NBME Radiology Form 139 Exam With
Actual 120 Questions & Verified
Answers,Plus Rationales/Expert
Verified For Guaranteed Pass Graded
A+/ 2025/2026 /Latest Update/Instant
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1. A 65-year-old smoker with chronic cough has a solitary 2.5 cm pulmonary nodule on
chest radiograph. Which feature on CT is most suggestive of malignancy?
A. Popcorn calcification
B. Homogeneous fat attenuation
C. Spiculated margins
D. Central punctate calcification
Answer: C. Spiculated margins
Rationale: Spiculated margins reflect irregular tumor growth and desmoplastic
reaction, which are highly suspicious for malignancy; benign nodules more often
show fat or characteristic calcification patterns.
2. Which imaging modality is most sensitive for detecting acute ischemic stroke within
the first 6 hours?
A. Noncontrast CT head
B. Diffusion-weighted MRI (DWI)
C. CT angiography
D. MR angiography
Answer: B. Diffusion-weighted MRI (DWI)
Rationale: DWI detects cytotoxic edema within minutes to hours and is the most
sensitive for early ischemia; noncontrast CT may be normal early on.
3. On abdominal radiograph, which radiographic sign suggests small bowel obstruction?
A. Free subdiaphragmatic air
B. Right upper quadrant air-fluid levels only
C. Multiple dilated small-bowel loops with air-fluid levels and paucity of colonic gas
D. Diffuse ground-glass bowel haziness
, Answer: C. Multiple dilated small-bowel loops with air-fluid levels and paucity of
colonic gas
Rationale: These are classic features of small-bowel obstruction; transition point
and collapsed colon support SBO diagnosis.
4. A patient with metallic foreign body in the orbit should avoid which imaging
modality?
A. Noncontrast CT
B. MRI
C. Plain radiograph
D. Ultrasound (if external)
Answer: B. MRI
Rationale: MRI can move ferromagnetic metallic foreign bodies, risking tissue
injury; CT or plain films are preferred to localize metallic intraorbital objects.
5. In mammography, what appearance is most suspicious for invasive ductal carcinoma?
A. Large coarse calcifications
B. Round, well-circumscribed mass
C. Irregular spiculated mass
D. Oil cysts with fat-fluid level
Answer: C. Irregular spiculated mass
Rationale: Spiculated, irregular masses on mammography are highly suspicious for
invasive carcinoma; benign entities are usually well-circumscribed or have
characteristic calcifications.
6. Which imaging finding on CT is most suggestive of hepatic hemangioma?
A. Uniform delayed washout
B. Peripheral nodular discontinuous enhancement with centripetal fill-in
C. Early arterial hyperenhancement with rapid washout in portal phase
D. Fatty attenuation throughout lesion
Answer: B. Peripheral nodular discontinuous enhancement with centripetal fill-in
Rationale: Hemangiomas classically show peripheral nodular enhancement in
arterial phase with progressive centripetal fill-in on delayed phases.
7. What is the best initial imaging test for suspected pulmonary embolism in a
hemodynamically stable patient?
A. Ventilation-perfusion (V/Q) scan
B. CT pulmonary angiography (CTPA)
C. Pulmonary angiography
D. Chest radiograph alone
Answer: B. CT pulmonary angiography (CTPA)
Rationale: CTPA is the first-line test in stable patients due to high sensitivity and
specificity and its ability to evaluate alternative diagnoses.
, 8. A “double duct sign” on imaging (dilated common bile duct and pancreatic duct)
suggests which diagnosis?
A. Acute appendicitis
B. Hepatic adenoma
C. Pancreatic head mass (e.g., adenocarcinoma)
D. Choledocholithiasis alone
Answer: C. Pancreatic head mass (e.g., adenocarcinoma)
Rationale: A mass in the pancreatic head can obstruct both ducts causing the
double-duct sign; stones typically affect the biliary tree only.
9. Which ultrasound finding is most consistent with acute appendicitis in a child?
A. Noncompressible tubular structure >6 mm in diameter in the right lower quadrant
B. Presence of hypermobile bowel loops
C. Noncompressible blind-ending tubular structure >6 mm with increased color
Doppler flow
D. Peristaltic compressible loop with air artifact
Answer: C. Noncompressible blind-ending tubular structure >6 mm with increased
color Doppler flow
Rationale: Noncompressible appendix >6 mm diameter with periappendiceal
hyperemia supports acute appendicitis; increased Doppler flow indicates
inflammation.
10. On chest radiograph, Kerley B lines indicate which pathology?
A. Pneumothorax
B. Pleural effusion only
C. Interstitial pulmonary edema
D. Lobar consolidation
Answer: C. Interstitial pulmonary edema
Rationale: Kerley B lines are short horizontal lines at lung peripheries due to
interlobular septal thickening from interstitial edema, commonly from congestive
heart failure.
11. Which MRI sequence is most sensitive for detecting fat within a lesion?
A. T1 with gadolinium
B. T2 FLAIR
C. Chemical shift (in- and out-of-phase) imaging
D. Diffusion-weighted imaging
Answer: C. Chemical shift (in- and out-of-phase) imaging
Rationale: In-/out-of-phase imaging exploits differences in resonance between fat
and water, detecting microscopic fat by signal drop on out-of-phase images.
12. A 45-year-old woman has focal asymmetric breast density on mammogram but
normal ultrasound. Next best step?
Actual 120 Questions & Verified
Answers,Plus Rationales/Expert
Verified For Guaranteed Pass Graded
A+/ 2025/2026 /Latest Update/Instant
Download Pdf
1. A 65-year-old smoker with chronic cough has a solitary 2.5 cm pulmonary nodule on
chest radiograph. Which feature on CT is most suggestive of malignancy?
A. Popcorn calcification
B. Homogeneous fat attenuation
C. Spiculated margins
D. Central punctate calcification
Answer: C. Spiculated margins
Rationale: Spiculated margins reflect irregular tumor growth and desmoplastic
reaction, which are highly suspicious for malignancy; benign nodules more often
show fat or characteristic calcification patterns.
2. Which imaging modality is most sensitive for detecting acute ischemic stroke within
the first 6 hours?
A. Noncontrast CT head
B. Diffusion-weighted MRI (DWI)
C. CT angiography
D. MR angiography
Answer: B. Diffusion-weighted MRI (DWI)
Rationale: DWI detects cytotoxic edema within minutes to hours and is the most
sensitive for early ischemia; noncontrast CT may be normal early on.
3. On abdominal radiograph, which radiographic sign suggests small bowel obstruction?
A. Free subdiaphragmatic air
B. Right upper quadrant air-fluid levels only
C. Multiple dilated small-bowel loops with air-fluid levels and paucity of colonic gas
D. Diffuse ground-glass bowel haziness
, Answer: C. Multiple dilated small-bowel loops with air-fluid levels and paucity of
colonic gas
Rationale: These are classic features of small-bowel obstruction; transition point
and collapsed colon support SBO diagnosis.
4. A patient with metallic foreign body in the orbit should avoid which imaging
modality?
A. Noncontrast CT
B. MRI
C. Plain radiograph
D. Ultrasound (if external)
Answer: B. MRI
Rationale: MRI can move ferromagnetic metallic foreign bodies, risking tissue
injury; CT or plain films are preferred to localize metallic intraorbital objects.
5. In mammography, what appearance is most suspicious for invasive ductal carcinoma?
A. Large coarse calcifications
B. Round, well-circumscribed mass
C. Irregular spiculated mass
D. Oil cysts with fat-fluid level
Answer: C. Irregular spiculated mass
Rationale: Spiculated, irregular masses on mammography are highly suspicious for
invasive carcinoma; benign entities are usually well-circumscribed or have
characteristic calcifications.
6. Which imaging finding on CT is most suggestive of hepatic hemangioma?
A. Uniform delayed washout
B. Peripheral nodular discontinuous enhancement with centripetal fill-in
C. Early arterial hyperenhancement with rapid washout in portal phase
D. Fatty attenuation throughout lesion
Answer: B. Peripheral nodular discontinuous enhancement with centripetal fill-in
Rationale: Hemangiomas classically show peripheral nodular enhancement in
arterial phase with progressive centripetal fill-in on delayed phases.
7. What is the best initial imaging test for suspected pulmonary embolism in a
hemodynamically stable patient?
A. Ventilation-perfusion (V/Q) scan
B. CT pulmonary angiography (CTPA)
C. Pulmonary angiography
D. Chest radiograph alone
Answer: B. CT pulmonary angiography (CTPA)
Rationale: CTPA is the first-line test in stable patients due to high sensitivity and
specificity and its ability to evaluate alternative diagnoses.
, 8. A “double duct sign” on imaging (dilated common bile duct and pancreatic duct)
suggests which diagnosis?
A. Acute appendicitis
B. Hepatic adenoma
C. Pancreatic head mass (e.g., adenocarcinoma)
D. Choledocholithiasis alone
Answer: C. Pancreatic head mass (e.g., adenocarcinoma)
Rationale: A mass in the pancreatic head can obstruct both ducts causing the
double-duct sign; stones typically affect the biliary tree only.
9. Which ultrasound finding is most consistent with acute appendicitis in a child?
A. Noncompressible tubular structure >6 mm in diameter in the right lower quadrant
B. Presence of hypermobile bowel loops
C. Noncompressible blind-ending tubular structure >6 mm with increased color
Doppler flow
D. Peristaltic compressible loop with air artifact
Answer: C. Noncompressible blind-ending tubular structure >6 mm with increased
color Doppler flow
Rationale: Noncompressible appendix >6 mm diameter with periappendiceal
hyperemia supports acute appendicitis; increased Doppler flow indicates
inflammation.
10. On chest radiograph, Kerley B lines indicate which pathology?
A. Pneumothorax
B. Pleural effusion only
C. Interstitial pulmonary edema
D. Lobar consolidation
Answer: C. Interstitial pulmonary edema
Rationale: Kerley B lines are short horizontal lines at lung peripheries due to
interlobular septal thickening from interstitial edema, commonly from congestive
heart failure.
11. Which MRI sequence is most sensitive for detecting fat within a lesion?
A. T1 with gadolinium
B. T2 FLAIR
C. Chemical shift (in- and out-of-phase) imaging
D. Diffusion-weighted imaging
Answer: C. Chemical shift (in- and out-of-phase) imaging
Rationale: In-/out-of-phase imaging exploits differences in resonance between fat
and water, detecting microscopic fat by signal drop on out-of-phase images.
12. A 45-year-old woman has focal asymmetric breast density on mammogram but
normal ultrasound. Next best step?
