ULTRASONOGRAPHIC DETECTION OF ADRENAL GLAND TUMOR AND URETEROLITHIASIS IN A GUINEA PIG

A 5-year-old guinea pig was presented to the University of Berne Small Animal Radiology Department for an ultrasound examination of the abdomen to confirm a suspected diagnosis of Cushing's syndrome. The patient had bilateral alopecia, was apathic and obese. Ultrasonographically, a tumor of the left adrenal gland, obstruction of the left ureter by an ureterolith, as well as hydronephrosis of the left kidney were detected. During surgery to relieve the ureteral obstruction the adrenal gland tumor was removed. The guinea pig died post-operatively due to blood loss. The left adrenal gland tumor was found histopathologically to be an adenoma and the right adrenal gland also had multiple small adenomas, but grossly appeared normal. The ureterolith was analyzed and found by x-ray diffraction to consist of calcium carbonate.     

TRANSTHORACIC LUNG ULTRASOUND IN NORMAL DOGS AND DOGS WITH CARDIOGENIC PULMONARY EDEMA: A PILOT STUDY

Pulmonary edema is the most common complication of left‐sided heart failure in dogs and early detection is important for effective clinical management. In people, pulmonary edema is commonly diagnosed based on transthoracic ultrasonography and detection of B line artifacts (vertical, narrow‐based, well‐defined hyperechoic rays arising from the pleural surface). The purpose of this study was to determine whether B line artifacts could also be useful diagnostic predictors for cardiogenic pulmonary edema in dogs. Thirty‐one normal dogs and nine dogs with cardiogenic pulmonary edema were prospectively recruited. For each dog, presence or absence of cardiogenic pulmonary edema was based on physical examination, heartworm testing, thoracic radiographs, and echocardiography. A single observer performed transthoracic ultrasonography in all dogs and recorded video clips and still images for each of four quadrants in each hemithorax. Distribution, sonographic characteristics, and number of B lines per thoracic quadrant were determined and compared between groups. B lines were detected in 31% of normal dogs (mean 0.9 ± 0.3 SD per dog) and 100% of dogs with cardiogenic pulmonary edema (mean 6.2 ± 3.8 SD per dog). Artifacts were more numerous and widely distributed in dogs with congestive heart failure (P < 0.0001). In severe cases, B lines increased in number and became confluent. The locations of B line artifacts appeared consistent with locations of edema on radiographs. Findings from the current study supported the use of thoracic ultrasonography and detection of B lines as techniques for diagnosing cardiogenic pulmonary edema in dogs.     

ENDOSCOPIC ULTRASOUND INSTRUMENTATION, APPLICATIONS IN HUMANS, AND POTENTIAL VETERINARY APPLICATIONS

Endoluminal scanning under endoscopic guidance, or endoscopic ultrasonography (EUS), has become the most significant advance for imaging the gastrointestinal (GI) tract wall and contiguous organs in the past 20 years. It was originally designed to overcome the limitations in humans to imaging the abdominal organs transabdominally, such as large penetration depths and GI air. This imaging modality provides detailed images of pathological processes both within and outside of the GI wall since a high-frequency transducer can be brought into close proximity with the target regions. It has found most success in humans for the staging of lung, gastric, and esophageal cancer, the detection of both lymphatic and hepatic metastases, and diagnosis of pancreatitis and pancreatic cancer, as well as achieving an important role in interventional and therapeutic procedures. The EUS examination can be performed to examine both the thorax and abdomen in animals when both conventional transthoracic or transabdominal ultrasound are inadequate due to intervening air, bone, large penetration depths, or obesity. The echoendoscope is similar to a conventional endoscope but has an ultrasound transducer at its tip. Both radial and linear multifrequency scanners are available. Linear scanners allow fine-needle aspiration (FNA) of the bowel wall or extraluminal structures. Transducer coupling is either by direct mucosal contact or by inflation of a water-filled balloon surrounding the transducer. Current thoracic applications for EUS in veterinary medicine include examination of the mediastinum, bronchial lymph nodes, esophagus, and pulmonary lesions as well as FNA of pulmonary masses. Abdominal applications include examination of both pancreatic limbs and the liver, including portosystemic shunts, detection of lymphadenomegaly, and examination of the gastric wall, duodenum, and jejunum. Other potential applications in dogs and cats include tumor staging and intrapelvic ultrasound.     

DOPPLER MEASUREMENT OF SPLANCHNIC BLOOD FLOW DURING DIGESTION IN UNSEDATED NORMAL DOGS

The purpose of this study was to measure splanchnic blood flow during digestion in unsedated dogs by using duplex Doppler sonography. The study population consisted of 12 healthy dogs. Blood flow in the cranial mesenteric artery, the celiac artery, and the aorta was measured before a test meal and at 20, 60, and 90 minutes after eating. The following measurements were made or calculated: vessel diameter, peak systolic velocity, end diastolic velocity, mean velocity, resistive index, pulsatility index, and flow volume. There was a significant postprandial decrease in the resistive and pulsatility indices in both the cranial mesenteric (preprandial RI = 0.867, postprandial RI = 0.796, preprandial PI = 3.033, postprandial PI = 2.173) and the celiac (preprandial RI = 0.854, postprandial RI = 0.769, preprandial PI = 2.639, postprandial PI = 1.930) arteries. In both vessels the end diastolic velocity, the mean velocity, and the flow volume increased significantly postprandially. These changes occurred significantly earlier in the celiac artery than in the cranial mesenteric artery. The findings most likely correspond to postprandial splanchnic vasodilation. Doppler ultrasound provide a good methode of detecting changes in postprandial splanchnic blood flow in the dog.     

INTRAVERTEBRAL DISC HERNIATION (SCHMORL'S NODE) IN FIVE DOGS

The herniation of intervertebral disc material into the vertebral body, known as Schmorl's nodes, is a well described disease process in man. Schmorl's nodes have not until now been described in the dog. This paper describes intravertebral disc herniation in the dog based on five patients taken from a retrospective study of dogs suspected of having cauda equina syndrome. The significance of intravertebral disc herniation in the dog at this time is that they indicate a disturbance in the vertebral endplate, they present definite radiographic signs, should be considered in patients with ostecohondrosis, and remain a possibls etiology for fibrocartilaginous emboli. Back pain is a common sign in people when Schmorl's nodes were the only pathologic findings. The common signs of palpatory pain in the lumbosacral region of the dogs in this report is noted but cannot be directly correlated at this time to the intravertebral disc herniation; however, it is suspected in two of the cases.     

Cardiomyopathy in Dystrophin-Deficient Hypertrophic Feline Muscular Dystrophy

A colony of cats affected with hypertrophic feline muscular dystrophy was used to study the occurrence of cardiomyopathy associated with dystrophin deficiency. Affected male and female cats, obligate carrier females, and unaffected healthy littermates were followed from 12 weeks of age into adulthood. Thoracic radiography, 2-D echocardiography, and 2-D-derived M-mode echocardiography were performed at 3-month intervals until 12 months of age and regularly thereafter. From 9 months of age, all affected cats had larger hearts than normal and carrier animals. Left ventricular wall thickness in systole and in diastole and interventricular septal thickness in systole were greater in affected cats 12 months and older when compared with normal or heterozygous animals (P < .05). The myocardium of affected cats was diffusely hypoechoic and thickened. Multiple hyperechoic foci were in the myocardium and papillary musculature. Shortening fraction was normal in all cats. Changes seen in carrier females included enlargement and hyperechogenicity of the papillary musculature after the age of 2 years. Gross and light microscopic examination revealed left ventricular wall thickening with multiple foci of mineralization in 2 of 5 hearts from dystrophin-deficient cats. Although approximately 10% of the normal dystrophin amount was present in the skeletal muscle, dystrophin could not be detected in the myocardium. Early onset concentric myocardial hypertrophy was present in all adult cats. Lesions were mainly localized in the myocardium of the left ventricular free wall and interventricular septum, papillary musculature, and the endocardium. Clinical signs of heart failure developed only infrequently in cats with hypertrophic feline muscular dystrophy.