The most common types of uroliths larger than 1 mm are readily visible and accurately measured in an in vitro setting mimicking the canine abdomen using digital radiography.

Abdominal radiography is an important diagnostic to detect uroliths. Cystine and urate uroliths were historically characterized as nonmineral opaque on survey radiographs. However, recent research and clinical observations indicate that pure urate and cystine uroliths may be detected with digital radiography. The primary purpose of this prospective, in vitro, diagnostic accuracy study was to determine the sensitivity of digital radiography in detecting cystoliths of varying size and composition. Forty canine uroliths of pure composition (10 each of calcium oxalate, struvite, cystine, and urate), acquired from Minnesota Urolith Center and ranging from 1 to 10 mm, were placed in phantoms of three various sizes and radiographed. The radiographs, including three sets of each urolith separately, were evaluated by three blinded radiologists on two separate occasions. Evaluation included presence or absence of urolith, number of uroliths, and maximum diameter of the urolith(s). For all four types of uroliths and all readers, the specificity and PPV were 100% with an associated very high sensitivity (94.4%-98.9%) and NPV (94.8%-98.9%). Calcium oxalate uroliths were the most accurately measured and struvite were the least accurately measured when compared with the gross measurement. Smaller uroliths were more accurately measured than larger uroliths. Uroliths placed in smaller bladder phantoms were more accurately measured than in larger bladder phantoms. Though accurate measurement of uroliths is complicated by and dependent on numerous variables, our results reveal that urate and cystine uroliths are visualized on digital radiography making them a relevant differential diagnosis when seen clinically.

Abdominal ultrasound and clinicopathologic findings in 22 cats with exocrine pancreatic insufficiency.

BACKGROUND: Awareness of exocrine pancreatic insufficiency (EPI) in cats has increased since the development of an assay for feline trypsin-like immunoreactivity (fTLI). Ultrasound findings in cats with EPI have only been reported rarely and described as nonspecific. HYPOTHESIS/OBJECTIVES: To describe the ultrasonographic findings, clinical signs, and concurrent diseases in cats with EPI. ANIMALS: Twenty-two client-owned cats with EPI. METHODS: Multicenter retrospective descriptive study including cats with serum fTLI concentration ≤8 µg/L and an abdominal ultrasound examination performed within 6 weeks of fTLI measurement. Sonographic measurements of maximal pancreatic thickness and maximal pancreatic duct diameter as well as ratios of pancreatic duct diameter to pancreatic thickness were obtained. Additional sonographic findings, concurrent conditions, and clinical signs were recorded. RESULTS: The most common clinical sign was weight loss (15/22 cats). Chronic enteropathy was the most common concurrent disease (13/22 cats). In 39% of cats, the pancreas had minimal or no sonographic alterations. Pancreatic duct dilatation (>2.5 mm), pancreatic duct tortuosity with variable diameter, or both were seen in 6/13 cats. The pancreatic parenchyma was subjectively thin in 6 cats. A significant relationship was found between subjectively thin pancreatic parenchyma and increased pancreatic duct size : pancreatic thickness ratio (P = .004). Diffuse gastrointestinal dilatation with echogenic content was observed in 8/22 cats. CONCLUSION: Exocrine pancreatic insufficiency often causes minimal to no sonographic pancreatic changes. Nonetheless, the findings of thin pancreatic parenchyma, pancreatic duct dilatation, or diffuse small intestinal dilatation with echogenic contents in cats with unexplained weight loss or unformed feces should raise clinical suspicion for EPI.

Imaging and clinical features of a true gastrogastric intussusception in a dog.

An 18-month-old male mixed breed dog was evaluated for acute vomiting and hematemesis. Clinical signs and initial radiographic findings shared commonalities with reported cases of pylorogastric intussusception in dogs. However, unlike previously reported cases, additional imaging [including ultrasound and computed tomography (CT)] revealed invagination of the gastric fundus into the gastric body, consistent with true gastrogastric intussusception. These findings were confirmed with histopathology and on necropsy. Key clinical message: Although extremely rare, gastrogastric intussusception should be included as a differential diagnosis for any patient presenting with acute vomiting, abdominal pain, dehydration, or tachycardia in combination with the diagnostic imaging findings described in this report.

Caractéristiques cliniques et d'imagerie d'une intussusception gastro-gastrique vraie chez un chien. Un chien mâle de race croisée âgé de 18 mois fut évalué pour des vomissements aigus et de l'hématémèse. Les signes cliniques et les trouvailles radiographiques initiales partageaient des similarités avec des cas rapportés d'intussusception pyloro-gastrique chez des chiens. Toutefois, contrairement aux cas rapportés précédemment, des examens d'imagerie supplémentaires [incluant l'échographie et la tomodensitométrie (CT)] ont révélé une invagination du fundus gastrique dans le corps de l'estomac, compatible avec une intussusception gastro-gastrique vraie. Ces données furent confirmées lors de l'examen histopathologique et de la nécropsie.Message clinique clé :Bien qu'extrêmement rare, l'intussusception gastro-gastrique devrait être incluse dans le diagnostic différentiel pour tout patient présenté avec des vomissements aigus, de la douleur abdominale, de la déshydratation ou de la tachycardie en combinaison avec les trouvailles en imagerie diagnostique décrites dans le présent rapport.(Traduit par Dr Serge Messier).

Magnetic Resonance Imaging Features of Extradural Spinal Neoplasia in 60 Dogs and Seven Cats.

This retrospective study describes the MRI features of extradural spinal neoplasia in 60 dogs and seven cats to identify potential distinguishing features between tumor classes and individual tumor types within each class. In dogs, mesenchymal tumors were most common (48%), with undifferentiated sarcomas being the predominant tumor type. Round cell neoplasms were second most common (35%), with lymphoma and multiple myeloma/plasma cell tumor comprising the majority of cases. Only two benign tumors were identified. In cats, lymphoma was most common (5/7), with one case of mesenchymal neoplasia and one case of metastatic carcinoma. Despite some overlap, certain imaging features were able to help prioritize differential diagnoses. The combined features that predicted round cell neoplasia (84%) included the preservation of vertebral shape, homogeneous contrast enhancement, and lesion centering on bone. The combined features that predicted mesenchymal neoplasia (73%) included altered vertebral shape, heterogeneous contrast enhancement, and lesion centering on paraspinal soft tissues. Round cell neoplasms were more likely to have cortical sparing, preservation of overall shape, lesion centering on bone, small soft tissue tumor size, and homogeneous contrast enhancement. Both epithelial and mesenchymal neoplasms were more likely to have cortical lysis, a cavitary component to the soft tissue mass and medium to large soft tissue mass size. The findings of this study can aid in prioritizing differential diagnoses in cases of extradural spinal neoplasia in cats and dogs, which can impact case management, but tissue sampling remains the gold standard for definitive diagnosis.

Administration of certain sedative drugs is associated with variation in sonographic and radiographic splenic size in healthy cats.

Ultrasonography and radiography are standard diagnostic tests for cats with suspected splenic disease, however published information on outside sources of variation are currently lacking. The purpose of this prospective, randomized, crossover group study was to evaluate effects of common sedative drugs on the sonographic and radiographic characteristics of the spleen in healthy cats. Fifteen healthy adult research cats were randomly assigned into one of three groups corresponding to different sequences of administration of five sedative drugs/drug combinations (acepromazine; butorphanol; dexmedetomidine; midazolam and butorphanol (MB); and dexmedetomidine, butorphanol, and ketamine (DBK)), administered at 1-week intervals. At each visit, three-view abdominal radiographic and ultrasonographic examinations were performed prior to sedation and repeated 15-30 min and 2-3 h post sedation. Two board-certified radiologists (one ACVR and one ACVR/ECVDI) evaluated the anonymized and randomized images. Acepromazine resulted in significantly increased sonographic and radiographic splenic measurements from baseline, which remained significantly increased 2-3 h post sedation. The mean magnitude of this change ranged from 0.9 mm (tail height, SD 1.4 mm) to 1.8 mm (body height, SD 1.7 mm) for ultrasound, and was 2.2 mm (ventrodorsal width, SD 2.3 mm) for radiographs. With butorphanol, there was no significant change in splenic size. For dexmedetomidine, MB, and DBK, there was a trend toward increased splenic size from baseline to the first post-sedation timepoint, which was statistically significant for radiographic measurements, although not for ultrasound. Findings indicated that acepromazine should be avoided prior to imaging while butorphanol may be used when sedation is needed in cats presenting for potential splenic disease.

Novel CT Features of an Abdominal Gossypiboma in a Female Dog.

CASE DESCRIPTION: An eight-year-old Golden Retriever was presented with hypercalcemia and a complex abdominal mass. CLINICAL FINDINGS: A well-defined, heterogeneously contrast-enhancing, cavitary, soft tissue attenuating, non-organ associated abdominal mass was identified caudal to the right kidney. This mass was confluent with the distal tip of the right limb of the pancreas. A connected large, rim enhancing, cystic subcutaneous mass was also present in the right lumbar subcutaneous tissues, and there were multiple fistulous tracts through the hypaxial musculature. TREATMENT AND OUTCOME: The dog underwent a surgical exploratory laparotomy and a gossypiboma was removed from the intra-abdominal mass; the cystic extra-abdominal mass was drained percutaneously. Surgical recovery was uneventful and a follow-up CT after 3 months was consistent with resolving granulomatous inflammation and fibrosis. CLINICAL RELEVANCE: The presence of multiple peripherally enhancing tracts extending from the abdominal mass through the hypaxial musculature is a CT feature which has not yet been described in the veterinary literature. Additionally, incorporation of the pancreas into the abdominal mass has also not yet been described in the veterinary literature.

Use of cystoscopic-guided laser ablation for treatment of unilateral ureterovesicular stenosis and secondary orthotopic ureterocele in a female dog.

CASE DESCRIPTION A 4-year-old spayed female Beagle was evaluated because of a 2-month history of intermittent pollakiuria, stranguria, dysuria, and abdominal pain. A diagnosis of bacterial cystitis was initially made, but clinical signs persisted despite appropriate antimicrobial treatment, so the dog was referred for further evaluation and treatment. CLINICAL FINDINGS Abdominal ultrasonography revealed a large, thin-walled, cystic structure in the urinary bladder at the level of the expected right ureterovesicular junction that communicated with the uniformly dilated right ureter. Severe right-sided pyelectasia was also detected. A presumptive diagnosis was made of a right-sided orthotopic ureterocele with secondary hydroureter and pyelectasia. TREATMENT AND OUTCOME Cystoscopy revealed a large cystic structure in the region of the right ureterovesicular junction without obvious communication between the ureter and urinary bladder. Portable C-arm fluoroscopy was used to confirm the presence of an intramural orthotopic tract and to measure the diameter of the ureter and renal pelvis via retrograde contrast ureteropyelography. Complete laser ablation of the ureterocele was performed by incising it circumferentially near its base. Clinical signs resolved immediately following the procedure. Six weeks later, the dog remained free of clinical signs and abdominal ultrasonography revealed resolution of hydroureter with persistence of mild right-sided pyelectasia. CLINICAL RELEVANCE Cystoscopic-guided laser ablation of an orthotopic ureterocele secondary to ureterovesicular stenosis was a safe and effective minimally invasive treatment for the dog of this report, resulting in immediate and continued improvement of clinical signs and ultrasonographic changes. Laser ablation should be considered as an alternative to surgery for the treatment of orthotopic ureteroceles in dogs.