In this paper, we consider combined TV denoising and diffusion tensor fitting in DTI using the affine-invariant Riemannian metric on the space of diffusion tensors. Instead of first fitting the diffusion tensors, and then denoising them, we define a suitable TV type energy functional which incorporates the measured DWIs (using an inverse problem setup) and which measures the nearness of neighboring tensors in the manifold. To approach this functional, we propose generalized forward- backward splitting algorithms which combine an explicit and several implicit steps performed on a decomposition of the functional. We validate the performance of the derived algorithms on synthetic and real DTI data. In particular, we work on real 3D data. To our knowledge, the present paper describes the first approach to TV regularization in a combined manifold and inverse problem setup.

Download full-text PDF

Source
http://dx.doi.org/10.1109/TMI.2016.2528820DOI Listing

Publication Analysis

Top Keywords

tensor fitting
8
diffusion tensor
8
manifold approach
8
diffusion tensors
8
inverse problem
8
problem setup
8
combined tensor
4
fitting regularization
4
diffusion
4
regularization diffusion
4

Similar Publications

Early Identification of Myocardial Microstructural Alterations in Hypertrophic Cardiomyopathy with in Vivo Cardiac Diffusion-Tensor Imaging.

Radiol Cardiothorac Imaging

February 2025

From the Department of Magnetic Resonance Imaging, Radiology Imaging Center, Fuwai Hospital, National Center for Cardiovascular Diseases, State Key Laboratory of Cardiovascular Disease, Chinese Academy of Medical Sciences and Peking Union Medical College, Beilishi Road No. 167, Xicheng District, Beijing 100037, China (Z.D., Y.T., G.Y., X.M., S.Y., J.W., X.X., K.Y., M.L., X.C., S.Z.); Clinical and Technical Support, Philips Healthcare, Beijing, China (P.S.); and Paul C. Lauterbur Research Center for Biomedical Imaging, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, SZ University Town, Shenzhen, China (K.Z., Y.Z.).

Purpose To explore the diffusion characteristics of hypertrophic cardiomyopathy (HCM) using in vivo cardiac diffusion-tensor imaging (cDTI) and to determine whether cDTI could help identify abnormal myocardium beyond cardiac MRI findings of fibrosis and hypertrophy. Materials and Methods In this prospective study conducted from April to August 2023, participants with HCM and healthy volunteers were enrolled for cardiac MRI evaluation, including cine, late gadolinium enhancement (LGE), T1 mapping, and cDT imaging, using a 3.0-T scanner.

View Article and Find Full Text PDF

Repeated muscle micro-trauma may cause severe muscle damage. Diffusion tensor imaging (DTI) exhibits sensitivity to microstructural changes in skeletal muscle. We hypothesize that longer diffusion times enhance sensitivity to micro-trauma and that membrane permeability increases with micro-trauma.

View Article and Find Full Text PDF

The computation of magnetizability tensors using gauge-including atomic orbitals is discussed in the context of Cholesky decomposition (CD) for the two-electron repulsion integrals with a focus on the involved doubly differentiated integrals. Three schemes for their handling are suggested: the first exploits the density fitting (DF) aspect of Cholesky decomposition, the second uses expressions obtained by differentiating the CD expression for the unperturbed two-electron integrals, while the third addresses the issue that the first two schemes are not able to represent the doubly differentiated integrals with arbitrary accuracy. This scheme uses a separate Cholesky decomposition for the cross terms in the doubly differentiated two-electron integrals.

View Article and Find Full Text PDF

Spectroscopic Signatures of Phonon Character in Molecular Electron Spin Relaxation.

ACS Cent Sci

December 2024

Division of Chemistry and Chemical Engineering, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125, United States.

Spin-lattice relaxation constitutes a key challenge for the development of quantum technologies, as it destroys superpositions in molecular quantum bits (qubits) and magnetic memory in single molecule magnets (SMMs). Gaining mechanistic insight into the spin relaxation process has proven challenging owing to a lack of spectroscopic observables and contradictions among theoretical models. Here, we use pulse electron paramagnetic resonance (EPR) to profile changes in spin relaxation rates ( ) as a function of both temperature and magnetic field orientation, forming a two-dimensional data matrix.

View Article and Find Full Text PDF

Purpose: To complement the current research on altered white matter integrity in children with non-lesional temporal lobe epilepsy (NL-TLE), especially the correlation between diffusion metrics and clinical characteristics, so as to provide imaging evidence for clinical practice.

Methods: Children with temporal lobe epilepsy and no lesions on magnetic resonance imaging (MRI) were retrospectively collected from 2016.01.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!