Атлас по рентгенологии травмированных собак и кошек / an-atlas-of-radiology-of-the-traumatized-dog-and-cat

92 Radiology of Thoracic Trauma

Case 2.41

Signalment/History: “Tuffy” was a 1-year-old, male, mixed-breed dog, whose the owner thought he had been

kicked by a horse.

2

Physical examination: While the dog’s temperature was normal, breathing was restricted and he was comfortable only when standing. Heart sounds could not be detected on the left side.

Radiographic procedure: Studies were made of the thorax.

Radiographic diagnosis: The diaphragm could not be identified on the left side on the DV view and was positioned cranially on the left side on the lateral view. Both of these positionings were suggestive of diaphragmatic hernia. Ingesta or fecal material within the thoracic cavity on the left supported this diagnosis. A portion of the right hemidiaphragm was identified in its normal position, suggesting injury to the left side only. The cardiac silhouette and the hilus were shifted to the right with malposition of the main-stem bronchus to the left caudal lobe; both suggestive of a mass lesion. Prominent airbronchogram patterns were noted indicative of alveolar flooding. Minimal pleural fluid was more prominent on the left side of the thorax. The liver shadow was difficult to localize.

Treatment/Management: The diaphragmatic hernia was characterized by several radiographic features. Mediastinal shift could be detected by locating the region of the tracheal bifurcation and the main-stem bronchi. Elevation of the tracheal shadow resulted from lateral shifting of the heart. Uneven distribution of pleural fluid is common with a diaphragmatic hernia and often reflects the degree of lung lobe collapse.

Comments: In the young patient, the pattern of calcification of the costal cartilages is rather orderly.

Diaphragmatic hernia 93

Case 2.42

Signalment/History: A 3-year-old, male DSH cat was presented with a history of trauma that had occurred 10 days ear-

lier.

2

Physical examination: The cat was depressed and slightly dyspneic on presentation.

Radiographic procedure: The whole body was included in the study.

Radiographic diagnosis: Small bowel loops occupied most of the right hemithorax with a mediastinal shift to the left. The air-filled stomach remained within the abdomen, but was shifted to the midline with the pylorus displaced ventrally and cranially. No evidence of chest wall injury was noted. A caudal displacement of the dorsal portion of the diaphragm could be seen.

Treatment/Management: The diaphragmatic tear extended from the sternal attachment 5 cm to the right. All of the small bowel, liver, and spleen were within the right hemithorax. The liver had a 360° twist around its pedicle and was incarcerated. The cat survived the surgery and was released to his owner.

94 Radiology of Thoracic Trauma

Case 2.43

2

Signalment/History: “Kitten” was a 10-month-old, female mixed breed cat with a history of dyspnea lasting for several months. The owners suspected that the cat had been traumatized six months previously.

Physical examination: Lung sounds were abnormal and the abdomen palpated empty.

Radiographic procedure: Whole body radiographs were made.

Radiographic diagnosis (thorax): A number of intrathoracic masses were present, some with uniform fluid density and others that included air. The cardiac silhouette was shifted dorsally along with the trachea. The diaphragm could not be identified ventrally or on the right side. The lungs were atelectic.

Diaphragmatic hernia 95

2

Radiographic diagnosis (abdomen): A large fluid density mass with a scattered mineralized pattern occupied the ventral midabdomen. The ingesta-filled stomach was crowded cranially and ventrally. Air-filled bowel extended cranially on the right into the thoracic cavity.

Comments: The dyspnea caused by the diaphragmatic hernia had been made more severe by the progressive increase in the size of the cat’s gravid uterus.

96 Radiology of Thoracic Trauma

Case 2.44

2

Diaphragmatic hernia 97

2

Signalment/History: “Menace” was a 6-year-old, male DSH cat with a two-month history of dyspnea, anorexia, and depression. The differential diagnosis included thymic lymphosarcoma.

Physical examination: The examination did not contribute anything to the evaluation of the case.

Radiographic procedure: The thorax was studied because of the tentative diagnosis of lymphosarcoma. An additional single lateral view of the abdomen was made.

Radiographic diagnosis: The thorax was expanded to maximum size. The pleural space was filled with air-containing viscera. The trachea was shifted to the left. The cardiac silhouette was in the left hemithorax. The diaphragm was located caudally, but could not be visualized on the ventral midline.

The single lateral view of the abdomen showed an absence of small bowel shadows.

Treatment/Management: The diaphragmatic hernia was confirmed by surgical exploration of the abdomen. Primary pulmonary disease was not considered on these radiographs because the atelectasis was thought to be caused by the pleural masses. Both pneumothorax and pneumomediastinum were present the day following surgery. Radiographs made three days post-surgery showed a minimal persistent pneumothorax; however, the lungs were expanded and of normal density.

Comments: Failure to identify the abdominal organs in their normal location often suggests their displacement into the thoracic cavity and diagnosis of a diaphragmatic hernia.

98 Radiology of Thoracic Trauma

Case 2.45

Signalment/History: “Trouble” was a stray 1-year-old, male DSH cat who was presented with a history of rapid

breathing for the previous five days.

2

Physical examination: Little could be learned from the examination. The thoracic wall was intact; however, injury was suspected on palpation of the costal cartilages. The heart and lung sounds could not be auscultated on the right. Cardiac sounds were stronger on the left.

Radiographic procedure: Radiographs of the thorax were made.

Radiographic diagnosis: An intrathoracic mass on the right side caused a mediastinal shift to the left and an elevation of the trachea. The heart was in contact with the left thoracic wall. The lung lobes appeared to be displaced dorsally. In the right hemithorax, the lung margins were retracted from the chest wall. A partial diaphragmatic shadow could be identified dorsally on the lateral view. The presence of a pleural mass was thought to be the cause of the retraction of the lung lobes and the mediastinal shift. Pleural fluid was thought probable. No thoracic wall injury was noted except for fractures of the caudal costal arches. The gastric shadow was shifted cranially to lie adjacent to the diaphragm, but remained within the abdominal cavity. The tentative diagnosis was a diaphragmatic hernia.

Treatment/Management: “Trouble” was successfully operated for the hernia.

Comments: While a thoracic mass other than a pleural mass resulting from a diaphragmatic hernia was possible in this patient, it was unlikely considering the age, clinical history, and the pres-

ence of the costal arch fractures.

Diaphragmatic hernia 99

Case 2.46

Signalment/History: “Siri” was a 3-year-old, female Siamese with a history of presumed trauma according to her

owner. She was known to have bilateral hip dysplasia.

2

Radiographic procedure: “Whole-body” radiographs were made because of the unknown nature of the injury and the small size of the patient.

Radiographic diagnosis: Cranial displacement of the right hemidiaphragm was matched by a caudal displacement of the left hemidiaphragm. More important in the diagnosis of a diaphragmatic hernia was the cranial displacement of the airfilled pyloric antrum. The heart was shifted into the left hemithorax. Minimal pleural fluid was trapped around the heart and the ventral mediastinum. A minimal increase in right middle lobe density suggested pulmonary hemorrhage secondary to trauma. No sign of chest wall trauma was noted.

Treatment/Management: The diagnosis of a diaphragmatic hernia was suggested by the shift in position of the air-filled abdominal organs, the asymmetry of the crura of the diaphragm, and the inability to see the cupula of the diaphragm. The patient was thin with little contrast between her abdominal organs because of the lack of fat, which suggested that the injury may have been long-standing. The radiographic diagnosis of a hernia is much more difficult in a patient in which a hollow viscus is not displaced. The hernia was proven surgically.

Whole body radiographs should include the thoracic inlet and the pelvic canal. These were cropped for publication.

100 Radiology of Thoracic Trauma

Case 2.47

2

Signalment/History: “Dale” was a 1-year-old, male

Siamese with a chronic cough of two months duration.

Radiographic procedure: Thoracic radiographs were made to evaluate the cause of the coughing. The history did not suggest a traumatic etiology.

Radiographic diagnosis: Radiodense material having the appearance of small bone fragments was located within the central portion of the thoracic cavity caudally. The mass was lobulated and surrounded by pleural fluid that caused silhouetting with the diaphragm ventrally. The mass effect elevated the trachea dorsally. The heart was difficult to visualize, but a shadow typical for the heart was displaced dorsally. The bony fragments were treated as a contrast agent enabling the location of the displaced gastric shadow.

Treatment/Management: The diaphragmatic hernia was repaired successfully. The cause for the hernia or the time of the injury was not determined.

Diaphragmatic hernia 101

Case 2.48

2

Signalment/History: “Jazabelle”, a 3-year-old, female DSH cat, was depressed without any clinical history of trauma.

Physical examination: The clinical examination was unremarkable except for the failure to auscultate lung sounds on the caudal right side.

Radiographic procedure: Radiographic views of the thorax were made.

Radiographic diagnosis: A mass effect was created in the caudal right thorax silhouetting with the diaphragm and displacing the heart markedly to the left. Air-filled bowel loops were present within the mass. If pleural fluid was present, it seemed to be trapped on the right side caudally. Stomach air could not be identified in its normal position within the abdomen. A congenital anomaly affecting the xiphoid was present; a type rather common in the feline.

Comments: Many pulmonary lesions can become consolidated and cause trapped pleural effusion, however, major bronchi should be at least partially identifiable throughout the mass. In this cat, the trachea was shifted to the left and no airway shadows could be seen within the mass. The large air shadow extending from the cranial abdomen to the right hemithorax was indicative of small bowel and confirmed the diagnosis of a diaphragmatic hernia.