Computed Tomographic Evaluation of Canine and Feline Mediastinal Masses in 14 Patients

Abstract

A 15-year retrospective analysis of histologically proven canine and feline mediastinal malignancies at the University of Minnesota was conducted to identify patients imaged by computed tomography (CT). The goal of the study was to characterize the CT appearance, to determine if there were any tumor type-specific appearances, and to clarify the role of CT in patients with mediastinal masses. Fourteen patients meeting these criteria were available for evaluation. The masses were characterized based on the presence or absence of contrast enhancement, internal architecture, size, extent of local invasion, the presence of pleural fluid, and the presence of regional vascular invasion. Within the limits of this study and the histopathologic information available, there appeared to be no clinically exploitable relationship between the CT appearance and the histologic characterization of the mass. However, CT does provide reasonably accurate local staging information.

Imaging Evaluation of the Small Animal Mediastinum

“…In particular, the characterization of the masses, based on the presence or absence of contrast enhancement, internal architecture, size, extent of local invasion, and the presence of pleural fluid and regional vascular invasion, provides reasonably accurate local staging information (Burk, 1991;Henniger, 2003;Yoon et al, 2004).…”

“…Thoracic CT is also gaining more attention in small animal medicine as therapeutic possibilities increase (Henninger, 2003). In particular, the staging of mediastinal masses and the evaluation of invasiveness of lesions is critical when considering surgical intervention, chemotherapy or radiation (Yoon et al, 2004). The role of thoracic CT in the assessment of mediastinal masses is to provide a very detailed anatomical analysis of the mediastinal structures defining the location, size, number of masses, attenuation characteristics, contrast enhancement, and eventually any associated extramediastinal abnormality (Yoon et al, 2004).…”

“…In particular, the staging of mediastinal masses and the evaluation of invasiveness of lesions is critical when considering surgical intervention, chemotherapy or radiation (Yoon et al, 2004). The role of thoracic CT in the assessment of mediastinal masses is to provide a very detailed anatomical analysis of the mediastinal structures defining the location, size, number of masses, attenuation characteristics, contrast enhancement, and eventually any associated extramediastinal abnormality (Yoon et al, 2004). The major advantages of CT over standard thoracic radiography include better contrast discrimination, which allows distinction between solid, fatty, cystic, calcified, and vascular structures, and the cross-sectional image format that eliminates the superimposition problem of mediastinal structures.…”

Dynamic computed tomographic determination of scan delay for use in performing cardiac angiography in clinically normal dogs

“…[1][2][3][4][5] The main goal of CT angiography is to facilitate detection of pathological changes in the cardiovascular system by providing adequate and prolonged contrast enhancement within an anatomic ROI. 6,7 The quality of contrast enhancement achieved is influenced by contrast medium-related factors (eg, concentration, volume, injection rate, injection bolus protocol, and whether a flush solution is used), patient-related factors (eg, cardiac output, cardiovascular Dynamic computed tomographic determination of scan delay for use in performing cardiac angiography in clinically normal dogs OBJECTIVE To determine the scan delay for use in performing cardiac CT angiography in dogs.…”

Clinical and Histopathological Features of a Thymolipoma in a Dog

“…Effusion could result from increased thoracic duct pressure, secondary to compression of the cranial vena cava or thoracic duct by the thymolipoma, as suggested for mediastinal lymphoma and thymoma. [1][2][3]5,12 The mediastinal location of most thymolipomas, the soft and malleable nature of these lesions, and the semisolid consistency of fat at body temperature contribute to the ability of these tumors to conform to the shape of adjacent mediastinal structures. These properties might cause the mass to resemble cardiomegaly on frontal chest radiographs.…”