Computed Tomography of the Mediastinum of the Dog by a Six‐generation CT Scanner, Different Windows and Peroral and Intravenous Contrast Medium

Abstract

The anatomical and clinical studies of computed tomography (CT) in the dog are still scarce. Particularly, there are few CT studies combining the use of rapid apparatus of the latest generation, the supply of contrast medium (digestive or intravenous) and the application of regional specific CT windows with different window width (WW) and window level (WL). The use of this CT methodology is particularly recommended in the evaluation of mediastinal masses, heart pathologies, etc. In this work the mediastinum of the dog was studied by using a sixth generation spiral CT scanner (Toshiba Ex Vision), belonging to the private Medical Institute of Radiology ‘Irion’ of Porto Alegre, Brazil. Four mixed‐breed mature dogs (4–6 years, 15–20 kg) were used, two males and two females. The dogs were anaesthetized and kept at a maximum inspiration when getting the images. Previously, the urografin® contrast had been injected by peroral and intravenous (cephalic vein) via. Dogs were placed in a stretcher in sternal recumbency. Different CT windows were applied in order to increase the quality of the images and to obtain detailed attenuation shades of the mediastinum organs: soft tissue window (WW 652; WL ‐34), pulmonary window (WW 928; WL ‐680) and mediastinal‐vascular window (WW 352; WL 220). The mediastinal space was studied craniocaudally from the level of the cranial cava vein, brachiocephalic trunk and left subclavian artery, to the caudal end of the lumbodiaphragmatic recess. The obtained images allowed a very good tomographic evidence of the great vessels, the heart, the thoracic portion of the trachea, the principal bronchi, the thoracic portion of the oesophagus, etc.