| Computer # |
| 2856.
 | 81 | Accelerating Prostate DWI Scans: A Combination of Local SVD and Deep Learning for Enhanced Denoising Lukas Bolay1,2, Laura Pfaff1,2, Tobias Würfl2, Elisabeth Weiland2, Omar Darwish2, Oleg Shagalov2, Marcel-Dominik Nickel2, and Andreas Maier1
1Pattern Recognition Lab, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany, 2Siemens Healthineers AG, Erlangen, Germany Keywords: DWI/DTI/DKI, Prostate, Diffusion Denoising, Sparse and Low-Rank Models Motivation: Diffusion-weighted MR images often suffer from low signal-to-noise ratio, particularly at high b-values, diminishing their diagnostic value. To counter this, multiple repetitions per diffusion direction are typically acquired and averaged, which is time-consuming and prone to motion artifacts. Goal(s): Present a method that reduces the required number of repetitions in DWI, thus shortening scan times, while preserving diagnostic value. Approach: The repetitions in DWI are jointly denoised through a combination of local Singular Value Decomposition and deep-learning-based denoising. Results: Our evaluations indicate that this approach outperforms competing methods, offering a potential solution to the problem of prolonged acquisition times in DWI. Impact: By combining local singular value decomposition with deep-learning-based denoising techniques, the necessary number of repetitions for the acquisition of diffusion-weighted MR images is substantially decreased and thus the acquisition is accelerated, while retaining comparable image quality. |
| 2857.
 | 82 | Non-complete Recovery of White Matter Diffusion Metrics at One Year Post-Radiotherapy: Implications for Radiation-Induced Necrosis Risk Jie Pan1, Ziru Qiu2,3, Gui Fu1, Jiahui liang1, Xinyuan Zhang2,3, and Xiaofei Lv1
1Sun Yat-Sen University Cancer Center, Guangzhou, China, 2School of Biomedical Engineering, Southern Medical University, Guangzhou, China, 3Guangdong Provincial Key Laboratory of Medical Image Processing and Guangdong Province Engineering Laboratory for Medical Imaging and Diagnostic Technology, Southern Medical University, Guangzhou, China Keywords: DWI/DTI/DKI, Head & Neck/ENT, nasopharyngeal carcinoma, radiation-induced TL necrosis, multi-shell diffusion MRI, automated fiber-tract quantification, Cox proportional-hazards regression model, Normal Tissue Complication Probability Motivation: Radiotherapy for nasopharynx carcinoma (NPC) can lead to various white matter (WM) abnormalities. Goal(s): Explores the connection between WM injuries and temporal lobe necrosis (TLN) and optimizing radiotherapy (RT) regimens for NPC. Approach: Multi-shell diffusion MRI (MS-dMRI) quantification using automated fiber-tract quantification (AFQ). Diffusion metrics alterations analysis using rANOVA. TLN risk factors identification using Cox regression models. Optimal RT regiments development using normal tissue complication probability (NTCP) models. Results: Most TL WM tract segments showed a "decrease/increase without complete recovery" pattern. MD_UF.L.1, NDI_CH.L.1, and NDI_ILF.R.1 were identified as TLN risk predictors. Tolerance dose for D10cc.L, D20cc.L and D10cc.R were revealed for optimal regiments. Impact: Our findings highlight the importance of "decrease/increase without
complete recovery" pattern in TL WM tract segment impairments in TLN
development. Identifying high-risk WM tract segments and their tolerance
doses can aid in optimizing radiotherapy regimens for NPC. |
| 2858.
 | 83 | Denoising diffusion MRI with an improved non-local principal component analysis approach Xinyu Ye1, Xiaodong Ma2, Ziyi Pan3, Zhe Zhang4, Edward Auerbach5, Hua Guo6, Kâmil Uğurbil5, and Xiaoping Wu5
1Wellcome Centre for Integrative Neuroimaging, FMRIB, Nuffield Department of Clinical Neurosciences, Univeristy of Oxford, Oxford, United Kingdom, 2Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT, United States, 3United Imaging, Shanghai, China, 4Tiantan Neuroimaging Center of Excellence, Beijing Tiantan Hospital, Capital Medical University, Beijing, China, 5Center for Magnetic Resonance Research, Radiology, Medical School, University of Minnesota, Minneapolis, MN, United States, 6Tsinghua University, Beijing, China Keywords: DWI/DTI/DKI, Diffusion/other diffusion imaging techniques Motivation: Previously, we proposed an improved 2-step non-local principal component analysis (PCA) approach and demonstrated its utility for denoising diffusion MRI with many diffusion directions. Goal(s): Our goal here was to investigate how our approach would benefit diffusion tensor MRI (DTI) with a few diffusion directions. Approach: we evaluated our approach’s denoising performances using both simulation and human-data experiments, and compared the results to those obtained with existing local-PCA-based methods. Results: Our approach substantially enhanced image quality relative to the noisy counterpart, yielding improved performances for estimation of relevant DTI metrics. It also outperformed existing local-PCA-based methods in reducing noise while preserving anatomic details. Impact: Capable of improving image quality for DTI
with reduced diffusion directions, our improved non-local PCA denoising approach
is believed to have utility for many applications, especially those targeting
quality DTI or parametric mapping or both within a clinically relevant
timeframe. |
| 2859.
 | 84 | Assessment of Glymphatic Function in Acute High Altitude Reaction: by diffusion tensor image analysis along the perivascular space (DTI-ALPS) Ya Guo1, HaiHua Bao1, Shengbao Wen1, Tao Tao1, Changyou Long1, Shaoxin Xiang2, Yuxin Yang2, and Shipei He2
1Department of Medical Imaging Center, Qinghai University Affiliated Hospital, Xining, China, 2United Imaging Research Institute of Intelligent Imaging, Beijing, China Keywords: DWI/DTI/DKI, Brain, Diffusion tensor image analysis along the perivascular space (DTI-ALPS),Acute high altitude reaction Motivation: Diffusion tensor image analysis along the perivascular space(DTI-ALPS) is a novel non-invasive assessment of the activity of the human brain's lymphoid system, which is currently being used to assess the function of the lymphoid system in patients with acute high altitude reaction(AHAR). Goal(s): To evaluate the activity of the glymphatic system in patients with AHAR using DTI-ALPS, and explore the relationship between lymphoid function and disease severity. Approach: Recruited 5 patients with AHAR and calculated ALPS index, Pearson correlation analysis were used for evaluating relationship between ALPS index and diagnostic scoring. Results:
There was a significant correlation between DTI-ALPS and disease scores(r=-0.964 P=0.005). Impact: DTI-ALPS is a novel non-invasive assessment of the activity of the human brain's lymphoid system, which is currently being used to assess the function of the lymphoid system in patients with AHAR. |
| 2860.
 | 85 | Short-term White Matter Microstructural Changes in Young Adults Infected with SARS-COV-2 Omicron Variant Jialan Zheng1, Jiachen Liu2, Cong Yang3, Hongjia Yang2, Zihan Li2, Haoxiang Li2, Haiyan Ding2, Xihai Zhao2, and Qiyuan Tian2
1Tanwei College, Tsinghua University, Beijing, China, 2Department of Biomedical Engineering, Tsinghua University, Beijing, China, 3Tsinghua Laboratory of Brain and Intelligence, Tsinghua University, Beijing, China Keywords: DWI/DTI/DKI, COVID-19 Motivation: The prevalence of the SARS-CoV-2 Omicron variant poses a significant concern. It is important to investigate its potential repercussions on public health. Goal(s): To evaluate the impacts of Omicron variant on white matter microstructure. Approach: Diffusion MRI data were acquired on young adults tested positive for COVID-19 antigen or nucleic acid within two months and with non-hospitalized mild symptoms during infection. Tract-wise DTI metrics were used to quantify microstructural properties. Results: SARS-CoV-2 infection leads to significant short-term microstructural changes in the white matter, which exhibit spatial and gender disparity. Impact: This study provides evidence for short-term microstructural changes induced by SARS-COV-2 Omicron variant infection, which motivates further investigation to uncover the mechanisms by which viruses invade the nervous system. |
| 2861.
 | 86 | Relationship Between Apparent Fiber Density in Corpus Callosum and Cognitive Function. Naoya Hayashi1,2, Daisuke Yoshimaru3,4, Shuhei Shibukawa3,5, Eri Arizono3, Yoichi Araki1, Naoki Kawaguchi1, Soichiro Shimizu6, and Kazuhiro Saito3
1Department of Radiology, Tokyo Medical University Hospital, Tokyo, Japan, 2Department of Radiological Sciences, Graduate School of Health Sciences, Tokyo Metropolitan University, Tokyo, Japan, 3Department of Radiology, Tokyo Medical University, Tokyo, Japan, 4Division of Regenerative Medicine, Jikei University School of Medicine, Tokyo, Japan, 5Department of Radiological Technonlogy, Faculty of Health Science, Juntendo University, Tokyo, Japan, 6Department of Geriatric Medicine, Tokyo Medical University, Tokyo, Japan Keywords: DWI/DTI/DKI, Diffusion Tensor Imaging Motivation: Evaluation of fiber density in the corpus callosum (CC) is expected to show a higher sensitivity in relation to cognitive function than changes in volume. Goal(s): The goal is to clarify the association between the volume and AFD of the CC5 region and neuropsychological test scores. Approach: We examined the relationship between neuropsychological test scores, and calculated AFD and CC volume for 180 patients with suspected dementia. Results: CC volume showed no significant association with neuropsychological test scores. On the other hand, AFD showed associations with several neuropsychological tests. Impact: This study demonstrated that AFD correlated better with cognitive function than the previously reported CC volume. It was indicated the superior sensitivity of AFD in assessing cognitive function in dementia diagnosis. |
| 2862.
 | 87 | Glymphatic system impairment in Type 2 diabetes mellitus associated with cognitive function Jie Gao1, Peichun Pan1, Dongsheng Zhang1, Xuejiao Yan1, Min Tang1, Jing Li1, Xin Zhang1, Kai Ai2, Peng Wu3, Xiaoyan Lei1, and Xiaoling Zhang1
1Department of MRI, Shaanxi Provincial People’s Hospital, Xi’an, China, 2Philips Healthcare, Xi’an, China, 3Philips Healthcare, Shanghai, China Keywords: DWI/DTI/DKI, Diabetes Motivation: T2DM has emerged as an important risk factor for cognitive impairment. However, the neuropathological basis of the cognitive impairment associated with T2DM is still unclear. Goal(s): To investigate whether the impaired glymphatic function is one of the mechanisms in T2DM-associated cognitive dysfunction. Approach: We compared the glymphatic function by calculating the diffusion along the perivascular space based on a diffusion tensor image, namely the DTI-ALPS index between HCs and patients with T2DM and investigated the relationship between DTI-ALPS index and cognitive functions. Results: The lower DTI-ALPS index was found in patients with T2DM, and DTI-ALPS index was correlated with worse cognitive performance. Impact: DTI-ALPS
index may be applied as a useful indicator to evaluate the glymphatic system
function. The impaired glymphatic system in patients with T2DM may provide a
new perspective for understanding the pathophysiology of T2DM related cognitive
impairment. |
| 2863.
 | 88 | Resting-state fMRI network efficiency mediates the association between glymphatic system and cognition function in OSAHS: a DTI-ALPS study Zhenliang Xiong1,2, Mingxian Bai1, Zhongxin Wang1, Rongpin Wang1, Lisha Nie3, and Xianchun Zeng1
1Department of Radiology, Guizhou Provincial People’s Hospital, Guiyang, China, 2College of Computer Science and Technology, Guizhou University, Guiyang, China, 3GE HealthCare MR Research, Beijing, China Keywords: DWI/DTI/DKI, Diffusion Tensor Imaging Motivation: Obstructive Sleep Apnea Hypopnea Syndrome (OSAHS) is a serious sleep disorder linked to cognitive impairment. This study investigates the glymphatic system's role in OSAHS and its impact on cognition. Goal(s): Explore glymphatic system changes in OSAHS and their influence on cognitive function. We aim to uncover the mechanisms connecting OSAHS and cognitive issues. Approach: We use DTI-ALPS and rs-fMRI to assess the glymphatic system and brain network properties. Correlations and mediation analysis examine the link between glymphatic function, cognitive abilities, and OSAHS severity. Results: OSAHS patients exhibit reduced glymphatic function, affecting cognitive performance. Impact: This study may enhance comprehension of cognitive problems in OSAHS, suggesting dementia risk. It could inform early intervention, enhancing OSAHS patients' quality of life. |
| 2864.
 | 89 | Dynamic Changes of Cortical Microstructure in Nasopharyngeal Carcinoma Patients After Radiotherapy: A Multi-Shell Diffusion Imaging Study Ziru Qiu1, Yuhao Lin2, Xiaofei Lv3, Jiahui Liang3, Gui Fu3, Jie Pan3, Yanqiu Feng1, and Xinyuan Zhang1
1School of Biomedical Engineering, Southern Medical University, Guangzhou, China, 2Departments of Nuclear Medicine, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China, 3Department of Medical Imaging, Sun Yat-sen University Cancer Center, Guangzhou, China Keywords: DWI/DTI/DKI, Gray Matter, Nasopharyngeal carcinoma, radiation-induced brain injury, GM-based spatial statistics Motivation: Radiotherapy for nasopharyngeal carcinoma induces brain structural abnormalities, altering cortical microstructure. Goal(s): Longitudinally explore dynamic cortical microstructure changes over one year after Radiotherapy. Approach: We performed GM-based spatial statistics analysis (GBSS) on DTI and NODDI data, utilizing nonparametric permutation inference to identify dynamic alterations in diffusion metrics. Cortical regions were located in gray matter clusters by referring to the Desikan-Killiany atlas.
Results: Bilateral temporal lobe MD reduced significantly, and NDI increased notably at six months post-RT, and these changes remained with larger clusters at 12 months. The affected gray matter regions included the entorhinal cortex, temporal pole, inferior temporal gyrus, and fusiform gyrus.
Impact: The
combination of DTI and NODDI allows for a more comprehensive
understanding of the patterns of cortical microstructural changes induced by RT,
offering the potential for early interventions in radiation-induced brain
injury. |
| 2865.
 | 90 | Feasibility of high b value in vivo cardiac diffusion in humans with ultra-high gradient strength scanner Thomas Garrett1, Danielle Kara1, Shi Chen1, Yuchi Liu2, Xiaoming Bi3, and Christopher Nguyen1,4,5,6
1Cardiovascular Innovation Research Center, Heart Vascular Thoracic Institute, Cleveland Clinic, Cleveland, OH, United States, 2Siemens Medical Solutions USA, Inc., Cleveland, OH, United States, 3Siemens Medical Solutions USA, Inc, Los Angeles, CA, United States, 4Cardiovascular Medicine, Heart Vascular Thoracic Institute, Cleveland Clinic, Cleveland, OH, United States, 5Imaging Institute, Cleveland Clinic, Cleveland, OH, United States, 6Department of Biomedical Engineering, Case Western Reserve University & Cleveland Clinic, Cleveland, OH, United States Keywords: DWI/DTI/DKI, Diffusion Tensor Imaging Motivation: New technology allows for higher gradient strengths and therefore higher b-values to be used in cardiac diffusion tensor imaging (cDTI). Goal(s): To compare cDTI parameter maps for the current standard and increased b-values both qualitatively and quantitatively. Approach: Two cDTI datasets with b=500 s/mm2 and b=1000s/mm2 were acquired from nine healthy subjects. The resulting DTI parameter maps were compared through visual analysis and a series of paired t-tests. Results: Both qualitative and quantitative data between parameter maps show improved detail and higher precision in high b-value data compared to standard b-value data. Impact: A new ultra-high-performance 3T MR system allows for higher diffusion gradients and b-values. Our study shows high b-values (b=1000 s/mm2) lead to higher levels of detail and precision in cardiac DTI of healthy subjects compared to standard b-values (b=500 s/mm2). |
| 2866.
 | 91 | Evaluation of Microstructural Brain Abnormalities and Cognitive Impairment of OSAHS patients with axial and radial kurtosis from DKI Ning Zhang1, Kun Peng1, and Jinxia Guo2
1The Sixth Hospital of Shanxi Medical University(General Hospital of TISCO), Taiyuan, China, 2GE Healthcare, Beijing, China Keywords: DWI/DTI/DKI, Nervous system, Obstructive sleep apnea-hypopnea syndrome; cognitive function Motivation: Microstructural brain changes resulted from obstructive sleep apnea hypopnea syndrome（OSAHS）related cognitive impairment can help to understand the potential neuropathological mechanism. Goal(s): To assess the brain microstructural alteration in patients with OSAHS using DKI imaging. Approach: 33 OSAHS patients and 33 healthy controls were performed DKI/3D-T1WI MRI imaging. The AK and RK in different brain regions were extracted. Results: Significant differences were found in AK and RK values in various brain regions for OSAHS group compared to HC group. Abnormal changes in some crucial brain regions were found to be correlated with MoCA score and sleep parameters. Impact: Altered AK and RK in brain regions associated with the microstructural change in OSAHS, such as demyelination and axonal destruction. The correlation of respiratory parameters and scoring indicators is conducive to more objective assessment for cognitive level of patients. |
| 2867.
 | 92 | Repeatability and reproducibility of diffusional variance decomposition (DIVIDE) imaging Shohei Inui1, Tsuyoshi Ueyama2, Yuichi Suzuki2, Tetsuya Wakayama3, and Osamu Abe1
1Radiology, The University of Tokyo, Tokyo, Japan, 2Radiology, The University of Tokyo Hospital, Tokyo, Japan, 3GE HealthCare, Tokyo, Japan Keywords: DWI/DTI/DKI, Diffusion/other diffusion imaging techniques Motivation: Novel Multidimensional diffusion encoding (MDE) technique, diffusional variance decomposition (DIVIDE), may provide more detailed insights into tissue microstructure. Goal(s): To evaluate the feasibility of DIVIDE imaging for human brain. Approach: Ten healthy-subjects underwent MDE (2D-EPI sequence with 29 linear and 26 spherical b-tensors) twice using 3T-MRI. Regional values of 20 ROIs was extracted for 10 DIVIDE metrics. Coefficient of variation (CV) and interclass correlation coefficient (ICC) were calculated. Results: Intra-subject CV was less than 5% in almost all regional metrics. Intra-subject CV was lower than that of inter-subject CV in all regional metrics. ICC showed almost perfect agreements for almost all regional metrics.
Impact: Recently developed MDE technique, diffusional variance
decomposition (DIVIDE), may be reliably used for measuring diffusion metrics with a potential to provide more detailed insights into tissue
microstructure in complex tissues, such as crossing or kissing fiber
configurations in the brain. |
| 2868.
 | 93 | Investigating Postmortem Neurite Orientation Dispersion and Density Imaging Parameters and Their Influences on Deceased Human Brains Melanie Bauer1,2, Celine Berger1,2, Andrea Zirn1,2, Eva Scheurer1,2, Stefan Ropele3, and Claudia Lenz1,2
1Institute of Forensic Medicine, Department of Biomedical Engineering, University of Basel, BASEL, Switzerland, 2Institute of Forensic Medicine, Health Department Basel-Stadt, Basel, Switzerland, 3Department of Neurology, Medical University of Graz, Austria, Graz, Austria Keywords: Microstructure, Ex-Vivo Applications, NODDI Motivation: Neurite orientation dispersion and density imaging (NODDI) is expected to advance our still incomplete understanding of diffusion properties in postmortem brains. Goal(s): We examined NODDI parameters in deceased human brains in situ and investigated their associations with postmortem interval (PMI), age at death and core temperature. Approach: Ten subjects underwent postmortem in situ brain MRI, enabling NODDI analysis. Correlations between NODDI parameters and external factors were assessed. Results: The results revealed higher NODDI parameters in deceased compared to living subjects. Longer PMIs were associated with increased fractional intracellular volume (FICVF) and orientation dispersion index (ODI) values, while higher temperatures had the opposite effect. Impact: Our study expands the understanding of
postmortem brain microstructure. NODDI's potential in deceased brain analysis
and its relation to postmortem interval and temperature pave the way for further
research with applications in diagnostics and forensics. |
| 2869.
 | 94 | Multi-tissue constrained spherical deconvolution with spherical mean density estimation J-Donald Tournier1,2
1Biomedical Engineering, School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom, 2Centre for the Developing Brain, School of Biomedical Engineering and Imaging Sciences, King's College London, London, United Kingdom Keywords: Diffusion Reconstruction, Diffusion/other diffusion imaging techniques Motivation: Multi-tissue constrained spherical deconvolution (MT-CSD) average densities depend on the local fibre arrangement, as it relies on the non-negativity of the fibre orientation density functions (fODF). Goal(s): We investigate whether MT-CSD can be performed without influence of the orientation structure of fibre ODF. Approach: Using the spherical mean of each b-value shell to factor out the angular structure, we rely purely on the different tissue types' b-value dependence, with the angular part of the fODF estimated subsequently . Results: The method produces plausible, but subtly different results from 'regular' MT-CSD, which appear to be less affected by fibre arrangement. It is also substantially faster. Impact: The ability to decompose the signal based purely on its spherical mean b-value dependence may provide more reliable density estimates, though this needs further investigation. The computational efficiency of this approach may also make it more suitable for real-time use. |
| 2870.
 | 95 | Correcting the unwanted diffusion-weighting in STEAM-DWI Sequence for Time-Dependent Diffusional Kurtosis Imaging Qinfeng Zhu1, Haotian Li1, Ruicheng Ba1, Yi-Cheng Hsu2, Xu Yan2, and Dan Wu1
1Department of Biomedical Engineering, College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou, China, 2MR Collaboration, Siemens Healthcare China, Shanghai, China Keywords: DWI/DTI/DKI, Brain Motivation: Time-dependent diffusion kurtosis imaging (tDKI) enables the noninvasive mapping of transmembrane water exchange by measuring diffusion signals at varying diffusion-times. To access long diffusion-times, the diffusion-weighted STEAM sequence is typically used, in which the unwanted diffusion weighting produced by the crushers and slice selection gradients. Goal(s): We first showed that this unwanted weighting, particularly on the b0 image led to an underestimation of kurtosis. Approach: We proposed a strategy to resolve this problem by removing the crusher gradient while adding a smaller and fixed b value to the b0 acquisition. Results: Proposed strategy showed reasonable tDKI measurements in phantom and human brain experiments. Impact: This study presented an important issue of unwanted diffusion-weighting in STEAM-DWI,
which led to inaccurate estimation of tDKI-based transmembrane water exchange.
We proposed a strategy that removed the crusher and dynamically adjusting the
diffusion gradient to achieve the desired b-value. |
| 2871.
 | 96 | Robust frequency-dependent diffusional kurtosis computation using an efficient direction scheme, axisymmetric modelling and regularization Jake Hamilton1,2, Kathy Xu3,4, Nicole Geremia3,4, Vania F. Prado3,4, Marco A.M. Prado3,5, Arthur Brown3,4, and Corey A. Baron1,2
1Centre for Functional and Metabolic Mapping (CFMM), Robarts Research Institute, Western University, London, ON, Canada, 2Department of Medical Biophysics, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada, 3Translational Neuroscience Group, Robarts Research Institute, Western University, London, ON, Canada, 4Department of Anatomy & Cell Biology, Western University, London, ON, Canada, 5Department of Physiology and Pharmacology, Schulich School of Medicine and Dentistry, Western University, London, ON, Canada Keywords: Diffusion Analysis & Visualization, Microstructure Motivation: While diffusion MRI has proven to be valuable for studying tissue microstructure, there is a need to develop more sensitive and specific methods to detect microstructural changes at various spatial scales. Goal(s): To develop an acquisition and analysis scheme that can robustly compute frequency-dependent diffusional kurtosis metrics. Approach: Acquisition parameters such as a novel efficient direction scheme were presented along with an analysis pipeline that utilizes axisymmetric modelling, spatial regularization, and maximizes data usage. Results: We demonstrate the advantage of using the efficient scheme over conventional methods, and the analysis pipeline improves diffusional kurtosis map quality compared to conventionally used methods. Impact: We present an acquisition and analysis
scheme that generates robust frequency-dependent diffusional kurtosis maps,
which may offer increased sensitivity to cytoarchitectural changes that occur
at various cellular spatial scales over the course of healthy aging, and due to
pathological alterations. |