Parenchymal Patterns

Caudodorsal Parenchymal Pattern

This test is used to characterize a specific distribution of lung pathology observed on thoracic radiographs. It refers to an abnormal increase in lung opacity that is predominantly located in the caudal and dorsal regions of the lungs. Several underlying diseases can lead to a caudodorsal parenchymal pattern in dogs and cats, including pulmonary edema, contusions, atelectasis or pneumonia.
 

The caudal and dorsal lung lobes are considered normal if;

• Small vessels detail is adequate in the caudal and dorsal portion of the lungs.

• Canine cardiomegaly or left atrial enlargement is present, however, there is no increase in opacity noted in the caudal and dorsal lung lobes i.e. no concern for pulmonary edema - the vessels in the perihilar region are clearly visible, the outline of the cardiac silhouette/left atrium is crisp/clear.

The caudal and dorsal lung lobes are considered abnormal if;

• Air bronchogram are present - air-filled bronchi on a background of increased opacity or airless lung is visible.

• Lobar sign is present - increased opacity extends to periphery of lung lobe, and stops abruptly, leaving a dramatic transition between abnormal lobe border and adjacent normal lung lobe

• Increased opacity with border effacement of the small vessels is present - detail of the small vessels is lost due to the presence of an increased opacity within the caudal and dorsal lung lobe.

• Significant pleural effusion is present causing collapse of the cranial and dorsal lung lobe.

• Significant pleural gas is present causing collapse of the cranial and dorsal lung lobe.

• Canine cardiomegaly and/or left atrial enlargement is present, and the vessels and/or outline of the left atrium are starting to become blurry or hazy raising concern for the presence of pulmonary edema.

• Canine cardiomegaly and/or left atrial enlargement is present, and the vessels are not visible in the perihilar region that suggests the presence of pulmonary edema.