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Current landscape and potential future applications of artificial intelligence in medical physics and radiotherapy
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作者 Wing-Yan Ip Fu-Ki Yeung +3 位作者 Shang-Peng Felix Yung Hong-Cheung Jeffrey Yu Tsz-Him So Varut Vardhanabhuti 《Artificial Intelligence in Medical Imaging》 2021年第2期37-55,共19页
Artificial intelligence(AI)has seen tremendous growth over the past decade and stands to disrupts the medical industry.In medicine,this has been applied in medical imaging and other digitised medical disciplines,but i... Artificial intelligence(AI)has seen tremendous growth over the past decade and stands to disrupts the medical industry.In medicine,this has been applied in medical imaging and other digitised medical disciplines,but in more traditional fields like medical physics,the adoption of AI is still at an early stage.Though AI is anticipated to be better than human in certain tasks,with the rapid growth of AI,there is increasing concerns for its usage.The focus of this paper is on the current landscape and potential future applications of artificial intelligence in medical physics and radiotherapy.Topics on AI for image acquisition,image segmentation,treatment delivery,quality assurance and outcome prediction will be explored as well as the interaction between human and AI.This will give insights into how we should approach and use the technology for enhancing the quality of clinical practice. 展开更多
关键词 Artificial intelligence Medical physics RADIOTHERAPY Image acquisition Image segmentation Treatment planning Treatment delivery Quality assurance
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Radiation Shielding Analysis and Design of tof PET-CT Facility at Institute of Nuclear Medical Physics under Bangladesh Atomic Energy Commission, Bangladesh
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作者 M. F. Uddin R. Khatun +7 位作者 S. Akter H. M. Jamil A. N. Monika M. A. Rahaman R. P. Das R. A. Sharmin M. M. Rahman M. M. Ahasan 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2019年第1期1-8,共8页
High resolution (4 mm) tof PET-CT (positron emission tomography-computed tomography) from Philips of model Ingenuity TF is newly installed at Institute of Nuclear Medical Physics (INMP). 128 slice CT component incorpo... High resolution (4 mm) tof PET-CT (positron emission tomography-computed tomography) from Philips of model Ingenuity TF is newly installed at Institute of Nuclear Medical Physics (INMP). 128 slice CT component incorporated with PET provides comparatively lower dose than the 511 keV annihilation photons associated with positron decay from PET scan. So, for designing shielding in our PET-CT facility, only 511 keV annihilation photons energy has been considered. The main objective of this paper is to show what measures have been taken to protect patients, occupational workers as well as environment from PET-CT radiation hazard through a cost effective design that satisfy the national regulatory demand. In this paper, AAPM (American Associations of Physicists in Medicine) Task group 108 analysis for PET and PET-CT shielding requirements is followed for our PET-CT facility shielding design. From theoretical calculation as shielding requirement, 1.1 cm Pb thickness or, 13 cm concrete thicknesses are found. Practically, all walls and ceiling are of 30.48 cm (1 foot) thick made of concrete with density 2.35 gcm-3 for more safety. As x-ray from CT is not taken into account for shielding analysis, Bangladesh Atomic Energy Commission (BAEC) conducted an extensive radiation survey at controlled, supervised and public area for CT. The report that is found meets the national regulatory requirements. 展开更多
关键词 Radiation Protection PET-CT SHIELDING FDG
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Erratum to “Novel Wavelet-Based Segmentation of Prostate CBCT Images with Implanted Calypso Transponders” [International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 6 (2017) 336-343]
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作者 Yingxia Liu Ziad Saleh +5 位作者 Yulin Song Maria Chan Xiang Li Chengyu Shi Xin Qian Xiaoli Tang 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2017年第4期376-376,共1页
The original online version of this article (Liu, Y.X., Saleh, Z., Song, Y.L., Chan, M., Li, X., Shi, C.Y., Qian, X. and Tang, X.L (2017) Novel Wavelet-Based Segmentation of Prostate CBCT Images with Implanted Calypso... The original online version of this article (Liu, Y.X., Saleh, Z., Song, Y.L., Chan, M., Li, X., Shi, C.Y., Qian, X. and Tang, X.L (2017) Novel Wavelet-Based Segmentation of Prostate CBCT Images with Implanted Calypso Transponders. International Journal of Medical Physics, Clinical Engineering and Radiation Oncology, 6, 336-343. doi: 10.4236/ijmpcero.2017.63030) was published without acknowledging our support. The authors wish to add the acknowledgments. 展开更多
关键词 Erratum
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A Study of the TPS Based Beam-Matching Concept for Medical Linear Accelerators at a Tertiary Hospital
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作者 Ntombela N. Lethukuthula Rovetto J. Nicolas +1 位作者 Nethwadzi C. Lutendo Mpumelelo Nyathi 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2024年第1期16-25,共10页
The flexibility in radiotherapy can be improved if patients can be moved between any one of the department’s medical linear accelerators (LINACs) without the need to change anything in the patient’s treatment plan. ... The flexibility in radiotherapy can be improved if patients can be moved between any one of the department’s medical linear accelerators (LINACs) without the need to change anything in the patient’s treatment plan. For this to be possible, the dosimetric characteristics of the various accelerators must be the same, or nearly the same. The purpose of this work is to describe further and compare measurements and parameters after the initial vendor-recommended beam matching of the five LINACs. Deviations related to dose calculations and to beam matched accelerators may compromise treatment accuracy. The safest and most practical way to ensure that all accelerators are within clinical acceptable accuracy is to include TPS calculations in the LINACs matching evaluation. Treatment planning system (TPS) was used to create three photons plans with different field sizes 3 × 3 cm, 10 × 10 cm and 25 × 25 cm at a depth of 4.5 cm in Perspex. Calculated TPS plans were sent to Mosaiq to be delivered by five LINACs. TPS plans were compared with five LINACs measurements data using Gamma analyses of 2% and 2 mm. The results suggest that for four out of the five LINACs, there was generally good agreement, less than a 2% deviation between the planned dose distribution and the measured dose distribution. However, one specific LINAC named “Asterix” exhibited a deviation of 2.121% from the planned dose. The results show that all of the LINACs’ performance were within the acceptable deviation and delivering radiation dose consistently and accurately. 展开更多
关键词 RADIOTHERAPY Beam-Matching Linear Accelerator DOSIMETRY
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In Vivo Research of Time-Lapse Changes on Surgical Sutures by OCT Signal Analysis
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作者 Fengcheng Wei Hinata Nakakubo +1 位作者 Nene Amishiro Masato Ohmi 《Optics and Photonics Journal》 2025年第1期1-8,共8页
Currently, animal and clinical research on biomaterials, such as surgical sutures, are mainly performed by removing them from the experiment targets and observing them by microscopy. However, traditional microscopy is... Currently, animal and clinical research on biomaterials, such as surgical sutures, are mainly performed by removing them from the experiment targets and observing them by microscopy. However, traditional microscopy is not able to observe the internal structure, and there is a risk of sacrificing animals to remove the suture and damaging the materials. Therefore, we introduced optical coherence tomography (OCT) to observe and evaluate four different kinds of surgical sutures in vivo (monofilament absorbable and nonabsorbable sutures and braided absorbable and nonabsorbable sutures). As a result, while the monofilament nonabsorbable sutures showed almost no change over time, the absorbable sutures had color fading and it was also confirmed that the internal structure became chaotic due to decomposition, which improved the OCT signal intensity. For the braided sutures, both absorbable and nonabsorbable, we found that the reflection signal improved from week 0 because blood got among the filaments of sutures and dried during recovery which increased OCT signal from week 0 to week 1. We also confirmed that the braided sutures untwisted over time. All four kinds of sutures were pulled due to the movement of rats during recovery. It is expected that OCT technology will be of great help in in vivo experiments on biomaterials such as sutures. 展开更多
关键词 Optical Coherence Tomography Surgical Suture Biomedical PLA/PCL PVDF PGA PES In Vivo Animal Experiment
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Comparison of corneal aberrations from anterior segment swept source OCT versus Placido-topography combined spectral domain OCT in cataract patients
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作者 Stefan Georgiev Manuel Ruiss +2 位作者 Andreea Dana-Fisus Rainer ALeitgeb Oliver Find 《Eye and Vision》 2025年第5期1-11,共11页
Background To comprehensively evaluate the agreement of component corneal aberrations from the newly updated wavefront analysis software of a swept-source optical coherence tomographer(SS-OcT)and a referential Placido... Background To comprehensively evaluate the agreement of component corneal aberrations from the newly updated wavefront analysis software of a swept-source optical coherence tomographer(SS-OcT)and a referential Placido-topography combined OcT device in elderly cataract patients.Methods Retrospective study including 103 eyes from 103 elderly patients scheduled for cataract surgery that were measured on the same day with a SS-OcT(Heidelberg Engineering,Germany)device and a Placido-topography combined OCT device(CsO,Italy).Anterior,total,and posterior corneal wavefront aberrations were evaluated for their mean differences and limits of agreement(LoA)via Bland-Altman plots.Vector analysis was additionally employed to compare corneal astigmatism measurements in dioptric vector space.Results Mean differences of all corneal aberrometric parameters did not exceed O.05 um.Total corneal aberrations were not significantly different from 0 except for vertical coma(-0.04μm;P=0.003),spherical aberration(-0.01μm,P<0.001),and root mean square(RMS)higher-order aberration(HOA)(0.03μm,P=0.04).The 95%LoA for total corneal aberration parameters between both devices were-0.46 to 0.42μm for horizontal astigmatism,-0.37 to 0.41μm for oblique astigmatism,-0.19 to 0.17μm for oblique trefoil,-0.33 to 0.25μm for vertical coma,-0.20 to 0.22μm for horizontal coma,-0.22 to 0.20 um for horizontal trefoil,-0.11 to 0.08μm for spherical aberration,and-0.22 to 0.28 um for RMs HOA.Vector analysis revealed no statistically significant mean differences for anterior,total,and posterior corneal astigmatism in dioptric vector space.Conclusion In eyes undergoing cataract surgery with a regular elderly cornea,corneal wavefront analysis from the SS-OcT device showed functional equivalency to the reference device.Nevertheless,clinically relevant higher-order aberration parameters should be interpreted with caution for surgical decision-making. 展开更多
关键词 CORNEAL ABERRATIONS WAVEFRONT analysis Optical coherence tomography CATARACT surgery
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In vivo 3D dose distribution verification for lung cancer:from rigid-body model to porcine lung
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作者 Yutao Zhang Kai Xie +9 位作者 Lintao Song Jiewei Lai Haiping Zheng Qianjia Huang Hao Wang Tao Lin Liugang Gao Jiawei Sun Jianrong Dai Xinye Ni 《Bio-Design and Manufacturing》 2025年第6期994-1008,I0032,共16页
This study introduces a novel concept,biological in vivo three-dimensional(3D)dose distribution verification,aimed at investigating how respiratory motion affects the efficacy of lung cancer radiotherapy,representing ... This study introduces a novel concept,biological in vivo three-dimensional(3D)dose distribution verification,aimed at investigating how respiratory motion affects the efficacy of lung cancer radiotherapy,representing an evolution from the current standard of rigid-body dose distribution verification.A 3D ex vivo biological lung motion simulation device(3D-BioLungEx)was designed to replicate human respiration.A radiotherapy plan of the patient was copied to the porcine lung,which was driven by 3D-BioLungEx to simulate various respiratory patterns that occur during treatment.To ensure anatomical consistency with the patient’s lung structure,during transmission,skin,skeleton,and organs were adjusted according to CT images of the porcine lung.The patient’s radiotherapy plan was then adapted to the porcine lung using the Monaco treatment planning system(TPS).Next,an iterative optimization and scatter inversion-based dose distribution retro-analysis algorithm(IOSI-BLDose)was developed to calculate the dose distribution during treatment.Gamma passing rates were used to quantify discrepancies between this dose distribution and that of the radiotherapy plan.When respiratory conditions were replicated,the passing rate reached up to 93.61%,while irregular breathing dropped it to 70%-90%,primarily due to amplitude changes.However,cycle variations had minimal impact.Compared to conventional rigid-body dose distribution verification,our method provides real-time biological feedback and more effectively captures motion-induced deviations.Accordingly,our biological in vivo 3D dose distribution verification has potential for improving treatment precision and enabling adaptive radiotherapy in clinical practice. 展开更多
关键词 Biological lung 3D printing Motion simulation device RADIOTHERAPY Lung cancer Dose distribution verification
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Novel Classification Scheme for Early Alzheimer's Disease(AD)Severity Diagnosis Using Deep Features of the Hybrid Cascade Attention Architecture:Early Detection of AD on MRI Scans
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作者 Mohamadreza Khosravi Hossein Parsaei Khosro Rezaee 《Tsinghua Science and Technology》 2025年第6期2572-2591,共20页
In neuropathological diseases such as Alzheimer's Disease(AD),neuroimaging and Magnetic Resonance Imaging(MRI)play crucial roles in the realm of Artificial Intelligence of Medical Things(AIoMT)by leveraging edge i... In neuropathological diseases such as Alzheimer's Disease(AD),neuroimaging and Magnetic Resonance Imaging(MRI)play crucial roles in the realm of Artificial Intelligence of Medical Things(AIoMT)by leveraging edge intelligence resources.However,accurately classifying MRI scans based on neurodegenerative diseases faces challenges due to significant variability across classes and limited intra-class differences.To address this challenge,we propose a novel approach aimed at improving the early detection of AD through MRI imaging.This method integrates a Convolutional Neural Network(CNN)with a Cascade Attention Model(CAM-CNN).The CAM-CNN model outperforms traditional CNNs in AD classification accuracy and processing complexity.In this architecture,the attention mechanism is effectively implemented by utilizing two constraint cost functions and a cross-network with diverse pre-trained parameters for a two-stream architecture.Additionally,two new cost functions,Satisfied Rank Loss(SRL)and Cross-Network Similarity Loss(CNSL),are introduced to enhance collaboration and overall network performance.Finally,a unique entropy addition method is employed in the attention module for network integration,converting intermediate outcomes into the final prediction.These components are designed to work collaboratively and can be sequentially trained for optimal performance,thereby enhancing the effectiveness of AD stage classification and robustness to interference from MR images.Validation using the Kaggle dataset demonstrates the model's accuracy of 99.07%in multiclass classification,ensuring precise classification and early detection of all AD subtypes.Further validation across three feature categories with varying numbers confirms the robustness of the proposed approach,with deviations from the standard criteria of less than 1%.Applied in Alzheimer's patient care,this capability holds promise for enhancing value-based therapy and clinical decision-making.It aids in differentiating Alzheimer's patients from healthy individuals,thereby improving patient care and enabling more targeted therapies. 展开更多
关键词 Alzheimer's Disease(AD) Cascade Attention Model(CAM) Magnetic Resonance Imaging(MRI)Convolutional Neural Network(CNN) edge computing
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Intra-individual variability of the human seminal plasma metabolome
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作者 Janet Blaurock Sonja Grunewald Kathrin M Engel 《Asian Journal of Andrology》 2025年第5期586-591,共6页
In contrast to the conventional spermiogram, metabolomics approaches give insights into the molecular composition of semen and mayprovide more detailed information on the fertility status of the respective donor. Give... In contrast to the conventional spermiogram, metabolomics approaches give insights into the molecular composition of semen and mayprovide more detailed information on the fertility status of the respective donor. Given the intra-individual variability of spermiogramparameters between two donations, this study sought to elucidate the biological variability of the seminal plasma metabolome overan average period of 8 weeks. Two time-shifted semen samples from 15 healthy donors were compared by a targeted metabolomicsapproach utilizing the Biocrates AbsoluteIDQ p180 kit. Next to intraclass correlation coefficients (ICC), which represent a measureof reliability, coefficients of variation within individuals(CVW) and coefficients of variation between individuals (CVB) were calculatedfor each metabolite to demonstrate its stability. Furthermore, men were divided into two cohorts, a similar sperm concentration(SSC) and a differing sperm concentration (DSC) cohort, based on the observed variance in sperm concentration between the twosemen donations. The ICC was higher in the SSC compared to the DSC cohort. The levels of 18 metabolites, primarily acylcarnitines,varied between the initial and subsequent donations. After subdivision into subgroups, only ornithine and phosphatidylcholine 40:5exhibited differential levels between the two donations in the SSC group, compared to 14 metabolites in the DSCgroup.CVBwashigher than CVW but both differed between the metabolite subclasses. Biogenic amines were identified as the least reliable analytesover time, exhibiting the highest CVW,compared to sphingomyelins, which demonstrated the highest reliability with the lowestvariation.CVB was the highest for ether-bound glycerophosphatidylcholines and the lowest for amino acids. 展开更多
关键词 ACYLCARNITINES biogenic amines mass spectrometry metabolomics SEMEN seminal plasma
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Heavy Atom Effect on the Luminescent Properties of Multi-resonance Thermally Activated Delayed Fluorescence Emitters:Theoretical Insights
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作者 Rui Li Zhimin Wu +6 位作者 Xiaofang Li Xiaofei Wang Yuzhi Song Jianzhong Fan Guangping Zhang Chuan-Kui Wang Lili Lin 《Chinese Journal of Chemical Physics》 2025年第3期334-346,I0048-I0060,I0109,共27页
Multi-resonance thermally ac-tivated delayed fluorescence(MR-TADF)emitters are one of the most excellent materi-als for high performance or-ganic light-emitting diodes(OLEDs)with high color puri-ty benefiting from the... Multi-resonance thermally ac-tivated delayed fluorescence(MR-TADF)emitters are one of the most excellent materi-als for high performance or-ganic light-emitting diodes(OLEDs)with high color puri-ty benefiting from their nar-row full width at half maxi-mum(FWHM)and great de-vice performance.However,small spin-orbit coupling(SOC)is one of drawbacks for MR-TADF emitters and introduction of heavy atoms may be one effective solution.In this work,four MR-TADF molecules with different atoms(O,S,Se)are carried out based on the first-principles calculation,and excited state dynamics in both toluene and solid phase is investi-gated.Our calculation results indicate that heavy atoms could induce smaller adiabatic ener-gy gap and larger SOC between the first singlet excited state and the first triplet excited state,which is advantageous for the conversion of singlet and triplet excitons,and thus the generation of thermally activated delayed fluorescence(TADF).Though the reorganization energy and full width at half maximum(FWHM)of emission are increased,the influence is quite limited.Besides,the fluorescent rates are also little influenced.Our calculation results indicate that heavy atom introduction is an efficient strategy to enhance the SOC values of MR-TADF emitters without influencing other properties significantly. 展开更多
关键词 Organic light-emitting diodes Thermally activated delayed fluorescence Heavy atoms effect Spin-orbit coupling
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Quality Control and Optimization of Computed Tomography Dose Index Volume (CTDIvol) of LightSpeed RT16 Xtra CT Scanner
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作者 Umme Sadia Binte Kashem Shirin Akter +4 位作者 Afroza Shelley Rajada Khatun Ashrafun Nahar Monika Laila Sharmin Md. Anwarul Islam 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2025年第1期1-13,共13页
Dose estimation and quality control in computed tomography (CT) scanners are useful in controlling the dose of radiation given to patients while tests are carried out. The study was performed in a 16-slice Computed To... Dose estimation and quality control in computed tomography (CT) scanners are useful in controlling the dose of radiation given to patients while tests are carried out. The study was performed in a 16-slice Computed Tomography (CT) system of LightSpeed RT16 Xtra CT scanner. Quality control was done using a vendor-provided QA Phantom, and the six aspects of image quality were measured. For CT dosimetry, Computed Tomography Dose index volume (CTDIvol) was performed using Computed Tomography Dose Index (CTDI) Phantom. CTDI Phantom consists of three parts: Pediatric Head, Adult Head, and Adult Body Phantom. A 10 cm long pencil ion chamber DCT-10 was used to measure the dose at different positions inside the CTDI Phantom. Data were collected using MagicMax Universal software. For dose estimation of the CTDIvol Report of AAPM Task Group, 96 and 111 formalisms were used. For Pediatric Head, Adult Head, and Adult Body Phantom the measured CIDIvol was 61.04 mGy, 48.11 mGy, and 18.08 mGy respectively. The study has shown deviations of 7%, 15%, and 19% between estimated and console-displayed doses for Pediatric Head, Adult Head, and Adult Body scan techniques respectively. The six aspects of image quality measured by QA Phantom were found to be compatible with the specifications of the machine and CTDIvol measured by CTDI Phantom were found within a tolerance limit of ±20%. Hence, the QC and dosimetry of the mentioned machine are within the limit. 展开更多
关键词 Quality Control CTDIvol LightSpeed RT16 Xtra CT Scanner PHANTOM
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Effect of side group on mechanically induced conductance switching in 4,40-dipyridyl-based single-molecule junctions
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作者 Zhen Wan Chang-Feng Zheng +5 位作者 Lin Liu Yun-Long Ge Guang-Ping Zhang Shuai Qiu Hui Wang Zong-Liang Li 《Chinese Physics B》 2025年第8期678-684,共7页
The forming processes of 4,40-dipyridyl-based single-molecule junctions and mechanically induced conductance switching as well as the side-group effects are systematically investigated by applying the ab initio-based ... The forming processes of 4,40-dipyridyl-based single-molecule junctions and mechanically induced conductance switching as well as the side-group effects are systematically investigated by applying the ab initio-based adiabatic geometric optimization method and the one-dimensional transmission combined with three-dimensional correction approximation(OTCTCA)method.The numerical results show that for the 4,40-dipyridyl with a p-conjugated phenyl-phosphoryl or diphenylsilyl side group,the pyridyl vertically anchors on the second atomic layer of the pyramid-shaped Au tip electrode at small inter-electrode distances by laterally pushing the apical Au atom aside,which induces stronger pyridyl-electrode coupling and high-conductance state of the formed junctions.As the inter-electrode distance increases,the pyridyl shifts to the apical Au atom of the tip electrode.This apical Au atom introduces additional scatterings to the tunneling electrons and significantly decreases the conductance of the junctions.Furthermore,for the 4,40-dipyridyl with a phenyl-phosphoryl side group,the probability of manifesting the high-conductance state is decreased due to the oxygen atom reducing the probability of the pyridyl adsorbing on the second layer of Au tip electrode.In contrast,for the 4,40-dipyridyl with a nonconjugated cyclohexyl-phosphoryl side group,the steric hindrance from the bulky cyclohexyl group leads the molecule to preferentially form the O-Au contact,which prevents both the high conductance and mechanically induced conductance switching of the junction.Our results provide a theoretical understanding of the side-group effects on electronic transport properties of single-molecule junctions,offering an alternative explanation for the experimental observations. 展开更多
关键词 single-molecule junction electron transport properties conductance switching side-group effects
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Advances in Radiation/Photon therapy technology for the treatment of brain metastases
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作者 Hui Wang Jing Chu +5 位作者 Yao Ren Wenfan Deng Lidan Zhang Lijuan Shen Yu Kuang Lixia Xu 《Journal of Innovative Optical Health Sciences》 2025年第4期63-87,共25页
With advancements in systemic therapy,the incidence of brain metastases(BMs)continues to rise,leading to severe neurological complications.Effective and precise treatment modalities are,therefore,critically important ... With advancements in systemic therapy,the incidence of brain metastases(BMs)continues to rise,leading to severe neurological complications.Effective and precise treatment modalities are,therefore,critically important for managing BMs.Radiation therapy(RT),including photon therapy,has been essential in managing BMs.Recent technological advances have significantly enhanced the precision,efficacy,and safety of these treatments.This comprehensive review provides an in-depth examination of the latest advancements in radiation and photon therapy technologies for treating BMs,focusing on innovations such as stereotactic radiosurgery(SRS),whole-brain radiation therapy(WBRT),laser interstitial thermal therapy(LITT),and other radiation-related treatment modalities.Additionally,we discuss clinical outcomes,challenges,and future directions in this rapidly evolving field.While a detailed comparison of techniques is beyond the scope of this paper,this paper provides up-to-date technical information for physicians,medical physicists,patients,and researchers in related fields,potentially enhancing clinical outcomes.Among the treatment modalities,SRS has become a cornerstone of RT for BMs,with its implementation spanning multiple modalities over the past few decades.Given its inherent minimally invasive nature and growing clinical acceptance,SRS is positioned to further evolve as a key therapeutic tool in both neurosurgery and radiotherapy. 展开更多
关键词 Brain metastases radiation therapy stereotactic radiosurgery laser interstitial thermal therapy
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Clinical implementation of a rotating pod for lung tumor in fixed ion beamlines
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作者 Jia-Yao Sun Wen-Xuan Yang +7 位作者 Ya-Qi Li Jian Chen Jing-Fang Mao Ning-Yi Ma Yin-Xiang-Zi Sheng Wei-Wei Wang Dan You Kai-Liang Wu 《Nuclear Science and Techniques》 2025年第7期44-52,共9页
The purpose of this study was to evaluate the clinical application of a rotating pod and assess its dosimetric considerations,positional accuracy,and anatomical structure stability.A pre-dosimetric study conducted on ... The purpose of this study was to evaluate the clinical application of a rotating pod and assess its dosimetric considerations,positional accuracy,and anatomical structure stability.A pre-dosimetric study conducted on 11 patients revealed the potential for lung dose reduction using the rotational pod.Subsequently,seven patients underwent treatment with the rotational pod,and the target coverage and organs at risk doses were compared with those of conventional methods.The positional accuracy of the rotational pod,in collaboration with the imaging guidance system,was analyzed.The Dice similarity coefficient(DSC)was used to assess the settlement of tumors,trachea,and thoracic vertebrae after rotation for 20 min.In the pre-dosimetric study,there was no statistically significant difference in the volume of the internal gross tumor volume receiving≥99%of the prescription dose between the pod and conventional couch plans.However,compared to conventional couch plans,pod plans demonstrated a significant reduction in the average lung dose by 5-53%(p<0.01).Patient accrual,comprising seven cases,revealed reduced lung doses(9-26%)in four patients.For the other three patients,although there was no significant reduction in the lung dose,the use of the 90°beamline contributed to a decrease in the patient admission waiting time.The positional errors between the beams for lateral,longitudinal,vertical,ISO,pitch,and roll directions were 0.0 mm±5.3 mm,-1.2 mm±2.3 mm,-1.1 mm±2.7 mm,0.0°±0.6°,-0.1°±0.5°,and 0.0°±0.8°,respectively.The DSC for the target region and thoracic vertebrae between CT images captured before and after a 20-min rotation was higher than 0.85,whereas the DSC for the trachea was approximately 0.8.The preliminary clinical application of the rotational pod for lung tumors in fixed ion beamlines shows promise for achieving target coverage,reducing lung dose,and maintaining position accuracy. 展开更多
关键词 Rotational pod Carbon-ion radiotherapy Lung cancer Position accuracy
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Impaired Magnetic Resonance Myocardial Strain in Unoperated Ebstein’s Anomaly Is Associated with Reduced Exercise Capacity
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作者 Ahmed M.Dardeer Victoria M.Stoll +6 位作者 Boyang Liu William E.Moody Colin D.Chue Paul Clift Roman Wesolowski Lucy E.Hudsmith Richard P.Steeds 《Congenital Heart Disease》 2025年第1期27-39,共13页
Background:Patients with unrepaired Ebstein’s anomaly experience exercise intolerance,heart failure and premature mortality.Volumetric assessment of right ventricular function is difffcult due to the complex anatomy ... Background:Patients with unrepaired Ebstein’s anomaly experience exercise intolerance,heart failure and premature mortality.Volumetric assessment of right ventricular function is difffcult due to the complex anatomy of the right ventricle and tricuspid valve.Myocardial deformation indices are an early marker in other cardiac pathologies of ventricular dysfunction.Objectives:1.Assess myocardial deformation in unrepaired Ebstein’s compared to healthy controls.2.Investigate the relationships between myocardial deformation and exercise capacity.Methods:Myocardial deformation parameters(strain)were calculated using feature tracking from standard cardiac magnetic resonance cine images.Cardiopulmonary exercise results were included where available.Results:36 patients with unrepaired Ebstein’s and 36 matched controls were included.Right ventricular,right atrial,and left ventricular global longitudinal,as well as left ventricular circumferential strain were impaired in Ebstein’s patients compared to controls(p<0.05).In Ebstein’s patients right atrial peak strain correlated with their percentage predicted VO_(2) max(r=−0.448,p=0.022)and VE/VCO_(2) slope(r=0.435,p=0.026).There were no correlations between right ventricular ejection fraction and exercise parameters.When Ebstein’s patients were divided by severity into mild or severe according to the median total right/left index,those with severe demonstrated signiffcantly impaired right ventricular global longitudinal strain compared to those in the mild category(−17.5±5.4%vs.−21.4±4.4%,p=0.0017).Conclusions:Myocardial deformation parameters for both the right and left ventricle are impaired in patients with unrepaired Ebstein’s compared to healthy controls.Right atrial peak strain is related to impaired exercise capacity and warrants further investigation as an early prognostic marker in this patient cohort. 展开更多
关键词 Ebstein’s anomaly myocardial strain exercise intolerance
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Haematology results,inflammatory haematological ratios,and inflammatory indices in cervical cancer:How is the difference between cancer stage?
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作者 Phey Liana Hanif Gusneri Syahbiran +4 位作者 Nurmalia Purnama Sari Kemas Yakub Rahadiyanto Raissa Nurwany Wahyudi Nurhidayat Tungki Pratama Umar 《World Journal of Experimental Medicine》 2025年第1期80-87,共8页
BACKGROUND Cervical cancer is a prevalent form of cancer affecting women worldwide and it is the second most common cancer among women in Indonesia,accounting for 8.5%of all cancer-related deaths.Cervical cancer progr... BACKGROUND Cervical cancer is a prevalent form of cancer affecting women worldwide and it is the second most common cancer among women in Indonesia,accounting for 8.5%of all cancer-related deaths.Cervical cancer progression can be evaluated through laboratory tests to detect anaemia,an increased platelet count,and elevated inflammatory markers,therefore,effective laboratory examination is crucial for early detection and treatment of cervical cancer.AIM To evaluate the association between laboratory findings(haematology,haematology index,and inflammatory index)and the clinical stage of cervical cancer.METHODS This cross-sectional study analyzed adult cervical cancer patients’data from medical records and laboratory results including sociodemographic status,histopathological finding,clinical stage,and complete haematology examination.Numerical data was analyzed by the one-way ANOVA(normal data distribution),while the Kruskal-Wallis test was used for non-parametric data(abnormal distribution),followed by appropriate post-hoc analysis.The categorical data was analyzed by the Chi-square or Fisher Exact tests.The significance level was established at a P value<0.05.RESULTS This study involved the data of 208 adult cervical cancer patients and found no association between age,marital history,parity history,hormonal contraceptive use and cervical cancer stages.There were significant differences in the clinical laboratory test results based on the clinical stage of cervical cancer,including haemoglobin levels(P<0.001),leucocytes(P<0.001),neutrophils(P<0.001),monocytes(P=0.002),lymphocytes(P=0.006),platelets(P<0.001),neutrophil-lymphocyte ratio/NLR(P<0.001),lymphocyte-monocyte ratio/LMR(P<0.001),and plateletlymphocyte ratio/PLR(P<0.001).There were also significant differences in the systemic inflammatory index(SII)and systematic inflammatory response index(SIRI)between stage III+IV cervical cancer and stage II(SII P<0.001;SIRI P=0.001)and stage I(SII P<0.001;SIRI P=0.016),associated with the shifts in previously mentioned complete haematological values with cancer advancement.CONCLUSION The haematological parameters,inflammatory haematological ratios,and inflammatory indices exhibited significant differences between cervical cancer stages,therefore these tests can be utilized to evaluate cervical cancer progression. 展开更多
关键词 Cervical cancer HAEMATOLOGY Haematology index INFLAMMATION MALIGNANCY
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Recent biomedical advances enabled by HaloTag technology 被引量:2
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作者 WEIYU CHEN MUHSIN HYOUNIS +1 位作者 ZHONGKUO ZHAO WEIBO CAI 《BIOCELL》 SCIE 2022年第8期1789-1801,共13页
The knowledge of interactions among functional proteins helps researchers understand disease mechanisms and design potential strategies for treatment.As a general approach,the fluorescent and affinity tags were employ... The knowledge of interactions among functional proteins helps researchers understand disease mechanisms and design potential strategies for treatment.As a general approach,the fluorescent and affinity tags were employed for exploring this field by labeling the Protein of Interest(POI).However,the autofluorescence and weak binding strength significantly reduce the accuracy and specificity of these tags.Conversely,HaloTag,a novel self-labeling enzyme(SLE)tag,could quickly form a covalent bond with its ligand,enabling fast and specific labeling of POI.These desirable features greatly increase the accuracy and specificity,making the HaloTag a valuable system for various applications ranging from imaging to immobilization of POI.Notably,the HaloTag technique has already been successfully employed in a series of studies with excellent efficiency.In this review,we summarize the development of HaloTag and recent advanced investigations associated with HaloTag,including in vitro imaging(e.g.,POI imaging,cellular condition monitoring,microorganism imaging,system development),in vivo imaging,biomolecule immobilization(e.g.,POI collection,protein/nuclear acid interaction and protein structure analysis),targeted degradation(e.g.,L-AdPROM),and more.We also present a systematic discussion regarding the future direction and challenges of the HaloTag technique. 展开更多
关键词 HALOTAG Site-specific labeling Biomolecule interaction Molecular imaging Positron emission tomography
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Patient dose from radiographic rejects/repeats in radiology centers of Urmia University of Medical Sciences, Iran
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作者 Nasrollah Jabbari Ahad Zeinali Leili Rahmatnezhad 《Health》 2012年第2期94-100,共7页
Medical diagnostic X-rays are the largest manmade source of ionizing radiation received by the members of the general public. The aim of this study was to evaluate the radiographic reject/repeat rate and also to deter... Medical diagnostic X-rays are the largest manmade source of ionizing radiation received by the members of the general public. The aim of this study was to evaluate the radiographic reject/repeat rate and also to determine dose to the patients from radiographic rejects/repeats in radiology centers of Urmia University of Medical Sciences. During a 4 month period the most frequently examinations were chosen in three radiology centers. A form was designed as a reject/repeat analysis form for radiographers to complete each time a film was rejected by radiologists or repeated. The collected data were compiled at the end of each week and entered into a computer for analysis at the end of study. The results of this study showed that highest and lowest repetition rates were for pelvis, 14.01% and upper limb, 4.17%, respectively. The main reasons of repetition of radiographs were due to exposure (54%) and positioning (18%) errors. The average repeat rate in all three hospitals was 7.20%. It was found that human error has important role to repetition of radiographs. It is demonstrated that those patients having repeated radiographs received an average of 3.23 Gy·cm2. Based on the findings of this study it must be remembered that the highest repetition rate was for pelvis. Considering the radiosensitive organs related to pelvis especially in pediatric patients some special considerations must be applied for pelvis examinations. 展开更多
关键词 Patient Dose RADIOGRAPHY Exposure REPEAT Rate
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Dosimetric Characteristics of 6 MV Medical Linac at BAEC
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作者 Sudeb Kumar Roy Pretam Kumar Das +4 位作者 Rajada Khatun Md. Ashikur Rahman Shirin Akter Tushar Kumar Mohammad Monjur Ahasan 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2021年第1期38-46,共9页
Dosimetric characteristic is one of the essential parameters of a medical linear accelerator (LINAC), which must be obtained before clinical use. The dosimetric characteristics for 6 MV photon beam were measured and c... Dosimetric characteristic is one of the essential parameters of a medical linear accelerator (LINAC), which must be obtained before clinical use. The dosimetric characteristics for 6 MV photon beam were measured and compared with the corresponding published data. The study was done using a Varian linear accelerator (Model Clinac-iX) at the Institute of Nuclear Medical Physics (INMP), AERE, Savar, Dhaka, under the Bangladesh Atomic Energy Commission (BAEC). The data is taken for 10 field sizes (2 × 2, 3 × 3, 5 × 5, 7 × 7, 10 × 10, 15 × 15, 20 × 20, 25 × 25, 30 × 30 and 40 × 40 cm<sup>2</sup>) at same conditions. The measured Percent Depth Dose (PDD) curves were obtained for 6 MV photon beams with the field as mentioned above and compared with the calculated PDD curves. The measured depth dose (D<sub>max</sub>) for reference field size (FS) 10 × 10 cm<sup>2</sup> is 15.99 mm, and the PDD at 10 cm depth (D<sub>10</sub>) is 66.87% for 6 MV photon energies that are found to be compatible with the published report BJR supplement 25. The measured PDD curves for photon energies show a good agreement with the standard PDD curves. The photon beam dosimetry data found in the current study are compatible and all the tolerances are within the clinically acceptable tolerance limit. 展开更多
关键词 Linac Machines 3D Water Phantom Ionization Chamber ELECTROMETER
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The Ring Vortex: Concepts for a Novel Complex Flow Phantom for Medical Imaging
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作者 Simone Ferrari Simone Ambrogio +4 位作者 Adrian Walker Prashant Verma Andrew J. Narracott Iain Wilkinson John W. Fenner 《Open Journal of Medical Imaging》 2017年第1期28-41,共14页
Calibration of medical imaging systems that provide quantitative measures relating to complex physiological flows is challenging. Physical test objects available for the purpose either offer a known simple flow far re... Calibration of medical imaging systems that provide quantitative measures relating to complex physiological flows is challenging. Physical test objects available for the purpose either offer a known simple flow far removed from the complexity of pathology (e.g. parabolic flow in a straight pipe) or complex relevant flows in which the details of the flow behaviour are unknown. This paper presents the ring vortex as a candidate for a complex flow phantom, since it is marked by inherently complex flow features that are controllable, predictable, reproducible and stable. These characteristics are demonstrated by a combination of analytical, numerical (CFD) and experimental methods. Together they provide a consistent perspective on ring vortex behaviour and highlight qualities relevant to phantom design. Discussion of the results indicates that a liquid phantom based on the ring vortex may have merit as a complex flow phantom for multimodal imaging. Furthermore, availability of such a flow reference may also serve as a benchmark for quality assurance of simulation methodologies. 展开更多
关键词 IMAGING PHANTOM FLOW VORTEX
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