RESUMEN
The aim of this study was to adapt the human magnetic resonance imaging (MRI) sequences for use in the routine examination of canine mammary glands. MRI was performed on 10, middle- to old-aged dogs of different breeds. It was found that T1- and T2-weighted spin echo, short T1 inversion recovery sequences and a gradient echo (GE) dynamic T1-weighted measurement made in the coronal and transversal planes were the most informative MR diagnostic methods for imaging canine mammary tumours. The static MR technique is the most detailed imaging modality for differentiating the tissue types in the substance of the mammary gland. The MRI findings were in close relationship with the histological result (five malignant mixed tumours and five cases of invasive ductal carcinoma). Using the GE dynamic contrast-enhanced sequence the morphological patterns as well as the kinetic parameters proved to be malignant. By the dynamic measurement technique initial information was obtained on the contrast enhancing properties, which are valuable factors during in vivo staging and in the prognostic work.
Asunto(s)
Carcinoma Ductal de Mama/veterinaria , Enfermedades de los Perros/patología , Imagen por Resonancia Magnética/veterinaria , Neoplasias Mamarias Animales/patología , Tumor Mixto Maligno/veterinaria , Animales , Carcinoma Ductal de Mama/irrigación sanguínea , Carcinoma Ductal de Mama/patología , Perros , Femenino , Imagen por Resonancia Magnética/métodos , Neoplasias Mamarias Animales/irrigación sanguínea , Tumor Mixto Maligno/irrigación sanguínea , Tumor Mixto Maligno/patología , Neovascularización Patológica/patología , Neovascularización Patológica/veterinariaRESUMEN
Whether cardiopulmonary bypass alone or together with the manipulation of the aorta produce neurological complication remains controversial. Using a domestic pig model of cardiopulmonary bypass, we investigated the immediate effects of aortic cannulation and cardiopulmonary bypass on neuronal injury in different brain regions. We compared the presence of neuronal injury in three experimental groups: non-operated controls (n = 3); operated controls with aortic cannulation without cardiopulmonary bypass (n = 5); operated animals undergoing cardiopulmonary bypass (n = 5). Pyknotic cells were counted in the prefrontal cortex, cerebellum and in the hippocampal formation. Calretinin immunohistochemistry was used to show possible ischemic damages in the hippocampus which is known to be one of the most sensitive brain regions to ischemia. Decreased calretinin immunoreaction and reduced number of calretinin-positive neurons were observed in the hippocampal dentate gyrus following aortic cannulation or cardiopulmonary bypass compared to the non-operated control group. Changes were more severe following cardiopulmonary bypass than after cannulation of the aorta alone. The frequency of pyknotic cell nuclei was not different in the control and experimental groups. Our experimental study suggests that both cannulation of the aorta alone and cardiopulmonary bypass affect a selected population of neurons.
Asunto(s)
Aorta , Encéfalo/patología , Puente Cardiopulmonar/efectos adversos , Cateterismo/efectos adversos , Animales , PorcinosRESUMEN
Magnetic resonance imaging (MRI) was tested for evaluation of the soft tissue structures of the equine digit in 16 limbs, derived from three adult warmblood horses and two newborn warmblood foals. The following measuring sequences were used in sagittal, transversal and coronal planes: spin echo, gradient echo, inversion recovery. The images were made with a 1.5 Tesla Siemens scanner in a CP-Helmholtz circular coil. To compare the visualization of the same tissue structures in adult and in newborn cases the limbs were imaged with the routinely used MRI sequences that are used for mature tissues. In newborn foals the bursa podotrochlearis could not be determined with the used sequences. For both the adult and newborn limbs the most visualization of the same tissue structures including the fluid spaces and growth plates were taken by the inversion recovery sequence. T2 sequence was very informative in adult cases but moderately in newborn foals.