Chee Kin Lim

Tetralogy of Fallot and atrial septal defect in a white Bengal Tiger cub (Panthera tigris tigris).

A 3-week-old female white Bengal Tiger cub (Panthera tigris tigris) presented with acute onset tachypnoea, cyanosis and hypothermia. The cub was severely hypoxaemic with a mixed acid–base disturbance. Echocardiography revealed severe pulmonic stenosis, right ventricular hypertrophy, high membranous ventricular septal defect and an overriding aorta. Additionally, an atrial septal defect was found on necropsy, resulting in the final diagnosis of Tetralogy of Fallot with an atrial septal defect (a subclass of Pentalogy of Fallot). This report is the first to encompass arterial blood gas analysis, thoracic radiographs, echocardiography and necropsy findings in a white Bengal Tiger cub diagnosed with Tetralogy of Fallot with an atrial septal defect.

Survey of the prevalence and methodology of quality assurance for B‐mode ultrasound image quality among veterinary sonographers

Image quality in B-mode ultrasound is important as it reflects the diagnostic accuracy and diagnostic information provided during clinical scanning. Quality assurance programs for B-mode ultrasound systems/components are comprised of initial quality acceptance testing and subsequent regularly scheduled quality control testing. The importance of quality assurance programs for B-mode ultrasound image quality using ultrasound phantoms is well documented in the human medical and medical physics literature. The purpose of this prospective, cross-sectional, survey study was to determine the prevalence and methodology of quality acceptance testing and quality control testing of image quality for ultrasound system/components among veterinary sonographers. An online electronic survey was sent to 1497 members of veterinary imaging organizations: the American College of Veterinary Radiology, the Veterinary Ultrasound Society, and the European Association of Veterinary Diagnostic Imaging, and a total of 167 responses were received. The results showed that the percentages of veterinary sonographers performing quality acceptance testing and quality control testing are 42% (64/151; 95% confidence interval 34-52%) and 26% (40/156: 95% confidence interval 19-33%) respectively. Of the respondents who claimed to have quality acceptance testing or quality control testing of image quality in place for their ultrasound system/components, 0% have performed quality acceptance testing or quality control testing correctly (quality acceptance testing 95% confidence interval: 0-6%, quality control testing 95% confidence interval: 0-11%). Further education and guidelines are recommended for veterinary sonographers in the area of quality acceptance testing and quality control testing for B-mode ultrasound equipment/components.

Disseminated Rhodococcus equi in an Anglo‐Nubian goat

Disseminated Rhodococcus equi infection was diagnosed in an Anglo-Nubian goat presenting for non-weight bearing lameness of the right pelvic limb. Radiographs showed a moth-eaten osteolytic lesion in the proximal tibia suggestive of an aggressive bone lesion. Two pulmonary nodules were also present on thoracic radiographs. Initial antemortem cytology of the tibial lesion was suggestive of Rhodococcosis and the goat was sent to necropsy. Necropsy and bacterial culture confirmed the diagnosis of disseminated R. equi infection in the right tibia, lungs, and liver.

Ultrasonographic features of colonic B-cell lymphoma with mesenteric lymphomatosis in a cat

A 10-year-old male neutered Domestic Shorthair cat was referred for chronic inappetence, weight loss, and hematochezia and an abdominal mass. Abdominal ultrasonography revealed a heterogeneously hypoechoic transmural colonic mass, which extended beyond the serosa and into the adjacent mesentery. Cytology and clonality assays of fine needle aspirates of the mass and mesenteric nodules yielded a diagnosis of B-cell lymphoma. Colonic lymphoma with mesenteric involvement can have a similar appearance to carcinomatosis, therefore a definitive diagnosis requires sampling and further testing of the mesenteric lesions.

Radiographic and computed tomographic appearance of tracheal collapse with axial rotation in four dogs

Tracheal collapse with axial rotation was diagnosed in four dogs. Radiographs showed increased tracheal dorsoventral height at the caudal cervical and thoracic inlet with and apparent intraluminal soft tissue opacity, mimicking an intraluminal tracheal foreign body. Computed tomography confirmed dorsoventral tracheal collapse with axial rotation in all dogs. Short-term outcome with medical treatment of all dogs was excellent.

Optimized computed tomography protocol for assessment of dentition in alpacas

OBJECTIVE To determine the optimal protocol for acquisition of CT images of the dentition in alpacas. ANIMALS 3 healthy adult male alpacas. PROCEDURES Each alpaca was anesthetized with an IM injection of a combination of ketamine, xylazine, and butorphanol and positioned in sternal recumbency on the CT couch with its legs folded in a natural cush position and its head positioned within the isocenter of the gantry of a 64-slice CT scanner. Images were acquired by means of 6 protocols (sequential and helical modes at slice thicknesses of 1.25, 2.5, and 5 mm). Five images (2 molar, 2 premolar, and mandibular incisor teeth) were selected from each protocol for evaluation by 3 veterinary radiologists. For each image, tooth root visibility and sharpness and image noise artifact were subjectively evaluated on a 3-point scoring system. RESULTS Slice thickness significantly affected tooth root visibility and tooth root sharpness but did not affect image noise artifact. Acquisition mode significantly affected tooth root visibility and tooth root sharpness as well as image noise artifact. Tooth root visibility and sharpness did not differ significantly between the helical and sequential images when the slice thickness was 1.25 mm. Image noise artifact was greater for helical images than sequential images but did not differ by slice thickness within either acquisition mode. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that for a 64-slice CT scanner, the optimal protocol for the acquisition of CT images of the dentition in alpacas was a sequential scan with a slice thickness of 1.25 mm.

Clinical and histopathologic findings in dogs with the ultrasonographic appearance of gastric muscularis unorganized hyperechoic striations

BackgroundUltrasonographic appearance of unorganized hyperechoic striations (UHS) has been observed in the canine gastric muscularis layer. The purpose of the study was to determine the prevalence, sonographic and postmortem histologic features, and to determine the clinical significance of canine gastric muscularis UHS. In the prospective study, 72 dogs were included. The presence of gastric muscularis UHS were reviewed to determine its distribution and location. In the retrospective study, 167 dogs that had both abdominal ultrasonography and necropsy were included.ResultsThe prevalence of gastric muscularis UHS in dogs was 37.5% in the prospective and 5.4% in the retrospective studies respectively. The higher prevalence in prospective study was due to greater anticipation by the radiologists in search for gastric muscularis UHS. In the ventral gastric wall, the muscularis UHS were better defined when the gastric lumen was empty or non-distended, and were mostly parallel with the serosa when the gastric wall was distended (with gas or fluid). Visualization of the dorsal gastric wall was often obscured by gas shadowing from luminal gas. Histopathology was performed on eight dogs with gastric muscularis UHS, three of which had fibrous tissue observed with Masson’s trichrome stain.ConclusionPresence of gastric muscularis UHS in dogs may have been attributable to presence of incomplete interfaces between the inner oblique, middle circular and outer longitudinal layers of the gastric tunica muscularis or due to presence of fibrous tissue within the gastric muscularis layer. The clinical significance of canine gastric muscularis UHS is uncertain.