Variations in the morphology of lagomorph confluence sinuum on contrast enhanced CT.

Knowledge of lagomorph confluence sinuum anatomy on contrast-enhanced CT may prevent the misdiagnoses of intracranial, extra-axial masses. The purpose of this retrospective, observational, descriptive study was to describe the characteristics of the confluence sinuum in rabbits on contrast-enhanced CT. Images of 24 rabbits who had pre- and postcontrast CT sequences of the skull were reviewed by an American College of Veterinary Radiology-certified veterinary radiologist and third-year radiology resident. Degree of contrast enhancement within the region of the confluence sinuum was graded based on consensus as no (0), mild (1), moderate (2), or marked (3) contrast enhancement. Hounsfield units (HU) of the confluence sinuum was measured in three different regions of interest, averaged for each patient, and divided into each group for comparison using one-way ANOVA analysis. Contrast enhancement was mild in 45.8% (11/24) rabbits, moderate in 33.3% (8/24), marked in 20.8% (5/24), and none in 0.0% (0/24). There were significant differences (P < 0.05) between the average HU of the mild and marked group (P-value = 0.0001) and moderate and marked groups (P-value = 0.0010). Two rabbits with marked contrast enhancement were initially misdiagnosed with an intracranial, extra-axial mass along the parietal lobe based on contrast-enhanced CT. On necropsy, no gross or histopathological abnormalities were identified in the brain for these rabbits. In summary, contrast enhancement was identified in all rabbits (24/24) on contrast-enhanced CT imaging . This normal structure can be variable in size should not be mistaken for a pathological lesion in the absence of mass effect, secondary calvarial lysis, or hyperostosis.

Rapport de cas Ossifying fibroma in the cervical vertebra of a dog.

The objective of this study was to describe the clinical signs, neurologic examination findings, diagnostic imaging results, and pathologic diagnosis of ossifying fibroma in the cervical vertebra of a dog. A 3-year-old spayed female Pembroke Welsh corgi dog exhibited severe cervical pain and left-sided postural reaction deficits. Magnetic resonance imaging (MRI) revealed a lobulated contrast enhancing mass associated with the C6 cervical vertebra. Due to the lack of response to pain medications, humane euthanasia was elected, and histopathologic evaluation of the mass revealed a fibro-osseous lesion most consistent with an ossifying fibroma. This neoplasm is most commonly associated with the mandible of young horses and has not been previously reported in vertebrae in veterinary medicine. Key clinical message: This case is the first report of a fibro-osseous lesion most consistent with an ossifying fibroma affecting a vertebra in veterinary medicine.

Fibrome ossifiant dans la vertèbre cervicale d'un chien. Décrire les signes cliniques, les résultats de l'examen neurologique, les résultats de l'imagerie diagnostique et le diagnostic pathologique du fibrome ossifiant dans la vertèbre cervicale d'un chien. Une chienne Pembroke Welsh corgi femelle stérilisée âgée de 3 ans présentait de fortes douleurs cervicales et des déficits de réaction posturale du côté gauche. L'imagerie par résonance magnétique (IRM) a révélé une masse lobulée augmentant le contraste associée à la vertèbre cervicale C6. En raison de l'absence de réponse aux analgésiques, l'euthanasie a été choisie et l'évaluation histopathologique de la masse a révélé une lésion fibro-osseuse plus compatible avec un fibrome ossifiant. Ce néoplasme est le plus souvent associé à la mandibule des jeunes chevaux et n'a jamais été signalé auparavant dans les vertèbres en médecine vétérinaire.Message clinique clé :Ce cas est le premier rapport d'une lésion fibro-osseuse plus compatible avec un fibrome ossifiant touchant une vertèbre en médecine vétérinaire.(Traduit par Dr Serge Messier).

Computed tomography of testicular torsion in a juvenile dog with unilateral cryptorchidism.

A 14-week-old male unilaterally cryptorchid Clumber spaniel was presented for acute lethargy. Physical examination revealed abdominal pain, and a single testis was palpated in the scrotum. Abdominal ultrasound and computed tomography (CT) revealed a poorly vascularized, ovoid structure immediately caudal to the left kidney with scant regional peritoneal effusion. Left intra-abdominal testicular torsion was confirmed at surgery, and routine cryptorchidectomy was performed. The patient recovered uneventfully from anesthesia and surgery. Key clinical message: The most common CT characteristics of testicular torsion were present in this case and correlated well with sonographic findings to allow for rapid, accurate diagnosis and surgical planning of unilateral, non-neoplastic, intra-abdominal cryptorchid testicular torsion in a juvenile dog. Contrast enhanced CT facilitated accurate localization of the undescended testis and evaluation of testicular perfusion and may be a useful alternative to ultrasound for diagnosing testicular torsion, especially in indeterminate cases.

Tomodensitométrie d'une torsion testiculaire chez un chien juvénile atteint de cryptorchidie unilatérale. Un épagneul Clumber avec une cryptorchidie unilatérale âgé de 14 semaines a été présenté pour une léthargie aiguë. L'examen physique a révélé des douleurs abdominales et un seul testicule a été palpé dans le scrotum. L'échographie abdominale et la tomodensitométrie ont révélé une structure ovoïde mal vascularisée immédiatement caudale au rein gauche avec peu d'épanchement péritonéal régional. Une torsion testiculaire intra-abdominale gauche a été confirmée lors de la chirurgie et une cryptorchidectomie de routine a été réalisée. Le patient s'est remis sans incident de l'anesthésie et de la chirurgie.Message clinique clé:Les caractéristiques tomodensitométriques les plus courantes de la torsion testiculaire étaient présentes dans ce cas et bien corrélées avec les résultats échographiques pour permettre un diagnostic rapide et précis et une planification chirurgicale de la torsion testiculaire avec cryptorchidie unilatérale, non néoplasique et intra-abdominale chez un chien juvénile. La tomodensitométrie avec contraste a facilité la localisation précise du testicule non descendu et l'évaluation de la perfusion testiculaire et peut être une alternative utile à l'échographie pour diagnostiquer la torsion testiculaire, en particulier dans les cas indéterminés.(Traduit par Dr Serge Messier).

Resolution of tracheal collapse and stenosis without surgical intervention in two Holstein calves.

CASE DESCRIPTION: A 4-month-old 127.5-kg (280.5-lb) Holstein heifer calf (patient 1) and a 4-month-old 174-kg (382.8-lb) Holstein bull calf (patient 2) of high genetic value were examined because of signs of respiratory tract disease (dyspnea, wheezing, and coughing) of 2 and 3 months' duration, respectively, that did not respond to antimicrobial and anti-inflammatory treatment. Patient 1 was born with assistance owing to malpresentation and dystocia. The birth of patient 2 was unobserved. CLINICAL FINDINGS: For both calves, results of a physical examination, CBC, serum biochemical analysis, thoracic radiography and CT, and nasotracheal endoscopy led to the diagnosis of tracheal collapse and stenosis secondary to perinatal rib fractures. Neither calf had evidence of substantial lower airway disease. TREATMENT AND OUTCOME: Both calves were discharged from the hospital with the recommendation that they be individually housed in cool, well-ventilated stalls with no access to headlocks. The clinical signs abated, and surgical intervention was not pursued in either patient. Both patients grew as expected and achieved reproductive maturity, with patient 1 becoming an oocyte donor and patient 2 being purchased by a commercial bull stud company. Patient 1 was reevaluated at 21 months old, and patient 2 was reevaluated at 26 months old. Results of follow-up thoracic radiographic (patient 1) and nasotracheal endoscopic (both patients) examinations indicated an anatomically normal trachea with no evidence of collapse or stenosis. CLINICAL RELEVANCE: This report was the first to describe successful resolution of tracheal collapse and stenosis secondary to perinatal rib fracture in dairy calves without surgical intervention.