Artículos de revistas
Error bounds in diffusion tensor estimation using multiple-coil acquisition systems
Fecha
2013-06Registro en:
Beltrachini, Leandro; Von Ellenrieder, Nicolás; Muravchik, Carlos Horacio; Error bounds in diffusion tensor estimation using multiple-coil acquisition systems; Elsevier Science Inc; Magnetic Resonance Imaging; 31; 8; 6-2013; 1372-1383
0730-725X
CONICET Digital
CONICET
Autor
Beltrachini, Leandro
Von Ellenrieder, Nicolás
Muravchik, Carlos Horacio
Resumen
We extend the diffusion tensor (DT) signal model for multiple-coil acquisition systems. Considering the sum-of-squares reconstruction method, we compute the Cramér–Rao bound (CRB) assuming the widely accepted noncentral chi distribution. Within this framework, we assess the effect of noise in DT estimation and other measures derived from it, as a function of the number of acquisition coils, as well as other system parameters. We show the applications of CRB in many actual problems related to DT estimation: we compare different gradient field setup schemes proposed in the literature and show how the CRB can be used to choose a convenient one; we show that for fiber-type anisotropy tensors the ellipsoidal area ratio (EAR) can be estimated with less error than other scalar factors such as the fractional anisotropy (FA) or the relative anisotropy (RA), and that for this type of anisotropy tensors, increasing the number of coils is equivalent to increasing the signal-to-noise ratio, i.e., the information of the different coils can be regarded as independent. Also, we present results showing the CRB of several parameters for actual DT-MRI data. We conclude that the CRB is a valuable tool to optimal experiment design in DT-related studies.