0000000000213285
AUTHOR
Javier Sánchez-gonzález
Reproducibility and accuracy in the morphometric and mechanical quantification of trabecular bone from 3Tesla magnetic resonance images
Abstract Objective We used an animal model to analyze the reproducibility and accuracy of certain biomarkers of bone image quality in comparison to a gold standard of computed microtomography (μCT). Materials and methods We used magnetic resonance (MR) imaging and μCT to study the metaphyses of 5 sheep tibiae. The MR images (3 T) were acquired with a T1-weighted gradient echo sequence and an isotropic spatial resolution of 180 μm. The μCT images were acquired using a scanner with a spatial resolution of 7.5 μm isotropic voxels. In the preparation of the images, we applied equalization, interpolation, and thresholding algorithms. In the quantitative analysis, we calculated the percentage of …
Non invasive blood flow measurement in cerebellum detects minimal hepatic encephalopathy earlier than psychometric tests
AIM: To assess whether non invasive blood flow measurement by arterial spin labeling in several brain regions detects minimal hepatic encephalopathy. METHODS: Blood flow (BF) was analyzed by arterial spin labeling (ASL) in different brain areas of 14 controls, 24 cirrhotic patients without and 16 cirrhotic patients with minimal hepatic encephalopathy (MHE). Images were collected using a 3 Tesla MR scanner (Achieva 3T-TX, Philips, Netherlands). Pulsed ASL was performed. Patients showing MHE were detected using the battery Psychometric Hepatic Encephalopathy Score (PHES) consisting of five tests. Different cognitive and motor functions were also assessed: alterations in selective attention we…
Reproducibilidad y exactitud en la cuantificación morfométrica y mecánica del hueso trabecular a partir de imágenes de resonancia magnética de Tesla
Resumen Objetivo En este trabajo se analizan en un modelo animal la reproducibilidad y la exactitud de ciertos biomarcadores de imagen de calidad osea utilizando como patron de referencia la microtomografia computarizada (μTC). Material y metodos Se estudiaron con RM y μTC 5 metafisis tibiales de oveja. Las imagenes de RM (3 Tesla) se adquirieron con una secuencia eco de gradiente potenciada en T1 y una resolucion espacial isotropica de 180 μm. Las imagenes de μTC se adquirieron en un escaner con una resolucion espacial de 7,5 μm en voxeles isotropicos. En la preparacion de las imagenes se aplicaron algoritmos de ecualizacion, interpolacion y umbralizacion. En el analisis cuantitativo se ca…