Small Animal Radiology and Ultrasound: A Diagnostic Atlas and Text

114 Small Animal Radiolo g y and Ultrasono graphy
Fig. 2-90 A 13-year-old male
Poodle with a 6-month history of
chronic nonproductive cough. A, On
the lateral thoracic view, there is a
soft-tissue density superimposed on
the tracheal shadow in the caudal
cervical region extending into the
thoracic inlet (arrows). This creates
an impression of tracheal collapse. B,
On a skyline projection of the trachea
the lumen appears normal.
There is slight indentation of the
dorsal trachea (arrows). An esophagram
was performed (C). The position
of the esophagus can be seen
overlying the trachea. Diagnosis:
Normal trachea with no evidence of
tracheal collapse.
A
B
C
a dynamic (fluoroscopic) contrast examination. Cineradiography or videotape with slow
motion and reverse capabilities is necessary to record and completely evaluate the separate,
rapidly occurring phases of swallowing.
Ultrasonography is rarely useful in the evaluation of the intrathoracic esophagus. The
cervical esophagus may be identified dorsal to, or left and lateral to, the trachea. The hyperechoic
gas and mucus within the lumen help identify the esophagus.