L1 Question 1: Which of the following best describes a fissural nodule on chest CT?
a) A nodule located within the lung parenchyma with no relation to the pleura
b) A nodule along or adjacent to the pulmonary fissures
c) A subsolid nodule with central cavitation
d) A cystic lesion with thin walls
e) None of the above
Answer: b) A nodule along or adjacent to the pulmonary fissures
Comment: Fissural nodules are defined as small opacities occurring along or adjacent to the pleural fissures, often related to lymphatic spread or pleural processes.
“Fissural nodules are small opacities occurring along or adjacent to the pleural fissures of the lungs, often due to lymphatic spread or pleural-based processes.” Radiopaedia
Incorrect Answers:
a) “A nodule located within the lung parenchyma without pleural involvement does not fit the definition of a fissural nodule.” Radiopaedia
c) “Subsolid nodules with central cavitation are often seen in necrotic or infectious conditions rather than fissural nodules.” Radiology Key
d) “Cystic lesions with thin walls are not characteristic of fissural nodules but may represent benign cystic lung disease.” Radiology Key
e) “None of the above is incorrect, as option b best describes a fissural nodule.” Radiopaedia
L1 Question 2: Which condition is most commonly associated with perilymphatic fissural nodules?
a) Sarcoidosis
b) Pneumocystis jiroveci pneumonia
c) Centrilobular emphysema
d) Cryptogenic organizing pneumonia (COP)
e) Asbestosis
Answer: a) Sarcoidosis
Comment: Sarcoidosis frequently involves the perilymphatic regions, including the fissures, due to its predilection for lymphatic involvement.
“Sarcoidosis frequently involves perilymphatic regions, including the fissures, due to its predilection for lymphatic involvement.” Radiopaedia
Incorrect Answers:
b) “Pneumocystis pneumonia often presents with diffuse ground-glass opacities rather than perilymphatic nodules.” Radiopaedia
c) “Centrilobular emphysema is characterized by areas of low attenuation rather than nodular opacities.” Radiopaedia
d) “COP often presents with subpleural consolidation rather than perilymphatic nodules.” Radiology Key
e) “Asbestosis commonly presents with pleural plaques rather than perilymphatic nodules.” Radiographics
L2 Question 3: Which of the following patterns of nodular distribution is least likely to be associated with a malignant fissural nodule?
a) Thick-walled nodule with irregular margins
b) Multiple small nodules clustered along the fissure
c) Small, round, stable nodule without metabolic activity
d) Confluent nodules with pleural effusion
e) Nodules with central cavitation
Answer: c) Small, round, stable nodule without metabolic activity
Comment: Benign nodules tend to remain stable over time and lack metabolic activity on PET-CT imaging, unlike malignant nodules, which often show progression and metabolic activity.
“Benign nodules tend to remain stable over time and lack metabolic activity on PET-CT imaging, unlike malignant nodules which often show progression and metabolic activity.” Radiopaedia
Incorrect Answers:
a) “Thick-walled nodules with irregular margins are often associated with malignancy.” Radiopaedia
b) “Multiple clustered nodules can suggest metastatic disease.” Radiology Key
d) “Confluent nodules with pleural effusion can indicate aggressive malignancy.” Radiopaedia
e) “Cavitating nodules often suggest necrotic malignancy or infection.” Radiology Key
L2 Question 4: A 45-year-old patient with suspected sarcoidosis presents with scattered pulmonary nodules and multiple nodules along the pleural fissures on chest CT. Which feature most strongly suggests sarcoidosis in this case?
a) Scattered small nodules in both lung bases
b) Nodules located predominantly along the pleural fissures
c) Ground-glass opacities with centrilobular distribution
d) Confluent opacities with air bronchograms
e) Unilateral large nodule with calcification
Answer: b) Nodules located predominantly along the pleural fissures
Comment: Nodules located along the pleural fissures are a hallmark of perilymphatic involvement, which is a classic feature in sarcoidosis.
“Sarcoidosis frequently involves perilymphatic regions, including the pleural fissures, due to its predilection for lymphatic spread.” Radiopaedia
Incorrect Answers:
a) “Scattered nodules without fissural involvement are more consistent with conditions like hypersensitivity pneumonitis.” Radiopaedia
c) “Ground-glass opacities with centrilobular distribution are more typical of infections like Pneumocystis jiroveci pneumonia or hypersensitivity pneumonitis.” Radiopaedia
d) “Confluent opacities with air bronchograms are more typical of pneumonia rather than sarcoidosis.” Radiology Key
e) “A unilateral large nodule with calcification is less typical for sarcoidosis and more characteristic of granulomatous infection or neoplasm.” Radiographics
L2 Question 6: A 60-year-old asymptomatic patient undergoing routine screening is found to have an isolated oval nodule along the major fissure. What is the next best step according to Fleischner Society Guidelines?
a) No follow-up required
b) Follow-up CT in 6-12 months
c) PET-CT for metabolic assessment
d) Immediate biopsy
e) Annual CT surveillance for 5 years
Answer: b) Follow-up CT in 6-12 months
Comment: An isolated oval nodule along the fissure, especially in an asymptomatic patient, often requires short-term follow-up rather than immediate biopsy due to its low likelihood of malignancy.
*”The Fleischner Society recommends follow-up CT in 6-12 months for small isolated pulmonary nodules in low-risk patients, as the likelihood of malignancy is low for nodules of this size and characteristics. Management decisions should be based on nodule size, morphology, and patient risk factors.” Fleischner Society Guidelines PMC