The thoracic esophagus is dilated and gas filled. It is visible on both lateral projections and superimposed on the heart and spine on the d/v projection.
There is alveolar pulmonary pattern in the left and right cranial lung lobes and the right middle lung lobe. These are seen best on the lateral projections.
Aspiration pneumonia is a common complication of megaesophagus. Because the distribution of aspiration pneumonia is ventral, it is often not visible on a v/d or d/v projection as it is superimposed on the heart and mediastinum. Two lateral projections are needed to evaluate the lungs.