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Ultra-low Dose PET Imaging Challenge 2022 [article]

Kuangyu Shi, Rui Guo, Song Xue, Axel Rominger, Biao Li
2022 Zenodo  
This challenge has been announced in the preconference workshop in IEEE NSS&MIC 2021 organized by Kuangyu Shi.  ...  Kuangyu Shi: Dept. Nuclear Medicine, University of Bern/CAMP, Dept. Informatics, Technical University of Munich Rui Guo: Dept.  ... 
doi:10.5281/zenodo.6361846 fatcat:dddzqh6kzbdhdgodryrpocbev4

SynNet: Structure-Preserving Fully Convolutional Networks for Medical Image Synthesis [article]

Deepa Gunashekar, Sailesh Conjeti, Abhijit Guha Roy, Nassir Navab, Kuangyu Shi
2018 arXiv   pre-print
Cross modal image syntheses is gaining significant interests for its ability to estimate target images of a different modality from a given set of source images,like estimating MR to MR, MR to CT, CT to PET etc, without the need for an actual acquisition.Though they show potential for applications in radiation therapy planning,image super resolution, atlas construction, image segmentation etc.The synthesis results are not as accurate as the actual acquisition.In this paper,we address the
more » ... of multi modal image synthesis by proposing a fully convolutional deep learning architecture called the SynNet.We extend the proposed architecture for various input output configurations. And finally, we propose a structure preserving custom loss function for cross-modal image synthesis.We validate the proposed SynNet and its extended framework on BRATS dataset with comparisons against three state-of-the art methods.And the results of the proposed custom loss function is validated against the traditional loss function used by the state-of-the-art methods for cross modal image synthesis.
arXiv:1806.11475v1 fatcat:7e32ltakhnec3d6hz6qouvhrwm

Editorial: Artificial Intelligence in Positron Emission Tomography

Hanyi Fang, Kuangyu Shi, Xiuying Wang, Chuantao Zuo, Xiaoli Lan
2022 Frontiers in Medicine  
Edited and reviewed by: Giorgio Treglia, Ente Ospedaliero Cantonale (EOC), Switzerland Copyright © 2022 Fang, Shi, Wang, Zuo and Lan.  ...  PubMed Abstract | CrossRef Full Text | Google Scholar Keywords: artificial intelligence, molecular imaging, positron emission tomography, oncology, neurology Citation: Fang H, Shi  ... 
doi:10.3389/fmed.2022.848336 pmid:35174194 pmcid:PMC8841845 fatcat:dekkwetqinasdkr6fskp35ju4y

Finite-Time Transport Structures of Flow Fields

Kuangyu Shi, Holger Theisel, Tino Weinkauf, Hans-Christian Hege, Hans-Peter Seidel
2008 2008 IEEE Pacific Visualization Symposium  
Modern experimental and computational fluid mechanics are increasingly concerned with the structure nature of fluid motion. Recent research has highlighted the analysis of one transport structure which is called Lagrangian coherent structure. However, the quantity nature of the flow transport is still unclear. In this paper, we focus on the transport characteristics of physical quantities and propose an approach to visualize the finite-time transport structure of quantity advection. This is
more » ... lar to an integral convolution over a scalar field along path-lines of a flow field. Applied to a wellchosen set of physical quantity fields this yields structures giving insights into the dynamical processes of the underlying flow. We demonstrate our approach on a number of test data sets.
doi:10.1109/pacificvis.2008.4475460 dblp:conf/apvis/ShiTWHS08 fatcat:ziiqv5m4ubgrjon4hjaimsjxw4

Direct Parametric Image Reconstruction of Rapid Multi-tracer PET [chapter]

Xiaoyin Cheng, Nassir Navab, Sibylle I. Ziegler, Kuangyu Shi
2013 Lecture Notes in Computer Science  
The separation of multiple PET tracers within an overlapped scan based on intrinsic difference of pharmacokinetics is challenging due to the limited SNR of PET measurements and high complexity of fitting models. This study developed a novel direct parametric reconstruction method by integrating a multi-tracer model with reduced number of fitting parameters into image reconstruction. To incorporate the multitracer model, we adopted EM surrogate functions for the optimization of the penalized
more » ... likelihood. The algorithm was validated on realistic simulation phantoms and real rapid [ 18 F]FDG and [ 18 F]FLT PET imaging of mice with lymphoma mouse tumor. Both results have been compared with conventional methods and demonstrated evident improvements for the separation of multiple tracers.
doi:10.1007/978-3-642-40760-4_20 fatcat:kl3guftlsra4pnbboebcrqml6q

Translational Molecular Imaging Computing: Advances in Theories and Applications

Jinchao Feng, Wenxiang Cong, Kuangyu Shi, Shouping Zhu, Jun Zhang
2016 BioMed Research International  
Jinchao Feng Wenxiang Cong Kuangyu Shi Shouping Zhu Jun Zhang presented a feasible region extraction strategy based on a double mesh. To increase computational efficiency, D.  ... 
doi:10.1155/2016/1569605 pmid:28097127 pmcid:PMC5206409 fatcat:apwqvywt3bandekcs2ev6igrjy

Editorial: Translational Advances in Alzheimer's, Parkinson's, and Other Neurodegenerative Dementias

Jiehui Jiang, Kuangyu Shi, Fangyu Peng, Chih-Yu Hsu, Woon-Man Kung
2022 Frontiers in Aging Neuroscience  
Copyright © 2022 Jiang, Shi, Peng, Hsu and Kung. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).  ... 
doi:10.3389/fnagi.2022.858467 pmid:35370606 pmcid:PMC8968693 fatcat:mmr6udrh3fhghlrpqhpgjreg2u

Frequency-Dependent Relationship Between Resting-State fMRI and Glucose Metabolism in the Elderly

Fangyang Jiao, Zhongzhan Gao, Kuangyu Shi, Xize Jia, Ping Wu, Chengfeng Jiang, Jingjie Ge, Hui Su, Yihui Guan, Shenxun Shi, Yu-Feng Zang, Chuantao Zuo
2019 Frontiers in Neurology  
Both glucose metabolism and resting-state fMRI (RS-fMRI) signal reflect hemodynamic features. The objective of this study was to investigate their relationship in the resting-state in healthy elderly participants (n = 18). For RS-fMRI signal, regional homogeneity (ReHo), amplitude of low frequency fluctuations (ALFF), fractional ALFF (fALFF), and degree of centrality (DC) maps were generated in multiple frequency bands. Glucose uptake was acquired with 18F-fluorodeoxyglucose positron emission
more » ... mography (FDG-PET). Linear correlation of each pair of the FDG-PET and RS-fMRI metrics was explored both in across-voxel way and in across-subject way. We found a significant across-voxel correlation between the FDG-PET and BOLD-fMRI metrics. However, only a small portion of voxels showed significant across-subject correlation between FDG-PET and BOLD-fMRI metrics. All these results were similar across all frequency bands of RS-fMRI data. The current findings indicate that FDG-PET and RS-fMRI metrics share similar spatial pattern (significant across-voxel correlation) but have different underlying physiological importance (non-significant across-subject correlation). Specifically, FDG-PET measures the mean glucose metabolism over tens of minutes, while RS-fMRI measures the dynamic characteristics. The combination of FDG-PET and RS-fMRI provides complementary information to reveal the underlying mechanisms of the brain activity and may enable more comprehensive interpretation of clinical PET-fMRI studies. Future studies would attempt to reduce the artifacts of RS-fMRI and to analyze the dynamic feature of PET signal.
doi:10.3389/fneur.2019.00566 pmid:31191447 pmcid:PMC6549125 fatcat:g2w2fmugcvgk7mtubggsefm5mi

Editorial for the special issue of "Computational methods for molecular imaging" for computerized medical imaging and graphics

Kuangyu Shi, Fei Gao, Nassir Navab, Julia Schnabel, Pengcheng Shi, Sibylle I. Ziegler
2017 Computerized Medical Imaging and Graphics  
Shi et al.  ...  Title: Editorial for the Special Issue of "Computational Methods for Molecular Imaging" for Computerized Medical Imaging and Graphics Author: Kuangyu Shi PII: S0895-6111(17)30055-1 DOI: http://dx.doi.org  ... 
doi:10.1016/j.compmedimag.2017.06.006 pmid:28701281 fatcat:lj5xcr47srbxvmkaklizellzzu

Editorial: EEG and fMRI for Sleep and Sleep Disorders–Mechanisms and Clinical Implications

Xi-Jian Dai, Jihui Zhang, Yongjun Wang, Yan Ma, Kuangyu Shi
2021 Frontiers in Neurology  
Copyright © 2021 Dai, Zhang, Wang, Ma and Shi. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY).  ... 
doi:10.3389/fneur.2021.749620 pmid:34650514 pmcid:PMC8505688 fatcat:2xgpvl2m55ec3amcpdsh4gaatq

Coming back to the normal clinic: how has COVID-19 changed us?

Xiao Zhang, Zhen Liu, Kuangyu Shi, Xiaoli Lan
2020 European Journal of Nuclear Medicine and Molecular Imaging  
doi:10.1007/s00259-020-04906-8 pmid:32533241 pmcid:PMC7291185 fatcat:4ioxalek6ngm3p3lypg2yjwpdm

The Mechanism of Downregulated Interstitial Fluid Drainage Following Neuronal Excitation

Yuanyuan Li, Hongbin Han, Kuangyu Shi, Dehua Cui, Jun Yang, Ian Leigh Alberts, Lan Yuan, Guomei Zhao, Rui Wang, Xianjie Cai, Ze Teng
2020 Aging and Disease  
The drainage of brain interstitial fluid (ISF) has been observed to slow down following neuronal excitation, although the mechanism underlying this phenomenon is yet to be elucidated. In searching for the changes in the brain extracellular space (ECS) induced by electrical pain stimuli in the rat thalamus, significantly decreased effective diffusion coefficient (DECS) and volume fraction (α) of the brain ECS were shown, accompanied by the slowdown of ISF drainage. The morphological basis for
more » ... uctural changes in the brain ECS was local spatial deformation of astrocyte foot processes following neuronal excitation. We further studied aquaporin-4 gene (APQ4) knockout rats in which the changes of the brain ECS structure were reversed and found that the slowed DECS and ISF drainage persisted, confirming that the down-regulation of ISF drainage following neuronal excitation was mainly attributable to the release of neurotransmitters rather than to structural changes of the brain ECS. Meanwhile, the dynamic changes in the DECS were synchronized with the release and elimination processes of neurotransmitters following neuronal excitation. In conclusion, the downregulation of ISF drainage following neuronal excitation was found to be caused by the restricted diffusion in the brain ECS, and DECS mapping may be used to track the neuronal activity in the deep brain.
doi:10.14336/ad.2020.0224 pmid:33269097 pmcid:PMC7673848 fatcat:wqssnklfgncrxdrm7nqtltoyiy

Metabolic connectivity for differential diagnosis of dementing disorders

Dmitry Titov, Janine Diehl-Schmid, Kuangyu Shi, Robert Perneczky, Na Zou, Timo Grimmer, Jing Li, Alexander Drzezga, Igor Yakushev
2016 Journal of Cerebral Blood Flow and Metabolism  
Presently, visual and quantitative approaches for image-supported diagnosis of dementing disorders rely on regional intensity rather than on connectivity measurements. Here, we test metabolic connectivity for differentiation between Alzheimer's disease (AD) and frontotemporal lobar degeneration (FTLD). Positron emission tomography with 18F-fluorodeoxyglucose was conducted in 47 patients with mild AD, 52 patients with mild FTLD, and 45 healthy elderly subjects (HS). Sparse inverse covariance
more » ... mation and selection were used to identify patterns of metabolic, inter-subject covariance on the basis of 60 regional values. Relative to the HS group, significantly more pathological within-lobe connections were found in the parietal lobe of patients with AD, and in the frontal and temporal lobes of subjects with FTLD. Relative to the FTLD group, more pathological connections between the parietal and temporal lobe were found in the AD group. The obtained connectivity patterns differentiated between two patients groups with an overall accuracy of 83%. Linear discriminant analysis and univariate methods provided an accuracy of 74% and 69%, respectively. There are characteristic patterns of abnormal metabolic connectivity in mild AD and FTLD. Such patterns can be utilized for single subject analyses and might be more accurate in the differential diagnosis of dementing disorders than traditional intensity-based analyses.
doi:10.1177/0271678x15622465 pmid:26721391 pmcid:PMC5363743 fatcat:mt4hoh7xvbfx5g6p6e4dhwztam

Increased TLR4 Expression Aggravates Sepsis by Promoting IFN-γ Expression in CD38−/− Mice

Qi Li, Chenyi Wu, Zhenlong Liu, Huiqing Zhang, Yuna Du, Yuxiang Liu, Kuangyu Song, Qiaofa Shi, Rong Li
2019 Journal of Immunology Research  
Gram-negative bacterial sepsis accounts for up to 50% worldwide sepsis that causes hospital mortality. Acute kidney injury (AKI), a common complication of Gram-negative bacterial sepsis, is caused by Toll-like receptor 4 (TLR4) activation. Lipopolysaccharide (LPS) is an endotoxin in Gram-negative bacteria and is recognized specifically by TLR4, which initiates innate immune response. Also, TLR4 signaling pathway activation is essential in response to LPS infection. CD38 is one of the well-known
more » ... regulators of innate immunity, whose dysregulation contributes to sepsis. Many studies have proven that an attenuated Gram-positive bacterium induces sepsis in a CD38-blocking model. However, the pathogenesis of Gram-negative bacteria-induced sepsis in a CD38−/− mouse model remains unclear. The aim of this study is to investigate whether kidney injury is still attenuated in a LPS-induced CD38−/− sepsis model and identify the potential mechanism. We assess the severity of kidney injury related to proinflammatory cytokine expressions (IFN-γ, TNF-α, IL-1β, and IL-6) in WT and CD38−/− mice. Our results showed more aggravated kidney damage in CD38−/− mice than in WT mice, accompanied with an increase of proinflammatory cytokine expression. In addition, compared with CD38−/−TLR4mut mice, we found an increase of TLR4 expression and mRNA expression of these cytokines in the kidney of CD38−/− mice, although only increased IFN-γ level was detected in the serum. Taken together, these results demonstrated that an increased TLR4 expression in CD38−/− mice could contribute to the aggravation of AKI through boosting of the production of IFN-γ.
doi:10.1155/2019/3737890 fatcat:6uwfr3cbt5ck5fmdoy3puixbrq

Sparse Dose Painting Based on a Dual-Pass Kinetic-Oxygen Mapping of Dynamic PET Images [chapter]

Kuangyu Shi, Sabrina T. Astner, Liang Sun, Nassir Navab, Fridtjof Nüsslin, Peter Vaupel, Jan J. Wilkens
2011 Lecture Notes in Computer Science  
Development of molecular imaging such as positron-emission tomography (PET) offers an opportunity to optimize radiotherapy treatment planning by conforming the dose distribution to physiological details within tumors, so called dose painting. Quantification of the acquired images and an efficient and practical dose prescription remain two key questions in this field. This paper proposes a novel framework to optimize the dose prescription based on dual-pass modeling of dynamic [ 18 F]FMISO PET
more » ... ages. An optimization algorithm for sparse dose painting (SDP) is developed by minimizing a linear combination of two terms corresponding to the efficiency and total variation of the dose distribution with the constraint of a constant mean dose. Dose efficiency is defined using the linear-quadratic model. The radiosensitivity given by the oxygen tension is estimated using a dual-pass kinetic-oxygen mapping strategy. This is achieved by integrating a realistic [ 18 F]FMISO PET imaging simulation model, which can simulate the distribution of oxygen and tracer under the same tumor microenvironment setting. The algorithm was compared with a typical dose painting by number (DPBN) method in one data set of a patient with head and neck cancer.
doi:10.1007/978-3-642-23623-5_61 fatcat:m3hspp3vx5aspct2daei6npbay
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