Comparison of Ferucarbotran-Enhanced MRI and Triple-Phase MDCT for the Detection of Hepatocellular Carcinoma in Advanced Liver Cirrhosis

PURPOSE: To compare the diagnostic performance of ferucarbotran-enhanced MRI at 1.5-T with triple-phase multidetector-row helical CT (MDCT) to detect hepatocellular carcinoma in patients with advanced liver cirrhosis. MATERIALS AND METHODS: Twenty patients with advanced liver cirrhosis (Child's class B:C = 8:12) underwent ferucarbotran-enhanced MRI and triple-phase MDCT prior to liver transplantation. The mean time interval between the two imaging techniques was 18 days (range, 1-35 days). Three radiologists independently reviewed both images on a lesion-by-lesion basis and interpreted them for comparison with the pathologic findings of the explanted livers. As well, the sensitivity and an alternative-free response receiver operating characteristics (ROC) analysis was used to evaluate the diagnostic performance of each technique. RESULTS: The mean area under the ROC curve (Az) was significantly higher for the triple-phase MDCT (0.766) compared to the ferucarbotran-enhanced MRI (0.675) (p < 0.001). Similarly, the mean sensitivity of the triple-phase MDCT (60.3%) exceeded the ferucarbotran-enhanced MRI (43.1%). The results indicate that the triple-phase MDCT provides significantly greater mean sensitivity than the ferucarbotran-enhanced MRI (p < 0.001). CONCLUSION: The triple-phase MDCT provided a better diagnostic performance and higher sensitivity than the ferucarbotran-enhanced MRI for the detection of hepatocellular carcinomas in patients with advanced liver cirrhosis.

Tracking of Neural Stem Cells in Rats with Intracerebral Hemorrhage by the Use of 3T MRI

OBJECTIVE: To access the feasibility of clinically available 3T MRI to detect the migration of labeled neural stem cells (NSCs) in intracerebral hemorrhage (ICH) in a rat model. MATERIALS AND METHODS: The ethics committee of our institution approved this study. ICH was induced by the injection of collagenase type IV into the right striatum of ten Sprague-Dawley rats. Human NSCs conjugated with Feridex (super-paramagnetic iron oxide: SPIO) were transplanted into the left striatum one week after ICH induction. MRI was performed on a 3T scanner during the first, second, third, fourth, and sixth weeks post-transplantation. MRI was obtained using coronal T2- and T2*-weighted sequences. Two rats were sacrificed every week after in vivo MRI in order to analyze the histological findings. RESULTS: ICH in the right striatum was detected by MRI one and two weeks after transplantation without migration of the NSCs. There was no migration of the NSCs as seen on the histological findings one week after transplantation. The histological findings two weeks after transplantation showed a small number of NSCs along the corpus callosum. On MRI three weeks after transplantation, there was a hypointense line along the corpus callosum and decreased signal intensity in the right periventricular region. Histological findings three weeks after transplantation confirmed the presence of the hypointense line representing SPIO-labeled NSCs. MRI four and six weeks after transplantation showed a hypointense spot in the right periventricular region. The histological findings four and six weeks after transplantation showed the presence of prominent NSCs in the right periventricular region. CONCLUSION: 3T MRI can detect the migration of NSCs in rats with ICH along the corpus callosum. Therefore, 3T MRI could be feasible for detecting the migration of NSCs in the clinical setting of stem cell therapy.

Aporte de la resonancia magnética al diagnóstico de las neoplasias hepáticas / Contribution of magnetic resonance imaging to the diagnosis of hepatic neoplasm

Presence and characterization of focal liver lesions is of fundamental importance in abdominal MR imaging. An abundance of benign and malignant lesions with various appearances can be found in MR imaging. Since both malignant and benign lesions may occur concomitantly in the same patient, it is of decisive importance not only to detect but to characterize a lesion. This is particularly mandatory if a surgical procedure or multimodal therapy concepts are planned. Intravenously administered, non-specific contrast agents have been used in abdominal MR imaging for more than fifteen years. This category of contrast agents -typically Gadolinium (Gd)- chelated compounds - has properties similar to those of extracellular space (ECS) contrast agents used in iodineenhanced CT. Various efforts have been made over the last decade to develop contrast agents that combine the excellent tissue specificity. These contrast media have been divided into two categories according to their target cell population: substances tailored to the reticuloendothelial system (RES) of the liver and compounds targeted to hepatocytes. In the following article, we will discuss the different classes of contrast agents regarding their biodistribution, pharmacokinetic properties, typical imaging features, and clinical impact

La presencia y caracterización de las lesiones hepáticas focales es de importancia fundamental en las imágenes abdominales obtenidas por resonancia magnética (RM). Es posible encontrar gran cantidad de lesiones benignas y malignas con diversa apariencia en la RM. Dado que en un mismo paciente pueden hallarse lesiones benignas y malignas concomitantemente, es de importancia decisiva no sólo la detección sino la caracterización de una lesión. Esto es especialmente imperativo cuando se planea realizar un procedimiento quirúrgico o una terapia multimodal. Los agentes de contraste no específicos, administrados por vía intravenosa, se utilizan en las imágenes abdominales obtenidas por RM desde hace más de quince años. Esta categoría de medios de contraste (típicamente, quelatos de gadolinio) tiene propiedades similares a aquellos agentes de contraste del espacio extracelular (EEC) utilizados en las tomografías computarizadas con refuerzo de contraste yodado. En la última década se realizaron varios esfuerzos para elaborar agentes de contraste que combinen una excelente resolución de contraste de las imágenes por RM con una mejoría en la especificidad tisular. Estos medios de contraste se dividieron en dos categorías de acuerdo con su población celular blanco: las sustancias dirigidas al sistema reticuloendotelial (SER) del hígado y los compuestos dirigidos a los hepatocitos. En el siguiente artículo analizamos las diferentes clases de medios de contraste con respecto a su biodistribución, propiedades farmacocinéticas, características típicas de las imágenes y consecuencias clínicas

Experimental study on biological characteristics of ferumoxides labeled neural stem cells / 重庆医科大学学报

0.05).When the concentration of ferumoxides exceeded 22.4?g/ml,there was significant difference(P