Chest radiology - masterclass Flashcards
How to tell if a CXR is adequately inspired?
If a CXR is adequately inspired, the anterior ends of at least 6 ribs should be visible
What are the pulmonary hila?
The hila are the junctions between the heart and lungs, where the pulmonary arteries and bronchi enter and the pulmonary veins exit the lungs
•The left hilum normally lies higher than the right
On a normal CXR, the right diaphragm lies about 1.5cm above the left diaphragm. True/false?
True
Major deviations from this usually indicate disease
When looking at the lungs, divide into upper mid and lower zones. Should be roughly same size and density. True/false?
True
Major deviations from this usually indicate disease
What to look for in CXR of lung apices?
lung apices: masses (e.g. Pancoast tumour), pneumothorax
What to look for in CXR behind the heart?
behind the heart: consolidation, masses, hiatus hernia
What to look for in CXR below diaphragm?
below the diaphragm: free gas, lines and tubes (e.g. nasogastric tube), gastric distension, bowel obstruction
What to look for in CXR of bones and soft tissues?
bones and soft tissues: fractures, masses, mastectomy, subcutaneous emphysema, evidence of previous surgery (e.g. axillary clips)
What is the lingula?
the tip or tongue-like projection of the upper lobe of the left lung
Causes of bronchial obstruction?
tumours, aspirated foodstuffs, mucus impaction etc.
Appearance of left lower lobe collapse on CXR?
Volume loss on the left with elevation of the hemidiaphragm, left hemithorax looks small
Increased density in left retrocardiac region (region on left side behind heart).
Loss of clarity medial aspect left hemidiaphragm
•Left hilum displaced downwards
Appearance of left upper lobe collapse on CXR?
Volume loss on the left, elevation of the left hemidiaphragm
•Loss of clarity of the heart shadow
•‘veil like opacity’ diffuse opacification of the left hemithorax
Consolidation follows the same patterns in terms of position/obscuring borders, but without the volume loss. True/false?
True
Infection of the lingula causes the right heart border to become obscured. True/false?
False
Obscuring left heart border.since lingula on left lung
What is the pleural cavity?
The pleural cavity is a potential space visible on chest radiographs when it is filled by fluid (pleural effusion) or air (pneumothorax).
What are the costophrenic angles?
formed by the points at which the chest wall and diaphragm meet.
Bottom edges where lungs meet sides of chest wall.
How does pleural effusion affect costophrenic angles?
On an erect CXR dense pleural fluid is seen to collect at the lung bases and often forms the curved appearance of a ‘meniscus’ at the lung edges, blunting the costophrenic angles
How to spot a small pneumothorax on CXR?
A small pneumothorax is subtle – look for a dark crescent without lung markings bounded medially by the lung edge. It is often at the lung apex.
How to spot a large pneumothorax on CXR?
A larger right pneumothorax, note the lung edge and the black air filled pleural space with no lung markings
Appearance of heart failure on CXR?
A good mnemonic to remember these principles is ABCDE:
•A - alveolar oedema (bat wing opacities)
•B - Kerley B lines
•C - cardiomegaly
•D - dilated upper lobe vessels
•E - pleural effusion
Doctors often have to insert lines and tubes into patients in order to monitor treatment, provide nutrition. What are some examples?
Endotracheal (ET) tubes
Nasogastric tubes
Central venous lines
Normal position of ET tubes?
tip 5 cm above carina
width 2/3 tracheal diameter
cuff should not expand the trachea
Malposition of ET tubes?
tip may extend past the carina
malposition most commonly seen is the tip in the right main bronchus
May have entered the oesophagus
