What is the likely general pathological condition present in this patient?
Emphysema is characterised by alveolar destruction and hyperexpansion. Name two signs of hyperexpansion demonstrated on this radiograph.
Flattening of the hemidiaphragms and widening of the retrosternal space. Both are best appreciated on the lateral projection.
As well as hyperexpansion, there are focal areas of reduced lung markings, e.g. right midzone. What is the cause?
Focal hyperlucencies are due to underlying destruction of lung architecture, there is bullous formation. When bullae are apical or peripheral, there is a risk that they can be misinterpreted as pneumothoraces resulting in needle aspiration or drain insertion (neither of which should be performed).
Marked hyperinflation of the lungs (note over 11 posterior ribs visible on PA projection, flattened hemidiaphragms, increased retrosternal air space) and hyperlucency of the lungs with distorted parenchymal architecture.