Acute mitral regurgitation with papillary muscle rupture in a dog

Papillary muscle rupture is uncommon in the dog. Two-dimensional echocardiography provides a rapid, noninvasive test in the diagnosis of acute, severe mitral regurgitation resulting from papillary muscle rupture. This report illustrates the usefulness of echocardiography to determine the cause of acute mitral regurgitation.     

Tracheal rupture in a dog

A two-year-old male Retriever-crossbred dog was presented with progressive subcutaneous emphysema and pronounced dyspnoea following a cervical impact injury sustained ten days previously. Radiography revealed an almost complete transection of the cervical trachea and an associated pneumomediastinum and unilateral pneumothorax. The damaged tracheal segment was resected and anastomosis performed following drainage of the pneumothorax. The dog made an uneventful recovery with no evidence of stenosis detectable at the site of the repair six months post-operatively.     

Bilateral patellar fracture in a dog

A 4-year-old Border Collie bitch was presented with a transverse fracture of both patellae. The relevant clinical findings and subsequent surgical treatment of the fractures are described. The occurrence and management of patellar fractures in dogs are discussed.     

Bilateral xanthine nephrolithiasis in a dog

Xanthinuria is an uncommon metabolic disorder clinically manifested as uroiithiasis. There are two forms of the disease, Congenital and iatrogenic. The former was diagnosed in a four-year-old dachshund bitch. The patient was presented with signs of terminal chronic renal failure. Urine was bacteriologically sterile with massive amorphous crystaliuria. Bilateral nephroiithiasis was diagnosed at necropsy. The kidneys were shrunken with marked atrophy of the renal cortex and medulla. infrared spectrometry revealed that the stones comprised 100 per cent xanthine. Later, two of the patient's siblings were examined for urine xanthine content; both showed higher concentrations of xanthine than a control dog. The described case is compared with seven known published cases of Congenital xanthinuria.     

Bilateral mandibular dentigerous cysts in a dog

Cysts in the dental cavities of dogs are rare. This report documents the case of a young boxer that was referred after having had treatment for bilateral oral swellings. Dentigerous cysts were tentatively diagnosed. Surgery was performed to aspirate the fluid and remove the first premolars, which were positioned in the cysts. Histopathological examination of tissue collected during the surgical procedure confirmed the diagnosis.     

Bilateral renal oncocytoma in a Greyhound dog

A bilateral, locally invasive renal oncocytoma was diagnosed in a 10-year-old spayed female Greyhound dog. The diagnosis was based on positive staining of the tumor with the periodic acid-Schiff reaction prior to diastase treatment, on the immunohistochemical expression of cytoplasmic cytokeratin, and on the prominence of mitochondria in the tumor cells.     

Bilateral pigmented villonodular synovitis in a dog

Viilonoduiar synovitis is an extremely rare condition of the synovial membrane in the dog. A 10-yearoid, neutered crossbreed was presented with bilateral, progressive hindlimb lameness. Periarticuiar swelling was noted in both stifle joints. No craniocaudal instability was noted. Radiographs showed massive intra-articular soft tissue proliferation in both joints, with no bony involvement. Arthrocentesls was unsuccessful. Exploratory arthrotomy of the left stifle revealed a greatly thickened, florid, proliferative synovial membrane. An Incisional biopsy was carried out and the histopathological diagnosis was chronic active viilonodular synovitis. A radical synovectomy was carried out in the right stifle joint 10 days later. Corticosteroid treatment was initiated 10 days after the second surgery and continued for six weeks, with a continuous clinical improvement. Eighteen months after discontinuation of the steroid therapy, the owners reported no recurrence of clinical signs although a mild stiffness was still present.     

Bilateral maxillary periodontal ligament hamartoma in a dog

A 12.5-year-old dog was presented for severe periodontal disease and bilateral maxillary enlargement. Radiographs of the maxilla showedgeneralized root resorption, ankylosis, and rarefaction of bone with focal radiodense areas. Surgical tooth extraction of multiple maxillary teeth and bilateral incisional biopsies of the periodontal tissue and maxilla in the region of the maxillary fourth premolars were performed. Histopathologic examination showed features typical of fully differentiated periodontal ligament with abundant cementum/alveolar lining bone and sparce odontogenic epithelial cell rests. Histopathology in conjunction with radiographic and clinical signs suggested a diagnosis of bilateral periodontal ligament hamartoma. Examination 3-months postoperatively indicated uncomplicated healing of the extraction and biopsy sites with no resolution of the maxillary enlargement.     

Gall bladder torsion and rupture in a dog

A 6-year-old desexed female German Shepherd dog was referred to the Murdoch University Veterinary Hospital for assessment and management of acute onset vomiting, diarrhoea, polydipsia and lethargy of 2 days duration. Surgical, microbiological and histological findings were consistent with necrotising cholecystitis secondary to gall bladder torsion, resulting in gall bladder rupture and secondary non-septic bile peritonitis. A chronic peritoneopleural perforation resulting from an abdominal cavity foreign body and congenital peritoneopericardial hernia were also present. The dog made a full recovery following cholecystectomy, foreign body removal, repair of the peritoneopleural perforation and peritoneopericardial herniorrhaphy. This is the first recorded case of gall bladder torsion in the dog.     

Bilateral ectrodactyly and spinal deformation in a mixed-breed dog

A 3-year-old, female mixed-breed dog had malformations of both thoracic limbs and the vertebral column. Radiographs of the forelimbs showed bilateral development of 2 digits and aplasia of 3 carpal bones. Kyphosis, scoliosis, and deformed vertebrae were present in the thoracolumbar vertebral column.     

Diaphragmatic rupture and biliary tract damage in a dog

A 9-month-old bitch was presented with respiratory distress 7 days after a road traffic accident. Radiographs showed a severe hydrothorax and moderate ascites. The removal of bile-stained fluid by thoracentesis reduced the dyspnoea. A diaphragmatic and a hepatic duct rupture were found and repaired at laparotomy. A biliary peritonitis and pleuritis was present. A blood bilirubin of 67 μmol/1 and elevated serum enzymes were present prior to surgery. These changes were largely reversed once the leakage was stopped.