This study presents a comparative analysis of the computed tomographic (CT), radiographic, and ultrasonographic (US) characteristics of gastrointestinal foreign bodies, including bezoars, in dogs and cats, and evaluates their association with complications and clinical outcomes. A total of 33 cases (26 dogs, 7 cats) with surgically or endoscopically confirmed foreign bodies were reviewed, classified as bezoars (n = 15) or distinct foreign bodies (n = 18). CT features such as attenuation values, transition zones, and proximal-to-distal small intestinal diameter ratios were compared. Bezoars typically appeared as intraluminal masses with mottled gas patterns and indistinct boundaries (33.3% vs. 94.4%, p < 0.001) and were associated with longer clinical signs (median 14 vs. 5.5 days, p = 0.013), more frequent transition zones (92.3% vs. 41.7%, p = 0.011), and a greater diameter ratio (2.9 vs. 1.25, p = 0.012) across the transition zone. Radiographic and US evaluations were available in six bezoar cases; only one radiograph (17%) detected the bezoar, while US showed acoustic shadowing in four cases (67%). Six patients (18%) experienced adverse outcomes, with bowel wall ruptures significantly associated with poor prognosis (p < 0.001). These findings highlight the superior diagnostic performance of CT, particularly for bezoars, and emphasize the importance of identifying transition zones and bowel diameter ratios in assessing gastrointestinal foreign bodies and their associated risks. Early CT evaluation may thus facilitate timely intervention and improve clinical outcomes.

The objective of the present case series was to investigate the various computed tomography findings of six dogs diagnosed with extraskeletal osteosarcoma (exOSA) at several locations. Among the tumors evaluated, four were subcutaneous, one was mammary, and one involved the intestinal tract. Intralesional mineralization was observed in all six dogs. Most of the tumors were moderately calcified, exhibited amorphous mineralization, and were heterogeneous on post-contrast imaging. Three of the tumors were peripherally enhanced, and regional lymphadenopathy was identified in two of the dogs, which was presumed to be metastatic. No lymph node calcification was reported. Although the presence of intralesional mineralization is not a pathognomonic finding, it was consistently identified in the present case series. Therefore, exOSA should be considered in the differential diagnosis when mineralization occurs in a mass unrelated to osseous structures.