Please use this identifier to cite or link to this item:
Title: Effects of Orientation and Anisometry of Magnetic Resonance Imaging Acquisitions on Diffusion Tensor Imaging and Structural Connectomes
Author: Tudela Fernández, Raúl
Muñoz-Moreno, Emma
López-Gil, Xavier
Soria, Guadalupe
Keywords: Anisotropia
Sistema nerviós central
Ressonància magnètica
Rates (Animals de laboratori)
Central nervous system
Magnetic resonance
Rats as laboratory animals
Issue Date: 24-Jan-2017
Publisher: Public Library of Science (PLoS)
Abstract: Diffusion-weighted imaging (DWI) quantifies water molecule diffusion within tissues and is becoming an increasingly used technique. However, it is very challenging as correct quantification depends on many different factors, ranging from acquisition parameters to a long pipeline of image processing. In this work, we investigated the influence of voxel geometry on diffusion analysis, comparing different acquisition orientations as well as isometric and anisometric voxels. Diffusion-weighted images of one rat brain were acquired with four different voxel geometries (one isometric and three anisometric in different directions) and three different encoding orientations (coronal, axial and sagittal). Diffusion tensor scalar measurements, tractography and the brain structural connectome were analyzed for each of the 12 acquisitions. The acquisition direction with respect to the main magnetic field orientation affected the diffusion results. When the acquisition slice-encoding direction was not aligned with the main magnetic field, there were more artifacts and a lower signal-to-noise ratio that led to less anisotropic tensors (lower fractional anisotropic values), producing poorer quality results. The use of anisometric voxels generated statistically significant differences in the values of diffusion metrics in specific regions. It also elicited differences in tract reconstruction and in different graph metric values describing the brain networks. Our results highlight the importance of taking into account the geometric aspects of acquisitions, especially when comparing diffusion data acquired using different geometries.
Note: Reproducció del document publicat a:
It is part of: PLoS One, 2017, vol. 12, num. 1, p. e0170703
Related resource:
ISSN: 1932-6203
Appears in Collections:Articles publicats en revistes (Cirurgia i Especialitats Medicoquirúrgiques)

Files in This Item:
File Description SizeFormat 
667032.pdf5.44 MBAdobe PDFView/Open

This item is licensed under a Creative Commons License Creative Commons