield unit range typically used to identify simple fluid on CT?

  1. 60 to 100 HU
  2. 0 to 20 HU Correct answer.
  3. -100 to -50 HU
  4. 150 to 300 HU

Explanation

Simple fluid such as a cyst or ascites typically measures near water density, approximately 0 to 20 HU. Fat is negative, acute hemorrhage is higher, and bone or calcification is far higher.

Question 17Diagnostic Radiology

A chest radiograph shows a widened mediastinum after blunt trauma. Which next step is most appropriate?

  1. Upper endoscopy
  2. Transthoracic echocardiography
  3. Repeat chest radiograph in 24 hours
  4. CT angiography of the chest Correct answer.

Explanation

A widened mediastinum after trauma raises concern for aortic injury, and CT angiography is the definitive noninvasive test. Delay, echocardiography, and endoscopy do not adequately evaluate the thoracic aorta in this setting.

Question 18Diagnostic Radiology

Which sonographic sign is most specific for acute cholecystitis rather than simple gallstones?

  1. A sonographic Murphy sign with gallbladder wall thickening Correct answer.
  2. Echogenic bile
  3. A single mobile gallstone
  4. Posterior acoustic shadowing

Explanation

Focal tenderness over the gallbladder combined with wall thickening and pericholecystic fluid indicates inflammation, distinguishing cholecystitis from uncomplicated stones. Stones and shadowing occur in asymptomatic cholelithiasis.

Question 19Diagnostic Radiology

Which MRI finding is characteristic of a simple bone cyst in a child?

  1. Sclerotic lesion with sunburst periosteal reaction
  2. Permeative destruction with cortical breakthrough
  3. Well-defined lytic lesion with fluid signal and no aggressive features Correct answer.
  4. Soft tissue mass with surrounding edema

Explanation

A simple bone cyst appears as a well-marginated lucent lesion with fluid signal and no cortical destruction or soft tissue component. Permeative destruction, soft tissue mass, and sunburst periosteal reaction suggest aggressive lesions.

Question 20Diagnostic Radiology

Which principle explains why MRI is generally preferred over CT for evaluating the spinal cord?

  1. Lower cost per examination
  2. Superior soft tissue contrast without ionizing radiation Correct answer.
  3. Better visualization of cortical bone detail
  4. Faster acquisition times

Explanation

MRI provides excellent contrast between cord, CSF, and surrounding soft tissues and avoids ionizing radiation. CT is faster and better for bone detail, and MRI is generally more expensive.

Question 21Diagnostic Radiology

Which imaging finding is most suggestive of a bowel obstruction complicated by ischemia?

  1. Dilated loops with air-fluid levels alone
  2. Pneumatosis intestinalis and reduced bowel wall enhancement Correct answer.
  3. Mild mesenteric fat stranding only
  4. Increased bowel wall enhancement

Explanation

Pneumatosis and absent or reduced mural enhancement indicate compromised perfusion and impending infarction. Simple dilatation with air-fluid levels and mild stranding reflect obstruction without necessarily ischemia, and increased enhancement is not the ischemic pattern.

Question 22Diagnostic Radiology

A patient with a known primary malignancy has multiple small pulmonary nodules with a random distribution on high-resolution CT. What is the most likely explanation?

  1. Idiopathic pulmonary fibrosis
  2. Centrilobular emphysema
  3. Sarcoidosis
  4. Hematogenous metastases Correct answer.

Explanation

Randomly distributed nodules reflect hematogenous spread and are typical of metastatic disease. Sarcoidosis usually produces perilymphatic nodules, centrilobular emphysema causes lucent areas without nodules, and fibrosis produces reticulation and honeycombing.

Question 23Diagnostic Radiology

Which imaging feature best distinguishes a liver hemangioma from hepatocellular carcinoma on multiphase CT?

  1. Portal vein thrombosis
  2. Capsule enhancement in the portal venous phase
  3. Arterial hyperenhancement with washout
  4. Peripheral nodular enhancement with centripetal fill-in Correct answer.

Explanation

Hemangiomas show discontinuous peripheral nodular enhancement with progressive centripetal fill-in on delayed phases. Arterial enhancement with washout, capsule enhancement, and portal vein thrombosis favor hepatocellular carcinoma.

Question 24Diagnostic Radiology

A young adult presents with sudden severe headache; noncontrast head CT shows subarachnoid hemorrhage. Which vascular imaging study is most appropriate to identify the source?

  1. CT angiography of the head Correct answer.
  2. Magnetic resonance venography
  3. Carotid duplex ultrasound
  4. Digital subtraction angiography of the lower extremities

Explanation

CT angiography rapidly identifies an intracranial aneurysm or vascular malformation as the cause of subarachnoid hemorrhage. Carotid duplex and lower extremity angiography assess extracranial vessels, and MR venography evaluates venous sinuses.

Question 25Diagnostic Radiology

Which finding on high-resolution CT most supports usual interstitial pneumonia?

  1. Subpleural basal honeycombing with traction bronchiectasis Correct answer.
  2. Ground-glass opacity with consolidation
  3. Upper lobe centrilobular nodules
  4. Mediastinal lymphadenopathy alone

Explanation

The pattern of usual interstitial pneumonia is characterized by subpleural, basal-predominant reticulation, honeycombing, and traction bronchiectasis. Centrilobular nodules and consolidation suggest other processes such as infection or organizing pneumonia.

Question 26Diagnostic Radiology

Which radiographic density appears most radiolucent on a plain radiograph?

  1. Bone
  2. Fat
  3. Air Correct answer.
  4. Soft tissue

Explanation

Radiolucency reflects how little a material attenuates the X-ray beam, and air attenuates least of the listed tissues, so it appears darkest. Attenuation increases through fat, soft tissue, and bone in ascending order, making bone the most radiopaque.

Question 27Diagnostic Radiology

Which contrast agent property makes gadolinium-based agents suitable for MRI?

  1. Reflection of ultrasound waves at interfaces
  2. Emission of positrons detectable by a scanner
  3. Paramagnetic shortening of T1 relaxation time Correct answer.
  4. High atomic number producing X-ray attenuation

Explanation

Gadolinium is paramagnetic and shortens T1 relaxation, which increases signal on T1-weighted images in tissues where it accumulates. It does not attenuate X-rays, emit positrons, or generate ultrasound reflectivity.

Question 28Diagnostic Radiology

Which structure is best evaluated with a high-frequency linear ultrasound transducer rather than a low-frequency curvilinear probe?

  1. Superficial thyroid gland Correct answer.
  2. Full-term gravid uterus
  3. Deep pelvic organs
  4. Adult liver

Explanation

High-frequency transducers provide better spatial resolution but poorer penetration, making them suited to superficial structures such as the thyroid. Deep abdominal and pelvic organs require lower frequencies to achieve adequate penetration.

Question 29Diagnostic Radiology

A 70-year-old smoker has a solitary 2.5 cm lung nodule with smooth margins and a popcorn-like pattern of calcification on CT. Which diagnosis is most likely?

  1. Lung abscess
  2. Solitary metastasis
  3. Hamartoma Correct answer.
  4. Bronchogenic carcinoma

Explanation

Popcorn-like calcification within a well-circumscribed pulmonary nodule is characteristic of a hamartoma, which is benign. Malignancy and metastases rarely show this pattern, and an abscess would appear cavitary with an air-fluid level rather than densely calcified.

Question 30Diagnostic Radiology

Which CT finding is the most reliable sign of a completed, nonviable bowel infarction?

  1. Pneumatosis intestinalis with portomesenteric gas Correct answer.
  2. Engorgement of mesenteric vessels
  3. Mural thickening of the affected loop
  4. Fat stranding around the bowel

Explanation

Gas within the bowel wall and portal venous system indicates transmural necrosis with gas-forming organisms and is a late, highly specific sign of infarction. Mural thickening, vessel engorgement, and stranding are nonspecific and may occur with reversible ischemia or inflammation.

Question 31Diagnostic Radiology

A 30-year-old sustains knee trauma; radiographs are normal but MRI shows a linear band of low signal on all sequences crossing the distal femur, with surrounding marrow edema. Which diagnosis is most consistent?

  1. Bone infarct
  2. Osteosarcoma
  3. Occult trabecular fracture Correct answer.
  4. Chondromyxoid fibroma

Explanation

A linear low-signal band spanning the bone with adjacent marrow edema after trauma represents an occult trabecular fracture not visible on radiographs. Osteosarcoma shows an aggressive mass with cortical destruction, and bone infarcts have serpiginous sclerotic margins without a traumatic linear band.

Question 32Diagnostic Radiology

A 25-year-old woman has a well-defined solid renal mass that is hyperdense on unenhanced CT and shows homogeneous enhancement after contrast. Which feature most favors oncocytoma over renal cell carcinoma?

  1. Central stellate scar on multiphase imaging Correct answer.
  2. Heterogeneous necrosis
  3. Invasion of the renal vein
  4. Peripheral nodular enhancement

Explanation

A central stellate scar with homogeneous enhancement is classically described in oncocytoma, although imaging overlap with chromophobe renal cell carcinoma exists and biopsy may be required. Venous invasion and heterogeneous necrosis favor malignancy.

Question 33Diagnostic Radiology

Which pattern of enhancement on multiphase CT most suggests focal nodular hyperplasia rather than hepatic adenoma?

  1. Arterial hyperenhancement with a central scar and isointensity on portal venous phase Correct answer.
  2. Arterial hyperenhancement that becomes hypointense on portal venous phase
  3. Peripheral discontinuous enhancement with progressive centripetal filling
  4. No enhancement on any phase

Explanation

Focal nodular hyperplasia typically enhances avidly in the arterial phase, contains a central scar, and becomes nearly isointense to liver on portal venous and delayed phases. Washout to hypointensity favors adenoma or hepatocellular carcinoma, while centripetal filling indicates hemangioma.

Question 34Diagnostic Radiology

Which imaging feature most reliably distinguishes a benign thyroid nodule from a suspicious one on ultrasound?

  1. Microcalcifications within a solid hypoechoic nodule Correct answer.
  2. Spongiform appearance
  3. Anechoic simple cystic appearance
  4. Comet-tail artifact from colloid

Explanation

Microcalcifications, especially within a solid hypoechoic nodule, are a highly specific suspicious feature associated with papillary thyroid carcinoma. Simple cysts, colloid with comet-tail artifact, and spongiform nodules are benign patterns.

Question 35Diagnostic Radiology

A patient with suspected pulmonary embolism has a normal chest radiograph and normal renal function. Which test is the most appropriate next step for diagnosis?

  1. Ventilation-perfusion scintigraphy
  2. D-dimer without further imaging
  3. Lower extremity ultrasound
  4. CT pulmonary angiography Correct answer.

Explanation

CT pulmonary angiography is the first-line study for suspected pulmonary embolism when the patient is hemodynamically stable and renal function permits iodinated contrast. V/Q scanning is reserved for contrast contraindications, and D-dimer alone cannot establish the diagnosis when clinical probability is high.

Question 36Diagnostic Radiology

A 55-year-old with chronic headache has an MRI showing a well-defined extra-axial mass that is isointense to gray matter, broad-based on the dura, and enhances homogeneously with a dural tail. Which diagnosis is most likely?

  1. Glioblastoma
  2. Meningioma Correct answer.
  3. Epidermoid cyst
  4. Metastasis to the brain

Explanation

An extra-axial dural-based mass that is isointense to cortex and enhances homogeneously with a dural tail is characteristic of a meningioma. Glioblastoma is intra-axial and ring-enhancing, while an epidermoid cyst restricts diffusion and does not enhance.

Question 37Diagnostic Radiology

A 60-year-old with progressive dyspnea has HRCT showing bilateral lower-lobe honeycombing, traction bronchiectasis, and a basal-to-apical gradient. Which diagnosis is most consistent?

  1. Hypersensitivity pneumonitis pattern
  2. Organizing pneumonia pattern
  3. Usual interstitial pneumonia pattern Correct answer.
  4. Langerhans cell histiocytosis pattern

Explanation

Honeycombing with traction bronchiectasis in a subpleural, basal-predominant distribution defines the usual interstitial pneumonia pattern. Hypersensitivity pneumonitis typically shows centrilobular nodules and air trapping, while organizing pneumonia shows patchy consolidation.

Question 38Diagnostic Radiology

A trauma patient has a pelvic radiograph showing a widened symphysis pubis and vertical shear displacement. Which additional finding is most strongly associated with this injury pattern?

  1. Disruption of the posterior sacroiliac ligament complex Correct answer.
  2. Avulsion of the lesser trochanter
  3. Isolated pubic ramus fracture without ring disruption
  4. Isolated fracture of the femoral neck

Explanation

A vertically unstable pelvic ring injury with symphysis widening implies disruption of the posterior ligamentous complex, which is critical for stability and risk of hemorrhage. Isolated ramus fractures and proximal femoral fractures do not produce this ring instability pattern.

Question 39Diagnostic Radiology

A 3-day-old neonate has bilious vomiting; abdominal radiograph shows a normal gas pattern proximally with a paucity of distal gas. Which diagnosis must be excluded urgently?

  1. Necrotizing enterocolitis
  2. Meconium plug syndrome
  3. Malrotation with midgut volvulus Correct answer.
  4. Hypertrophic pyloric stenosis

Explanation

Bilious vomiting in a neonate is a surgical emergency until malrotation with midgut volvulus is excluded, and an upper gastrointestinal series is the definitive study. Pyloric stenosis presents with nonbilious vomiting, and meconium plug syndrome typically shows distal bowel distension.

Question 40Diagnostic Radiology

A patient with a known skull base tumor has an MRI in which the lesion is hyperintense on T1-weighted images before contrast. Which characteristic best explains this finding?

  1. Restriction of water diffusion within the lesion
  2. Presence of calcification within the lesion
  3. High cellularity with enlarged nuclei
  4. Presence of fat, proteinaceous fluid, or melanin within the lesion Correct answer.

Explanation

Intrinsic T1 hyperintensity before contrast reflects short T1 relaxation caused by substances such as fat, proteinaceous fluid, subacute hemorrhage, or melanin. Restricted diffusion and high cellularity affect diffusion-weighted imaging and do not by themselves produce precontrast T1 hyperintensity.

Question 41Vascular & Interventional Radiology

Which vessel is the preferred access site for most diagnostic angiographic procedures because of its large caliber and ease of compression?

  1. Brachial artery
  2. Common femoral artery Correct answer.
  3. Radial artery
  4. Axillary artery

Explanation

The common femoral artery is large, superficial, and overlies the femoral head, allowing effective manual compression after sheath removal. Radial access is increasingly used but is chosen for other reasons such as lower bleeding risk and patient mobility. Brachial and axillary approaches are reserved for specific indications because of higher complication rates.

Question 42Vascular & Interventional Radiology

During angiography, which catheter shape is designed with a preformed curve to selectively engage the renal arteries from a femoral approach?

  1. Balloon occlusion catheter
  2. Pigtail catheter
  3. Cobra or Simmons catheter Correct answer.
  4. Straight flush catheter

Explanation

Selective visceral and renal engagement typically requires a preformed curved catheter such as a Cobra or Simmons configuration. Pigtail and straight catheters are used for nonselective injection and flushing. Balloon catheters are used for occlusion or angioplasty rather than selective engagement.

Question 43Vascular & Interventional Radiology

What is the primary mechanism by which iodinated contrast media can cause acute kidney injury after angiography?

  1. Direct tubular cytotoxicity and medullary hypoxia Correct answer.
  2. Renal artery vasodilation
  3. Immune complex glomerulonephritis
  4. Obstruction of collecting tubules by crystals

Explanation

Contrast-induced acute kidney injury is believed to result from a combination of direct tubular epithelial toxicity and medullary ischemia from altered renal hemodynamics. It is not an immune-complex or crystal-obstruction process. Vasoconstriction, rather than vasodilation, contributes to medullary hypoxia.

Question 44Vascular & Interventional Radiology

Which finding on a diagnostic angiogram most directly indicates a hemodynamically significant stenosis?

  1. Vessel tortuosity proximal to the lesion
  2. Calcification along the vessel wall
  3. Atheroma in the contralateral limb
  4. A pressure gradient across the lesion Correct answer.

Explanation

A translesional pressure gradient provides functional evidence that a stenosis limits flow. Tortuosity, calcification, and contralateral disease are anatomic observations that do not by themselves prove hemodynamic significance. Measuring the gradient helps decide whether intervention is warranted.

Question 45Vascular & Interventional Radiology

Which complication is most specifically associated with a high radial artery puncture and is avoided by puncturing distal to the radial artery bifurcation?

  1. Compartment syndrome of the forearm Correct answer.
  2. Median nerve injury
  3. Retrograde passage into the vertebral artery
  4. Radial artery pseudoaneurysm

Explanation

Puncture near the radial artery bifurcation risks entering a small-caliber vessel that can bleed into the forearm compartments. Distal puncture in the true radial artery over the radius reduces this risk. Nerve injury, vertebral entry, and pseudoaneurysm are separate concerns.

Question 46Vascular & Interventional Radiology

A patient with a known heparin-induced thrombocytopenia history requires an arteriogram. Which anticoagulant strategy is most appropriate for the procedure?

  1. Low-molecular-weight heparin
  2. Warfarin loading
  3. Argatroban Correct answer.
  4. Unfractionated heparin bolus

Explanation

In heparin-induced thrombocytopenia, all heparin products are contraindicated, and a direct thrombin inhibitor such as argatroban is used for procedural anticoagulation. Low-molecular-weight heparin cross-reacts and is also avoided. Warfarin is not used for acute procedural anticoagulation.

Question 47Vascular & Interventional Radiology

What is the most common cause of a pseudoaneurysm at the femoral access site?

  1. Puncture of the superficial femoral artery
  2. Excessive anticoagulation reversal
  3. Inadequate hemostasis after sheath removal Correct answer.
  4. Use of a closure device

Explanation

Femoral pseudoaneurysms most often result from incomplete hemostasis, allowing blood to track into surrounding tissue while the arterial wall defect persists. Puncture of the superficial femoral artery is a risk factor for bleeding complications but not the direct mechanism of pseudoaneurysm formation. Closure device use and anticoagulation reversal are not the primary causes.

Question 48Vascular & Interventional Radiology

Which imaging modality is the reference standard for confirming a clinically suspected deep vein thrombosis when duplex ultrasound is equivocal?

  1. Computed tomography venography
  2. Radionuclide venography
  3. Catheter-directed venography Correct answer.
  4. Magnetic resonance venography

Explanation

Catheter-directed contrast venography directly visualizes the venous lumen and remains the reference standard for equivocal cases. CT and MR venography are alternatives but are less commonly used as the confirmatory standard. Radionuclide venography has largely been replaced.

Question 49Vascular & Interventional Radiology

A patient presents with a pulsatile groin mass and a bruit one week after cardiac catheterization. Which finding on duplex ultrasound would confirm a pseudoaneurysm?

  1. A high-resistance arterial waveform in the sac
  2. Absent flow within the sac
  3. A to-and-fro flow pattern in the neck of the sac Correct answer.
  4. Monophasic flow in the common femoral vein

Explanation

A pseudoaneurysm shows a characteristic to-and-fro flow pattern in the communicating neck during systole and diastole. Monophasic venous flow is a normal finding, and absent sac flow would not support the diagnosis. High-resistance arterial waveforms are nonspecific.

Question 50Vascular & Interventional Radiology

Which condition is an absolute contraindication to percutaneous transluminal angioplasty of an iliac artery stenosis?

  1. Active infection at the puncture site Correct answer.
  2. Severe claudication despite medical therapy
  3. Atherosclerotic calcification
  4. Rest pain with a short-segment stenosis

Explanation

Active infection at the planned access site is an absolute contraindication because of the risk of introducing infection into the bloodstream or the treated vessel. Claudication and rest pain with suitable anatomy are indications, and calcification is a technical challenge rather than an absolute contraindication.