10 year old Golden Retriever

Findings

There is a large mass effect in the cranial thorax, with elevation of the trachea. The cranial mediastinum is widened on the dorsoventral projection. The lung lobes are retracted and there are visible fissure lines. There is alveolar pattern visible in the ventral aspect of the right cranial lung lobe on the left lateral projection which has rounded margins. The cardiac silhouette is difficult to evaluate but appears normal in size on the dorsoventral projection. There is mild widening of the mainstem bronchi. On a lateral radiograph of the neck, there is mild soft tissue swelling ventral to the larynx. The right 5th rib has an old fracture and callus formation.