ASSESSMENT OF SENTINEL LYMPH NODE METASTASIS IN CANINE MAMMARY GLAND TUMORS USING COMPUTED TOMOGRAPHIC INDIRECT LYMPHOGRAPHY.

In the staging process of the breast cancer, demonstrating metastasis of the sentinel lymph node (SLN) has an important prognostic value, in both humans and animals. The aim of this prospective case-control study was to determine the diagnostic value of computed tomographic indirect lymphography (CT-LG) for detecting SLN metastasis in dogs with mammary cancer. Thirty-three female dogs with tumors in the abdominal and inguinal mammary glands were prospectively selected and subjected to CT-LG, 1 and 5 min after injection of 1 ml of contrast agent (iopamidol) in the subareolar tissue of the neoplastic and the contralateral normal mammary glands. The pattern of postcontrast opacification, degree of postcontrast enhancement, and size and shape were assessed in 65 SLNs in total and were correlated with histopathological findings. The absence of opacification or heterogeneous opacification 1 min after contrast medium injection showed the highest sensitivity, specificity, and accuracy (93%, 100%, and 98.4%, respectively). In images taken 1 min after injection, an absolute density value lower than 444 Hounsfield units (HU) in the center of the SLN also provided significant sensitivity and specificity (93.8% and 75%, respectively). The size and shape of the SLN (maximum and minimum diameter, maximum/minimum diameter ratio, maximum diameter/height of fifth thoracic vertebral body ratio) showed the lowest sensitivity and specificity. Results of this study support the hypothesis that CT-LG could help in the assessment of SLN metastasis in cases of mammary gland tumors in dogs.

Radiographic and ultrasonographic findings of uterine neoplasms in nine dogs.

The records of nine female intact dogs with histologically confirmed uterine tumors were reviewed retrospectively, and the related radiographic and ultrasonographic signs of the lesions detected were recorded. Radiography revealed a soft-tissue opacity between the urinary bladder and colon in six of seven dogs with uterine body and/or cervical tumors, and a soft-tissue opacity in the midventral abdomen in two dogs with uterine horn tumors. Ultrasonography revealed masses in all dogs with uterine body/cervical tumors and could delineate the origin of the mass in one of two dogs with uterine horn tumors. The mass was characterized ultrasonographically as solid in three dogs (all leiomyomas), solid with cystic component in four dogs (two adenocarcinomas, one leiomyoma, and one fibroleiomyoma), and cystic in two (both leiomyomas). Hyperechoic foci in the mass were observed in three dogs. Ultrasonography was a useful method for demonstrating uterine body and/or cervical tumors. However, it was not possible to ascertain sonographically that a mass originated in a uterine horn unless there was associated evidence of uterine horn to which the mass could be traced. The ultrasonographic appearance of uterine tumors was variable, and the type of neoplasm could only be determined by taking biopsies of the mass.

Effect of two sedative protocols and hepatosplenic disease on Doppler indices of splenic arteries in dogs: a preliminary study.

Doppler flow indices (DFIs), such as the resistive index (RI) and the pulsatility index (PI), are commonly used to characterize blood flow. Parenchymal infiltration of an organ and administration of sedative and anaesthetic drugs can affect DFIs by altering resistance to blood flow. In this prospective study, the effect on DFIs of two sedative protocols (acepromazine or dexmedetomidine, each combined with butorphanol) and the presence or absence of hepatic and/or splenic disease, was investigated in the splenic arteries of 75 dogs. The RI and PI in splenic arteries of dogs sedated with dexmedetomidine and butorphanol were lower than those of dogs sedated with acepromazine and butorphanol. PI in splenic arteries was higher in animals with hepatosplenic disease than in healthy animals. Receiver Operating Characteristic (ROC) curves suggested that PI measured in canine splenic arteries could be useful in predicting the presence of hepatosplenic disease in the absence of other abdominal disease.

MRI findings, surgical treatment and follow-up of a myelomeningocele with tethered spinal cord syndrome in a cat.

A 7-month-old male neutered cat was referred for paraparesis and painful sensation at the level of T13 vertebra where a dermal cyst was observed. Spine radiographs and magnetic resonance imaging (MRI) showed a well-encapsulated cyst communicating with the meninges and spinal cord, suggestive of hydromyelia and myelodysplasia. Dorsal laminectomy was performed and the cyst was completely removed. The day after surgery, the cat was ambulatory paraparetic. Involuntary defecation was observed for only a few days. The surgical specimen was cystic and covered by skin. Microscopic examination revealed a hollow hemispheric mass of glial fibrillary acidic protein (GFAP)-positive neural tissue lined by ependyma and formed of glia and vascular structures consistent with myelomeningocele (MMC). Only anecdotal descriptions of MMC have been published in the veterinary literature, mainly in the lumbosacral spinal cord. To the authors' knowledge, this is the first report of a MMC with tethered spinal cord syndrome in a cat successfully treated surgically.

Thiamine deficiency in a cat: resolution of MRI abnormalities following thiamine supplementation.

Thiamine (vitamin B(1)) is an essential component of a number of metabolic pathways and thiamine deficiency results in a progressive encephalopathy in both humans and animals. Confirming thiamine deficiency is problematic and relies on demonstrating reduced red blood cells transketolase activity, or indirect methods including urinary organic acid analysis and dietary analysis. The characteristic and selective vulnerability of different brain regions in carnivores has been demonstrated by magnetic resonance (MR) imaging in the dog and cat as an aid to diagnosis. A 2-year-old, female, domestic shorthair cat was presented with an acute onset of seizures and ataxia. MR imaging was consistent with thiamine deficiency and supplementation resulted in a progressive clinical improvement. Repeated MR imaging 4 days after starting thiamine supplementation revealed near complete resolution of the MR abnormalities. Repeated MR imaging following appropriate therapy may be useful to further confirm thiamine deficiency.

Computed tomography and radiographic indirect lymphography for visualization of mammary lymphatic vessels and the sentinel lymph node in normal cats.

The potential of computed tomography indirect lymphography (CT-indirect lymphography) and radiographic indirect lymphography to demonstrate the draining lymphatic vessels and sentinel lymph node of normal mammary glands was tested in 31 healthy female cats. The lymphatic drainage of each mammary gland was studied initially by CT-indirect lymphography after intramammary injection of 0.5 ml of iopamidol, followed by images acquired at 1, 5, 15, and 30 min after injection. One day after CT-indirect lymphography, the lymph drainage of the mammary gland was assessed using radiographic in direct lymphography af terintramammary injection of 0.5 ml of ethiodized oil followed by radiographs made at 1, 5, 15, 30, 45, and 60 min after injection. The time between intramammary injection and opacification of the draining mammary lymphatic vessels and the sentinel lymph node, the duration of adequate opacification of the draining mammary lymphatic vessels and of the sentinel lymph node and also the number and course of draining mammary lymphatic vessels and location of sentinel lymph node were compared for CT-indirect lymphography vs. radiographic indirect lymphography in each examined gland. This results suggest that radiographic indirect lymphography is easy to perform and can be used for accurate demonstration of the draining lymphatic pathways of mammary glands in radiographs made at 5-30 min after injection. However, CT-indirect lymphography was able to better demonstrate small lymphatic vessels and accurately define the exact topography of the sentinel lymph node in images acquired at 1 min after injection.

Color Doppler ultrasonography in prediction of the reducibility of intussuscepted bowel in 15 young dogs.

Color Doppler ultrasonography was performed in 15 young dogs with intestinal intussusception to test the hypothesis that color Doppler findings can be used as a predictor of the manual reducibility of the intussusception at celiotomy. Color flow Doppler ultrasonography indicated blood flow within mesentery of the intussuscepted bowel in 12 of 15 dogs and reduction was achieved in nine of these 12 dogs (75%). In the remaining three dogs and in three dogs where no color Doppler signal were observed, an irreducible intussusception was confirmed at celiotomy. Color Doppler ultrasonography is a useful method for predicting the reducibility of intussusception in dogs.

Ultrasonographic signs of intestinal intussusception associated with acute enteritis or gastroenteritis in 19 young dogs.

The ultrasonographic pattern of intestinal intussusception was studied in 19 young dogs with acute enteritis or gastroenteritis. The intussusception was observed to be a target-like mass consisting of a hyperechoic or anechoic center surrounded by multiple hyperechoic and hypoechoic concentric rings in transverse sections. In longitudinal sections, the intussusception appeared as multiple hyperechoic and hypoechoic parallel lines, as a tumor-like or pseudokidney mass, and as a trident-like configuration. Ultrasonography may provide a sensitive, specific, and accurate method of diagnosing intestinal intussusception in young dogs.