Cooled feline intestine and fresh intestine did not differ in enterotomy leak pressure testing or in gross wall thickness measurement.

OBJECTIVE: To report gross anatomical gastrointestinal measurements and compare enterotomy leak pressures between fresh and cooled feline cadavers. STUDY DESIGN: Ex vivo, randomized study. ANIMALS: Fresh feline cadavers (n = 20). METHODS: Jejunal segments (8 cm) were harvested on the same day as euthanasia. From each cadaver, one segment was randomly assigned to control (C), fresh enterotomy (FE), and cooled enterotomy (CE) groups. Enterotomy construction and leak testing were performed within 12 h of euthanasia for the C and FE groups and after 17-29 h of cooling for the CE group. Initial leak pressure (ILP) and maximum intraluminal pressure (MIP) were compared. Gastrointestinal wall thickness and intraluminal diameter were measured on harvested applicable gastrointestinal divisions at up to three time points: day 1 fresh, day 2 cooled, and day 3 cooled. RESULTS: The mean (± SD) ILPs for the C, FE, and CE constructs were 600 (± 0.0), 200.3 (± 114.7), and 131.3 (± 92.6) mmHg, respectively. The C ILP was higher (p < .001) than the FE and CE ILP. The ILP (p = .11) and the MIP (p = .21) did not differ between the FE and CE constructs. Wall thickness (measured in mm) did not differ between duodenum day 1 fresh and day 2 cooled groups (p = .18) or between any jejunum day groups (p = .86). The intraluminal diameters (mean ± SD) for the duodenum, jejunum, and ileum were 5.7 (± 0.7), 5.8 (± 0.8), and 7.2 (± 2.2) mm, respectively. CONCLUSION: No difference was appreciated between FE and CE ILP and MIP. Wall thickness measurements did not differ between days for duodenum or jejunum. CLINICAL RELEVANCE: Cadaveric feline intestine cooled for up to 29 h may be used for determining intestinal leak pressures.

Hepatic insufficiency in two juvenile dogs with histoplasmosis.

A 9-month-old female intact toy poodle and a 1-year-old female intact Labrador retriever mix presented to separate teaching hospitals for chronic histories of malaise and clinicopathologic evidence of hepatic dysfunction. The signalment and clinical histories of these dogs prompted consideration of a congenital portosystemic shunt as a primary differential. However, microscopic evaluation of peritoneal effusion, pleural effusion, and peripheral blood samples from the dogs revealed round to ovoid yeast organisms morphologically most compatible with Histoplasma capsulatum. Additional testing confirmed histoplasmosis in each case. The poodle underwent a computed tomography (CT) study, which showed hepatomegaly with a spleno-gonadal shunt, pancreatic and gastric wall edema, and marked peritoneal effusion, findings compatible with portal hypertension and secondary acquired shunt formation. The dog was later humanely euthanized due to clinical deterioration, and on necropsy hepatic histoplasmosis was verified, with additional affected tissues comprising lungs and spleen. The Labrador Retriever mix responded clinically and clinicopathologically to antifungal therapy, though no abdominal imaging was performed to definitively exclude the possibility of a congenital portosystemic shunt. In retrospect, several features were more compatible with histoplasmosis than portosystemic shunt in these cases, including hyperbilirubinemia, effusion, and hepatomegaly. These findings serve as a reminder of the need to interpret serum biochemical findings in the context of the totality of the clinicopathologic data and imaging findings, as well as the diagnostic value of microscopy in the evaluation of hematologic and body cavity fluid samples.

Computed tomographic characteristics of confirmed and presumed noncutaneous pythiosis in 25 dogs.

Pythium insidiosum is an aquatic oomycete that causes granulomatous infection in dogs, most commonly cutaneous and gastrointestinal. Ultrasonographic characteristics of gastrointestinal pythiosis have been described; occasionally, CT is utilized in the clinical setting, and CT features of pythiosis have not been published. The purpose of this retrospective, multicenter, descriptive study is to describe CT characteristics of noncutaneous canine pythiosis. The following CT parameters were recorded: lesion anatomic location, number, shape, margination, size, attenuation pre- and postcontrast, enhancement pattern, lymph nodes affected, other lesions identified, and presence of peritoneal effusion or steatitis. Descriptive statistics demonstrating the frequency of lesion appearances were performed. Twenty-five dogs with noncutaneous pythiosis lesions that underwent CT were included; 19 had primarily gastrointestinal infections, four primarily arterial infections, one intrathoracic and intra-abdominal infection, and one primary pulmonary infection. In dogs with primary gastrointestinal infection, lesions were most common at the ileocolic junction and were most frequently focal, well-defined, moderate to marked circumferential wall thickening that was homogeneous and smoothly marginated precontrast, with moderate heterogeneous contrast enhancement. Most dogs had involvement of multiple gastrointestinal regions. Of four dogs with primary arterial involvement, three had large aneurysmal dilatations of the cranial mesenteric artery with severe mural thickening. All dogs had regional lymphadenopathy, which was variable but generally mild. Nine dogs had peritoneal effusion; six dogs had steatitis. CT features of pythiosis can overlap with neoplasia, but pythiosis should be considered as a differential, especially in young dogs. Findings supported using CT as an adjunct imaging test for increasing clinical suspicion of noncutaneous pythiosis.

Laparoscopic ultrasonography of the liver is feasible and safe in dogs.

OBJECTIVE: To describe the feasibility and technique for performing laparoscopic ultrasound (LUS) of the liver in dogs. ANIMALS: 12 client-owned dogs presenting for elective laparoscopic surgery from January 1, 2022, to October 31, 2022. METHODS: Laparoscopic exploration and LUS of the liver were performed in all dogs. Dogs were positioned in reverse Trendelenburg and laterally rotated to facilitate access to all liver lobes. Time to perform laparoscopic exploration and LUS, ability to visualize and access each liver lobe entirely, and any complications were recorded. Each dog underwent an elective laparoscopic procedure. The surgeon completed a National Aeronautics and Space Administration Task Load Index (NASA-TLX) questionnaire after surgery. RESULTS: Mean body weight was 25.9 kg (SD, ± 4.1 kg; range, 5.7 to 62 kg). All liver lobes were scanned to the level of the hilus in 10/12 dogs. In 2 dogs, the caudate lobe could not be completely imaged. Median time to perform LUS was 9 minutes (IQR, 5 to 16.5 minutes), and median NASA-TLX score was 9/100 (IQR, 6.3 to 20). There was a significantly strong negative correlation between time to perform LUS (r = -0.77; P = .0037) and NASA-TLX score (r = -0.84; P = .0006) with trial number. Minor complications occurred in 2 dogs during laparoscopic exploration. No complications occurred during LUS. CLINICAL RELEVANCE: LUS was feasible and safe in all dogs. The right lateral and caudate lobes were occasionally challenging to access. Technical demand and time to perform LUS improved with experience, suggesting a learning curve. Evaluation of LUS in dogs with clinical disease is warranted.

A Novel Standardized Method for Aiding to Determine Left Atrial Enlargement on Lateral Thoracic Radiographs in Dogs.

BACKGROUND: Left atrial enlargement indicates severe cardiac disease. Although the gold standard for determining left atrial size is echocardiography, many veterinary practices lack the necessary equipment and expertise. Therefore, thoracic radiography is often used to differentiate cardiogenic pulmonary edema from primary respiratory diseases and to facilitate distinguishing dogs with stage B1 and B2 mitral valve degeneration. METHODS: The goal was to test a new standardized method for identifying radiographic left atrial enlargement. On a lateral radiograph, a straight line was drawn from the dorsal border of the tracheal bifurcation to the crossing point of the dorsal border of the caudal vena cava and the most cranial crus of the diaphragm. If a part of the left atrium extended this line dorsally, it was considered enlarged. Echocardiographic left atrial to aortic ratio (LA:Ao) was used as a reference. Thirty-nine observers with various levels of experience evaluated 90 radiographs, first subjectively, then applying the new method. RESULTS: The new method moderately correlated with LA:Ao (r = 0.56-0.66) in all groups. The diagnostic accuracy (72-74%) of the subjective assessment and the new method showed no difference. CONCLUSIONS: Though the new method was not superior to subjective assessment, it may facilitate learning and subjective interpretation.

Radiographic and ultrasonographic appearance of a jejunal torsion-volvulus in a dog.

A 1.5-year-old male neutered, 5 kg, Dachshund was referred for anorexia and vomiting for several days' duration. Radiographs revealed concern for a small intestinal obstruction. Ultrasonography revealed a severely distended segment of jejunum containing echogenic fluid that abruptly narrowed, twisted, and transitioned into normal jejunum, along with the presence of a distinct "whirl sign" that resulted from the intestinal segments twisting around themselves. This, in addition to the absence of flow on power Doppler interrogation, was compatible with a focal jejunal torsion-volvulus. The torsion-volvulus was surgically confirmed, a resection and anastomosis was performed, and the dog recovered uneventfully.

Computed tomographic features of double aortic arch in six dogs.

Double aortic arch (DAA) is a rare, congenital anomaly in small animals, resulting in a complete vascular ring encircling the esophagus and trachea, and subsequent compression of these organs. Few studies have reported utilizing CT angiography (CTA) for diagnosing DAA in dogs; thus, the imaging features are currently lacking in the literature. The objectives of this retrospective, multicenter, descriptive case series were to report the clinical and CTA characteristics of DAA in surgically treated cases. Medical records and CTA images were reviewed. Six juvenile dogs met the inclusion criteria (median age: 4.2 months; range: 2-5 months). The most common clinical signs included chronic regurgitation (100%), decreased body condition (67%), and coughing (50%). Common CTA features of DAA included a dominant left aortic arch (median diameter: 8.1 mm) and minor right aortic arch (median diameter: 4.3 mm; 83%), an aberrant right subclavian artery arising directly from the right aortic arch (83%), segmental esophageal constriction (100%), and variable degrees of dilation cranial to the heart base, and marked tracheal luminal compression (median percent change: -55%; 100%) and leftward curvature of the trachea at the level of the bifurcation of the aortic arches (100%). All dogs underwent successful surgical correction with only minor postoperative complications. Due to the similarity of clinical and imaging characteristics described to that of other forms of vascular ring anomalies (VRA), CTA is vital for the specific diagnosis of DAA in dogs.

Percutaneous transvenous coil embolization of an extrahepatic portosystemic shunt in a cat.

Case summary: A 10-month-old male domestic shorthair cat presented for surgical treatment of a congenital portosystemic shunt. The cat had a history of lethargy and ptyalism. Pre- and postprandial bile acids were markedly elevated. CT was performed, which revealed a single, congenital, left gastrophrenic, extrahepatic portosystemic shunt. A minimally invasive surgical approach was considered by transjugular percutaneous coil embolization of the venous shunt, which was performed without complications. Follow-up protein C and serum biochemical analyses were performed at 1, 2 and 5 months postoperatively, and were improved. The cat is alive and clinically normal 11 months postoperatively. Relevance and novel information: This is the first report of percutaneous transvenous coil embolization for the treatment of an extrahepatic portosystemic shunt in a cat. The outcome was excellent in this patient, with no complications and complete resolution of clinical signs.

Percutaneous transvenous coil embolization of congenital intrahepatic portosystemic shunts in small- and toy-breed dogs: 20 cases (2015-2021).

OBJECTIVE: To describe outcomes of small- and toy-breed dogs with a congenital intrahepatic portosystemic shunt (IHPSS) treated with percutaneous transvenous coil embolization (PTCE). ANIMALS: 20 small- and toy-breed dogs with an IHPSS. PROCEDURES: All dogs underwent CT angiography for shunt evaluation as well as PTCE. Medical records were reviewed for pertinent data, and owners and primary veterinarians were contacted for long-term follow-up information. RESULTS: Dogs ranged from 1.5 to 10.0 kg (mean ± SD, 6.32 ± 2.57 kg) in weight. The equipment used to perform PTCE tended to be smaller than that previously described for larger breed dogs. Intra- and postoperative complication rates were 20% (4/20) and 5% (1/20), respectively, and included hypotension, bradycardia, hypercapnia, ventricular premature contractions, hypothermia, and regurgitation. Dogs were discharged a median of 3 days (range, 1 to 3 days) after surgery, and all dogs survived to discharge. Clinical signs resolved in 95% (19/20) of the dogs a median of 21 days after the procedure. One- and 2-year survival rates were 92%. Three dogs had died by the time of data collection; 2 of these dogs died of causes related to the IHPSS 267 and 1,178 days, respectively, after the procedure. CLINICAL RELEVANCE: Percutaneous transvenous coil embolization was a safe and effective option for treatment of IHPSS in small- and toy-breed dogs and offered a minimally invasive alternative to open surgical techniques. Complication and survival rates in this cohort were similar to or better than those reported in previous studies evaluating PTCE and open surgical techniques for treatment of IHPSS in dogs.

Prospective evaluation of lymphatic embolization as part of the treatment in dogs with presumptive idiopathic chylothorax.

OBJECTIVE: To describe the embolization technique and short-term clinical outcome in dogs undergoing lymphatic embolization (LE) as part of treatment for presumptive idiopathic chylothorax (IC). Additionally, to document findings in computed tomography lymphangiography (CTLa) following embolization. STUDY DESIGN: Prospective case series. ANIMALS: Eight client-owned dogs. METHODS: Dogs underwent CTLa followed by thoracic duct ligation (TDL), pericardiectomy (PC) and LE. A mixture of 3:1 lipiodol: n-butyl cyanoacrylate embolic solution was injected through a catheterized mesenteric lymphatic vessel via limited abdominal approach using intraoperative fluoroscopy. CTLa was scheduled for 12 weeks postoperatively, and long-term follow-up was obtained via telephone contact. RESULTS: LE was technically successful in six of the eight dogs; and clinically successful in five of the six dogs. In the unsuccessful dog, a diagnosis of lymphangiosarcoma was determined, and the owners elected for euthanasia. Five dogs who underwent successful LE underwent CTLa at 12 weeks. Complete resolution of pleural effusion occurred in three dogs and scant pleural effusion in two dogs. A robust lymphatic embolus preventing antegrade continuation of radiocontrast was documented in all five dogs. Five of the six dogs that underwent LE, were alive and clinically normal at 358-960 days postoperatively. CONCLUSIONS: LE is a feasible part of treatment for dogs with IC. Additionally, a robust lymphatic embolus and lack of radiocontrast flow past the embolus was documented at 12 weeks following surgery. CLINICAL SIGNIFICANCE: LE has the potential to reduce surgical failure by reducing efferent lymphatic chyle flow, occluding missed lymphatic branches and preventing the development of collateral branches.

What Is Your Diagnosis?

In collaboration with the American College of Veterinary Radiology.

Interpretation of cardiac chamber size on canine thoracic radiographs is limited and may result in the false identification of right-sided cardiomegaly in the presence of severe left-sided cardiomegaly.

Qualitative assessment of individual cardiac chamber enlargement on thoracic radiographs was assessed using echocardiography as the gold standard in dogs. Using this method, the presence of severe left-sided cardiomegaly was hypothesized to contribute to the false identification of right-sided cardiomegaly on radiographs. 175 dogs with three-view thoracic radiographs were retrospectively included in this diagnostic accuracy study if echocardiography was done within 24 h, and no rescue therapy was provided in the interim. All radiographic studies were reviewed by two groups of five board-certified veterinary radiologists with greater and less than 10 years of experience for grading of cardiac chamber enlargement as normal or mildly, moderately, or severely enlarged. The agreement, sensitivity, and specificity of the radiologists' interpretation of cardiac chamber size on thoracic radiographs to measured echocardiographic grades were evaluated. A total of 147 cases had complete echocardiographic data available for analysis. Intragroup agreement was moderate for the evaluation of left atrial enlargement and slight to fair for all other cardiac chambers. Between the mode of the radiologists' responses in the two groups and the echocardiographic grades, there was slight agreement for all cardiac chambers with higher severity grades reported using echocardiography. When moderate to severe left-sided cardiomegaly was identified on echocardiography, the sensitivity, specificity, and accuracy of radiographs were low, identifying dogs with radiographic evidence of right-sided cardiomegaly in the absence of corresponding right-sided cardiomegaly on echocardiography. Therefore, thoracic radiographs should be used with caution for the evaluation of cardiac chamber enlargement, particularly in the presence of severe left-sided cardiomegaly.

Comparison of the clinical, ultrasound, and CT findings in 13 dogs with gastric neoplasia.

Diagnosis of gastric tumors in dogs is difficult and is often obtained by biopsy following identification of a mass through ultrasound (US) or endoscopy. In human medicine, modalities such as CT and endoscopy are standard of care in the diagnosis and staging of gastric tumors. Although one veterinary study has described CT findings of gastric tumors in dogs using iatrogenic gas dilation, there are no veterinary studies that have directly compared the usefulness of US versus CT in the diagnosis and staging of these tumors. This retrospective, descriptive study evaluated US and CT images from 13 dogs. Gastric tumor diagnoses included leiomyoma (n = 4), adenocarcinoma (n = 3), leiomyosarcoma (n = 3), gastrointestinal stromal tumor (n = 2), and lymphoma (n = 1). Computed tomography was successful in identification of 92% of gastric tumors, while US identified only 69%. Computed tomography identified more locations of lymphadenopathy and correctly identified the location of gastric tumors more frequently than US when compared to the surgical, endoscopic, or necropsy reports. Most features seen on US and CT overlapped between the different tumor types. Lymphoma had a lower mean attenuation in CT than the other gastric tumors and was the only gastric tumor to not have complete loss of the gastric wall layering on US. As expected, adenocarcinoma appeared as gastric wall thickening with regional lymphadenopathy. Findings supported using CT as an ancillary diagnostic test for characterizing and staging gastric tumors in dogs and assisting in the selection of surgical candidates.