arXiv - PHYS - Medical Physics最新文献

{"title":"Full Field Transmission Tomography (FFOTT) for imaging extrachromosomal circular DNA (eccDNA) in cancer cell nuclei","authors":"Nathan Boccara, Samer Alhaddad, Viacheslav Mazlin","doi":"arxiv-2408.15736","DOIUrl":"https://doi.org/arxiv-2408.15736","url":null,"abstract":"Detecting the specificity of cancer cells to distinguish them from normal\u0000ones is an important step in the general framework of cancer diagnosis. A\u0000routine example of such diagnosis in cancerous tissues implies using microscope\u0000analysis of fixed, paraffined, and colored slices such as the H&E stain (1).\u0000Such a method, which takes place after surgery, is based on carefully analyzing\u0000the cell's size and shape. Often, this approach is performed in parallel with\u0000more modern genetic tests. Recent research has hypothesized that\u0000extrachromosomal circular DNA (eccDNA) could be considered a new hallmark of\u0000cancer (4). Thus, this research aims to check if using a simple, label-free\u0000microscope dynamic analysis performed on living cancer cells would allow\u0000efficient and simpler detection of cancer cells.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176645","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}

{"title":"Electron FLASH platform for pre-clinical research: LINAC modification, simplification of pulse control and dosimetry","authors":"Banghao ZhouBiomedical Imaging and Radiation Technology Laboratory, Lixiang GuoBiomedical Imaging and Radiation Technology Laboratory, Weiguo LuDepartment of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas, USA, Mahbubur RahmanDepartment of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas, USA, Rongxiao ZhangDepartment of Radiation Medicine, New York Medical College, Valhalla, NY, Varghese Anto ChirayathDepartment of Physics, College of Science, The University of Texas at Arlington, Arlington, TX, USA, Yang Kyun ParkDepartment of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas, USA, Strahinja StojadinovicDepartment of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas, USA, Marvin GarzaDepartment of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas, USA, Ken Kang-Hsin WangBiomedical Imaging and Radiation Technology Laboratory","doi":"arxiv-2408.15426","DOIUrl":"https://doi.org/arxiv-2408.15426","url":null,"abstract":"Background: FLASH radiotherapy is a treatment regime that delivers\u0000therapeutic dose to tumors at an ultra-high dose rate while maintaining\u0000adequate normal tissue sparing. However, a comprehensive understanding of the\u0000underlying mechanisms, potential late toxicities, and optimal fractionation\u0000schemes is important for successful clinical translation. This has necessitated\u0000extensive pre-clinical investigations, leading several research institutions to\u0000initiate dedicated FLASH research programs. Purpose: This work describes a\u0000workflow for establishing an easily accessible electron FLASH (eFLASH)\u0000platform. The platform incorporates simplified pulse control, optimized dose\u0000rate delivery, and validated Monte Carlo (MC) dose engine for accurate in vivo\u0000dosimetry dedicated to FLASH pre-clinical studies. Methods: Adjustment of the\u0000automatic frequency control (AFC) module allowed us to optimize the LINAC pulse\u0000form to achieve a uniform dose rate. A MC model for the 6 MeV FLASH beam was\u0000commissioned to ensure accurate dose calculation necessary for reproducible in\u0000vivo studies. Results: Optimizing the AFC module enabled the generation of a\u0000uniform pulse form, ensuring consistent dose per pulse and a uniform dose rate\u0000throughout FLASH irradiation. The MC model closely agreed with film\u0000measurements. MC dose calculations indicated that 6 MeV FLASH is adequate to\u0000achieve a uniform dose distribution for mouse whole brain irradiation but may\u0000not be optimal for the spinal cord study. Conclusions: We present a novel\u0000workflow for establishing a LINAC-based eFLASH research platform, incorporating\u0000techniques for optimized dose rate delivery, a simplified pulse control system,\u0000and validated MC engine. This work provides researchers with valuable new\u0000approaches to facilitate the development of robust and accessible LINAC-based\u0000system for FLASH studies.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176651","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}

{"title":"Sequential-Scanning Dual-Energy CT Imaging Using High Temporal Resolution Image Reconstruction and Error-Compensated Material Basis Image Generation","authors":"Qiaoxin Li, Ruifeng Chen, Peng Wang, Guotao Quan, Yanfeng Du, Dong Liang, Yinsheng Li","doi":"arxiv-2408.14754","DOIUrl":"https://doi.org/arxiv-2408.14754","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 DECT leveraging advanced X-ray source\u0000and/or detector technologies, the use of the sequential-scanning data\u0000acquisition scheme to implement DECT may make a broader impact on clinical\u0000practice because this scheme requires no specialized hardware designs and can\u0000be directly implemented into conventional CT systems. However, since the\u0000concentration of iodinated contrast agent in the imaged subject varies over\u0000time, sequentially scanned data sets acquired at two tube potentials are\u0000temporally inconsistent. As existing material basis image reconstruction\u0000approaches assume that the data sets acquired at two tube potentials are\u0000temporally consistent, the violation of this assumption results in inaccurate\u0000quantification of material concentration. In this work, we developed\u0000sequential-scanning DECT imaging using high temporal resolution image\u0000reconstruction and error-compensated material basis image generation,\u0000ACCELERATION in short, to address the technical challenge induced by temporal\u0000inconsistency of sequentially scanned data sets and improve quantification\u0000accuracy of material concentration in sequential-scanning DECT. ACCELERATION\u0000has been validated and evaluated using numerical simulation data sets generated\u0000from clinical human subject exams and experimental human subject studies.\u0000Results demonstrated the improvement of quantification accuracy and image\u0000quality using ACCELERATION.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176652","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}

{"title":"3Dπ: Three-Dimensional Positron Imaging, A Novel Total-Body PET Scanner Using Xenon-Doped Liquid Argon Scintillator","authors":"Azam Zabihi, Xinran Li, Alejandro Ramirez, Manuel D. Da Rocha Rolo, Davide Franco, Federico Gabriele, Cristiano Galbiati, Michela Lai, Daniel R. Marlow, Andrew Renshaw, Shawn Westerdale, Masayuki Wada","doi":"arxiv-2408.14645","DOIUrl":"https://doi.org/arxiv-2408.14645","url":null,"abstract":"Objective: This paper introduces a novel PET imaging methodology called\u00003-dimensional positron imaging (3D{pi}), which integrates total-body (TB)\u0000coverage, time-of-flight (TOF) technology, ultra-low dose imaging capabilities,\u0000and ultra-fast readout electronics inspired by emerging technology from the\u0000DarkSide collaboration. Approach: The study evaluates the performance of\u00003D{pi} using Monte Carlo simulations based on NEMA NU 2-2018 protocols. The\u0000methodology employs a homogenous, monolithic scintillator composed of liquid\u0000argon (LAr) doped with xenon (Xe) with silicon photomultipliers (SiPM)\u0000operating at cryogenic temperatures. Main results: Significant enhancements in\u0000system performance are observed, with the 3D{pi} system achieving a noise\u0000equivalent count rate (NECR) of 3.2 Mcps which is approximately two times\u0000higher than uEXPLORER's peak NECR (1.5 Mcps) at 17.3 (kBq/mL). Spatial\u0000resolution measurements show an average FWHM of 2.7 mm across both axial\u0000positions. The system exhibits superior sensitivity, with values reaching 373\u0000kcps/MBq with a line source at the center of the field of view. Additionally,\u00003D{pi} achieves a TOF resolution of 151 ps at 5.3 kBq/mL, highlighting its\u0000potential to produce high-quality images with reduced noise levels.\u0000Significance: The study underscores the potential of 3D{pi} in improving PET\u0000imaging performance, offering the potential for shorter scan times and reduced\u0000radiation exposure for patients. The Xe-doped LAr offers advantages such as\u0000fast scintillation, enhanced light yield, and cost-effectiveness. Future\u0000research will focus on optimizing system geometry and further refining\u0000reconstruction algorithms to exploit the strengths of 3D{pi} for clinical\u0000applications.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176653","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}

{"title":"Methodology of safety evaluation of In-Vessel Retention","authors":"Florian FichotIRSN/PSN-RES/SAM/LEPC, Laure CaréniniIRSN/PSN-RES/SAM/LEPC, Stephan BrummJRC, Marco SangiorgiJRC","doi":"arxiv-2408.14522","DOIUrl":"https://doi.org/arxiv-2408.14522","url":null,"abstract":"Molten corium stabilization following a severe accident is of crucial\u0000importance in order to ensure containment integrity on a long-term basis and\u0000minimizing radioactive elements releases outside the plant. Among the possible\u0000options, In-Vessel Retention (IVR) through external cooling appears as an\u0000attractive solution that would limit the dispersion of corium in the plant and\u0000minimize the risks of containment failure. Nevertheless its feasibility has to\u0000be proved.The IVR strategy is already adopted in Europe for some VVER 440 type\u0000213 reactors thanks to thorough research work started in the '90s for the\u0000Finnish Loviisa power plant, and subsequently extended to Bohunice and Mochovce\u0000(Slovakia), Dukovany (Czech Republic) and Paks (Hungary) power plants. The\u0000strategy is also included in the design of some high power new Gen.III reactors\u0000such as AP1000, APR 1400 and Chinese HPR1000 and CAP1400. It has also been\u0000studied in the past for other reactor concepts like KERENA (1250 MWe - BWR),\u0000AP600 or VVER-640.Current approaches for reactors with relatively small power,\u0000such as VVER 440 or AP600, use conservative assumptions for the safety\u0000demonstration. However, for higher power reactors (around 1000 MWe), the safety\u0000margin is reduced and it is necessary to evaluate the IVR strategy with\u0000best-estimate methods in order to reduce the uncertainties associated with the\u0000involved phenomena. Additional R&D as well as a revision of the methodology are\u0000needed to ensure and demonstrate adequate safety margins, including, in\u0000particular, best-estimate evaluations of thermal load applied on the vessel and\u0000mechanical resistance of the ablated vessel.The IVMR project (In-Vessel Melt\u0000Retention) was built with the goal of providing new knowledge (experimental,\u0000theoretical and technical) and a new methodology able to provide a\u0000best-estimate evaluation of IVR strategy for large power reactors. The main\u0000objective of Task 2.1 within WP2 was to define a common methodology to analyse\u0000IVR Severe Accident Management (SAM) strategy for the different types of EU\u0000NPPs. It started by reviewing the status of existing methodology and aimed at\u0000elaborating a more general, updated and less conservative one applicable to\u0000several types of reactors.This paper describes the proposed new methodology. It\u0000starts with the identification of the deficiencies of the standard methodology\u0000when it is applied to a high power reactor. It introduces the minimum vessel\u0000thickness as a parameter representing the cumulated imbalance between internal\u0000heat load and external cooling. Then it explains how to use that parameter in\u0000the evaluation of the safety margin. Although some examples are given as\u0000illustrations, it must be kept in mind that this paper proposes a generic\u0000methodology but there cannot be any generic conclusion: any reactor design must\u0000be evaluated independently.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176656","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}

{"title":"Patient-specific prediction of regional lung mechanics in ARDS patients with physics-based models: A validation study","authors":"Maximilian Rixner, Maximilian Ludwig, Matthias Lindner, Inéz Frerichs, Armin Sablewski, Karl-Robert Wichmann, Max-Carl Wachter, Kei W. Müller, Dirk Schädler, Wolfgang A. Wall, Jonas Biehler, Tobias Becher","doi":"arxiv-2408.14607","DOIUrl":"https://doi.org/arxiv-2408.14607","url":null,"abstract":"The choice of lung protective ventilation settings for mechanical ventilation\u0000has a considerable impact on patient outcome, yet identifying optimal\u0000ventilatory settings for individual patients remains highly challenging due to\u0000the inherent inter- and intra-patient pathophysiological variability. In this\u0000validation study, we demonstrate that physics-based computational lung models\u0000tailored to individual patients can resolve this variability, allowing us to\u0000predict the otherwise unknown local state of the pathologically affected lung\u0000during mechanical ventilation. For seven ARDS patients undergoing invasive\u0000mechanical ventilation, physics-based, patient-specific lung models were\u0000created using chest CT scans and ventilatory data. By numerically resolving the\u0000interaction of the pathological lung with the airway pressure and flow imparted\u0000by the ventilator, we predict the time-dependent and heterogeneous local state\u0000of the lung for each patient and compare it against the regional ventilation\u0000obtained from bedside monitoring using Electrical Impedance Tomography.\u0000Excellent agreement between numerical simulations and experimental data was\u0000obtained, with the model-predicted anteroposterior ventilation profile\u0000achieving a Pearson correlation of 96% with the clinical reference data. Even\u0000when considering the regional ventilation within the entire transverse chest\u0000cross-section and across the entire dynamic ventilation range, an average\u0000correlation of more than 81% and an average root mean square error of less than\u000015% were achieved. The results of this first systematic validation study\u0000demonstrate the ability of computational models to provide clinically relevant\u0000information and thereby open the door for a truly patient-specific choice of\u0000ventilator settings on the basis of both individual anatomy and\u0000pathophysiology.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176659","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}

{"title":"Multi-Modality and Temporal Analysis of Cervical Cancer Treatment Response","authors":"Haotian Feng, Emi Yoshida, Ke Sheng","doi":"arxiv-2408.13408","DOIUrl":"https://doi.org/arxiv-2408.13408","url":null,"abstract":"Cervical cancer presents a significant global health challenge, necessitating\u0000advanced diagnostic and prognostic approaches for effective treatment. This\u0000paper investigates the potential of employing multi-modal medical imaging at\u0000various treatment stages to enhance cervical cancer treatment outcomes\u0000prediction. We show that among Gray Level Co-occurrence Matrix (GLCM) features,\u0000contrast emerges as the most effective texture feature regarding prediction\u0000accuracy. Integration of multi-modal imaging and texture analysis offers a\u0000promising avenue for personalized and targeted interventions, as well as more\u0000effective management of cervical cancer. Moreover, there is potential to reduce\u0000the number of time measurements and modalities in future cervical cancer\u0000treatment. This research contributes to advancing the field of precision\u0000diagnostics by leveraging the information embedded in noninvasive medical\u0000images, contributing to improving prognostication and optimizing therapeutic\u0000strategies for individuals diagnosed with cervical cancer.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142223407","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}

{"title":"Laboratory x-ray nano-computed tomography for biomedical research","authors":"Till DreierLund University Department of Medical Radiation PhysicsExcillum AB, Robin KrügerLund University Department of Medical Radiation Physics, Gustaf BernströmLund University Department of Experimental Medical Science, Karin Tran-LundmarkLund University Department of Experimental Medical ScienceLund University Wallenberg Center for Molecular MedicineThe Pediatric Heart Center, Skåne University Hospital, Isabel GonçalvesCardiology, Skåne University Hospital, Martin BechLund University Department of Medical Radiation Physics","doi":"arxiv-2408.12336","DOIUrl":"https://doi.org/arxiv-2408.12336","url":null,"abstract":"High-resolution x-ray tomography is a common technique for biomedical\u0000research using synchrotron sources. With advancements in laboratory x-ray\u0000sources, an increasing number of experiments can be performed in the lab. In\u0000this paper, the design, implementation, and verification of a laboratory setup\u0000for x-ray nano-computed tomography is presented using a nano-focus x-ray source\u0000and high geometric magnification not requiring any optical elements. Comparing\u0000a scintillator-based detector to a photon counting detector shows a clear\u0000benefit of using photon counting detectors for these applications, where the\u0000flux of the x-ray source is limited and samples have low contrast. Sample\u0000contrast is enhanced using propagation-based phase contrast. The resolution of\u0000the system is verified using 2D resolution charts and using Fourier Ring\u0000Correlation on reconstructed CT slices. Evaluating noise and contrast\u0000highlights the benefits of photon counting detectors and the contrast\u0000improvement through phase contrast. The implemented setup is capable of\u0000reaching sub-micron resolution and satisfying contrast in biological samples,\u0000like paraffin embedded tissue.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176654","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}

{"title":"Learned Regularization for Quantitative Pulse-Echo Speed-of-Sound Imaging","authors":"Parisa Salemi YolgunluUniversity of Bern, Jules BlomUniversity of Twente, Naiara Korta MartiartuUniversity of Bern, Michael JaegerUniversity of Bern","doi":"arxiv-2408.11471","DOIUrl":"https://doi.org/arxiv-2408.11471","url":null,"abstract":"Computed ultrasound tomography in echo mode generates maps of tissue speed of\u0000sound (SoS) from the shift of echoes when detected under varying steering\u0000angles. It solves a linearized inverse problem that requires regularization to\u0000complement the echo shift data with a priori constraints. Spatial gradient\u0000regularization has been used to enforce smooth solutions, but SoS estimates\u0000were found to be biased depending on tissue layer geometry. Here, we propose to\u0000train a linear operator to minimize SoS errors on average over a large number\u0000of random tissue models that sample the distribution of geometries and SoS\u0000values expected in vivo. In an extensive simulation study on liver imaging, we\u0000demonstrate that biases are strongly reduced, with residual biases being the\u0000result of a partial non-linearity in the actual physical problem. This approach\u0000can either be applied directly to echo-shift data or to the SoS maps estimated\u0000with gradient regularization, where the former shows slightly better\u0000performance, but the latter is computationally more efficient. Experimental\u0000phantom results confirm the transferability of our results to real ultrasound\u0000data.","PeriodicalId":501378,"journal":{"name":"arXiv - PHYS - Medical Physics","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142176655","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}

{"title":"Orientation independent quantification of macromolecular proton fraction in tissues with suppression of residual dipolar coupling","authors":"Zijian Gao, Ziqiang Yu, Ziqin Zhou, Jian Hou, Baiyan Jiang, Michael Ong, Weitian Chen","doi":"arxiv-2408.09733","DOIUrl":"https://doi.org/arxiv-2408.09733","url":null,"abstract":"Quantitative magnetization transfer (MT) imaging enables non-invasive\u0000characterization of the macromolecular environment of tissues. However, recent\u0000work has highlighted that the quantification of MT parameters exhibits\u0000orientation dependence in ordered tissue structures, potentially confounding\u0000its clinical applications. Notably, in tissues with ordered structures, such as\u0000articular cartilage and myelin, the residual dipolar coupling (RDC) effect can\u0000arise owing to incomplete averaging of dipolar-dipolar interactions of water\u0000protons. In this study, we demonstrated the confounding effect of RDC on\u0000quantitative MT imaging in ordered tissues can be suppressed by using an\u0000emerging technique known as macromolecular proton fraction mapping based on\u0000spin-lock (MPF-SL). The off-resonance spin-lock pulse in MPF-SL could be\u0000designed to generate a strong effective spin-lock field to suppress RDC without\u0000violating the specific absorption rate and hardware limitations in clinical\u0000scans. Furthermore, removing the water signal in MPF-SL enabled the application\u0000of a strong effective spin-lock field without any confounding signal from\u0000direct water saturation. Our findings were experimentally validated using human\u0000knee specimens and healthy human cartilage. The results demonstrated that\u0000MPF-SL exhibits lower sensitivity to tissue orientation compared with R2,\u0000R1rho, and saturation-pulse-based MT imaging. Thus, MPF-SL could serve as a\u0000valuable orientation-independent technique for quantifying MPF.","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":"142176658","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}