scholarly journals Total Generalized Variation Method for Deconvolution-based CT Brain Perfusion

2019 ◽  
Author(s):  
Дмитрий Люков ◽  
Dmitry Lyukov ◽  
Андрей Крылов ◽  
Andrey Krylov ◽  
Василий Лукшин ◽  
...  
Keyword(s):  
Synthetic Data ◽  
Blood Perfusion ◽  
Brain Perfusion ◽  
Variation Method ◽  
Total Generalized Variation ◽  
Perfusion Computed Tomography ◽  
Singular Value Decomposition Method ◽  
Ct Brain ◽  
Generalized Variation ◽  
Value Decomposition

Deconvolution-based method for image analysis of cerebral blood perfusion computed tomography has been suggested. This analysis is the important part of diagnostics of ischemic stroke. The method is based on total generalized variation regularization algorithm. The algorithm was tested with generated synthetic data and clinical data. Proposed algorithm was compared with singular value decomposition method using Tikhonov regularization and with total variation based deconvolution method. It was shown that the suggested algorithm gives better results than these methods. The proposed algorithm combines both deconvolution and denoising processes, so results are more noisy resistant. It can allow to use lower radiation dose.

scholarly journals Cerebral Extracellular Lactate Increase is Predominantly Nonischemic in Patients with Severe Traumatic Brain Injury

2013 ◽  
Vol 33 (11) ◽  
pp. 1815-1822 ◽  
Author(s):  
Nathalie Sala ◽  
Tamarah Suys ◽  
Jean-Baptiste Zerlauth ◽  
Pierre Bouzat ◽  
Mahmoud Messerer ◽  
...  
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Severe Traumatic Brain Injury ◽  
Brain Perfusion ◽  
Cerebral Microdialysis ◽  
Lactate Metabolism ◽  
Perfusion Computed Tomography ◽  
Extracellular Lactate ◽  
Ct Brain ◽  
Brain Lactate

Growing evidence suggests that endogenous lactate is an important substrate for neurons. This study aimed to examine cerebral lactate metabolism and its relationship with brain perfusion in patients with severe traumatic brain injury (TBI). A prospective cohort of 24 patients with severe TBI monitored with cerebral microdialysis (CMD) and brain tissue oxygen tension (PbtO2) was studied. Brain lactate metabolism was assessed by quantification of elevated CMD lactate samples (>4 mmol/L); these were matched to CMD pyruvate and PbtO2 values and dichotomized as glycolytic (CMD pyruvate > 119 μmol/L vs. low pyruvate) and hypoxic (PbtO2 < 20 mm Hg vs. nonhypoxic). Using perfusion computed tomography (CT), brain perfusion was categorized as oligemic, normal, or hyperemic, and was compared with CMD and PbtO2 data. Samples with elevated CMD lactate were frequently observed (41 ±8%), and we found that brain lactate elevations were predominantly associated with glycolysis and normal PbtO2 (73 ± 8%) rather than brain hypoxia (14 ±6%). Furthermore, glycolytic lactate was always associated with normal or hyperemic brain perfusion, whereas all episodes with hypoxic lactate were associated with diffuse oligemia. Our findings suggest predominant nonischemic cerebral extracellular lactate release after TBI and support the concept that lactate may be used as an energy substrate by the injured human brain.

scholarly journals A wavelet frame constrained total generalized variation model for imaging conductivity distribution

2021 ◽  
Vol 0 (0) ◽  
pp. 0
Author(s):  
Yanyan Shi ◽  
Zhiwei Tian ◽  
Meng Wang ◽  
Xiaolong Kong ◽  
Lei Li ◽  
...  
Keyword(s):  
Regularization Method ◽  
Variation Method ◽  
Total Variation Regularization ◽  
Wavelet Frame ◽  
Impedance Tomography ◽  
Conductivity Distribution ◽  
Total Generalized Variation ◽  
Staircase Effect ◽  
Ill Posed ◽  
Generalized Variation

<p style='text-indent:20px;'>Electrical impedance tomography (EIT) is a sensing technique with which conductivity distribution can be reconstructed. It should be mentioned that the reconstruction is a highly ill-posed inverse problem. Currently, the regularization method has been an effective approach to deal with this problem. Especially, total variation regularization method is advantageous over Tikhonov method as the edge information can be well preserved. Nevertheless, the reconstructed image shows severe staircase effect. In this work, to enhance the quality of reconstruction, a novel hybrid regularization model which combines a total generalized variation method with a wavelet frame approach (TGV-WF) is proposed. An efficient mean doubly augmented Lagrangian algorithm has been developed to solve the TGV-WF model. To demonstrate the effectiveness of the proposed method, numerical simulation and experimental validation are conducted for imaging conductivity distribution. Furthermore, some comparisons are made with typical regularization methods. From the results, it can be found that the proposed method shows better performance in the reconstruction since the edge of the inclusion can be well preserved and the staircase effect is effectively relieved.</p>

Mumford-Shah Model Based on Weighted Total Generalized Variation

2012 ◽  
Vol 38 (12) ◽  
pp. 1913 ◽  
Author(s):  
Wen-Juan ZHANG ◽  
Xiang-Chu FENG ◽  
Xu-Dong WANG
Keyword(s):  
Total Generalized Variation ◽  
Model Based ◽  
Generalized Variation

Multiband image fusion using total generalized variation regularization

2021 ◽  
Author(s):  
Jun Liang ◽  
Han Pan ◽  
Ying Ya ◽  
Zhongliang Jing ◽  
Lingfeng Qiao
Keyword(s):  
Image Fusion ◽  
Total Generalized Variation ◽  
Generalized Variation
Sign in / Sign up

Export Citation Format

Share Document