Diagnostic utility of ultrasound-guided fine-needle aspiration and needle-core biopsy sampling of canine splenic masses.

This prospective clinical study sought to determine the accuracy of cytopathologic examination and needle-core biopsy (NCB) against diagnoses obtained by excisional histopathology (EH) for canine splenic masses. Twenty-five masses were evaluated ex vivo by ultrasound-guided fine-needle aspiration (FNA) and NCB tissue sampling. Each spleen was placed in a container and artificial skin placed over its surface. Ultrasound-guided FNA using a 22-gauge needle and 2 NCB samples [14-gauge (NCB-14), 16-gauge (NCB-16)] were obtained and submitted for analysis. Results were compared to results obtained by splenic excisional histopathology (EH). There was no difference noted between FNA, NCB-14, or NCB-16 analyses. In addition, there was no difference in accuracy between FNA and NCB-14 or between FNA and NCB-14 versus NCB-16. Reported accuracy of FNA was 0.72, NCB-14 was 0.72, and NCB-16 was 0.64, respectively. Both FNA and NCB-14 displayed a sensitivity of 71% and NCB-16 a sensitivity of 53%. Both FNA and NCB-14 displayed a specificity of 75% and NCB-16 a specificity of 88%. The results demonstrated that NCB had no advantage clinically over FNA at diagnosing splenic pathology. This study further demonstrates that preoperative diagnostic evaluation of the spleen is not highly accurate and cannot be recommended prior to splenectomy.

Cette étude clinique prospective visait à déterminer la précision de l'examen cytopathologique et de la biopsie au trocart (NCB) par rapport aux diagnostics obtenus par histopathologie excisionnelle (EH) pour les masses spléniques canines. Vingt-cinq masses ont été évaluées ex vivo par aspiration à l'aiguille fine guidée par ultrasons (FNA) et prélèvement de tissu par NCB. Chaque rate a été placée dans un récipient et une peau artificielle placée sur sa surface. Une FNA guidée par ultrasons à l'aide d'une aiguille de calibre 22 et de 2 échantillons de NCB (calibre 14 (NCB-14), calibre 16 (NCB-16)) ont été obtenues et soumises pour analyse. Les résultats ont été comparés aux résultats obtenus par histopathologie excisionnelle splénique (EH). Aucune différence n'a été notée entre les analyses FNA, NCB-14 ou NCB-16. De plus, il n'y avait aucune différence de précision entre FNA et NCB-14 ou entre FNA et NCB-14 par rapport à NCB-16. La précision rapportée de FNA était de 0,72, celle de NCB-14 de 0,72 et de NCB-16 était de 0,64, respectivement. FNA et NCB-14 ont affiché une sensibilité de 71 % et NCB-16 une sensibilité de 53 %. FNA et NCB-14 ont affiché une spécificité de 75 % et NCB-16 une spécificité de 88 %. Les résultats ont démontré que la NCB n'avait aucun avantage clinique sur la FNA pour diagnostiquer la pathologie splénique. Cette étude démontre en outre que l'évaluation diagnostique préopératoire de la rate n'est pas très précise et ne peut être recommandée avant la splénectomie.(Traduit par Docteur Serge Messier).

Flexed radiographic angles for determination of atlantoaxial instability in dogs.

OBJECTIVE: To determine a flexed position for radiographic diagnosis of atlantoaxial instability (AAI) and to identify radiographic measurement cutoffs to differentiate affected dogs from neurologically healthy toy breeds. STUDY DESIGN: Retrospective case series and prospective case controls. ANIMALS: Thirty-nine client-owned toy breed dogs in which AAI had been diagnosed and 20 neurologically healthy client-owned toy breed dogs. METHODS: Medical records from three institutions were retrospectively reviewed to identify dogs affected with AAI. Flexed lateral images were reviewed, and measurements were obtained by using anatomic landmarks. Radiography was performed with control dogs to obtain the same measurements. RESULTS: Flexed lateral radiographs of thirty dogs affected with AAI were found to be positioned at a mean of 51° flexion. When flexed lateral radiographs were evaluated with a cutoff value for atlas to axis angle (AAA) >10°, evaluation of all breeds represented revealed a 90% sensitivity and 90% specificity. When this cutoff was evaluated in Yorkshire terriers, Chihuahuas, and mixes of these breeds, the sensitivity was 92%, and the specificity was 92%. When the control sample was positioned at 51° ± 10°, only two of the dogs were within the AAA cutoff value of >10°. There was no difference between the measurements obtained by using the flexed lateral view (mean = 50.9°) and the exaggerated flexed lateral view (mean = 38.9°) in the control sample. CONCLUSION: This study established objective measurements for the positioning and diagnosis of AAI on flexed lateral radiographs in toy breed dogs. CLINICAL SIGNIFICANCE: Atlantoaxial instability can be objectively diagnosed in sedated or anesthetized toy breed dogs when applying 51° flexion to cervical radiographs.

Mucoepidermoid Carcinoma in the Skull of an Orange-winged Amazon Parrot (Amazona amazonica).

A 33-year-old female intact orange-winged Amazon parrot (Amazona amazonica) presented for a slowly growing mass over the right eye. A computed tomography scan performed with and without intravenous contrast revealed a heterogeneous mixed soft tissue and mineral-dense mass with a small area of non-contrast-enhancing fluid density located between the orbits at the caudal aspect of the nasal passages, with associated lysis of the right caudal nasal passage and the right frontal bone. Following euthanasia, the mass was found to consist of soft tissue between the right eye and nostril over the right frontal bone. Lysis of the underlying bone resulted in a bony defect leading into the infraorbital sinus along the dorsorostral aspect of the right eye. Histopathology revealed an unencapsulated, poorly demarcated, highly cellular neoplasm composed of islands and trabeculae of neoplastic cells embedded in abundant loose fibrovascular stroma which completely obliterated the cortical bone and sinuses of the rostral skull and infiltrated the surrounding muscle and soft tissue. Histologically, the tumor was consistent with a high-grade mucoepidermoid carcinoma, characterized by the presence of epidermoid, intermediate, and mucous-producing cell types. No evidence of metastasis was identified. The tissue of origin was suspected to be salivary or nasal mucous glands, but was difficult to confirm due to distortion of normal tissue architecture as a result of the tumor. Although mucoepidermoid carcinomas are a common salivary gland tumor in human medicine, they are not well recognized in avian species, and no specific case reports exist describing this pathology in an Amazon parrot. Despite the lack of distinct salivary glands in most avian species, mucoepidermoid carcinomas can occur, can cause significant clinical disease, and should be included as a differential diagnosis for avian patients presenting with similar lesions.

MULTICENTRIC T-CELL LYMPHOMA AND CUTANEOUS HEMANGIOSARCOMA IN A CAPTIVE CHEETAH (ACINONYX JUBATUS).

A 13-yr-old intact male cheetah (Acinonyx jubatus) presented for evaluation after a 4-mo history of intermittent lethargy and increased expiratory effort. The clinical signs were initially noted after the diagnosis and death of its 13-yr-old male sibling with solitary hepatic T-cell lymphoma. Physical examination findings included thin body condition, harsh lung sounds, peripheral lymphadenopathy, and a cutaneous mass on the right medial tarsus and scrotum. Excisional biopsies diagnosed well-differentiated cutaneous hemangiosarcomas. Thoracic radiographs revealed a cranial mediastinal mass. Complete blood count and serum biochemical analyses showed a leukocytosis with persistent lymphocytosis, progressive azotemia, and markedly elevated alkaline phosphatase. Because of the cheetah's declining quality of life, euthanasia was elected. Postmortem examination, histopathology, and immunohistochemical staining revealed multicentric T-cell lymphoma. Feline leukemia virus (FeLV) enzyme-linked immunosorbent assay, FeLV polymerase chain reaction (whole blood), and viral metagenomic analysis were negative. This is the first case of cutaneous hemangiosarcoma and multicentric T-cell lymphoma reported in a FeLV-negative cheetah.

SOLITARY T-CELL HEPATIC LYMPHOMA WITH LARGE GRANULAR LYMPHOCYTE MORPHOLOGY IN A CAPTIVE CHEETAH (ACINONYX JUBATUS).

A 13-yr-old male cheetah (Acinonyx jubatus) presented for an acute history of lateral recumbency and anorexia. Upon physical examination under general anesthesia, severe icterus was noted. A serum biochemical profile confirmed markedly elevated total bilirubin and alanine transaminase. Based on ultrasound-guided liver aspirates and cytology, a presumptive diagnosis of large granular lymphocyte hepatic lymphoma was reached. Abdominal and thoracic radiographs did not assist in reaching an antemortem diagnosis. Postmortem examination and histopathology provided a definitive diagnosis of hepatic lymphoma with acute massive hepatocelluar necrosis and hemorrhage, as well as concurrent lesions of gastric ulcers, ulcerative and sclerosing enteritis, myocardial hypertrophy, and splenic myelolipomas. Immunohistochemistry of the liver yielded CD-3 positive and CD-20 negative results, confirming lymphocytes of a T-cell lineage. Due to concern for possible retrovirus-associated disease, enzyme-linked immunosorbent assays for feline leukemia virus and feline immunodeficiency virus were performed retrospectively on a banked serum sample and yielded negative results, thus diminishing concern for the male conspecific housed in the same exhibit.