arXiv - PHYS - Medical Physics最新文献_第6页

Compartment-specific estimation of T2 and T2* with diffusion-PEPTIDE MRI 利用弥散-PEPTIDE MRI 对 T2 和 T2* 进行分区估算

arXiv - PHYS - Medical Physics Pub Date : 2024-08-19 DOI: arxiv-2408.10432

Ting Gong, Merlin J. Fair, Kawin Setsompop, Hui Zhang

{"title":"Compartment-specific estimation of T2 and T2* with diffusion-PEPTIDE MRI","authors":"Ting Gong, Merlin J. Fair, Kawin Setsompop, Hui Zhang","doi":"arxiv-2408.10432","DOIUrl":"https://doi.org/arxiv-2408.10432","url":null,"abstract":"We present a microstructure imaging technique for estimating\u0000compartment-specific T2 and T2* simultaneously in the human brain.\u0000Microstructure imaging with diffusion MRI (dMRI) has enabled the modelling of\u0000intra-neurite and extra-neurite diffusion signals separately allowing for the\u0000estimation of compartment-specific tissue properties. These\u0000compartment-specific properties have been widely used in clinical studies.\u0000However, conventional dMRI cannot disentangle differences in relaxations\u0000between tissue compartments, causing biased estimates of diffusion measures\u0000which also change with TE. To solve the problem, combined relaxometry-diffusion\u0000imaging methods have been developed in recent years, providing compartmental\u0000T2-diffusion or T2*-diffusion imaging respectively, but not T2 and T2*\u0000together. As they provide complementary information, a technique that can\u0000estimate both jointly with diffusion is appealing to neuroimaging studies. The\u0000aim of this work is to develop a method to map compartmental T2-T2*-diffusion\u0000simultaneously. Using an advanced MRI acquisition called diffusion-PEPTIDE, a\u0000novel microstructure model is proposed and a multi-step fitting method is\u0000developed to estimate parameters of interest. We demonstrate for the first time\u0000that compartmental T2, T2* can be estimated simultaneously from in vivo data.\u0000we further show the accuracy and precision of parameter estimation with\u0000simulation.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

ECG-Free Assessment of Cardiac Valve Events Using Seismocardiography 利用地震心动图对心脏瓣膜事件进行无心电图评估

arXiv - PHYS - Medical Physics Pub Date : 2024-08-18 DOI: arxiv-2408.09513

Mohammad Muntasir Rahman, Aysha Mann, Amirtaha Taebi

引用次数: 0

Applications of aligned nanofiber for tissue engineering 对齐纳米纤维在组织工程中的应用

arXiv - PHYS - Medical Physics Pub Date : 2024-08-15 DOI: arxiv-2408.07909

Gayatri Patel, Louis-S. Bouchard

引用次数: 0

A Monte Carlo assessment of the spectral performance of four types of photon counting detectors 对四种光子计数探测器光谱性能的蒙特卡罗评估

arXiv - PHYS - Medical Physics Pub Date : 2024-08-14 DOI: arxiv-2408.07538

Karl Stierstorfer, Martin Hupfer

引用次数: 0

A Finite Element Analysis Model for Magnetomotive Ultrasound Elastometry Magnet Design with Experimental Validation 磁动力超声弹性测量磁体设计的有限元分析模型及实验验证

arXiv - PHYS - Medical Physics Pub Date : 2024-08-14 DOI: arxiv-2408.07737

Jacquelline Nyakunu, Christopher T. Piatnichouk, Henry C. Russell, Niels J. van Duijnhoven, Benjamin E. Levy

{"title":"A Finite Element Analysis Model for Magnetomotive Ultrasound Elastometry Magnet Design with Experimental Validation","authors":"Jacquelline Nyakunu, Christopher T. Piatnichouk, Henry C. Russell, Niels J. van Duijnhoven, Benjamin E. Levy","doi":"arxiv-2408.07737","DOIUrl":"https://doi.org/arxiv-2408.07737","url":null,"abstract":"Objective. Magnetomotive ultrasound (MMUS) using magnetic nanoparticle\u0000contrast agents has shown promise for thrombosis imaging and quantitative\u0000elastometry via magnetomotive resonant acoustic spectroscopy (MRAS). Young's\u0000modulus measurements of smaller, stiffer thrombi require an MRAS system capable\u0000of generating forces at higher temporal frequencies. Solenoids with fewer\u0000turns, and thus less inductance, could improve high frequency performance, but\u0000the reduced force may compromise results. In this work, a computational model\u0000capable of predicting improved MRAS magnet configurations optimized for\u0000elastometry is presented and validated. Approach. Finite element analysis (FEA) was used to model the force and\u0000inductance of MRAS systems. The simulations incorporated both solenoid\u0000electromagnets and permanent magnets in three-dimensional steady-state,\u0000frequency domain, and time domain studies. Main results. The model successfully predicted a configuration in which\u0000permanent magnets could be used to increase the force supplied by an existing\u0000MRAS system. Accordingly, the displacement measured in a magnetically labeled\u0000validation phantom increased by a factor of $2.2 pm 0.3$ when the force was\u0000predicted to increase by a factor of $2.2 pm 0.2$. The model additionally\u0000identified a new solenoid configuration consisting of four smaller coils\u0000capable of providing sufficient force at higher driving frequencies. Significance. These results indicate two methods by which MRAS systems could\u0000be designed to deliver higher frequency magnetic forces without the need for\u0000experimental trial and error. Either the number of turns within each solenoid\u0000could be reduced while permanent magnets are added at precise locations, or a\u0000larger number of smaller solenoids could be used. These findings overcome a key\u0000challenge toward the goal of thrombosis elastometry via MMUS.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

DuDoCROP: Dual-Domain CLIP-Assisted Residual Optimization Perception Model for CT Metal Artifact Reduction DuDoCROP：用于减少 CT 金属伪影的双域 CLIP 辅助残留优化感知模型

arXiv - PHYS - Medical Physics Pub Date : 2024-08-14 DOI: arxiv-2408.14342

Xinrui Zhang, Ailong Cai, Lei Li, Bin Yan

{"title":"DuDoCROP: Dual-Domain CLIP-Assisted Residual Optimization Perception Model for CT Metal Artifact Reduction","authors":"Xinrui Zhang, Ailong Cai, Lei Li, Bin Yan","doi":"arxiv-2408.14342","DOIUrl":"https://doi.org/arxiv-2408.14342","url":null,"abstract":"Metal artifacts in computed tomography (CT) imaging pose significant\u0000challenges to accurate clinical diagnosis. The presence of high-density\u0000metallic implants results in artifacts that deteriorate image quality,\u0000manifesting in the forms of streaking, blurring, or beam hardening effects,\u0000etc. Nowadays, various deep learning-based approaches, particularly generative\u0000models, have been proposed for metal artifact reduction (MAR). However, these\u0000methods have limited perception ability in the diverse morphologies of\u0000different metal implants with artifacts, which may generate spurious anatomical\u0000structures and exhibit inferior generalization capability. To address the\u0000issues, we leverage visual-language model (VLM) to identify these morphological\u0000features and introduce them into a dual-domain CLIP-assisted residual\u0000optimization perception model (DuDoCROP) for MAR. Specifically, a dual-domain\u0000CLIP (DuDoCLIP) is fine-tuned on the image domain and sinogram domain using\u0000contrastive learning to extract semantic descriptions from anatomical\u0000structures and metal artifacts. Subsequently, a diffusion model is guided by\u0000the embeddings of DuDoCLIP, thereby enabling the dual-domain prior generation.\u0000Additionally, we design prompt engineering for more precise image-text\u0000descriptions that can enhance the model's perception capability. Then, a\u0000downstream task is devised for the one-step residual optimization and\u0000integration of dual-domain priors, while incorporating raw data fidelity.\u0000Ultimately, a new perceptual indicator is proposed to validate the model's\u0000perception and generation performance. With the assistance of DuDoCLIP, our\u0000DuDoCROP exhibits at least 63.7% higher generalization capability compared to\u0000the baseline model. Numerical experiments demonstrate that the proposed method\u0000can generate more realistic image structures and outperform other SOTA\u0000approaches both qualitatively and quantitatively.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

ACCELERATION: Sequentially-scanning DECT Imaging Using High Temporal Resolution Image Reconstruction And Temporal Extrapolation 加速：利用高时间分辨率图像重建和时间外推法进行顺序扫描 DECT 成像

arXiv - PHYS - Medical Physics Pub Date : 2024-08-12 DOI: arxiv-2408.06163

Qiaoxin Li, Dong Liang, Yinsheng Li

{"title":"ACCELERATION: Sequentially-scanning DECT Imaging Using High Temporal Resolution Image Reconstruction And Temporal Extrapolation","authors":"Qiaoxin Li, Dong Liang, Yinsheng Li","doi":"arxiv-2408.06163","DOIUrl":"https://doi.org/arxiv-2408.06163","url":null,"abstract":"Dual-energy computed tomography (DECT) has been widely used to obtain\u0000quantitative elemental composition of imaged subjects for personalized and\u0000precise medical diagnosis. Compared with existing high-end DECT leveraging\u0000advanced X-ray source and/or detector technologies, the use of the\u0000sequentially-scanning data acquisition scheme to implement DECT may make\u0000broader impact on clinical practice because this scheme requires no specialized\u0000hardware designs. However, since the concentration of iodinated contrast agent\u0000in the imaged subject varies over time, sequentially-scanned data sets acquired\u0000at two tube potentials are temporally inconsistent. As existing material\u0000decomposition approaches for DECT assume that the data sets acquired at two\u0000tube potentials are temporally consistent, the violation of this assumption\u0000results in inaccurate quantification accuracy of iodine concentration. In this\u0000work, we developed a technique to achieve sequentially-scanning DECT imaging\u0000using high temporal resolution image reconstruction and temporal extrapolation,\u0000ACCELERATION in short, to address the technical challenge induced by temporal\u0000inconsistency of sequentially-scanned data sets and improve iodine\u0000quantification accuracy in sequentially-scanning DECT. ACCELERATION has been\u0000validated and evaluated using numerical simulation data sets generated from\u0000clinical human subject exams. Results demonstrated the improvement of iodine\u0000quantification accuracy using ACCELERATION.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

AutOmatic floW planning for fetaL MRI (OWL) 用于羊乳核磁共振成像（OWL）的自动浮动规划

arXiv - PHYS - Medical Physics Pub Date : 2024-08-12 DOI: arxiv-2408.06326

Sara Neves Silva, Tomas Woodgate, Sarah McElroy, Michela Cleri, Kamilah St Clair, Jordina Aviles Verdera, Kelly Payette, Alena Uus, Lisa Story, David Lloyd, Mary A Rutherford, Joseph V Hajnal, Kuberan Pushparajah, Jana Hutter

{"title":"AutOmatic floW planning for fetaL MRI (OWL)","authors":"Sara Neves Silva, Tomas Woodgate, Sarah McElroy, Michela Cleri, Kamilah St Clair, Jordina Aviles Verdera, Kelly Payette, Alena Uus, Lisa Story, David Lloyd, Mary A Rutherford, Joseph V Hajnal, Kuberan Pushparajah, Jana Hutter","doi":"arxiv-2408.06326","DOIUrl":"https://doi.org/arxiv-2408.06326","url":null,"abstract":"Two subsequent deep learning networks, one localizing the fetal chest and one\u0000identifying a set of landmarks on a coronal whole-uterus balanced steady-state\u0000free precession scan, were trained on 167 and 71 fetal datasets across field\u0000strengths, acquisition parameters, and gestational ages and implemented in a\u0000real-time setup. Next, a phase-contrast sequence was modified to use the\u0000identified landmarks for planning. The OWL pipeline was evaluated\u0000retrospectively in 10 datasets and prospectively in 7 fetal subjects\u0000(gestational ages between 36+3 and 39+3 weeks). The prospective cases were\u0000additionally manually planned to enable direct comparison both qualitatively,\u0000by scoring the planning quality, and quantitatively, by comparing the indexed\u0000flow measurements. OWL enabled real-time fully automatic planning of the 2D\u0000phase-contrast scans in all but one of the prospective participants. The fetal\u0000body localization achieved an overall Dice score of 0.94+-0.05 and the cardiac\u0000landmark detection accuracy was 5.77+-2.91 mm for the descending aorta,\u00004.32+-2.44 mm for the spine, and 4.94+-3.82 mm for the umbilical vein. For the\u0000prospective cases, overall planning quality was 2.73/4 for the automated scans,\u0000compared to 3.0/4 for manual planning, and the flow quantitative evaluation\u0000showed a mean difference of -1.8% (range -14.2% to 14.9%) by comparing the\u0000indexed flow measurements obtained from gated automatic and manual\u0000acquisitions. Real-time automated planning of 2D phase-contrast MRI was\u0000effectively accomplished for 2 major vessels of the fetal vasculature. While\u0000demonstrated here on 0.55T, the achieved method has wider implications, and\u0000training across multiple field strengths enables generalization. OWL thereby\u0000presents an important step towards extending access to this modality beyond\u0000specialised centres.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Pulse excitation mode selection via AI Pipeline to Fully Automate the WUCT System 通过人工智能管道选择脉冲激励模式，实现 WUCT 系统的完全自动化

arXiv - PHYS - Medical Physics Pub Date : 2024-08-10 DOI: arxiv-2408.05401

Ankur Kumar, Mayank Goswami

{"title":"Pulse excitation mode selection via AI Pipeline to Fully Automate the WUCT System","authors":"Ankur Kumar, Mayank Goswami","doi":"arxiv-2408.05401","DOIUrl":"https://doi.org/arxiv-2408.05401","url":null,"abstract":"The parametric optimization for the ultrasound computed tomography system is\u0000introduced. It is hypothesized that the pulse characteristic directly affects\u0000the information present in the reconstructed profile. The ultrasound excitation\u0000modes based on pulse-width modifications are studied to estimate the effect on\u0000reconstruction quality. Studies show that the pulse width affects the response\u0000of the transducer and, thus, the reconstruction. The ultrasound scanning\u0000parameters, mainly pulse width, are assessed and optimally set by an Artificial\u0000Intelligence driven process, according to the object without the requirement of\u0000a-priori information. The optimization study uses a novel intelligent object\u0000placement procedure to ensure repeatability of the same region of interest, a\u0000key requirement to minimize the error. Further, Kanpur Theorem 1 is implemented\u0000to evaluate the quality of the acquired projection data and discard inferior\u0000quality data. Scanning results corresponding to homogeneous and heterogeneous\u0000phantoms are presented. The image processing step involves deep learning model\u0000evaluating the dice coefficient for estimating the reconstruction quality if\u0000prior information about the inner profile is known or a classical error\u0000estimate otherwise. The models segmentation accuracy is 95.72 percentage and\u0000intersection over union score is 0.8842 on the validation dataset. The article\u0000also provides valuable insights about the development and low-level control of\u0000the system.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ankle Exoskeletons May Hinder Standing Balance in Simple Models of Older and Younger Adults 踝关节外骨骼可能会妨碍老年人和年轻人在简单模型中的站立平衡

arXiv - PHYS - Medical Physics Pub Date : 2024-08-10 DOI: arxiv-2408.05418

Daphna Raz, Varun Joshi, Brian Umberger, Necmiye Ozay

{"title":"Ankle Exoskeletons May Hinder Standing Balance in Simple Models of Older and Younger Adults","authors":"Daphna Raz, Varun Joshi, Brian Umberger, Necmiye Ozay","doi":"arxiv-2408.05418","DOIUrl":"https://doi.org/arxiv-2408.05418","url":null,"abstract":"Humans rely on ankle torque to maintain standing balance, particularly in the\u0000presence of small to moderate perturbations. Reductions in maximum torque (MT)\u0000production and maximum rate of torque development (MRTD) occur at the ankle\u0000during aging, diminishing stability. Ankle exoskeletons are powered orthotic\u0000devices that may assist older adults by compensating for reduced muscle force\u0000and power capabilities. They may also be able to assist with ankle strategies\u0000used for balance. However, no studies have investigated their effect on balance\u0000in older adults. Here, we model the effect these devices have on stability in\u0000physics-based models of healthy young and old adults, focusing on age-related\u0000deficits such as reduced MT and MRTD. We show that an ankle exoskeleton\u0000moderately reduces feasible stability boundaries in users who have full ankle\u0000strength. For individuals with age-related deficits, there is a trade-off.\u0000While exoskeletons augment stability in portions of the phase plane, they\u0000reduce stability in others. Our results suggest that well-established control\u0000strategies must still be experimentally validated in older adults.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0