Radiographic and CT features of metallosis in a lame dog after total hip replacement: the cloud sign.

A 2-year-old female American Akita was referred for CT of the pelvis and hindlimbs due to a left hindlimb lameness after a left total hip replacement. Referral radiographs and CT images demonstrated amorphous soft-tissue and mineral opacities surrounding the proximal femur and the prosthetic stem, consistent with the "cloud sign" reported as a characteristic of metallosis in humans. Dorsomedial displacement of the prosthetic head, multiple foci of geographic osteolysis alongside the "cloud sign", presumed pseudotumor lesions, and medial iliac lymphadenopathy were also identified with CT. Metallosis was confirmed based on ultrasound-guided cytology, revision surgery, and histopathology.

Ultrasonographic and CT diagnosis of a complete splenic duplication with right splenic torsion and presumed regional splenic vein hypertension in a dog.

An 8-year-old mixed breed dog, was referred for lethargy, abdominal discomfort, hematemesis, and melena. Abdominal ultrasound revealed mineralization of the "right splenic vein" with collateral spiraling and a suspected splenic duplication. Computed tomography confirmed the duplication along with torsion of the splenic pedicle. Exploratory laparotomy confirmed the splenic torsion associated with congestion of the gastrointestinal vessels, indicative of a chronic onset of secondary regional splenic vein hypertension.

Spontaneous emphysematous splenitis: Radiographic and ultrasonographic findings in three Golden Retriever dogs.

Spontaneous emphysematous splenitis is a life-threatening condition reported rarely in humans; however, published reports in dogs are currently lacking. The aim of this multicentric, retrospective, case series design study was to describe radiographic and ultrasonographic imaging findings in Golden Retriever dogs diagnosed with spontaneous emphysematous splenitis. A total of three dogs were sampled. All dogs had a history of lethargy, diarrhea, and weight loss. Radiographic findings in all dogs included a mass effect with focal or multifocal coalescing "vesicular-like" gas pattern in the splenic region and focal loss of serosal detail. Ultrasonographic findings in all dogs included focal or multifocal irregularly shaped, hypoechoic areas containing a mixture of hyperechoic fluid and gas within the splenic parenchyma, hyperechoic abdominal free fluid, and generalized hyperechoic mesenteric fat without evidence of splenic torsion. Pneumoperitoneum was detected ultrasonographically and radiographically in two dogs. All three dogs underwent splenectomy and splenic torsion was definitively ruled out at surgery. One dog died three days after surgery, whereas the other two dogs recovered uneventfully. Culture of the splenic tissue and free abdominal fluid was positive for Clostridium spp. in all three cases. Findings supported inclusion of spontaneous emphysematous splenitis and septic peritonitis as differential diagnoses for dogs with this combination of clinical and imaging characteristics.

CT findings of an incidental segmental aplasia of the caudal vena cava with azygos continuation in a guinea pig (Cavia porcellus).

Background: Segmental aplasia of the caudal vena cava (CVC) with azygos continuation is a congenital malformation macroscopically described in mammals including humans, dogs, and rodents. It is usually detected as an incidental finding and the final diagnosis is reached by computed tomography (CT), fluoroscopy, or post-mortem dissection. Case Description: A 3-year-old guinea pig (Cavia porcellus) presented with subacute dyspnea. A computed tomographic examination was performed for the evaluation of subtle pulmonary changes previously suspected on conventional radiography, and a segmental aplasia of the CVC with azygos continuation was identified as an incidental finding. Conclusion: According to database negative results, this is the first report describing a segmental aplasia of the CVC and azygos continuation in a guinea pig by CT.