Small Animal Radiology and Ultrasound: A Diagnostic Atlas and Text

228 Small Animal Radiolo g y and Ultrasono graphy
Fig. 2-213 A 13-year-old female
mixed breed dog with multiple
mammary tumors. A close-up view
of the lateral thoracic radiograph
reveals multiple small mineralized
densities superimposed over the cardiac
silhouette (arrows). The small
uniform size and calcified density of
these nodules indicate that they are
pulmonary or pleural osteomas.
There is no evidence of pulmonary
metastasis. Diagnosis: Pulmonary or
pleural osteomas.
node calcification has been observed also (see Fig. 2-190). 584 Another source of densely
mineralized nodular densities and tracheobronchial lymph nodes is aspiration of barium
from an earlier diagnostic procedure. 584,645
Systemic diseases, such as Cushing’s disease, primary and secondary hyperparathyroidism,
and hypervitaminosis D, can produce varying degrees of intrapulmonary calcification.
646 These changes usually are distributed evenly throughout the lung and involve the
bronchial walls and pulmonary interstitial tissue. Small nodular calcifications may be present.
647 Many of these animals have other soft-tissue calcifications (e.g., vascular or subcutaneous).
Some instances of rapidly progressive pulmonary calcification have been
described in which the etiology was not established.
CERVICAL SOFT-TISSUE ABNORMALITIES
PHARYNGEAL ABNORMALITIES
Abnormalities of the oral or nasal pharynx may produce clinical signs indicating either respiratory
or swallowing disorders or a combination of both. Respiratory disorders may
result from pharyngeal or retropharyngeal masses, swelling, foreign bodies, or trauma.
Swallowing disorders rarely produce radiographic changes unless they are due to pharyngeal
masses.
A carefully positioned lateral view with the animal’s head and neck extended provides
the most useful information. Ventrodorsal and dorsoventral views are rarely helpful. Slight
rotation or flexion of the head and neck can produce artifactual increases in laryngeal
density and create an illusion of a soft-tissue mass. If the animal is swallowing at the time
of radiographic exposure, the normal pharyngeal airway may be artifactually eliminated.
Thus all abnormalities identified should be confirmed with a well-positioned, properly
exposed lateral radiograph (Fig. 2-214). Both pharyngeal and laryngeal abnormalities may
occur without apparent radiographic changes. Endoscopy should be performed regardless
of the radiographic findings if clinical signs indicate an abnormality in these areas.