Purpose: Electron paramagnetic resonance imaging has surfaced as a promising noninvasive imaging modality that is capable of imaging tissue oxygenation. Due to extremely short spin-spin relaxation times, electron paramagnetic resonance imaging benefits from single-point imaging and inherently suffers from limited spatial and temporal resolution, preventing localization of small hypoxic tissues and differentiation of hypoxia dynamics, making accelerated imaging a crucial issue.
Methods: In this study, methods for accelerated single-point imaging were developed by combining a bilateral k-space extrapolation technique with model-based reconstruction that benefits from dense sampling in the parameter domain (measurement of the T2 (*) decay of a free induction delay). In bilateral kspace extrapolation, more k-space samples are obtained in a sparsely sampled region by bilaterally extrapolating data from temporally neighboring k-spaces. To improve the accuracy of T2 (*) estimation, a principal component analysis-based method was implemented.
Results: In a computer simulation and a phantom experiment, the proposed methods showed its capability for reliable T2 (*) estimation with high acceleration (8-fold, 15-fold, and 30-fold accelerations for 61×61×61, 95×95×95, and 127×127×127 matrix, respectively).
Conclusion: By applying bilateral k-space extrapolation and model-based reconstruction, improved scan times with higher spatial resolution can be achieved in the current single-point electron paramagnetic resonance imaging modality.
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http://dx.doi.org/10.1002/mrm.25282 | DOI Listing |
Oral Oncol
January 2025
Department of Oral and Maxillofacial Surgery, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, Guangdong, China; Guangdong Province Key Laboratory of Stomatology, Guangzhou, Guangdong, China. Electronic address:
Background: Cervical lymph node metastasis (LNM) is a well-established poor prognosticator of oral squamous cell carcinoma (OSCC), in which occult metastasis is a subtype that makes prediction challenging. Here, we developed and validated a deep learning (DL) model using magnetic resonance imaging (MRI) for the identification of LNM in OSCC patients.
Methods: This retrospective diagnostic study developed a three-stage DL model by 45,664 preoperative MRI images from 723 patients in 10 Chinese hospitals between January 2015 and October 2020.
Eur Radiol Exp
January 2025
Unit of Medical Physics, Pisa University Hospital "Azienda Ospedaliero-Universitaria Pisana", Pisa, Italy.
Background: Photon-counting detector (PCD) technology has the potential to reduce noise in computed tomography (CT). This study aimed to carry out a voxelwise noise characterization for a clinical PCD-CT scanner with a model-based iterative reconstruction algorithm (QIR).
Methods: Forty repeated axial acquisitions (tube voltage 120 kV, tube load 200 mAs, slice thickness 0.
J Natl Cancer Cent
December 2024
Department of Urology, Fudan University Shanghai Cancer Center, Shanghai, China.
Background: Completely endophytic renal tumors (CERT) pose significant challenges due to their anatomical complexity and loss of visual clues about tumor location. A facile scoring model based on three-dimensional (3D) reconstructed images will assist in better assessing tumor location and vascular variations.
Methods: In this retrospective study, 80 patients diagnosed with CERT were included.
Comput Methods Programs Biomed
December 2024
Department of Information and Communication Engineering, North University of China, Taiyuan 030051, China; The State Key Lab for Electronic Testing Technology, North University of China, Taiyuan 030051, China. Electronic address:
Background And Objective: Sparse-view computed tomography (CT) speeds up scanning and reduces radiation exposure in medical diagnosis. However, when the projection views are severely under-sampled, deep learning-based reconstruction methods often suffer from over-smoothing of the reconstructed images due to the lack of high-frequency information. To address this issue, we introduce frequency domain information into the popular projection-image domain reconstruction, proposing a Tri-Domain sparse-view CT reconstruction model based on Sparse Transformer (TD-STrans).
View Article and Find Full Text PDFNeural Netw
December 2024
Department of Physics, University of Trento, Via Sommarive 14, Trento, 38123, TN, Italy.
In this study, we address the challenge of analyzing electrophysiological measurements in neuronal networks. Our computational model, based on the Reservoir Computing Network (RCN) architecture, deciphers spatio-temporal data obtained from electrophysiological measurements of neuronal cultures. By reconstructing the network structure on a macroscopic scale, we reveal the connectivity between neuronal units.
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