CT features of gastrointestinal spindle cell, epithelial, and round cell tumors in 41 dogs.

There is sparse published information on computed tomographic (CT) characteristics of canine gastrointestinal tumors. The purposes of this multi-center, retrospective, descriptive study were to describe the CT features of histologically-confirmed canine gastrointestinal spindle cell, epithelial, and round cell tumors and, when available, describe the corresponding ultrasound findings. The inclusion criteria were as follows: availability of pre-and post-contrast CT study, and a histopathological diagnosis of the lesions. Recorded parameters were tumor size, location, gastrointestinal wall layers involvement, lesion's growth and enhancement patterns, tumor margination, presence of stenosis, mineralization, ulcerations, lymphadenopathy, or other lesions in the abdomen/thorax. When available, ultrasound images were evaluated. Forty-one dogs met the inclusion criteria and had the following histological diagnoses: 21/41 (51%) spindle cells (7 leiomyomas, 14 leiomyosarcomas/gastrointestinal stromal tumors (GISTs)), 13/41 (32%) epithelial (adenocarcinoma), and 7/41 (17%) round cell (lymphoma) tumors. The growth pattern was concentric, eccentric, and mixed in epithelial, spindle cell, and round cell tumors, respectively. Spindle cell tumors had the largest main volume and involved the outer gastrointestinal layer with an unaffected inner layer. Leiomyosarcomas/GISTs showed irregular margins compared to leiomyomas. Only lymphomas showed multifocal gastrointestinal involvement. Nine carcinomas and six spindle cell tumors caused partial stenosis with secondary sub-obstruction. Mineralizations were more frequent in spindle cell tumors (10/21) and absent in lymphomas. Lymphadenomegaly was widespread in lymphomas, regional in leiomyosarcomas-GISTs and adenocarcinomas, and absent in leiomyomas. The reported CT features may be useful in prioritizing the differential diagnosis between spindle cell, epithelial, and round cell tumors, similar to those reported on ultrasound.

Portal vein thrombosis in cats: 6 cases (2001-2006).

BACKGROUND: Portal vein thrombosis (PVT) in cats is sparsely reported. PURPOSE OF STUDY: To evaluate the clinical signs and diseases associated with PVT in cats. ANIMALS: 6 client-owned cats. METHODS: Medical records for cats with a portal vein thrombus diagnosed on abdominal ultrasound or at necropsy were reviewed. Signalment, historical data, underlying disorders, clinical findings, clinicopathologic and histopathologic data, diagnostic imaging findings, treatment, and outcome were recorded. RESULTS: All 6 cats identified with PVT also had hepatic disease. Evidence of a congenital portosystemic shunt was present in 3/6 cats. Two cats had primary or metastatic hepatic neoplasia. One cat had acute cholangitis, acute pancreatitis, and locally extensive acute centrilobular hepatic necrosis. Two cats were suspected to have acute thrombi and 4 cats had chronic thrombi. CONCLUSION AND CLINICAL SIGNIFICANCE: PVT might be an important concurrent finding in cats with hepatic disease.

Ultrasonography of the normal feline pancreas and associated anatomic landmarks: a prospective study of 20 cats.

The sonographic appearance of the feline pancreas and associated anatomic landmarks including the pancreatic duct, duodenum, duodenal papilla, portal vein, and gastric lymph node were evaluated in 20 healthy, awake cats. The pancreas appeared nearly isoechoic to surrounding mesenteric tissues, isoechoic to slightly hyperechoic to adjacent liver lobes, and hypoechoic to the spleen. The mean thickness measurements for the right pancreatic lobe, body, and left pancreatic lobe were 4.5 mm (range 2.8-5.9), 6.6 mm (range 4.7-9.5), and 5.4 mm (range 3.4-9.0), respectively. The pancreatic duct was consistently visualized in the left pancreatic lobe and had a mean thickness of 0.8 mm (range 0.5-1.3). It could be differentiated from the pancreatic vessel, by its central location, and the duct's lack of Doppler flow signal. The duodenum was used as a landmark to identify the right lobe of the pancreas. The mean duodenal wall thickness measurement was 2.8 mm (range 2.1-3.8) in sagittal section, and 3.0 mm (range 2.2-4.4) in transverse section. The duodenal papilla was identified in 4 of 20 cats. It ranged in size from 2.9 to 5.5 mm in width, and had a maximum height of 4.0 mm in transverse section. The portal vein was used as a consistent anatomic landmark for identification of the left lobe and body of the pancreas. The mean diameter of the portal vein at the level where the pancreatic body joins the left pancreatic lobe was 4.3 mm (range 2.7-5.9) when viewed in sagittal section, and 4.5 mm (range 3.6-6.1) in transverse section. The gastric lymph node was identified cranial and ventromedial to the pyloroduodenal angle in 6 of 20 cats. It had an asymmetrical shape with a larger caudal pole in five of the six cats. The largest dimensions of the gastric lymph node were 10 mm in length, and 6 mm in width for the larger caudal pole, and 5.1 mm in width for the smaller cranial pole.

Correlation between coagulation profile findings and bleeding complications after ultrasound-guided biopsies: 434 cases (1993-1996).

Medical records of 434 consecutive dogs (n=310) and cats (n=124) that received coagulation studies prior to ultrasound-guided biopsy procedures between January 1993 and June 1996 were reviewed for bleeding complications. Minor complications occurred in 21.9% of cases. Major complications occurred in 6% of the cases. Significant bleeding complications were observed in thrombocytopenic cases (P=0.0001). Dogs with a prolonged one-stage prothrombin time (OSPT) (P=0.031) and cats with prolonged activated partial thromboplastin time (aPTT) (P=0.024) were more likely to have complications than patients with normal values. Adequate tissue for histopathological diagnosis was obtained in 96.3% of cases. The likelihood of complication was smaller when the liver was biopsied than when the kidney was biopsied (n=259; P=0.0327). Ultrasound-guided biopsy of intracavitary structures is an effective and relatively safe procedure, but delay of the procedure should be considered when thrombocytopenia is present in the patient.

Characterization of gastrointestinal tumors.

Transabdominal ultrasonography is used increasingly for the evaluation of gastrointestinal disorders in small animals, including neoplasms such as lymphosarcoma, carcinoma, and smooth muscle tumors (leiomyoma, leiomyosarcoma). An updated summary of the clinical studies currently investigating the use of ultrasonography to detect and to characterize gastrointestinal neoplasia is presented in this article.

Updates in interventional ultrasonography.

Interventional ultrasonography, including diagnostic, therapeutic, and intraoperative interventions, is a rapidly developing field in both human and veterinary medicine. Growing expertise and significant improvements in the technology have contributed to the innovation of numerous ultrasound-assisted procedures. Ultrasound-guided biopsy and fine-needle aspiration are now commonly performed. New techniques and the indications for other procedures such as cavity drainage, indwelling catheter placement, and intraoperative procedures are presented.

Ultrasonography of canine gastric epithelial neoplasia.

Signalment, clinical and ultrasonographic findings from 16 dogs with histologically confirmed gastric epithelial neoplasia were reviewed. The most common clinical findings were vomiting, anorexia and weight loss. Hematemesis and melena were uncommon findings. Ten (10/16) dogs were female and there were four Chows. The most common ultrasonographic findings were transmural thickening of the gastric wall associated with altered wall layering. A poorly echogenic lining often was noted on the innermost and/or the outermost portions of the gastric wall, separated by a more echogenic central zone. The distribution of these changes was variable. This ultrasonographic feature, called pseudolayering, was present in 14 dogs. It was believed to most likely correlate to the unevenly layered tumor distribution noted histopathologically. The maximum wall thickening ranged from 1 cm to 2.7 cm. Regional lymphadenopathy was identified ultrasonographically in 15 dogs. Ultrasound-guided fine-needle aspiration biopsy or automated microcore biopsy, endoscopic biopsy, surgical biopsy or necropsy resulted in the diagnosis of carcinoma in 15 dogs and of carcinoid tumor in one dog. The results of this study suggested that ultrasonography was a useful tool for the detection and diagnosis of canine gastric epithelial neoplasia. Furthermore, ultrasonography can assist in obtaining diagnostic samples and in clinical staging of the tumor.

Hepatic abscesses in 13 dogs: a review of the ultrasonographic findings, clinical data and therapeutic options.

Historical, physical examination, clinicopathologic, radiographic and ultrasonographic findings of 13 dogs with hepatic abscesses were reviewed. Liver abscessation was characterized by number, size, shape, echogenicity and location. Solitary lesions greater than 3 cm were more common than multiple ones. The abscesses were mainly poorly echogenic lesions, often with central cavitation. The shape of the lesion ranged from round to oval or irregular. Enhancement artifact, abdominal effusion, regional lymphadenopathy and hyperechoic perihepatic fat, were identified in several dogs. Ultrasound-guided aspiration was performed in 10 of 13 dogs, and confirmed abscessation with cytologic and microbiologic evaluation. Ultrasound-guided percutaneous drainage of abscesses was performed as an adjunct to medical management in four dogs.

Retrospective ultrasonographic evaluation of adrenal lesions in 26 dogs.

A review was performed of ultrasonographic findings in 26 dogs with confirmed adrenal lesions. Adrenal shape, size, echogenicity, laterality, and the presence of vascular invasion were evaluated. Histopathologic diagnoses were obtained in all dogs. Adrenal lesions were confirmed as pheochromocytomas (9), adenocarcinomas (6), a poorly differentiated blastoma (1), bilateral adrenal metastases of a carcinoma (1), adenomas--one of which was bilateral--(4) and hyperplasia (6). Size and shape were extremely variable and not specific to lesion type. There was a tendency for pheochromocytomas (7), adenocarcinomas (5) and poorly differentiated blastoma (1) to be rounded masses. Adenomas (4), hyperplasia (7) and adrenal metastases (2) presented predominantly as nodules. No specificity in echogenicity was noted. Mineralization and bilaterality were present in both benign and malignant lesions. Vascular extension or the presence of a thrombus were suggestive but not specific signs of malignancy. Based on our preliminary study, ultrasonography is an effective method for localizing adrenal lesions and is helpful in assessing their extension. However, no definitive differentiation between benign and malignant lesions was possible using ultrasonographic criteria alone.

Imaging of adrenal gland disorders.

In recent years, diagnostic imaging has become an important adjunct to conventional endocrine testing in the evaluation of adrenal gland dysfunction. This article discusses the role of imaging in the diagnostic workup of the following adrenal gland disorders: hypercatacholaminism, hyperaldosteronism, hyperadrenocorticism, and hypoadrenocorticism. The strengths and limitations of radiography, ultrasonography, scintigraphy, CT scanning, and MR imaging are addressed.

Alimentary lymphoma in cats: 28 cases (1988-1993).

OBJECTIVE: To evaluate response to chemotherapy in cats with alimentary lymphoma and to determine factors associated with survival time. DESIGN: Retrospective case series. ANIMALS: 28 cats with alimentary lymphoma that underwent chemotherapy. RESULTS: In all cats, the diagnosis had been established by means of cytologic or histologic examination of ultrasound-guided aspirates and biopsy specimens (18 cats), histologic examination of surgically obtained biopsy specimens (7 cats), or examination of specimens obtained endoscopically (3 cats). Clinical signs included anorexia, weight loss, vomiting, and diarrhea. Twenty-seven cats were treated with vincristine sulfate, cyclophosphamide, and prednisone; 1 was treated with chlorambucil and prednisone. Survival time ranged from 2 to 2,120 days (median, 50 days). Nine cats achieved complete remission (remission time ranged from 30 to 1,700 days; median, 213 days), 2 achieved partial remission, and 17 failed to respond to chemotherapy. Sex, FeLV status, hematocrit, serum total protein concentration, site and extent of gastrointestinal involvement, and clinical stage were not found to be associated with survival time. CLINICAL IMPLICATIONS: Cats with alimentary lymphoma are poorly responsive to treatment with vincristine, cyclophosphamide, and prednisone; however, a small subset of cats may have long survival times.

Early postoperative ultrasonographic evaluation of incisional sites in dogs: 15 cases (1990-1992).

Ultrasonography of the surgical sites of 15 dogs was performed 3 to 8 days after they underwent major orthopedic surgical procedures. Eight dogs were suspected of having incision-site complications on the basis of localized signs of pain, heat, or swelling and clinical signs of pyrexia, lethargy, or anorexia. Seven dogs had apparently normal healing of the incision. Ultrasonography was used to assess and compare the character of fluid accumulation, to detect fluid accumulation associated with evidence of distal enhancement, and to evaluate gas accumulation and disruption of muscle fibers. Ultrasonography of the 8 dogs with complications of the incision site revealed fluid accumulation (8 dogs), distal enhancement associated with fluid accumulations (2), disruption of muscle fibers (1), and gas accumulation (1). Ultrasonography of the 7 dogs with apparently normal healing of the incisions revealed fluid accumulations (2 dogs), fluid between fascial planes (4), disruption of muscle fibers (1), and gas accumulation (1). Aspirates of fluid were obtained from 7 dogs with suspected incision-site infection. Analysis of results of cytologic evaluation or bacterial culturing confirmed infection in 6 dogs and indicated that 1 dog had a sterile hematoma. Ultrasonography is a sensitive technique for the detection and localization of fluid accumulations; however, the detection of fluid accumulations was not limited to dogs with incision-site complications. Fluid accumulations can be evaluated by use of ultrasound-guided needle aspiration, which has few associated negative side-effects. During the early postoperative period, results for fluid evaluation of samples obtained by use of accurately placed aspiration needles can be used to serve as a guide for further treatment.

Radiographic features of canine hyperadrenocorticism caused by autonomously functioning adrenocortical tumors: 23 cases (1978-1986).

Radiographic features of 23 dogs with functioning adrenocortical tumors are described. In 56% of the dogs, radiographic detection of adrenomegaly, with or without calcification, was an aid in the diagnosis of adrenocortical neoplasia. Adrenal gland calcification did not distinguish adrenocortical adenoma from carcinoma.