Good body condition. Inspiratory radiograph.

Mild new bone formation visible ventral to T4/5 and T12/13 (spondylosis). Small osteophyte visible at the infraglenoid tubercles of one scapula. Abdominal detail within normal limits.

There is mild convex bulging of the ventral border of the cranial mediastinum. Overall the opacity at the level of the cranial mediastinum appears increased. The trachea runs almost parallel to the thoracic spine with a mild dorsal buldging at the level of the 3rd to 4th intercostal space. Dorsal to the 2nd sternebra a poorly delineated soft tissue opaque structure is visible.

The lung shows an overall, severely increased opacity. Between the cardiac silhouette and the diaphragm it is of almost soft tissue opacity, however the diaphragmatic outline can still be identified. On close inspection also fine white lines can also be seen in the affected areas; they represent vessels. The remaining lung shows more reticular changes. Throughout the entire lung field multiple, soft tissue nodules are visible.

• Severe interstitial pattern with multiple small soft tissue nodules (reticulonodular)
• Convexity of the cranial mediastinum
• Soft tissue dens structure dorsal to the 2nd sternebra
• Spondylosis
• Mild osteoarthrosis shoulder

The lung changes are highly suspicious for a neoplasia (primary versus secondary).

The changes of the cranial mediastinum are suspicious for a cranial mediastinal mass. Differential diagnoses include enlarged cranial mediastinal lymphnodes, mass arising from the oesophagus (neoplasia, granuloma) as well as mediastinal haemorrhage, abcesses, granuloma or inflammation (for example due to perforation of the oesophagus, nocardiosis).

The soft tissue structure dorsal to the 2nd sternebra is most likely an enlarged sternal lymphnode.

The severe opacification caudodorsal to the cardiac silhouette can be due to superimposition of severely altered lung parenchyma. As only a single lateral radiograph is available a caudal mediastinal mass, for example arising from the oesophagus, a hematoma, an abcess or a granuloma cannot be excluded. A second radiograph would be required to assess this change further.

In combination with the lung changes a neoplasia with metastasis to the sternal and mediastinal lymphnodes appears the most likely differential diagnosis.

• Left lateral and ventrodorsal radiograph
• And/or Computed tomography of the lung

Computed tomography of the thorax confirmed the severe interstitial lung pattern with multiple soft tissue nodules. The sternal as well as the cranial mediastinal lymphnodes were severely enlarged.

Caudal to the heart no other mass lesions were visible, therefore the radiographic changes are most likely due to superimposition of the lung changes.

Lucky had a carcinoma of the larynx with metastasis to the lung and lymphnodes.

A heavy interstitial lung pattern can mimic an alveolar lung pattern. Don’t get fooled by the first impression. On close inspection there are usually still some vessels visible.