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2007 ACR Diagnostic Radiology In-Training Exam Rationales
Section X Chest Radiology
202. You are shown two axial images from a CT scan of the chest of a 48-year-
old woman with an abnormal chest radiograph (Figures 1A and 1B). Which one
of the following is the MOST LIKELY diagnosis?
A. Hamartoma
B. Carcinoid Tumor
C. Adenocarcinoma
D. Granuloma
Findings: Smooth bordered, round upper lobe mass with eccentric calcifications,
air-trapping and mucocoeles (best seen on lung windows).
RATIONALES:
A. Incorrect. Though the lesion is round, and well-circumscribed, this lesion does
not contain fat, which would be diagnostic for hamartoma. The calcifications are
chunkier than the classic popcorn calcifications of pulmonary hamartoma.
Usually, hamartomas have no effect on adjacent airways. The net result is that
hamartoma is possible but not the most likely.
B. Correct. The affiliation with the airway, round nature and chunky eccentric
calcifications are very typical for pulmonary carcinoid tumors. In fact, 40% of
carcinoids may be calcified on CT. Another feature of carcinoid tumors is their
effect on the airway (seen in up to 50% of cases). In this case, the effect is air-
trapping.
C. Incorrect. These lesions may be anywhere in the lung but tend to be
peripheral. They may present with areas of ground glass and somewhat
spiculated borders. Smaller lesions may be smooth bordered and round.
Calcifications may be eccentric in adenocarcinomas. Usually adenocarcinomas
do not result in air-trapping.
D. Incorrect. Granulomas tend to be smaller than 2 cm and are usually calcified.
When calcified, they are entirely calcified, centrally calcified or lamellated.
Airway effects from granulomas are rare. Though this lesion could be a
granuloma, its CT appearance is not suggestive of one.
References:
Chong S, Lee KS, Chung MJ, Han J, Kwon OJ, Kim TS. Neuroendocrine tumors
of the lung: clinical, pathologic, and imaging findings. Radiographics. 2006;26:41-
57
Jeung MY, Gasser B, Gangi A, Charneau D, Ducroq X, Kessler R, Quoix E, Roy
C. Bronchial carcinoid tumors of the thorax: spectrum of radiologic findings.
Radiographics. 2002;22:351-65.

203. You are shown two chest radiographs of a 49-year-old man with cough
(Figures 2A and 2B). Which one of the following is the MOST LIKELY
diagnosis?
A. Mucus plug
B. Central mass
C. Pneumonia
D. Loculated pleural effusion
Findings: Right upper lobe collapse from a central mass (Reverse S of Golden).
RATIONALES:
A. Incorrect.
B. Correct. This radiograph represents the classic findings of right upper lobe
collapse with increased opacity and volume loss. The central mass results in a
convex inferior border which simulates a backwards “S” when viewed adjacent to
the upper portion of collapse. This “Reverse S of Golden” should trigger the
reader to think of a mass when it is present, usually bronchogenic carcinoma.
C. Incorrect.
D. Incorrect.
References:
Woodring JH, Reed JC. Types and mechanisms of pulmonary atelectasis. J
Thorac Imag 1996;11:92-108.
Woodring JH, Reed JC. Radiographic manifestations of lobar atelectasis. J
Thorac Imag 1996;109-144.

204. You are shown three axial images from a CT scan of the chest of a 65 year
old woman (Figures 3 A-C). What is the MOST LIKELY diagnosis?
A. Relapsing polychondritis
B. Tracheomalacia
C. Post-intubation stricture
D. Saber-sheath trachea
RATIONALES:
A. Incorrect. Relapsing polychondritis is a rare autoimmune syndrome
characterized by recurrent episodes of cartilaginous inflammation. This leads to
destruction of the cartilaginous rings of the trachea resulting in thickening of the
trachea. The posterior membrane is spared as it doesn’t contain cartilage. This
helps distinguish from other causes, such as in this case of post-intubation
stricture.
B. Incorrect.
C. Correct. Post-intubation stricture results when the high pressure of an
endotracheal tube balloon results in tracheal mucosal necrosis. This eventually
leads to scarring and stenosis, which typically occurs just below the thoracic inlet
portion of the trachea.
D. Incorrect.
References:
Muller, N.L., Fraser, R.S., Colman, N.C., and Pare’, P.D. Radiologic Diagnosis
of Diseases of the Chest. W.B. Saunders, Co., Philadelphia, PA 2001

205. You are shown two axial images from a CT scan of the Chest of an 80-year
old-man (Figure 4A and 4B). Which of the following drugs is MOST LIKELY
responsible for the radiographic finding?
A. Bleomycin
B. Penicillamine
C. Amiodarone
D. Nitrofurantoin
Findings: CT scan of the Chest shows high attenuation reticular opacities in both lower
lobes of the lung and high attenuation of the liver.
RATIONALES:
A. Incorrect.
B. Incorrect.
C. Correct. Amiodarone is a triiodinated compound used in the treatment of
cardiac arrhythmias. Pulmonary toxicity occurs in 5-10 % of the patients. The
risk is increased if the daily maintenance dose is greater than 400 mg and if the
patient is elderly. Combination of high attenuation abnormalities in the lung and
liver on CT scan are characteristics radiographic features of amiodarone toxicity.
D. Incorrect.
References:
Webb, WR, Muller, NL, Naidich DP. High Resolution CT of the lung. Lippincott-
Raven Publishers, Philadelphia, PA 1996

206. You are shown two axial images from a CT scan of the Chest of an 80-year-
old woman (Figures 5A and 5B). What is the MOST LIKELY diagnosis?
A. Bronchogenic carcinoma
B. Lipoid pneumonia
C. Cryptogenic organizing pneumonia
D. Streptococcus pneumonia
RATIONALES:
A. Incorrect
B. Correct. Lipoid pneumonia is caused by aspiration of mineral oil. The disease
occurs in elderly individuals who frequently use oil for constipation. The
radiographic features include air space consolidation with spiculation or linear
opacities. These changes are the result of interlobular septal thickening caused
by infiltration of lipid laden macrophages and chronic inflammation. The
presence of fat in the consolidation strongly favors this diagnosis. These
features are present in the test case.
C. Incorrect
D. Incorrect
References:

207. You are shown a single axial image from a CT scan of the chest of a 30-
year-old woman (Figure 6). Which type of nodule is demonstrated?
A. Centrilobular
B. Tree-in-bud
C. Miliary
D. Perilymphatic
RATIONALES:
A. Correct. Centrilobular nodules or opacities occur in the center of the
secondary lobule. They reflect bronchiolar or peribronchiolar abnormalities in the
centrilobular distribution. They are typically seen 5 to 10 mm from the pleural
surface. Since the lobules are evenly spaced, the nodules tend to appear evenly
spaced. The differential diagnosis includes endobronchial spread of infection /
tumor, hypersensitivity pneumonitis, pulmonary histiocytosis and vasculitis.
B. Incorrect
C. Incorrect
D. Incorrect
References:

208. Regarding pulmonary mycetoma, which one of the following is TRUE?
A. Patients are usually immunocomprised.
B. Cavity results from severe central cystic bronchiectasis.
C. They are most often seen in the upper lobes.
D. Hemoptysis results from angioinvasion by the fungal elements.
RATIONALES:
A. Incorrect. Actually, patients with mycetomas are usually immunocompetent.
These fungal elements colonize a cavity from other diseases (emphysema,
sarcoid, tuberculosis, etc).
B. Incorrect. Central bronchiectasis is associated with aspergillus but with allergic
bronchopulmonary aspergillosis (ABPA) not with mycetomas. The cavities are
usually from an underlying chronic lung disease.
C. Corrrect. Aspergillomas are usually seen in the upper lobes probably related
to the common sites of the large cavities in the most commonly associated
conditions (sarcoid, tuberculosis, emphysema).
D. Incorrect. The hemoptysis results from the fragile bronchial circulation which
feeds the cavity wall. These bronchials may need to be embolized and in certain
situations, may precipitate lobectomy.
References:
Franquet T, Muller NL, Gimenez A, Guembe P, de La Torre J, Bague S.
Spectrum of pulmonary aspergillosis: histologic, clinical, and radiologic findings.
Radiographics. 2001;21:825-37.
Hennebicque AS, Nunes H, Brillet PY, Moulahi H, Valeyre D, Brauner MW. CT
findings in severe thoracic sarcoidosis. Eur Radiol. 2005;15:23-30. Epub 2004
Sep 24.

209. Which of the following structures is a core or centrilobular component of the
secondary pulmonary lobule?
A. Pulmonary vein
B. Septum
C. Bronchiole
D. Lymphatic
RATIONALES:
A. Incorrect. The pulmonary vein is located in the peripheral portion of the
secondary lobule within the interlobular septum.
B. Incorrect. The interlobular septum is a band of fibrous tissue, which
surrounds the periphery of the secondary lobule.
C. Correct. The bronchiole forms the center of the lobule with its accompanying
pulmonary artery.
D. Incorrect. The lymphatic vessel is also located with the vein in the interlobular
septum.
References:
Heitzman ER, Maharian B, Berger I, et al. The secondary pulmonary lobule: A
practical concept for interpretation of radiographs. Radiology 1969; 93:508-513
Webb WR, Stein MG, Finkbeiner WE, et al: Normal and diseased isolated
lungs: High resolution CT. Radiology 1988; 166:81-87
Bergin C, Roqgli V, Coblentz C, et al. The secondary pulmonary lobule: Normal
and abnormal CT appearances. AJR 1988; 151;21-25

210. Concerning the solitary pulmonary nodule, which CT appearance is MOST
predictive of a primary lung carcinoma?
A. Laminated calcification
B. Solid density
C. Pure ground glass attenuation
D. Mixed solid and ground glass opacity
RATIONALES:
A. Incorrect. Laminated calcification in a nodule less than or equal to 2 cm in
diameter is an indication of a healed granulomatous infection, i.e. histoplasmosis
or tuberculosis.
B. Incorrect.
C. Incorrect.
D. Correct. In a CT screening study for lung cancer, Henschke et al found among 233
nodules a malignancy rate of 7% for solid nodules, 18% for pure ground glass and 63%
for part solid, part ground glass.
References:
Sigelman SS, Khouri NF, Lee FP, et al. Solitary pulmonary nodules, CT
assessment. Radiology 1986; 160:307-312
Hensche CI, Yankelwitz DF, Mirtheva R, et al. CT screening for lung cancer:
Frequency and significance of part solid and nonsolid nodules. AJR 2002;
178:1053-1057.

211. Eggshell calcification in hilar or mediastinal nodes occurs in which of the
following diseases?
A. Tuberculosis
B. Metastatic mucinous adenocarcinoma
C. Histoplasmosis
D. Sarcoidosis
RATIONALES:
A. Incorrect. Calcification in lymph nodes in granulomatous infections tends to be
diffuse with complete calcification of the node.
B. Incorrect. Calcification in mucinous adenocarcinoma is usually
psammonatous, i.e. punctate or flake like and distributed throughout the node.
C. Incorrect. Calcification in lymph nodes in granulomatous infections tends to
be diffuse with complete calcification of the node.
D. Correct. Calcification in lymph nodes in sarcoidosis is a late manifestation and
occurs in less than 5% of patients. The pattern is frequently of the eggshell (peripheral)
type but this is less commonly seen than in patients with sarcoidosis.
References:
Gawne-Cain ML, Hansell DM. The pattern and distribution of calcified medistinal
lymph nodes in sarcoidosis and tuberculosis: A CT study. Clin Radiol 1996;
51:263-267
Meller BH, Rosado-de-Christensen ML, McAdams HP, et al. Thoracic
sarcoidosis: Radiologic pathologic correlation. Radiographics 1995; 15:421-437
Brown K, Mund DF, Aberle DR, et al. Intrathoracic calcification: Radiographic
features and differential diagnoses. Radiographics 1994; 14:1247-1261

212. Which one of the following is MOST LIKELY to cause obliteration of a
portion of the descending aortic interface?
A. Pericardial cyst
B. Bronchogenic cyst
C. Lymphoma
D. Neurogenic tumor
RATIONALES:
A. Incorrect.
B. Incorrect.
C. Incorrect.
D. Correct. The descending aortic interface is formed by the juxtaposition of the
aerated lung and the opacity of the left lateral margin of the descending thoracic aorta.
The interface is visible from the top of the aortic arch to the level of the diaphragm
inferiorly. Since the descending thoracic aorta is a posterior structure, abnormalities
that obliterate the descending aortic interface are within the posterior mediastinum. Of
the choices provided, only neurogenic tumors occur in the posterior mediastinum.
Thus, they are most likely to obliterate the descending aortic interface.
References:

213. Which of the following statements about localized fibrous tumors of the
pleura is TRUE?
A. They are associated with asbestos exposure.
B. They are associated with hypertrophic pulmonary osteoarthropathy.
C. They account for the majority of pleural tumors.
D. Most of these tumors arise from parietal pleura.
RATIONALES:
A. Incorrect.
B. Correct. Localized fibrous tumor of the pleura are relatively rare tumors of the
pleura. About 80% of them arise from the visceral pleura. They affect male and
female patients equally. They are not associated with smoking, asbestos
exposure or other environmental pollutants. About half of the patients are
asymptomatic when the tumor is discovered incidentally. They occasionally
reach very large size and produce symptoms of cough, dyspnea and chest pain.
Paraneoplastic syndromes such as hypoglycemia and hypertrophic
osteoarthropathy are present in 4-5 % of the cases.
C. Incorrect.
D. Incorect.
References:
Mcloud, TC. Thoracic Radiology: The Requisites. Mosby, Inc., St. Louis, MO
1998

214. Concerning radiation pneumonitis, which of the following is TRUE?
A. It usually occurs 6 months after completion of radiation therapy.
B. Chemotherapeutic agents potentiate the effects of radiation.
C. The acute phase of injury manifests as traction bronchiectasis.
D. Preexisting lung disease has no effect on the development of radiation
pneumonitis.
RATIONALES:
A. Incorrect
B. Correct. Radiation pneumonitis is a complication of radiation therapy.
Multiple factors determine the development and appearance of pneumonitis.
They include, the volume of lung involved, the type of radiation used, the time
period over which radiation therapy was given, whether chemotherapy was given
at the same time, and whether there was preexisting lung disease to name a few.
Radiation pneumonitis is divided into early and late manifestations. The early or
acute pneumonitis occurs within 1 to 3 months following treatment and
radiographically appears as homogeneous or patchy ground glass opacities.
The changes evolve over the next 6 to 12 months and usually become stable
within 2 years. They appear radiographically as dense consolidation, traction
bronchiectasis and volume loss.
C. Incorrect
D. Incorrect
References:

215. Which one of the following diseases is MOST LIKELY to be a cause of
pulmonary artery aneurysm or pseudoaneurysm?
A. Pulmonary infection
B. Mediastinal fibrosis
C. Metastasis
D. Goodpasture’s syndrome
RATIONALES:
A. Correct. Pulmonary artery aneurysms are rare. They may occur secondary
to infection (Septic emboli, Tuberculosis etc.), catheter-related complications,
pulmonary hypertension or vasculitidies. The most common cause is probably
catheter-related complications. Rasmussen aneurysm is a mycotic aneurysm
that occurs in relation to tuberculus infection.
B. Incorrect
C. Incorrect
D. Incorrect
References:

216. Concerning pulmonary mycobacterium avium-intracellulare complex
infection, which one of the following is TRUE?
A. Cavitary lesions occur in patients with chronic obstructive pulmonary disease.
B. Centrilobular nodules occur in immunocompromised patients.
C. Mediastinal adenopathy occurs in elderly woman without underlying lung
disease.
D. RML and lingular bronchiectasis occurs in patients with hypersensitivity
pneumonitis.
RATIONALES:
A. Correct. Mycobacterium avium-intracellulare complex infection have four distinct
manifestations which occur in different sets of population depending on their underlying
clinical status. The classic infection occurs in elderly men with underlying chronic
obstructive pulmonary disease or pulmonary fibrosis. Radiographically, nodules and or
cavitations are seen in the upper lobes.
B. Incorrect. Mycobacterium avium-intracellulare complex infection in
immunocompromised patients appear as mediastinal or hilar adenopathy.
C. Incorrect. Mycobacterium avium-intracellulare complex infection in elderly
patients appear as RML and Lingular bronchiectasis with scattered tree-in-bud
opacities
D. Incorrect. Hypersensitivity pneumonitis secondary to Mycobacterium avium-
intracellulare exposure manifests as centrilobular ground glass opacities.
References:

217. Concerning lung cancer staging, which one of the following is MOST
indicative of unresectability?
A. Size of the tumor
B. Pleural effusion
C. Scalene node
D. Ipsilateral hilar adenopathy
RATIONALES:
A. Incorrect.
B. Incorrect.
C. Correct. Lung cancer staging is based on the TNM classification. Based on
this classification, stage III B and above is considered unresectable disease.
Stage III B constitutes N3 and/or T4 disease. N3 disease involves contralateral
hilar or mediastinal nodes or scalene or supraclavicular nodes. While T4 disease
involves invasion of tumor into mediastinum, heart, great vessels, trachea,
esophagus or chest wall as well malignant pleural or pericardial effusion.
D. Incorrect.
References:

218. Concerning Morgagni hernia, which one of the following is the MOST
common location for its occurrence?
A. Left cardiophrenic
B. Right cardiophrenic
C. Left paraspinal
D. Right paraspinal
RATIONALES:
A. Incorrect.
B. Correct. Morgagni hernia represents a congenital diaphragmatic defect.
They occur in the right cardiophrenic angle. The hernia sac usually contains
intraabdominal fat and may contain air filled loops of bowel.
C. Incorrect.
D. Incorrect.
References:

219. Which one of the following radiographic signs represents chronic deep vein
thrombosis at CT venography?
A. Central low attenuation
B. Perivenous soft tissue edema
C. Venous dilitation
D. Central calcification
RATIONALES:
A. Incorrect.
B. Incorrect
C. Incorrect.
D. Correct. The findings of chronic deep vein thrombosis on CT venography include
calcification of thrombi within veins as well as that of venous walls, shrunken veins and
presence of collateral vessels. Central low attenuation within veins, perivenous soft
tissue edema and venous dilatation are signs of acute deep vein thrombosis.
References:
Katz DS, Loud PA, Bruce D, Gittleman AM, Mueller R, Klippenstein DL,
Grossman ZD. Combined CT venography and pulmonary angiography: A
comprehensive review. Radiographics 2002; 22:S3-S24

220. Which one of the following is true regarding the ACR recommendation for
chest radiographs in patients requiring mechanical ventilation?
A. Daily
B. Twice a day
C. Every other day
D. Once a week
RATIONALES:
A. Correct. The ACR recommends daily portable chest radiographs in patients who are
on mechanical ventilation and in those who have acute cardiac or pulmonary disease.
Radiographs are also recommended following placement of support and monitoring
devices.
B. Incorrect.
C. Incorrect.
D. Incorrect
References:
American College of Radiology Standards for bedside radiographs.
(www.acr.org).

221. A computed radiography image with a 10-bit pixel depth will have how many
possible shades of gray?
A. 256
B. 1024
C. 4094
D. 8192
RATIONALES:
A. Incorrect.
B. Correct. Pixel depth is computed as 210
= 1024
C. Incorrect
D. Incorrect
222. A patient undergoes a chest CT in a trauma center and later found to be
pregnant. The radiation exposure to fetus is mainly from:
A. primary x-ray radiation.
B. internal scatter radiation.
C. external scatter radiation.
D. leakage radiation.
RATIONALES:
A. Incorrect
B. Correct.
C. Incorrect. External scatter radiation drops drastically from the edge of scan
field, i.e., chest. The exposure is minimal from external scatter.
D. Incorrect.

223. Concerning idiopathic pulmonary fibrosis, which of the following is TRUE
regarding the distribution of disease?
A. Upper and central
B. Upper and peripheral
C. Lower and central
D. Lower and peripheral
RATIONALES:
A. Incorrect
B. Incorrect
C. Incorrect
D. Correct. Idiopathic pulmonary fibrosis affects patients between 50 and 70 years old.
It is characterized by the development of relentlessly progressive fibrosis and is
associated with 2-3 year median length of survival from the time of diagnosis.
Radiographic findings include reticular opacities at the lung bases in peripheral
distribution.
References:

224. Concerning cysts noted in the lung on High Resolution CT scan of the
chest, which one of the following is TRUE?
A. They are spherical and uniform in Langerhans cell histiocytosis.
B. They lack a well defined wall in early centrilobular emphysema.
C. They are spherical and in the upper lobes in panlobular emphysema.
D. They are irregular and in the upper lobes in lymphangioleiomyomatosis.
RATIONALES:
A. Incorrect. In Langerhans cell histiocytosis. The cysts are often irregular and
seen in the upper lobes.
B. Correct. In early centrilobular emphysema the cystic areas within the lung
have an imperceptible wall. In later stages, the entire secondary lobule, except
the lobular wall is destroyed and can appear as multiple adjacent polygonal
cysts.
C. Incorrect. The disease is in the lower lobes.
D. Incorrect. The cysts are smooth and round and they are evenly distributed
throughout the lungs.
References:

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