Page 154 - Feline diagnostic imaging

9.4 Mediastinum 155

(a) (b)

Figure 9.3 Lateral (a) and ventrodorsal (b) thoracic radiographs of a normal obese cat. On the lateral view, a large amount of
mediastinal fat is noted in the ventral aspect of the mediastinum, ventral to the heart. The lungs are moderately increased in opacity
due to poor inspiratory effort. The costal portion of the caudal ribs appears fragmented, a normal variation in some older cats (arrow).
On the VD view (b), the cranial mediastinum is widened secondary to fat accumulation. Fat also surrounds the heart, blurring the
margins. The extracostal musculature is increased in prominence due to interposed and contrasting body wall fat (arrows).

(a)

(b)

Figure 9.4 Right lateral (a) and left lateral (b) thoracic radiographs of a normal adult cat. Note that there is minimal difference
in the appearance of the heart and diaphragm between the lateral views. Differences are much more obvious in medium to large
dogs. The pulmonary parenchyma is within normal limits. Most of the normal background opacity is secondary to peripheral
pulmonary arteries and veins.