Gray-scale ultrasonography in the diagnosis of adrenal neoplasia in dogs: six cases (1981-1986)

In addition to survey abdominal radiography, 2-dimensional gray-scale ultrasonography was utilized as a non-invasive imaging mode in 6 dogs with adrenal neoplasia. Ultrasonography was a safe method of obtaining information about the organ of involvement, extra-adrenal extent of disease, vascular invasion or compression, and internal architecture of abdominal masses in the area of the adrenal gland. The data obtained ultrasonographically was determined to be useful in diagnosing adrenal neoplasia.     

Pyloric outflow obstruction secondary to sclerosing encapsulating peritonitis in a dog

A 6-year-old, male neutered mixed breed dog was presented emergently with a three-week history of hyporexia, vomiting, diarrhoea and weight loss. Upon examination, the patient was dull, had generalised muscle atrophy, moderate abdominal pain and a mild amount of peritoneal effusion. A fluid-filled, distended, corrugated small bowel with marked gastroparesis and moderate peritoneal effusion was noted on abdominal ultrasonography. Endoscopy revealed hyperaemic and friable mucosa and a subjectively narrowed pylorus. Emergency exploratory celiotomy was performed due to worsening patient condition and revealed thick, diffuse, fibrous adhesions of the abdominal cavity. Based on these findings, sclerosing encapsulating peritonitis (SEP) was suspected. A large mass of omentum adjacent to the greater curvature of the stomach had caused a pyloric outflow obstruction. Adhesiolysis was attempted but was unsuccessful due to the friability of the small intestines. The dog was humanely euthanased under anaesthesia. A diagnosis of SEP was confirmed via necropsy. No underlying cause was identified. This is the first known case of a pyloric outflow obstruction secondary to SEP in a dog. Although rare, this condition should be considered as a differential for dogs with signs of a pyloric outflow obstruction with concurrent ascites and abdominal pain, hyporexia, vomiting and diarrhoea.     

IMAGING DIAGNOSIS—DISSEMINATED PERITONEAL LEIOMYOMATOSIS IN A DOG

A 17‐month‐old male Labrador retriever presented for evaluation of an abdominal mass felt during abdominal palpation. Multiple variably sized cystic masses were identified on sonographic and radiographic images. Exploratory laparotomy revealed multiple peritoneal masses that exhibited atypical contractions and lacked an identifiable organ of origin. Histology and immunohistochemistry of multiple surgically excised masses was consistent with benign tumors of smooth muscle origin (leiomyomas). The presence of multiple peritoneal leiomyomas in this dog is consistent with disseminated peritoneal leiomyomatosis. Two years after diagnosis and multiple surgical interventions, continual insidious enlargement of leiomyomas was identified on ultrasound and CT.     

A RETROSPECTIVE STUDY ON THE SONOGRAPHIC FINDINGS OF ABDOMINAL CARCINOMATOSIS IN 14 CATS

A retrospective review was performed on 14 cats with histology- or cytology-proven carcinomatosis. The mean age was 12.7 years with a median of 11 years. The diagnosis of carcinomatosis was made by histology in 11 cats and cytology in three cats. Twelve cats had cytologic examination of the peritoneal free fluid and seven cats (58.3%) had evidence of malignant cells. The primary tumor site was determined in 13 cats. The most common organ locations for the primary tumor were the liver (n = 5), pancreas (n = 3), and small intestine (n = 3). Other sites were stomach and spleen in one cat each. Epithelial cell neoplasia was the primary tumor type in 11 cats. Two cats had abdominal lymphomatosis and one cat had abdominal sarcomatosis secondary to metastatic hemangiosarcoma. Free peritoneal fluid and masses in the connecting peritoneum were found in all cats (100%). Additional findings included primary or metastatic masses in abdominal organs in 10 cats (71.4%), lymph node enlargement in five cats (35.7%), pleural effusion in three cats (21.4%), parietal peritoneal masses in two cats (14.3%), and visceral peritoneal masses in one cat (7.1%). Masses in the connecting peritoneal may be a very specific finding for carcinomatosis in cats, especially with a concurrent abdominal neoplastic mass. Parietal and visceral peritoneal masses, while uncommon in this series of cats, have not been reported for other diseases and seem to strongly support a diagnosis of carcinomatosis.     

Canine Hyperadrenocorticism Due to Adrenocortical Neoplasia: Pretreatment Evaluation of 41 Dogs

This retrospective study identifies parameters that might separate dogs with hyperadrenocorticism caused by adrenocortical tumors from dogs with pituitary-dependent hyperadrenocorticism. Further, an attempt was made to identify factors that could separate dogs with adrenocortical adenomas from dogs with carcinomas. The records of 41 dogs with hyperadrenocorticism caused by adrenocortical neoplasia were reviewed. The history, physical examination, urinalysis, hemogram (CBC), chemistry profile adrenocorticotrophic hormone (ACTH) stimulation and low dose dexamethasone test results were typical of the nonspecific diagnosis of hyperadrenocorticism. The preceding information on the 41 dogs with adrenocortical tumors was compared with that from 44 previously diagnosed pituitary-dependent hyperadrenocorticoid dogs. There was no parameter which aided in separating these two groups of dogs. Thirty dogs with adrenocortical tumors were tested with a high-dose dexamethasone test and none had suppressed plasma cortisol concentrations 8 hours after IV administration of 0.1 mg/kg of dexamethasone. In 29 of the 41 adrenal tumor dogs, plasma endogenous ACTH was not detectable on at least one measurement (less than 20 pg/ml). The remaining 12 dogs from this group had nondiagnostic concentrations (20-45 pg/ml). Thirteen of 22 dogs (59%) with adrenocortical carcinomas had adrenal masses identified on abdominal radiographs and seven of 13 dogs (54%) with adrenocortical adenomas had radiographically visible adrenal masses. Thirteen of 17 adrenocortical carcinomas (76%) and five of eight adenomas (62%) were identified with ultrasonography. Radiographs of the thorax and ultrasonography of the abdomen identified most of the dogs (8 of 11) with metastatic lesions.(ABSTRACT TRUNCATED AT 250 WORDS)     

Diagnostic ultrasonography in cattle with abdominal fat necrosis

This study describes the ultrasonographic findings in 14 cows with abdominal fat necrosis. Ultrasonography of the abdomen revealed the presence of heterogeneous hyperechoic masses and hyperechoic omentum with localized masses floating in a hypoechoic peritoneal fluid. A hyperechogenic rim was imaged around both kidneys. The intestines were coated with hyperechoic capsules and the intestinal lumens were constricted. Ultrasonographic examination of the pancreatic parenchyma showed an overall increased echogenicity which was homogenously distributed in 3 cases. A diagnosis of abdominal fat necrosis was made with ultrasound-guided biopsy of the echogenic masses, and thereafter at postmortem examination. Results from this study demonstrate the efficacy of ultrasonography as an imaging modality for antemortem diagnosis of abdominal lipomatosis in cattle. To the authors' knowledge, this study is the first that illustrates ultrasonographic findings in cattle affected with abdominal lipomatosis.     

Ultrasonographic evaluation of renal parenchymal diseases in dogs: 32 cases (1981-1986)

The medical records of 32 dogs with microscopically proven renal parenchymal disease were evaluated to characterize the associated ultrasonographic patterns and to assess the contribution of ultrasonography to the diagnosis and management in each case. Ultrasonography provided additional information on internal renal architecture in 18 dogs with radiographic evidence of structural abnormality. Ultrasonography determined the renal origin of 2 abdominal masses, defined the extent and distribution of neoplastic disease in 6 dogs, and identified kidneys not seen on survey radiographs or excretory urograms in 5 dogs because of decreased abdominal contrast or poor function. The ultrasonographic patterns were most specific for focal and multifocal or diffuse neoplasia. Ultrasonographic findings were least specific for diffuse parenchymal disease without architectural disruption such as glomerulo/interstitial nephritis, renal tubular necrosis, and nephrocalcinosis. In these cases, biopsy was recommended. Six interpretive errors were made. Four of these errors were related to the overestimation of renal pelvic and diverticular size because of confusion with medullary papilla. Two errors occurred in the diagnosis of renal lymphosarcoma, one of which was interpreted to be pyelonephritis. The other was an interpretive dilemma because of absence of hypoechoic multifocal nodules. Renal tubular necrosis was confirmed in this case.     

ULTRASONOGRAPHIC FINDINGS IN 13 HORSES WITH LYMPHOMA

Ultrasonography and radiography are commonly used for staging of lymphoma in horses, however there is little published information on imaging characteristics for horses with confirmed disease. The purpose of this retrospective, case series study was to describe ultrasonographic and radiographic findings for a group of horses with a confirmed diagnosis of lymphoma. A total of 13 horses were sampled. Lymphadenopathy (8/13), peritoneal effusion (6/13), splenic (6/13), and hepatic (5/13) lesions were the most frequently identified. The predominant splenic and hepatic ultrasonographic lesions were hypoechoic nodules, organomegaly, and changes in echogenicity. Digestive tract lesions were detected in three horses and these included focal thickening and decreased echogenicity of the small (2/13) and large intestinal (2/13) wall. Thoracic lesions were predominantly pleural effusion (4/13), lymphadenopathy (4/13), and lung parenchymal changes (3/13). Enlarged lymph nodes were detected radiographically (4/13) and/or ultrasonographically (2/13) in the thorax and ultrasonographically in the abdomen (7/13) and in the caudal cervical region (4/13). Findings supported the use of abdominal and thoracic ultrasonography for lymphoma staging in horses. Ultrasound landmarks for localizing cecal and caudal deep cervical lymph nodes were also provided.     

Gastrointestinal stromal tumors and leiomyomas in the dog: a histopathologic,immunohistochemical, and molecular genetic study of 50 cases

Fifty canine gastrointestinal (GI) mesenchymal tumors were examined to determine the occurrence of leiomyomas (LM) and GI stromal tumors and to compare their clinicopathologic features. Twenty-one tumors (42%) were histologically reclassified as gastrointestinal stromal tumors (GISTs) and 29 tumors (58%) as LMs on the basis of their histologic similarity with homologous human tumors. The GISTs occurred equally in males and females, with a mean age of 11 years (range 5-14 years). Five GISTs (24%) were associated with clinical signs and six (29%) had metastasis in liver or abdominal cavity. The GISTs occurred in large intestine (10, 48%), small bowel (six, 29%), stomach (four, 19%), and mesentery of small intestine (one, 5%). Histologically, they were highly cellular spindle, or less commonly epithelioid tumors with mitotic rates ranging from 0 to 19 per 10 HPF. Eleven tumors (52%) were positive for CD117 (KIT); seven (33%) were positive for smooth muscle actin but none for desmin and S-100 protein. Sequences of KIT exon 11, often mutated in human GISTs, were evaluated from four GISTs. Deletion of Try556-Lys557 coexisting with duplication of Gln555 in one case of GIST and T to C transition resulting in substitution of Pro for Leu575 in another were identified. The LMs occurred predominantly in males (82%) with a mean age of 11 years (range 8-17 years). Nine tumors (31%) had associated clinical signs. They occurred in the stomach (22, 76%), esophagus (four, 14%), and intestines (three, 10%); all were paucicellular, had no mitoses, and were composed of mature smooth muscle cells. Twenty-eight (97%) were positive for smooth muscle actin and 18 (62%) for desmin but none for CD117 and S-100. Both GISTs and true LMs occur in the GI tract of dogs. Both tumors have distinctive pathologic features.     

Echocardiographic results and clinical considerations in dogs with right atrial/auricular masses

The case records of 26 dogs with pericardial effusion were examined. Sixteen dogs with confirmed right atrial/auricular masses were found. Eighteen masses were identified, of which 16 were confirmed as hemangiosarcomas. Eleven dogs had an abnormal mass detected during the echocardiographic examination, and tumor location was correctly predicted in nine of the 11 dogs. Six of seven tumors, which were not detected during the echocardiogram, were located in the right auricle. Pericardial effusion was apparently not necessary for the echocardiographic detection of a right atrial/auricular mass. Of ten dogs with pericardial effusion due to causes other than a cardiac mass, one abnormal mass-like lesion was seen during echocardiographic examination.     

Color and power Doppler ultrasonography for characterization of splenic masses in dogs

Benign and malignant splenic masses can appear similar on B-mode imaging, making ultrasound sensitive but not specific in their diagnosis. Our goal was to characterize color and/or power Doppler characteristics of vasculature within and adjacent to a splenic mass, which would distinguish benign vs. malignant lesions. The hypothesis was that malignant splenic masses will have altered vascular patterns compared with benign masses. Color and power Doppler cineloops evaluating the vasculature within the mass and normal splenic parenchyma were obtained in sagittal and transverse planes using a standardized protocol. Categories of evaluation included presence of peritoneal effusion, a large aberrant or tortuous vessel within the mass, relative blood flow within the mass compared with normal parenchyma, and path of vessels in the adjacent parenchyma entering into the mass. All patients had histopathologic or definitive cytologic diagnosis. Thirty-one dogs were included. There were 13 malignant masses and 18 were benign. Peritoneal effusion was significantly associated with malignancy (P = 0.0007). Presence of an aberrant or tortuous vessel within the mass was nearly significant (P = 0.059). There was no significant difference in any of the color or power Doppler blood flow evaluations. Ultrasonographic findings of a splenic mass and peritoneal effusion may indicate malignancy. The presence of an aberrant vessel within a splenic mass could suggest malignancy; however more data are needed.     

EMPHYSEMATOUS HEPATIC ABSCESS ASSOCIATED WITH TRAUMA, NECROTIC HEPATIC NODULAR HYPERPLASIA AND ADENOMA IN A DOG: A CASE HISTORY REPORT

A 13-year-old male Setter-Springer crossbred dog was presented with signs of acute peritonitis three days after blunt abdominal trauma. In abdominal radiographs, a bubbly accumulation of gas in the central and cranioventral parts of the liver silhouette and mild peritoneal effusion were seen. At laparatomy, firm, necrotic, nodular hepatic masses containing gas were found to be ruptured. The histologic diagnoses were hepatic adenoma with hepatic necrosis and nodular hepatic hyperplasia. The pathogenesis of hepatic abscessation and the radiographic differential diagnosis of extraluminal abdominal gas are discussed.     

ULTRASONOGRAPHIC APPEARANCE AND ETIOLOGY OF CORRUGATED SMALL INTESTINE

An ultrasound pattern of corrugated, and sometimes thickened, bowel wall has been associated with pancreatitis and small intestinal lymphangiectasia. In a retrospective study, records of dogs and cats with an ultrasound diagnosis of corrugated bowel were examined for age, breed, gender, presenting complaint, abdominal radiographic results, and final diagnosis. Eighteen dogs and six cats had an ultrasound diagnosis of corrugated bowel. The final diagnosis was pancreatitis (12 of 24), peritonitis (4 of 24), enteritis (2 of 24), pancreatic neoplasia (2 of 24), diffuse abdominal neoplasia (1 of 24), lymphocytic-plasmacytic enteritis (1 of 24), thrombosis/infarction (1 of 24), and protein-losing enteropathy and acute renal failure (1 of 24). The presence of bowel wall corrugation, although a nonspecific finding, should alert one-to the possibility of pancreatitis, enteritis, peritonitis, neoplasia, or bowel wall ischemia.     

Ultrasonography and surgery of canine biliary diseases

Findings of hepatic and gallbladder ultrasonography were analyzed in 12 dogs with gallbladder and/or extrahepatic biliary tract obstruction and compared with the results of exploratory laparotomy. Hepatic ultrasonography demonstrated normal liver in 2 dogs and hepatic abnormalities in 10 animals. The following ultrasonographic diagnoses were established compared to surgical findings: gallbladder obstruction caused by bile sludge (correct/incorrect: 1/2, surgical diagnosis: choleliths in one case), gallbladder obstruction caused by neoplasm (0/1, surgical diagnosis: mucocele), gallbladder and extrahepatic biliary tract obstruction due to choleliths (3/3), extrahepatic biliary tract obstruction caused by pancreatic mass (1/1) and small intestinal volvulus (1/1). Bile peritonitis caused by gallbladder rupture (4/4) was correctly diagnosed by ultrasound, aided with ultrasonographically-guided abdominocentesis and peritoneal fluid analysis. Rupture of the gallbladder should be suspected in the presence of a small, echogenic gallbladder or in the absence of the organ together with free abdominal fluid during ultrasonography. Laparotomy was correctly indicated by ultrasonography in all cases. However, the direct cause of obstruction could not be determined in 2 of the 12 dogs by ultrasonography alone.     

Postoperative ultrasonographic appearance of uncomplicated enterotomy or enterectomy sites in dogs

The ultrasonographic findings in 20 dogs with 25 healing enterotomy and enterectomy sites resulting from the removal of foreign material or correction of intussusceptions are presented. In this prospective study, dogs had preoperative abdominal ultrasound examinations followed by sequential sonographic examinations on the first, third, sixth, and 10th days postenterotomy or enterectomy with an additional sonographic examination after 20 days postoperatively. Documented sonographic features included length and maximal intestinal wall thickness of the enterotomy or enterectomy sites, echogenicity of omental/mesenteric fat, amount of free gas and abdominal effusion, and gastrointestinal motility. Sonographically, 57% of enterotomies and 100% of enterectomies were visualized. Pneumoperitoneum, hyperechoic omental/mesenteric fat, and abdominal effusion did not appreciably hamper evaluation of the intestinal surgical site. Absent wall layering at the surgical site was noted in 96% of dogs at day 1 postoperatively. At the final sonographic examination, wall layering remained altered to absent in 100% of dogs and normal thickness was noted in only 20% of dogs. The median maximal wall thickness was 7 and 8 mm for enterotomies and enterectomies respectively, which occurred between days 1 and 3 and days 3 and 6 postoperatively. Effusion and increased echogenicity of omental/mesenteric fat localized to the surgical site were noted in 42% and 60% of dogs respectively at day 1 postoperatively, with resolution noted between days 3 and 10 postoperatively in 92% and 80% of dogs. Generalized abdominal effusion and pneumoperitoneum were seen in 100% of dogs immediately postoperatively and resolved in 80% by day 10.     

ULTRASONOGRAPHIC FINDINGS IN DOGS AND CATS WITH GASTROINTESTINAL PERFORATION

A retrospective study was performed to evaluate the sonographic features of gastrointestinal (GI) perforation in dogs and cats. Sonographic findings in 19 animals (14 dogs and 5 cats) included regional bright mesenteric fat (19), peritoneal effusion (16), fluid-filled stomach or intestines (12), GI wall thickening (11), presence of free air (9), loss of GI wall layering (9), regional lymphadenopathy (8), reduced GI motility (7), pancreatic changes (4), corrugated intestines (4), presence of a mass (3), presence of a foreign body (3), and mineralization of the gastric wall (1). In 14 patients, "perforation" was listed as a differential diagnosis by the sonographer. Abdominal radiographs and radiographic reports were available for 14 patients. Radiographic findings were decreased serosal detail (12), free air (8), peritoneal contrast medium (1), and suspected foreign body (1). GI perforation was listed as radiographic diagnosis in eight patients, seven of which had evidence of pneumoperitoneum, and one had leakage of contrast material on an upper GI study. In 9/14 patients with radiography, "GI perforation" was listed as a sonographic diagnosis. In three patients in which free air was diagnosed sonographically, radiographs were either not available (2) or the presence of free air was not detected at presentation (1). Peritoneal fluid analysis was performed in nine patients, five of which were identified as septic inflammation, and the remaining four were classified as neutrophilic inflammation with no etiologic agent identified. The histologic or surgical diagnoses were as follows: three intestinal surgical dehiscence; one percutaneous endoscopic gastrostomy tube site leakage; one duodenal adenocarcinoma; one ileocolic lymphoma; one trichobezoar; one ascarid impaction; and one bobby pin foreign body. In the remaining 10 patients, a focal area of gastric/intestinal ulceration or transmural necrosis with perforation was identified without evidence of an underlying cause.     

ULTRASOUND CRITERIA AND GUIDED FINE‐NEEDLE ASPIRATION DIAGNOSTIC YIELDS IN SMALL ANIMAL PERITONEAL,MESENTERIC AND OMENTAL DISEASE

Peritoneal, mesenteric, and omental diseases are important causes of morbidity and mortality in humans and animals, although information in the veterinary literature is limited. The purposes of this retrospective study were to determine whether objectively applied ultrasound interpretive criteria are statistically useful in differentiating among cytologically defined normal, inflammatory, and neoplastic peritoneal conditions in dogs and cats. A second goal was to determine the cytologically interpretable yield on ultrasound‐guided, fine‐needle sampling of peritoneal, mesenteric, or omental structures. Sonographic criteria agreed upon by the authors were retrospectively and independently applied by two radiologists to the available ultrasound images without knowledge of the cytologic diagnosis and statistically compared to the ultrasound‐guided, fine‐needle aspiration cytologic interpretations. A total of 72 dogs and 49 cats with abdominal peritoneal, mesenteric, or omental (peritoneal) surface or effusive disease and 17 dogs and 3 cats with no cytologic evidence of inflammation or neoplasia were included. The optimized, ultrasound criteria‐based statistical model created independently for each radiologist yielded an equation‐based diagnostic category placement accuracy of 63.2–69.9% across the two involved radiologists. Regional organ‐associated masses or nodules as well as aggregated bowel and peritoneal thickening were more associated with peritoneal neoplasia whereas localized, severely complex fluid collections were more associated with inflammatory peritoneal disease. The cytologically interpretable yield for ultrasound‐guided fine‐needle sampling was 72.3% with no difference between species, making this a worthwhile clinical procedure.     

ULTRASONOGRAPHIC FEATURES OF CANINE GASTROINTESTINAL STROMAL TUMORS COMPARED TO OTHER GASTROINTESTINAL SPINDLE CELL TUMORS

Canine gastrointestinal stromal tumors (GISTs) are a recent subtype of gastrointestinal spindle cell tumor recognized with the increasing use of immunohistochemistry. To our knowledge, no imaging features have been described in immunistochemically confirmed canine GISTs. The objective of this retrospective, cross‐sectional study was to describe ultrasonographic features of canine GISTs compared with other spindle cell tumors. Thirty‐seven dogs with an ultrasonographically visible gastrointestinal mass and a histopathologic diagnosis of spindle cell neoplasia were examined. Immunohistochemistry staining was performed for retrieved tissue samples to further differentiate the tumor type and each sample was interpreted by a single veterinary pathologist. Ultrasonographic features recorded examined included mass echogenicity, homogeneity, presence of cavitation, layer of origin, bowel wall symmetry, and loss of wall layering, location, size, vascularity, and evidence of perforation or ulceration. Tumor types included 19 GISTs, eight leiomyosarcomas, six leiomyomas, and four nonspecified sarcomas. Gastrointestinal stromal tumors were significantly more likely to be associated (P < 0.03) with abdominal effusion than other tumor types. There was overlap between the anatomical locations of all tumors types with the exception of the cecum where all eight tumors identified were GISTs. Besides location, there were no unique ultrasound features of GISTs that would allow distinction from other gastrointestinal spindle cell tumors. Similar to previous studies, GISTs appeared to be the most common spindle cell tumor associated with the cecum in our sample of dogs. The high frequency of abdominal effusion with GIST's was of unknown etiology could possibly have been due to septic peritonitis.     

ULTRASONOGRAPHIC FEATURES OF INTESTINAL ENTRAPMENT IN DOGS

The clinical and ultrasonographic features of postoperative intestinal entrapment were assessed in five dogs. Four had vomiting and lethargy, and one had peracute collapse and hematochezia. Ultrasonographic findings in four of five dogs were similar, being characterized by focally hyperechoic mesentery and abdominal effusion, surrounding a single loop of amotile and dilated intestine. In some dogs, the affected intestinal loop had a thickened or corrugated wall, or alteration of wall layering. In one dog, the site of entrapment could be directly visualized. In the most severely affected dog, a large volume of echogenic peritoneal effusion was present, as well as fluid dilation of multiple intestinal loops. The ultrasonographic appearance of intestinal entrapment is similar to that of intestinal perforation or infarction by other causes.