Diagnostic Radiology: Respiratory System

Question 1

Case 1: Pneumothorax

• Sudden pleuritic chest pain
• Dyspnea

Answer 1

1. ***Hyperlucent hemithorax —> No vascular lung markings
2. ***Absence of lung outlines
3. Larger intercostal space
4. ***Mediastinal + Tracheal shift
5. ***Flattening of Hemidiaphragm
6. Slight depression of left heart border (if left pneumothorax)

Question 2

Case 2: Pneumonia

- Productive cough + Fever

Answer 2

1. ***Increased density
2. Hazy + Indistinct border
3. ***Air bronchogram
4. Segmental / Lobar distribution

Question 3

Case 3: Left lower lobe collapse

• Chronic smoker
• Cough + Blood stained sputum

Answer 3

1. Dense triangular shadow behind the heart (Sail sign)
2. ***Loss of clarity of L hemidiaphragm
3. ***Displacement of left hilum downwards (pulled downwards) (usually left mid-hilar point higher than right)
4. ***Increased lucency in rest of ipsilateral lung (compensate for collapse of 1 lobe)

Question 4

Case 4: Heart failure

Answer 4

1. ***Cardiomegaly
2. ***Bilateral perihilar haze
3. ***Upper lobe venous diversion
4. ***Pleural effusion

Question 5

Case 5: Bronchogenic carcinoma

Answer 5

1. ***Thick-walled lung mass
2. ***Central cavitation
3. ***Air-fluid level within cavitation
4. ***Volume loss with tethering of hemidiaphragm

Question 6

Case 6: Pulmonary secondaries to Osteogenic sarcoma

Answer 6

Multiple dense nodules of variable size (***Cannon ball lesions)

Question 7

Case 8: Usual interstitial pneumonitis from Rheumatoid arthritis

Answer 7

1. Bilateral ***reticulonodular shadowing
2. ***Loss of lower lung volumes
3. Shaggy heart borders + diaphragms

CT:

• ***Ground glass opacity (reversible)
• ***Honey-combing (irreversible)

Question 8

Case 9: Pulmonary embolism

Answer 8

1. ***Wedge-shaped peripheral consolidation
2. ***Blunting of left CP angle

CT pulmonary angiogram:
- multiple emboli in pulmonary arteries with peripheral wedge shaped infarct

Question 9

Case 10: Neurofibroma

Answer 9

1. Extrapulmonary mass (no cervicothoracic sign: posterior to trachea)
2. Pleural based
3. Paraspinal
4. Vertebral / disc disease
5. Neurogenic lesions