Use of color flow Doppler ultrasonography to diagnose a bleeding neuroendocrine tumor in the gallbladder of a dog.

CASE DESCRIPTION: A 13-year-old neutered female Keeshond-cross was evaluated because of a history of melena, anemia, hematemesis, vomiting, and high serum liver enzyme activities over a 1.5-year period. CLINICAL FINDINGS: Abdominal ultrasonography revealed a hyperechoic mass in the gallbladder. In the gallbladder mass itself, a distinct linear blood flow pattern was detected by use of color flow Doppler ultrasonography. TREATMENT AND OUTCOME: A cholecystectomy was performed, and clinical signs resolved. Samples of the mass were examined histologically and immunohistochemically, and findings supported a diagnosis of neuroendocrine tumor of the gallbladder. CLINICAL RELEVANCE: Tumors of the biliary tree are a potential source of blood loss into the gastrointestinal tract. Color flow Doppler ultrasonography in conjunction with conventional grayscale ultrasonography may be useful in evaluation of the gallbladder in dogs. When echogenic material is detected in the gallbladder, it is important to evaluate the region for blood flow.

Comparison of aspiration and nonaspiration techniques for obtaining cytologic samples from the canine and feline spleen.

BACKGROUND: Ultrasound-guided fine needle aspiration of the spleen is commonly used in the diagnostic evaluation of veterinary patients. Techniques using suction delivered through a 6-20-cm(3) syringe are the most commonly described means of obtaining cytologic samples of the spleen. Comparison studies of various human lesions have shown nonaspiration techniques to produce equal or superior cytologic specimens with less blood than specimens obtained using aspiration techniques. OBJECTIVE: The purpose of this study was to compare the quality of splenic cytology specimens obtained using aspiration and nonaspiration techniques. METHODS: Client-owned dogs (n=24) and cats (n=7) receiving an abdominal ultrasound at the University of Tennessee College of Veterinary Medicine were enrolled in the study between January and June 2005. Samples were obtained from patients with and without sonographic splenic abnormalities. Two clinical pathologists, working independently and blinded to the method of sample collection, graded the cytologic specimens using a subjective scoring system for cellularity, amount of blood, and preservation of cellular morphology. RESULTS: Agreement between the 2 independent observers was good. Direct comparison of the 2 techniques showed that samples obtained by the nonaspiration method had higher cellularity (P=.0002), less blood (P=.0023), and similar cell morphology (P=1.0000) compared with samples obtained by the aspiration method. CONCLUSION: These results suggest the nonaspiration technique is a superior method for obtaining a high-quality cytologic specimen from the canine and feline spleen.

Bone and lean tissue changes following cranial cruciate ligament transection and stifle stabilization.

Following cranial cruciate ligament transection and extracapsular stabilization, dual-energy X-ray absorptiometry was used to analyze bone mineral content and lean tissue mass in the surgical and nonsurgical legs (n=14) at 0, 2, 4, and 8 weeks, and to evaluate bone mineral content and bone mineral density (BMD) of the proximal, mid-, and distal tibia of both the surgical and nonsurgical legs (n=15) at 0, 5, and 10 weeks. There was significant loss of bone mineral content and lean tissue in the surgical leg compared to the nonsurgical leg. Significant loss in bone mineral content and BMD was detected in the tibia of the surgical leg and was most pronounced in the metaphyseal region.

Correlation between hepatobiliary scintigraphy and surgery or postmortem examination findings in dogs and cats with extrahepatic biliary obstruction, partial obstruction, or patency of the biliary system: 18 cases (1995-2004).

OBJECTIVE: To evaluate the usefulness of serum biochemical variables and scintigraphic study results for differentiating between dogs and cats with complete extrahepatic biliary obstruction (EHO) and those with partial EHO or patent bile ducts. STUDY DESIGN: Retrospective case series. ANIMALS: 17 dogs and 1 cat. PROCEDURE: Animals that underwent hepatobiliary scintigraphy and had either surgical or postmortem confirmation of the degree of bile duct patency were included. Scintigraphic images were evaluated and biliary tracts were classified as patent, partially obstructed but patent, or obstructed. Surgery or postmortem examination was considered the gold standard for diagnosis, and compared with those findings, sensitivity and specificity of scintigraphy were calculated. RESULTS: With absence of radioactivity in the intestinal tract as the diagnostic criterion for EHO, the sensitivity and specificity of scintigraphic diagnosis were both 83% when final images were acquired at 19 to 24 hours, compared with 100% and 33%, respectively, when 180 minutes was used as the cutoff time. Animals with partial biliary obstruction had less intestinal radioactivity that arrived later than that observed in animals with patent biliary tracts. CONCLUSIONS AND CLINICAL RELEVANCE: Animals in which intestinal radioactivity has not been observed after the standard 3 to 4 hours should undergo additional scintigraphic imaging. Findings in animals with partial biliary obstruction include delayed arrival of radioactivity and less radioactivity in the intestine. Distinguishing between complete and partial biliary tract obstruction is important because animals with partial obstruction may respond favorably to medical management and should not be given an erroneous diagnosis of complete obstruction.

Use of computed tomography and radiolabeled leukocytes in a cat with pancreatitis.

The normal feline pancreas has been evaluated using radiolabeled leukocytes (99mTc-HMPAO) and computed tomography. The purpose of this report is to describe a clinical case where both modalities were utilized to assess the inflamed feline pancreas. A nine year old female cat presented with anorexia, depression and some vomiting. Blood values were unremarkable. Radiographs and ultrasound were suggestive of pancreatitis. The cat's leukocytes were separated and labeled according to an established protocol. Whole body images were acquired immediately, at 5 and 30 min, and at 1, 2, 4, and 17 hours post injection. Approximately 48 h later, the animal was anesthetized and computed tomography of the abdomen was preformed both pre and post contrast. Surgical biopsies were taken. The distribution of the WBCs was similar to that documented in normal animals, however, at 2 h there was faint uptake seen in the region of the pancreas. This uptake became more intense at 4 h and persisted at 17 h. Computed tomography showed irregular margination of the pancreas, it was larger than normal and inhomogeneous. Contrast enhancement was inhomogeneous and its peak enhancement was not reached until 10 min post injection; normal feline pancreas enhances homogeneously and peaks immediately. Histopathology confirmed pancreatitis with lymphocytic, plasmacytic, neutrophilic and eosinophilic inflammation and fibrosis. Radiolabeled leukocytes can be used to document pancreatic inflammation and this is best seen 4 h after injection. Computed tomography allows superior visualization of the pancreas. Both the appearance and contrast enhancement pattern of the inflamed pancreas differ from normal.

Evaluation of the feline pancreas using computed tomography and radiolabeled leukocytes.

This study was designed to test the feasibility and utility of computed tomography and radiolabeled granulocytes in evaluating the feline pancreas in six normal cats. Autologous granulocytes were labeled with 99mTc-hexamethylpropyleneamine oxime (HMPAO) and injected into each cat. Whole body scintigraphic images were acquired at 1, 5, 15, and 30 minutes, and 1, 2, and 4 hours following injection. The following day, each cat was anesthetized and computed tomographic images of the abdomen were acquired both pre- and post-contrast. Following CT, a surgical pancreatic biopsy was collected. Feline granulocytes were successfully labeled with 99mTc-HMPAO with a labeling efficiency of 15-42% (average of 27%). An average of 5.42 x 10(7) cells in a 2 mL volume were injected into each cat. Less than 1 minute was required to acquire 500,000 count images. Granulocytes distributed predominantly to the lung, spleen and liver in order of decreasing activity. Only background activity was identified in the region of the pancreas. The pancreas was easily identified on CT images of the abdomen. The pancreas was hypoattenuating relative to both the spleen and liver. The pancreas enhanced with the administration of contrast medium, peaking immediately, then gradually clearing over the 30-minute test period. Following contrast medium administration the pancreas remained hypoattenuating relative to the spleen. All biopsies confirmed the absence of pancreatic inflammation in the study cats and no adverse effects were recognized as a result of pancreatic biopsy. Both computed tomography and radiolabeled granulocytes appear to hold promise as imaging procedures for the detection of feline pancreatitis. We predict that these described normal parameters may be altered in the face of inflammation, facilitating detection of feline pancreatitis. Data from cases of suspect feline pancreatitis are needed to evaluate these methods for clinical utility.

Mineralized paraprostatic cyst as a potential contributing factor in the development of perineal hernias in a dog.

Perineal hernias almost exclusively affect male dogs (sexually intact or castrated). Factors that may contribute or predispose a dog to perineal hernias include tenesmus, pelvic musculature variations (male vs female), and gonadal hormone influence. In dogs with perineal hernias and tenesmus it is important to include rectal and prostatic diseases, including paraprostatic cysts, in the differential list of potential underlying causes. Surgical correction of the perineal hernia with a perineal herniorrhaphy is indicated. Successful treatment depends on the degree of preexisting neurologic alterations, meticulous surgical technique, and identification and correction of underlying contributing factors. Paraprostatic cysts develop predominantly in sexually intact medium to large breed dogs. These cysts are thin-walled structures often attached to the prostatic dorsal midline. Osseous metaplasia of paraprostatic cysts may occur. Clinical signs of tenesmus often result from compression on adjacent structures (urinary bladder and colon), and tenesmus may contribute to the development of perineal hernias. Preferred treatment of a paraprostatic cyst is surgical removal and castration. This report describes a dog with bilateral perineal hernias and a large mineralized paraprostatic cyst that was identified as a possible contributing factor to the hernias.