CT/MRI

6-year-old female American Bulldog

Labored breathing and fever

History

The patient had labored breathing and fever (40.9C) since 3 days when she was presented at her regular veterinarian where thoracic radiographs were obtained. Thoracic radiographs showed left sided pleural effusion preventing expansion of the lung lobes almost completely on this side, with the cardiac silhouette being shifted to the right and proliferative lesion on the left third rib. 3 ml of pus were removed after thoracocenthesis.

The dog was referred for CT evaluation. On presentation was leukocytosis, nonregenerative anemia, and severe hypoalbuminemia.

2.5 mm thick slices of the thorax were acquired in a helical mode. Transverse images are displayed with the left side of the patient on the right side of the screen.

CT of the thorax, prior to contrast: soft tissue and bone windows
Note: left side of the patient is left on the image

Soft tissue window, delayed phase

On pre-contrast images, there is a large soft tissue attenuation occupying most of the left hemi-thorax with complete atelectasis of the left cranial lung lobe and partial atelectasis of the ventro-lateral aspect of the left caudal lung lobe. There is right sided displacement of the cardiac silhouette. There is widening and heterogeneity of the ventral half of the left third rib with a well defined rounded lytic lesion on the pleural surface of this rib. From this rib and extending to the caudal aspect of the thoracic cavity there is a well defined focal rounded soft tissue to mineral attenuation (180 HU) measuring 4 mm in diameter. There is also focal pleural thickening of the pleura on the right side and smooth periosteal reaction of the pleural side of several of the left ribs.

On post contrast images, there is essentially peripheral enhancement of the left thoracic cavity revealing a multilobulated mass and marked enhancement around the well defined focal soft tissue to mineral attenuation. There is enlargement and heterogeneous enhancement of the sternal, cranial mediastinal and tracheobronchial lymph nodes.

On the reformatted images, this soft tissue to mineral attenuation is continuous and linear measuring 15 cm long and resembling a wooden foreign body such as a teriyaki stick.

Summary

Left thoracic multilobulated abscesses secondary to a wooden foreign body with osteomyelitis of the third rib.

The dog went to surgery and a teriyaki stick was removed after partial ostectomy of the rib. A diffuse left pyothorax was present with multilobulated abscess. Scar tissue was identified on the diaphragm and the stick likely perforated the stomach and migrated through the thoracic cavity and was anchored within the rib.

A chest tube was placed. Expansion of the left lung lobes could not be recovered completely. Bacteriology : Corynebacterium spp.

The dog recovered without complication and left the hospital under the appropriate antibiotic therapy.

References

  1. Computed tomographic diagnosis of nongastrointestinal foreign bodies in dogs. Jones JC, Ober CP. J Am Anim Hosp Assoc. 2007 Mar-Apr; 43(2):99-111.
  2. Radiographic, computed tomographic, and ultrasonographic findings with migrating intrathoracic grass awns in dogs and cats. Ryan M Schultz, Allison Zwingenberger. Vet Radiol Ultrasound 2008 Vol 49 (3): 249-255.

Dorsal reconstruction

Left parasagittal reconstruction