Chest x-ray abnormalities
Lobes, fissures and contours
Zones or lobes?
Although it is generally best to refer to the location of lung abnormalities in terms of zones, occasionally you will see signs, that will tell you which specific lobe is involved.
Right middle lobe disease
The right middle lobe is bordered superiorly by the horizontal fissure, and medially by the right heart border. Any abnormality, which increases density of this lobe, may therefore obscure the right heart border, or be limited superiorly by the horizontal fissure.
Key points
- Two views are usually needed to determine the lobe involved
- Knowledge of the fissures and the diaphragm and heart contours can help determine where disease is located without the need for a lateral view
- Involvement of the right middle lobe may obscure the right heart border, and/or be limited by the horizontal fissure
Hover over image to show findings
Right middle lobe consolidation
- The right heart border (right atrial edge) is obscured
- Consolidation (*) is limited above by a crisp line, formed by the horizontal fissure
- The pathology must therefore involve the right middle lobe
- More extensive shadowing also involves the right and left peri-hilar regions
Clinical information
- Child with a cough and fever
Diagnosis
- Pneumonia involving the right middle lobe
Click image to align with the top of the page
Horizontal fissure displacement
Displacement of the horizontal fissure may be another indicator of the location of pathology. If the fissure is displaced upwards, this may be because of volume loss of the right upper lobe, for example due to collapse, or fibrosis. If the horizontal fissure is displaced downwards, there may be a process which has caused volume loss of the right lower lobe.
Hover over image to show findings
Right upper lobe collapse
- The horizontal fissure (white line) has been displaced upwards from its original position (red line)
- Dense opacification (*) of the medial part of the right upper zone
- Enlarged right hilum
Clinical information
- Smoker
- Progressive shortness of breath and cough
Diagnosis
- Right upper lobe collapse
Other investigations
- Bronchoscopy revealed a lung cancer causing obstruction to the right upper lobe bronchus
Major fissures
The major (oblique) fissures cannot be identified on a frontal chest x-ray. This is because they are oriented obliquely en-face.
Hover over image to show findings
Left lower lobe cavity - frontal view
- Large, round, thick-walled lung cavity
- The cavity is in the left middle zone, close to the hilum
- Which lobe do you think it is in? See the lateral view below
Hover over image to show findings
Left lower lobe cavity - lateral view
- The cavity is behind the oblique fissure (blue line) and so must be in the lower lobe
Clinical information
- Long term smoker with a cough
Diagnosis
- Left lower lobe lung cavity - in this case due to a squamous cell lung carcinoma