MYELOPATHY SECONDARY TO AORTOCAVAL FISTULA IN A CAT

A 15-month-old neutered male cat was presented for progressive paraparesis of 3 months' duration and suspected cardiomegaly. Neuroanatomical localization was a T3-L3 myelopathy. On abdominal ultrasound, an anomalous vessel with turbulent blood flow was identified arising from the caudal vena cava. Myelography showed a bilateral ventrolateral extradural spinal cord compression from T12 to L4. Nonselective angiography and contrast-enhanced computed tomography clearly indicated a vascular complex and vena caval aneurysm with an engorged internal vertebral venous plexus. Surgical occlusion of the anomalous vessels was unsuccessful.     

HYDROTHORAX SECONDARY TO A PERINEPHRIC PSEUDOCYST IN A CAT

Hydrothorax was identified in a 14-year-old Siamese cat with a pre-existent perinephric pseudocyst. The pleural fluid was classified as a low-protein transudate. Intrapseudocystic scintigraphy confirmed a direct communication between the pseudocyst and the pleural space. The hydrothorax resolved following pseudocystectomy and unilateral nephrectomy, demonstrating that the psendocyst caused the hydrothorax.     

MINERALIZED ARTERIOSCLEROSIS IN A CAT

In radiographs of a domestic short haired cat of unknown age, mineralization was identified in the pulmonary parenchyma, peripheral pulmonary vessels, the aortic outflow tract, aortic valve, celiac artery, cranial mesenteric artery, and the internal and external iliac arteries. The diffuse arterial mineralization was characterized histopathologically as arteriosclerosis. This is the first report of mineralized arteriosclerosis in a cat with corresponding radiographic signs. The arteriosclerosis is thought to be due to systemic hypertension but a definitive cause for the profound mineralization was not found. Causes of soft tissue mineralization are reviewed.     

IDIOPATHIC MEDIASTINAL CYST IN A CAT

A thirteen year old neutered female Domestic Shorthair cat with oral squamous cell carcinoma was noted to have a cranial mediastinal mass on survey thoracic radiographs. Fluoroscopic aspiration was performed and cystic fluid was obtained which was clear colorless, and devoid of cells, with a specific gravity of 1.005 and protein <2.5 mg/dl. On postmortem examination, a unilocular cyst was identified originating from the external lateral surface of the cranial mediastinum. Histologically, the cyst lining was nonciliated and resembled mesothelium. These findings differentiate this cyst from previously reported branchial cysts in cats where the cysts were multiloculated, the cyst fluid was mucinous and cellular, and the cysts were lined by ciliated columnar epithelial cells.     

TRUE DIAPHRAGMATIC HERNIA IN A CAT

A report of a cat with a true diaphragmatic hernia in which only falciform fat had herniated is pressented. The lession was misinterpreted as a pulmonary mass. Additional radiographic studies which may have been of diagnostic benefit are briefly discussed.     

CALCIUM OXALATE URETEROLITH IN A CAT

A 4-year-old cat was presented for polyuria and polydipsia. Unilateral hydronephorosis and hydroureter was diagnosed on ultrasound examination of the abdomen, and right ureteral calculi were seen in survey abdominal radiographs. Intravenous urography confirmed hydronephrosis and indicated poor renal funttion in the right kidney. Surgical removal of the ureteral calculus improved right renal function. Analysis of the calculus indicated composition of calcium oxalate, an uncommon calculus in cats.     

BILOBED GALLBLADDER IN A CAT: ULTRASONOGRAPHIC APPEARANCE

A five-month-old male domestic shorthair cat presented with a history of vomiting for 4 days. An ultrasound examination of the abdomen was performed as part of the diagnostic workup. The gallbladder appeared to be bilobate. The cat died the following day from renal failure. At necropsy, a bilobed gallbladder was confirmed and considered to be a congenital anomaly unrelated to the cat's death.     

IMAGING DIAGNOSIS—EXTRAHEPATIC BILIARY TRACT OBSTRUCTION SECONDARY TO A DUODENAL FOREIGN BODY IN A CAT

A 13-month-old, neutered female domestic shorthaired cat was evaluated for vomiting, anorexia, and lethargy. The cat was icteric and hyperbilirubinemic. Radiographically a partially radiolucent proximal duodenal foreign body was suspected. Ultrasonographically, there was a foreign body at the level of the duodenal papilla and dilation of the common bile duct and cystic duct; a diagnosis of extrahepatic biliary tract obstruction secondary to a duodenal foreign body was made. Sonographic findings were confirmed at surgery and a duodenal foreign body was removed. This information defines duodenal foreign body as a cause of extrahepatic biliary obstruction in cats.     

IMAGING DIAGNOSIS: FIBRODYSPLASIA OSSIFICANS PROGRESSIVA IN A CAT

A 1‐year‐old female cat was presented for progressive alopecia, gait abnormalities, and stiffness. Radiography demonstrated multiple calcified lesions within the soft tissues of the cervical and thoracic spine, shoulder, and limbs. Postmortem computed tomography provided more detailed information on the distribution, pattern, and extension of lesions. In addition, computed tomography helped guide sample selection for histopathology. The final diagnosis was fibrodysplasia ossificans progressiva. This is a rare disorder of unknown etiology, characterized by fibrosis and heterotopic bone formation in connective tissues. To the authors’ knowledge, this is the first report describing this disease in a European cat.     

ULTRASONOGRAPHIC DIAGNOSIS-SMALL BOWEL INFARCTION IN A CAT

An 8-year-old, domestic short hair cat with a known history of hypertrophic cardiomyopathy and previous aortic thromboembolism was presented for 24 h of vomiting and pyrexia. Initial abdominal radiographs were unremarkable. On an upper gastrointestinal series, delayed gastric emptying and prolonged small intestinal transit time were found. An initial abdominal ultrasound revealed a focal region of aperistaltic small intestine with mild wall thickening, however, intestinal wall layering in this area appeared normal. By 72 h, there was a diffusely hypoechoic portion of thickened small bowel (0.51 cm) with loss of the normal layering and hyperechoic mesentery surrounding this segment of bowel. A small bowel infarction and focal peritonitis were suspected and confirmed at surgery.     

IMAGING DIAGNOSIS—EXTRAHEPATIC BILIARY TRACT OBSTRUCTION SECONDARY TO A BILIARY FOREIGN BODY IN A CAT

An 11‐year‐old, neutered female British Shorthair cat was referred with a 4‐week history of abdominal pain and vomiting. Abdominal ultrasonography revealed a dilated common bile duct containing a spindle‐shaped structure with several reflecting interfaces. Differentials that were considered included an intraluminal foreign body, or helminth parasites within the common bile duct. Surgical exploration of the abdominal cavity demonstrated the presence of two grass awns obstructing the common bile duct. Anomalies of the portal vasculature were noted during surgery and were considered an incidental finding. The clinical signs resolved following surgical removal of the grass awns.     

DISSEMINATED HISTOPLASMOSIS WITH OSSEOUS LESIONS IN A CAT WITH FELINE LYMPHOSARCOMA

A cat was presented with a non-weight-bearing lameness of the left thoracic limb, painful joints and lymphadenopathy. Marked bilateral osteolysis of the distal radial and ulnar metaphyses was detected radiographically. A post mortem diagnosis of disseminated histoplasmosis and feline lymphosarcoma was made.     

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.     

INFLAMMATORY POLYP IN THE MIDDLE EAR WITH SECONDARY SUPPURATIVE MENINGOENCEPHALITIS IN A CAT

A 15-month-old male Maine Coon Cat presented with persistent auricular discharge and progressive head tilt, ataxia, and loss of blink on the right side. Using computed tomography a hyperattenuating, contrast-enhancing material within a thickened right tympanic bulla and contrast enhancement of the adjacent cerebellum were identified. Marked suppurative inflammation was identified on cerebrospinal fluid analysis with no growth on bacterial culture. Ventral bulla osteotomy was performed to remove a soft tissue mass, and an inflammatory polyp with chronic severe suppurative inflammation was confirmed using histology. Staphylococcus auricularis was grown on aerobic culture and Fusobacterium necrophorum and Peptostreptococcus anaerobius were grown on anaerobic culture. The cat was treated for 10 weeks with amoxicillin/clavulinic acid and metronidazole. Dramatic improvement in body weight, appetite, energy level, balance, and resolution of right-sided facial paralysis were noted, but the cat retained a head tilt.     

IMAGING DIAGNOSIS—IMAGING AND HISTOPATHOLOGIC CHARACTERISTICS OF A VERTEBRAL HAMARTOMA IN A CAT

A 9‐month‐old domestic shorthair cat had progressive ambulatory paraparesis, proprioceptive ataxia, and thoracolumbar hyperesthesia. An extradural mass affecting the left pedicle and lamina of the second lumbar vertebra (L2) causing marked spinal cord impingement was identified in magnetic resonance (MR) images. The mass was predominantly calcified in computed tomographic (CT) images. A hemilaminectomy was performed to resect the mass. Clinical signs were greatly improved at 12‐month follow‐up. The histopathologic diagnosis was vascular hamartoma. To our knowledge, this is the first report describing the MR characteristics of a vascular hamartoma associated with the vertebral column.     

IATROGENIC BILOMA (BILIARY PSEUDOCYST) IN A CAT WITH HEPATIC LIPIDOSIS

An eight-year-old neutered female domestic longhair cat was presented with icterus and a palpable cranial abdominal mass. The cat had undergone an open biopsy of the liver two years previously. Abdominal radiographic findings included a solitary soft tissue mass originating from the right cranial hepatic region. An anechoic cystic structure was identified on ultrasound examination. Surgical exploration revealed the cyst to be filled with bile. The fibrous capsule of the cyst originated in the liver. Severe hepatic lipidosis was also present. It is believed that the bilorna was a complication of the previous hepatic biopsy and not a sequela of hepatic lipidosis.     

EVALUATION OF LYMPHOMA IN A CAT USING 99mTc-SESTAMIBI

This report describes the evaluation of cutaneous lymphoma in a cat using 99mTc-sestamibi. A mass in the left pes with extension to the left popliteal lymph node was diagnosed as B-cell lymphoma. Thoracic and abdominal radiography and abdominal ultrasound were unremarkable. Scintigraphy using 99mTc-sestamibi confirmed the lesion was confined to the left hind leg, and the leg was amputated. The cat made a full recovery.     

ULTRASONOGRAPHY OF INTESTINAL MAST CELL TUMORS IN THE CAT

The sonographic features of intestinal mast cell tumors (MCT) were reviewed in 14 cats. The mean age was 13.4 ± 2.5 years. There were 16 focal intestinal tumors and one diffuse submucosal infiltrate. The most common pattern was focal, hypoechoic wall thickening that was noncircumferential and eccentric (9/16 tumors) or circumferential, asymmetric, and eccentric (5/16 tumors). Nine of the cats had lesions in the jejunum or duodenum, four were at the ileocecocolic junction, and one cat had a colonic mass. Six MCTs had altered but not loss of wall layering, and the most commonly affected layer on ultrasound examination was the muscularis propria. Nine cats had enlarged abdominal lymph nodes, and seven were due to metastatic disease. Metastatic disease was not routinely detected by ultrasound in the liver (1/4 cats) or the spleen (0/3 cats). Concurrent small cell (T cell) lymphoma was present in four of 14 cats (29%).     

IMAGING DIAGNOSIS—MAGNETIC RESONANCE IMAGING FINDINGS IN A CAT WITH SYSTEMIC REACTIVE ANGIOENDOTHELIOMATOSIS

A 10‐year‐old, castrated male domestic short‐haired cat was presented with an acute history of seizures, lethargy, anorexia, vomiting, and dyspnea. Magnetic resonance imaging of the brain showed multifocal areas of gray matter T2‐weighted hyperintensity. The lesions did not enhance with intravenous contrast. The cat was diagnosed at necropsy with feline systemic reactive angioendotheliomatosis, a rare vascular proliferative disorder for which a treatment has not yet been identified. This report is the first to describe associated magnetic resonance imaging changes for this disease.