"Hidden" lung mass, dog

Large, right-middle lung lobe mass: The ventrodorsal view (middle image) indicates the presence of an alveolar opacity/soft tissue mass in the right middle lung lobe, which is not visible at all on the right lateral projection (right image). However, the mass is clearly observed on the left lateral view (left image). This lesion could have been completely missed on a radiographic examination consisting of a single right lateral view.