Radiography provides a rapid, noninvasive mechanism for evaluating structures within and surrounding the thorax. Because the changes seen on thoracic radiographs are often indicative of systemic disease (and may be nonspecific), the clinician needs to keep the patient, signalment, physical examination, and other laboratory findings in mind when prioritizing the differential diagnoses.

Considerations

Interpretation of thoracic radiographs can be challenging because most disease processes often involve several areas of the thorax. Thoracic radiographs may be followed by a thoracic computed tomographic study to better characterize or understand the thoracic roentgen abnormalities seen.

High-quality, 3-view thoracic films that are correctly positioned should be the starting point for all practitioners. For best results, the practitioner should be actively involved in processing the images to ensure correct anatomical positioning and exposure (Figure 1). Whenever possible, more than 1 person should review films for abnormalities and roentgen changes.

Figure 1

Expiratory (A) and inspiratory (B) right lateral radiographs from a 7-year-old neutered male poodle. Because the act of respiration changes the thoracic appearance, inspiratory films should be attempted to distinguish artifacts from true lung pathology.