Note pleural based density in film's lateral
Beam divergence concept is helpful in
lesion localization .
Note the inner and outer rib cage. In lateral
view, the left
side is close to the cassette. The beam divergence makes the right hemithorax wider.
The right diaphragm projects beyond along with the right ribs.
The arrow points to the pleural based lesion. From the
lateral view, using the beam divergence concept, you can say the lesion is
located on the left side.