Lorena Adão Vescovi Séllos Costa

Bone demineralization in the lumbar spine of dogs submitted to prednisone therapy

Glucocorticoids are drugs widely used in veterinary medicine; however, besides their clinical benefits, their use can trigger undesirable effects. A clinical trial was performed on eight healthy dogs with the intent of evaluating possible alterations in the bone mineral density after therapy with prednisone using a helical computed tomography. All animals received prednisone orally at a dose of 2 mg/kg of weight for 30 days. The bone mineral density was determined by obtaining the vertebral body radiodensity of the second lumbar vertebra values immediately before and after the administration of the medication. The experimental protocol allowed for the characterization of a significant (P < 0.01) reduction of the vertebral body radiodensity of the second lumbar vertebra. At the end of the experiment, it was characterized by a loss of bone mass of approximately 14%. None of the animals presented pathologic fracture at the end of the administration of the medication. This study verified that the alterations in the bone metabolism of the dogs submitted to the therapy with prednisone in a dosage of 2 mg/kg occur rapidly, which recommends a monitoring of the patients for the prevention of pathologic fractures.

Radiodensidade hepática de cães hígidos por tomografia computadorizada helicoidal

The objectives of the study reported here were to obtain medium values of hepatic parenchyma radiodensity in healthy dogs, and also describe the adaptation in canine specie of a tomographic density measurement technique, which has already been used in humans. For the accomplishment of this study tomographic exams were realized in eight young dogs without sex or breed definition. After the exams, the livers degree of HU attenuation was determined through a mean value of three selected regions of interest (ROI) in hepatic parenchyma obtained in three different levels of cut. Additionally, a region of interest in the splenic parenchyma was analyzed in three different levels of cut for comparative evaluation between the organs. In the experimental group it was observed an X-ray attenuation mean value of 59.58±3.34 Hounsfield Units (HU). The density difference between hepatic and splenic parenchyma was a mean value of 4.69±7.77HU. In the present study, it was observed that computed tomography is a technique with high sensitivity to estimate hepatic parenchyma density. The establishment of reference values and the standardizing of an evaluation methodology allow a better characterization of radiodensity changes in the tomographic exams, assisting in establishing a diagnosis and minimizing the necessity of invasive testing to the patient.

Radiografia quantitativa hepática de cães tranquilizados com acepromazina

The acepromazine is one of the most commonly tranquilizer used in veterinary medicine and its use may cause splenomegaly. However it is not known if it can cause hepatomegaly. The aim of this study is to evaluate the quantitative radiography with digital assistance to determine the liver size and volume of dogs tranquilized with acepromazine. Nine healthy dogs were radiographed in the lateral right and ventral-dorsal liver , before and after intramuscular administration of acepromazine at a dose of 0.1kg-1. It was possible to characterize the size and increase in liver size (P<0.05) between the different experimental moments with a strong positive correlation between the measures liver assets. The quantitative radiographic technique used in this study accurately characterized the increase in size and volume of the liver in dogs treated with acepromazine.

QUANTITATIVE COMPUTED TOMOGRAPHY OF THE LIVER IN JUVENILE GREEN SEA TURTLES (CHELONIA MYDAS)

Abstract:  Quantitative computed tomography (QCT) is a highly sensitive, applicable technique for determining the x-ray attenuation of organs. This technique reveals great precision in the detection of alterations in the x-ray attenuation of hepatic parenchyma, although the lack of studies establishing normal values limits its application in wild animals. The objective of this study was to establish mean hepatic attenuation values in four healthy juvenile sea turtles (Chelonia mydas) using QCT. Helical computed tomography scans were performed and regions of interest selected in the liver after multi-planar reconstruction images were obtained. The mean attenuation value for the hepatic parenchyma in these four turtles was 60.09 ± 5.3 standard deviation Hounsfield units. Determining normal x-ray attenuation values of the liver increases knowledge of the computed tomographic anatomy of this species and may be useful in the investigation of hepatic diseases.

Computed tomography in the diagnosis of steroidal hepatopathy in a dog: case report

Relata-se o caso de um cao da raca Yorkshire, de oito anos de idade, com historico de tratamento com prednisona na dose de 1mg/kg de peso, a cada 24 horas, por dois anos. A tomografia computadorizada helicoidal revelou hepatomegalia associada a hiperatenuacao, com radiodensidade de 82,55 unidades Hounsfield (HU). O baco apresentava radiodensidade media de 57,17HU, sendo observada diferenca de radiodensidade de 25,38HU entre os dois orgaos. Por meio do historico e dos achados da tecnica de imagem, foi possivel determinar o diagnostico presuntivo de hepatopatia esteroidal compativel com acumulo de glicogenio hepatico. Concluiu-se que a tomografia computadorizada possibilitou caracterizar a lesao hepatica e presumir o diagnostico de hepatopatia esteroidal

Quantitative computed tomography of the liver in dogs submitted to prednisone therapy

The aim of this study is to evaluate the possible alterations in radiodensity of the hepatic parenchyma and spleen resulting from the corticotherapy with prednisone, correlating these findings with serum biochemical hepatic transaminase activity. A clinical trial was performed on eight healthy dogs with the intent of evaluating possible hepatic alterations after prednisone therapy using quantitative computed tomography. All animals received prednisone orally at a dose of 2mg/kg of weight for 30 days. The radiodensity of the liver and spleen was determined before and after the period that the medication was administered. An increase in the radiodensity of the hepatic parenchyma between the initial and final experimental stages was observed. In the present study the existence of early hepatic alterations were verified, which are compatible with glycogen storage.

Pulsed-wave tissue Doppler imaging of the myocardium of cats with induced thyrotoxicosis

Left ventricular myocardial motion was quantified using pulsed-wave tissue Doppler imaging (PW-TDI) in nine adult cats before and after thyrotoxicosis induction. In order to induce thyrotoxicosis, all cats were given 150µg kg-1 of levothyroxine sodium as a single oral dose each day for 10 weeks. PW-TDI examinations were performed immediately before the induction and by the end of the experimental protocol. An increase in myocardial motion velocity was documented at the interventricular septum level, demonstrated by an elevation in systolic (Sa), and early (Ea) and late (Aa) diastolic waves (P<0.05). However, no alteration in Sa, Ea and Aa values was seen at the lateral mitral annulus. Heart rate increased significantly between the experimental stages, and three of the animals presented fused Ea and Aa waves at the end of the experiment. The experimental protocol used in this study caused alterations in left ventricular myocardial motion velocity, but did not impair left ventricular diastolic function.

Grau de desmineralização em osso trabecular e cortical por meio de tomografia computadorizada quantitativa em cães submetidos à terapia com prednisona

Glucocorticoids are widely used in veterinary medicine. However, beyond the beneficial effects, their use can trigger a series of unwanted effects. A clinical trial was conducted in eight healthy dogs in order to assess possible changes in bone mineral density after therapy with prednisone using helical computed tomography. All animals received oral prednisone at a daily dose of 2mg kg-1 of body weight for 30 days. Bone mineral density was determined by the obtaining of radiodensity values from the cortical region and the trabecular region of the second lumbar vertebra immediately before and after the period of drug administration. The experimental protocol allowed the characterization of a significant (P<0.01) decrease of trabecular bone radiodensity on the second lumbar vertebra, but no significant demineralization was found in the cortical region. None of the dogs used in this experiment had pathological fracture at the end of the experimental protocol. This study showed that in dogs subjected to therapy with prednisone at a dose of 2mg kg-1 changes in bone metabolism occur early in trabecular bone, being recommended to monitor these patients for the prevention of pathologic fractures.