- Which of the following infections can cause multifocal lung opacities?
- A) Tuberculosis
- B) Bacterial pneumonia
- C) Fungal infection
- D) Viral pneumonia
Answer: A) Tuberculosis, B) Bacterial pneumonia, C) Fungal infection, and D) Viral pneumonia
Comment (Correct Answer): All of these infections can cause multifocal lung opacities, though their presentations may vary. Bacterial pneumonia frequently shows multifocal consolidations, tuberculosis can present as focal or miliary patterns, fungal infections may produce nodules, and viral pneumonias often lead to ground-glass opacities.
“Multifocal lung opacities may be caused by bacterial infections presenting with consolidation, tuberculosis in focal or miliary patterns, fungal infections producing nodules, and viral pneumonias causing ground-glass opacities.” (Radiopaedia)
- Which imaging finding is most characteristic of multifocal lung metastases?
- A) Ground-glass opacities
- B) Cavitating nodules
- C) Smooth, well-circumscribed nodules
- D) Air bronchograms
Answer: B) Cavitating nodules and C) Smooth, well-circumscribed nodules
Comment (Correct Answer): Multifocal lung metastases often appear as smooth, well-circumscribed nodules. Metastatic squamous cell carcinoma can also present as cavitating nodules due to central necrosis. Additionally, adenocarcinoma with lepidic growth can present with multifocal findings and air bronchograms.
“Metastatic disease typically presents as multiple well-circumscribed nodules, often distributed randomly. Cavitating nodules can occur with squamous cell carcinoma metastases. Adenocarcinoma with lepidic growth often presents with air bronchograms in multifocal patterns.” (Radiology Key)
- Which of the following conditions can present as multifocal cavitating lung nodules?
- A) Pulmonary embolism (septic)
- B) Metastatic squamous cell carcinoma
- C) Tuberculosis
- D) All of the above
Answer: D) All of the above
Comment (Correct Answer): Septic pulmonary embolism, metastatic squamous cell carcinoma, and tuberculosis can all cause multifocal cavitating nodules, although the underlying mechanisms differ.
“Septic emboli, squamous cell carcinoma metastases, and tuberculosis are all potential causes of cavitating nodules in the lung.” (Radiopaedia)
- True or False: Pulmonary infarcts caused by embolism can appear as multifocal opacities.
- A) True
- B) False
Answer: A) True
Comment (Correct Answer): Pulmonary embolism can result in infarcts that appear as multifocal wedge-shaped opacities, typically in a subpleural distribution.
“Pulmonary infarcts secondary to embolism commonly present as subpleural, wedge-shaped opacities on imaging.” (Radiopaedia)
- Which of the following findings helps differentiate multifocal lung opacities caused by CHF from those caused by infection?
- A) Perihilar and dependent distribution
- B) Cavitation within nodules
- C) Ground-glass opacities
Answer: A) Perihilar and dependent distribution
Comment (Correct Answer): Multifocal opacities in CHF typically follow a perihilar and dependent distribution due to pulmonary venous congestion, unlike infectious opacities which are more random.
“Pulmonary edema in CHF presents with a characteristic perihilar and dependent distribution, helping differentiate it from infectious etiologies.” (Radiopaedia)Incorrect Answers:
- B) Cavitation within nodules
“Cavitation is not a feature of CHF but may occur in infectious or neoplastic processes.” (AJR) - C) Ground-glass opacities
“Ground-glass opacities can occur in CHF but are less specific for distinguishing it from infection.” (Radiopaedia)