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High-resolution magnetic resonance imaging in the diagnosis and management of vertebral artery dissection:A case report
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作者 Hai-Bin Zhang Yong-Hong Duan +1 位作者 Min Zhou Ri-Chu Liang 《World Journal of Radiology》 2024年第10期593-599,共7页
BACKGROUND Vertebral artery dissection(VAD)is a rare but life-threatening condition characterized by tearing of the intimal layer of the vertebral artery,leading to stenosis,occlusion or rupture.The clinical presentat... BACKGROUND Vertebral artery dissection(VAD)is a rare but life-threatening condition characterized by tearing of the intimal layer of the vertebral artery,leading to stenosis,occlusion or rupture.The clinical presentation of VAD can be heterogeneous,with common symptoms including headache,dizziness and balance problems.Timely diagnosis and treatment are crucial for favorable outcomes;however,VAD is often missed due to its variable clinical presentation and lack of robust diagnostic guidelines.High-resolution magnetic resonance imaging(HRMRI)has emerged as a reliable diagnostic tool for VAD,providing detailed visualization of vessel wall abnormalities.CASE SUMMARY A young male patient presented with an acute onset of severe headache,vomiting,and seizures,followed by altered consciousness.Imaging studies revealed bilateral VAD,basilar artery thrombosis,multiple brainstem and cerebellar infarcts,and subarachnoid hemorrhage.Digital subtraction angiography(DSA)revealed vertebral artery stenosis but failed to detect the dissection,potentially because intramural thrombosis obscured the VAD.In contrast,HRMRI confirmed the diagnosis by revealing specific signs of dissection.The patient was managed conservatively with antiplatelet therapy and other supportive measures,such as blood pressure control and pain management.After 5 mo of rehabilitation,the patient showed significant improvement in swallowing and limb strength.CONCLUSION HR-MRI can provide precise evidence for the identification of VAD. 展开更多
关键词 Vertebral artery dissection Subarachnoid hemorrhage Brainstem infarction DIAGNOSIS high-resolution magnetic resonance imaging Case report
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Structural control of magnetic nanoparticles for positive nuclear magnetic resonance imaging
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作者 Zulaikha Ali Yunfei Zhang +5 位作者 Michael GKaul Billy Truong Deepika Bhanot Gerhard Adam Yuan-Yuan Li He Wei 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期17-28,共12页
In addition to the tens of millions of medical doses consumed annually around the world,a vast number of nuclear magnetic resonance imaging(MRI)contrast agents are being deployed in MRI research and development,offeri... In addition to the tens of millions of medical doses consumed annually around the world,a vast number of nuclear magnetic resonance imaging(MRI)contrast agents are being deployed in MRI research and development,offering precise diagnostic information,targeting capabilities,and analyte sensing.Superparamagnetic iron oxide nanoparticles(SPIONs)are notable among these agents,providing effective and versatile MRI applications while also being heavy-metal-free,bioconjugatable,and theranostic.We designed and implemented a novel two-pronged computational and experimental strategy to meet the demand for the efficient and rigorous development of SPION-based MRI agents.Our MATLAB-based modeling simulation and magnetic characterization revealed that extremely small maghemite SPIONs in the 1-3 nm range possess significantly reduced transversal relaxation rates(R_(2))and are therefore preferred for positive(T_(1)-weighted)MRI.Moreover,X-ray diffraction and X-ray absorption fine structure analyses demonstrated that the diffraction pattern and radial distribution function of our SPIONs matched those of the targeted maghemite crystals.In addition,simulations of the X-ray near-edge structure spectra indicated that our synthesized SPIONs,even at 1 nm,maintained a spherical structure.Furthermore,in vitro and in vivo MRI investigations showed that our 1-nm SPIONs effectively highlighted whole-body blood vessels and major organs in mice and could be cleared through the kidney route to minimize potential post-imaging side effects.Overall,our innovative approach enabled a swift discovery of the desired SPION structure,followed by targeted synthesis,synchrotron radiation spectroscopic studies,and MRI evaluations.The efficient and rigorous development of our high-performance SPIONs can set the stage for a computational and experimental platform for the development of future MRI agents. 展开更多
关键词 magnetic nanoparticles Structure control nuclear magnetic resonance imaging Modeling simulation X-ray absorption fine structure
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Investigating the relationship between intracranial atherosclerotic plaque remodelling and diabetes using high-resolution vessel wall imaging
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作者 Yong-Qian Mo Hai-Yu Luo +5 位作者 Han-Wen Zhang Yu-Feng Liu Kan Deng Xiao-Lei Liu Biao Huang Fan Lin 《World Journal of Diabetes》 SCIE 2024年第1期72-80,共9页
BACKGROUND Intracranial atherosclerosis,a leading cause of stroke,involves arterial plaque formation.This study explores the link between plaque remodelling patterns and diabetes using high-resolution vessel wall imag... BACKGROUND Intracranial atherosclerosis,a leading cause of stroke,involves arterial plaque formation.This study explores the link between plaque remodelling patterns and diabetes using high-resolution vessel wall imaging(HR-VWI).AIM To investigate the factors of intracranial atherosclerotic remodelling patterns and the relationship between intracranial atherosclerotic remodelling and diabetes mellitus using HR-VWI.METHODS Ninety-four patients diagnosed with middle cerebral artery or basilar artery INTRODUCTION Intracranial atherosclerotic disease is one of the main causes of ischaemic stroke in the world,accounting for approx-imately 10%of transient ischaemic attacks and 30%-50%of ischaemic strokes[1].It is the most common factor among Asian people[2].The adaptive changes in the structure and function of blood vessels that can adapt to changes in the internal and external environment are called vascular remodelling,which is a common and important pathological mechanism in atherosclerotic diseases,and the remodelling mode of atherosclerotic plaques is closely related to the occurrence of stroke.Positive remodelling(PR)is an outwards compensatory remodelling where the arterial wall grows outwards in an attempt to maintain a constant lumen diameter.For a long time,it was believed that the degree of stenosis can accurately reflect the risk of ischaemic stroke[3-5].Previous studies have revealed that lesions without significant luminal stenosis can also lead to acute events[6,7],as summarized in a recent meta-analysis study in which approximately 50%of acute/subacute ischaemic events were due to this type of lesion[6].Research[8,9]has pointed out that the PR of plaques is more dangerous and more likely to cause acute ischaemic stroke.Previous studies[10-13]have found that there are specific vascular remodelling phenomena in the coronary and carotid arteries of diabetic patients.However,due to the deep location and small lumen of intracranial arteries and limitations of imaging techniques,the relationship between intracranial arterial remodelling and diabetes is still unclear.In recent years,with the development of magnetic resonance technology and the emergence of high-resolution(HR)vascular wall imaging,a clear and multidimensional display of the intracranial vascular wall has been achieved.Therefore,in this study,HR wall imaging(HR-VWI)was used to display the remodelling characteristics of bilateral middle cerebral arteries and basilar arteries and to explore the factors of intracranial vascular remodelling and its relationship with diabetes. 展开更多
关键词 high-resolution vessel wall imaging Intracranial atherosclerosis Vascular remodelling magnetic resonance imaging
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Nuclear magnetic resonance study of the formation and dissociation process of nature gas hydrate in sandstone
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作者 Dong-hui Xing Xu-wen Qin +5 位作者 Hai-jun Qiu Hong-feng Lu Yi-ren Fan Xin-min Ge Cheng Lu Jin-wen Du 《China Geology》 CAS 2022年第4期630-636,共7页
In this work,the authors monitored the formation and dissociation process of methane hydrate in four different rock core samples through nuclear magnetic resonance(NMR)relaxation time(T_(2))and 2D imaging measurement.... In this work,the authors monitored the formation and dissociation process of methane hydrate in four different rock core samples through nuclear magnetic resonance(NMR)relaxation time(T_(2))and 2D imaging measurement.The result shows that the intensity of T_(2) spectra and magnetic resonance imaging(MRI)signals gradually decreases in the hydrate formation process,and at the same time,the T_(2) spectra move toward the left domain as the growth of hydrate in the pores of the sample accelerates the decay rate.The hydrate grows and dissociates preferentially in the purer sandstone samples with larger pore size and higher porosity.Significantly,for the sample with lower porosity and higher argillaceous content,the intensity of the T_(2) spectra also shows a trend of a great decrease in the hydrate formation process,which means that high-saturation gas hydrate can also be formed in the sample with higher argillaceous content.The changes in MRI of the sample in the process show that the formation and dissociation of methane hydrate can reshape the distribution of water in the pores. 展开更多
关键词 Nature gas hydrates(NGHs) Methane hydrate nuclear magnetic resonance(NMR) magnetic resonance imaging(MRI) Formation and dissociation Saturation Berea sandstone Marine hydrates production test Oil and gas exploration engineering
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High-resolution Magnetic Resonance Imaging of Moyamoya Disease 被引量:8
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作者 Le-Bao Yu Qian Zhang +2 位作者 Zhi-Yong Shi Ming-Qiu Wang Dong Zhang 《Chinese Medical Journal》 SCIE CAS CSCD 2015年第23期3231-3237,共7页
Objective: To introduce the imaging characteristics of moyamoya disease (MMD) using high-resolution magnetic resonance imaging (HR-MRI) and to discuss the role of HR-MRI in differentiating MMD from other intracra... Objective: To introduce the imaging characteristics of moyamoya disease (MMD) using high-resolution magnetic resonance imaging (HR-MRI) and to discuss the role of HR-MRI in differentiating MMD from other intracranial artery diseases, especially intracranial atherosclerotic disease (ICAD). Data Sources: This review was based on the data in articles published between 2005 and 2015, which were obtained from PubMed. The keywords included HR-MRI, MMD, ICAD, and intracranial artery diseases. Study Selection: Articles related to HR-MRI for MMD or other intracranial artery diseases were selected for review. Results: There are differences between the characteristic patterns of HR-MRI in MMD and ICAD. MMD is associated with inward remodeling, smaller outer diameters, concentric occlusive lesions and homogeneous signal intensity, while ICAD is more likely to be associated with outward remodeling, normal outer diameters, eccentric occlusive lesions, and heterogeneous signal intensity. Other intracranial artery diseases, such as dissection and vasculitis, also have distinctive characteristics in HR-MRI. HR-MRI may become a useful tool for the differential diagnosis of MMD in the future. Conclusions: HR-MRI of MMD provides a more in-depth understanding of MMD, and it is helpful in evaluating pathological changes in the vessel wall and in differentiating MMD from other intracranial artery steno-occlusive diseases, particularly ICAD.以 展开更多
关键词 ATHEROSCLEROSIS high-resolution magnetic resonance imaging Intracranial Artery Steno-occlusive Disease lntracrania Atherosclerotic Disease Moyamoya Disease
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Multi-modality parathyroid imaging:A shifting paradigm
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作者 Shrea Gulati Sunil Chumber +3 位作者 Gopal Puri Stanzin Spalkit N A Damle CJ Das 《World Journal of Radiology》 2023年第3期69-82,共14页
The goal of parathyroid imaging in hyperparathyroidism is not diagnosis,rather it is the localization of the cause of hyperparathyroidism for planning the best therapeutic approach.Hence,the role of imaging to accurat... The goal of parathyroid imaging in hyperparathyroidism is not diagnosis,rather it is the localization of the cause of hyperparathyroidism for planning the best therapeutic approach.Hence,the role of imaging to accurately and precisely localize the abnormal parathyroid tissue is more important than ever to facilitate minimally invasive parathyroidectomy over bilateral neck exploration.The common causes include solitary parathyroid adenoma,multiple parathyroid adenomas,parathyroid hyperplasia and parathyroid carcinoma.It is highly imperative for the radiologist to be cautious of the mimics of parathyroid lesions like thyroid nodules and lymph nodes and be able to differentiate them on imaging.The various imaging modalities available include high resolution ultrasound of the neck,nuclear imaging studies,four-dimensional computed tomography(4D CT)and magnetic resonance imaging.Contrast enhanced ultrasound is a novel technique which has been recently added to the armam-entarium to differentiate between parathyroid adenomas and its mimics.Through this review article we wish to review the imaging features of parathyroid lesions on various imaging modalities and present an algorithm to guide their radiological differentiation from mimics. 展开更多
关键词 Parathyroid adenoma ULTRASOUND Four-dimensional computed tomography magnetic resonance imaging nuclear imaging Contrast enhanced ultrasound
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Multimodality imaging and treatment of paranasal sinuses nuclear protein in testis carcinoma:A case report 被引量:2
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作者 Wen-Peng Huang Ge Gao +5 位作者 Yong-Kang Qiu Qi Yang Le-Le Song Zhao Chen Jian-Bo Gao Lei Kang 《World Journal of Clinical Cases》 SCIE 2022年第33期12395-12403,共9页
BACKGROUND Nuclear protein in testis(NUT) carcinoma is a rare aggressive malignant epithelial cell tumor, previously known as NUT midline carcinoma(NMC), characterized by an acquired rearrangement of the gene encoding... BACKGROUND Nuclear protein in testis(NUT) carcinoma is a rare aggressive malignant epithelial cell tumor, previously known as NUT midline carcinoma(NMC), characterized by an acquired rearrangement of the gene encoding NUT on chromosome 15q14. Due to the lack of characteristic pathological features, it is often underdiagnosed and misdiagnosed. A variety of methods can be used to diagnose NMC, including immunohistochemistry, karyotyping, fluorescence in situ hybridization, reverse transcription-polymerase chain reaction, and next-generation sequencing. So far, there is no standard treatment plan for NMC and the prognosis is poor, related to its rapid progression, easy recurrence, and unsatisfactory treatment outcome.CASE SUMMARY A 58-year-old female came to our hospital with a complaint of eye swelling and pain for 8 d. The diagnosis of NMC was confirmed after postoperative pathology and genetic testing. The patient developed nausea and vomiting, headache, and loss of vision in both eyes to blindness after surgery. Magnetic resonance imaging(MRI) and positron emission tomography/computed tomography(PET/CT) performed after 1.5 mo postoperatively suggested tumor recurrence. The patient obtained remission after radiation therapy to some extent and after initial treatment with anti-angiogenic drugs and sonodynamic therapy(SDT), but cannot achieve long-term stability and eventually developed distant metastases, with an overall survival of only 17 mo.CONCLUSION For patients with rapidly progressing sinus tumors and poor response to initial treatment, the possibility of NMC should be considered and immunohistochemical staining with anti-NUT should be performed as soon as possible, combined with genetic testing if necessary. CT, MRI, and PET/CT imaging are essential for the staging, management, treatment response assessment and monitoring of NMC. This case is the first attempt to apply heat therapy and SDT in the treatment of NMC, unfortunately, the prognosis remained poor. 展开更多
关键词 nuclear protein in testis RECURRENCE magnetic resonance imaging Treatment X-ray computed tomography Positron emission tomography Case report
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Non-invasive assessment of intracranial wall shear stress using high-resolution magnetic resonance imaging in combination with computational fluid dynamics technique
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作者 Yuwen Chen Jia Liu +10 位作者 Mingli Li Yannan Yu Zhengzheng Yan Wenshin Shiu Bokai Wu Zaiheng Cheng Yao Meng Yang Liu Weizhuang Yuan Zongmuyu Zhang Weihai Xu 《Fundamental Research》 CAS 2022年第2期329-334,共6页
In vivo studies on association between wall shear stress(WSS)and intracranial plaque are deficient.Based on the three-dimensional T1-weighted high-resolution magnetic resonance imaging(3DT1 HR-MRI)data of patients wit... In vivo studies on association between wall shear stress(WSS)and intracranial plaque are deficient.Based on the three-dimensional T1-weighted high-resolution magnetic resonance imaging(3DT1 HR-MRI)data of patients with low-grade stenotic(<50%)atherosclerotic middle cerebral artery(MCA)and subjects with normal MCA,we built a three-dimensional reconstructed WSS model by computational fluid dynamics(CFD)technique.Three-dimensional registration of the CFD model to the HR-MRI was performed with projections based on the resolution and thickness of the images.The relationships between the Wss at each side of the vessel wall and plaque location were analyzed.A total of 94 MCA plaques from 43 patients and 50 normal MCAs were analyzed.In the normal MCAs,WSS was lower at the ventral-inferior wall than at the dorsal-superior wall(proximal segment,p<0.001;middle segment,p<0.001)and lower at the inner wall than at the outer wall of the MCA curve(p<0.001).In atherosclerotic MCAs,similar low Wss regions were observed where plaques developed.The WSS ratio of the ventral-inferior wall to the dorsal-superior wall in atherosclerotic MCAs was lower than that in normal MCAs(p=0.002).The WSS_(inmer-outer)ratio in atherosclerotic MCAs was lower than that in normal MCAs(p=0.002).Low WSS was associated with MCA atherosclerosis formation and occurred mainly at the ventral inferior wall,which was anatomically opposite the orifices of penetrating arteries,and at the inner wall of the MCA curve.Overall,the results were well consistent with the low WSS theory in atherosclerosis formation.The reconstructed WSS model is a promising novel method for assessing an individualized vascular profile once validated by further studies. 展开更多
关键词 Intracranial atherosclerosis Wall shear stress Atherosclerotic plaque high-resolution magnetic resonance imaging Computational fluid dynamics
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Advances in high-resolution nuclear magnetic resonance methods in inhomogeneous magnetic fields using intermolecular multiple quantum coherences 被引量:3
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作者 CHEN Zhong LIN MeiJin +1 位作者 CHEN Xi CAI ShuHui 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2009年第1期58-69,共12页
Strong and extremely homogeneous static magnetic field is usually required for high-resolution nu-clear magnetic resonance (NMR). However, in the cases of in vivo and so on, the magnetic field inho-mogeneity owing to ... Strong and extremely homogeneous static magnetic field is usually required for high-resolution nu-clear magnetic resonance (NMR). However, in the cases of in vivo and so on, the magnetic field inho-mogeneity owing to magnetic susceptibility variation in samples is unavoidable and hard to eliminate by conventional methods such as shimming. Recently, intermolecular multiple quantum coherences (iMQCs) have been employed to eliminate inhomogeneous broadening and obtain high-resolution NMR spectra, especially for in vivo samples. Compared to other high-resolution NMR methods, iMQC method exhibits its unique feature and advantage. It simultaneously holds information of chemical shifts, multiplet structures, coupling constants, and relative peak areas. All the information is often used to analyze and characterize molecular structures in conventional one-dimensional NMR spec-troscopy. In this work, recent technical developments including our results in this field are summarized; the high-resolution mechanism is analyzed and comparison with other methods based on interactions between spins is made; comments on the current situation and outlook on the research directions are also made. 展开更多
关键词 nuclear magnetic resonance high-resolution INHOMOGENEOUS magnetic FIELDS INTERMOLECULAR multiple quantum COHERENCE
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Grade classification of neuroepithelial tumors using high-resolution magic-angle spinning proton nuclear magnetic resonance spectroscopy and pattern recognition 被引量:5
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作者 CHEN WenXue LOU HaiYan +9 位作者 ZHANG HongPing NIE Xiu LAN WenXian YANG YongXia XIANG Yun QI JianPin LEI Hao TANG HuiRu CHEN FenEr DENG Feng 《Science China(Life Sciences)》 SCIE CAS 2011年第7期606-616,共11页
Clinical data have shown that survival rates vary considerably among brain tumor patients,according to the type and grade of the tumor.Metabolite profiles of intact tumor tissues measured with high-resolution magic-an... Clinical data have shown that survival rates vary considerably among brain tumor patients,according to the type and grade of the tumor.Metabolite profiles of intact tumor tissues measured with high-resolution magic-angle spinning proton nuclear magnetic resonance spectroscopy (HRMAS 1H NMRS) can provide important information on tumor biology and metabolism.These metabolic fingerprints can then be used for tumor classification and grading,with great potential value for tumor diagnosis.We studied the metabolic characteristics of 30 neuroepithelial tumor biopsies,including two astrocytomas (grade I),12 astrocytomas (grade II),eight anaplastic astrocytomas (grade III),three glioblastomas (grade IV) and five medulloblastomas (grade IV) from 30 patients using HRMAS 1H NMRS.The results were correlated with pathological features using multivariate data analysis,including principal component analysis (PCA).There were significant differences in the levels of N-acetyl-aspartate (NAA),creatine,myo-inositol,glycine and lactate between tumors of different grades (P<0.05).There were also significant differences in the ratios of NAA/creatine,lactate/creatine,myo-inositol/creatine,glycine/creatine,scyllo-inositol/creatine and alanine/creatine (P<0.05).A soft independent modeling of class analogy model produced a predictive accuracy of 87% for high-grade (grade III-IV) brain tumors with a sensitivity of 87% and a specificity of 93%.HRMAS 1H NMR spectroscopy in conjunction with pattern recognition thus provides a potentially useful tool for the rapid and accurate classification of human brain tumor grades. 展开更多
关键词 neuroepithelial tumor grade classification high-resolution magic-angle spinning nuclear magnetic resonance (HRMASNMR) spectroscopy METABONOMICS pattern recognition
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igh-resolution Magnetic Resonance Vessel Wall Imaging for Intracranial Arterial Stenosis 被引量:31
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作者 Xian-Jin Zhu Wu Wang Zun-Jing Liu 《Chinese Medical Journal》 SCIE CAS CSCD 2016年第11期1363-1370,共8页
Objective: To discuss the feasibility and clinical value of high-resolution magnetic resonance vessel wall imaging (HRMR VWI) for intracranial arterial stenosis. Date Sources: We retrieved information from PubMed ... Objective: To discuss the feasibility and clinical value of high-resolution magnetic resonance vessel wall imaging (HRMR VWI) for intracranial arterial stenosis. Date Sources: We retrieved information from PubMed database up to December 2015, using various search terms including vessel wall imaging (VWI), high-resolution magnetic resonance imaging, intracranial arterial stenosis, black blood, and intracranial atherosclerosis. Study Selection: We reviewed peer-reviewed articles printed in English on imaging technique of VWI and characteristic findings of various intracranial vasculopathies on VWI. We organized this data to explain the value of VWI in clinical application. Results: VWI with black blood technique could provide high-quality images with submillimeter voxel size, and display both the vessel wall and lumen of intracranial artery simultaneously. Various intracranial vasculopathies (atherosclerotic or nonatherosclerotic) had differentiating features including pattern of wall thickening, enhancement, and vessel remodeling on VWI. This technique could be used for determining causes of stenosis, identification of stroke mechanism, risk-stratifying patients, and directing therapeutic management in clinical practice. In addition, a new morphological classification based on VWI could be established for predicting the efficacy of endovascular therapy. Conclusions: This review highlights the value of HRMR VWI for discrimination of different intracranial vasculopathies and directing therapeutic management. 展开更多
关键词 Black Blood high-resolution magnetic resonance images Vessel Wall imaging
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Role of functional imaging in the development and refinement of invasive neuromodulation for psychiatric disorders 被引量:6
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作者 Nolan R Williams Joseph J Taylor +3 位作者 Kayla Lamb Colleen A Hanlon E Baron Short Mark S George 《World Journal of Radiology》 CAS 2014年第10期756-778,共23页
Deep brain stimulation(DBS) is emerging as a pow-erful tool for the alleviation of targeted symptoms in treatment-resistant neuropsychiatric disorders. Despite the expanding use of neuropsychiatric DBS, the mecha-nism... Deep brain stimulation(DBS) is emerging as a pow-erful tool for the alleviation of targeted symptoms in treatment-resistant neuropsychiatric disorders. Despite the expanding use of neuropsychiatric DBS, the mecha-nisms responsible for its effects are only starting to be elucidated. Several modalities such as quantitative elec-troencephalography as well a intraoperative recordings have been utilized to attempt to understand the under-pinnings of this new treatment modality, but functional imaging appears to offer several unique advantages. Functional imaging techniques like positron emission tomography, single photon emission computed tomog-raphy and functional magnetic resonance imaging have been used to examine the effects of focal DBS on activ-ity in a distributed neural network. These investigations are critical for advancing the field of invasive neuro-modulation in a safe and effective manner, particularly in terms of defining the neuroanatomical targets and refining the stimulation protocols. The purpose of this review is to summarize the current functional neuroim-aging findings from neuropsychiatric DBS implantation for three disorders: treatment-resistant depression, obsessive-compulsive disorder, and Tourette syndrome. All of the major targets will be discussed(Nucleus ac-cumbens, anterior limb of internal capsule, subcallosal cingulate, Subthalamic nucleus, Centromedial nucleus of the thalamus-Parafasicular complex, frontal pole, and dorsolateral prefrontal cortex). We will also address some apparent inconsistencies within this literature, and suggest potential future directions for this promis-ing area. 展开更多
关键词 Deep brain stimulation Functional neuroimaging Functional magnetic resonance imaging Functional magnetic resonance imaging Cortical stimulation nuclear imaging
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Two-state kinetics characterized by image analysis of nuclear magnetic resonance spectra 被引量:1
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作者 YAN Yongbin LUO Xuechun +1 位作者 ZHOU Haimeng ZHANG Riqing 《Chinese Science Bulletin》 SCIE EI CAS 2002年第5期389-393,共5页
Nuclear magnetic resonance (NMR) spectros-copy has become an important tool in modern biological research. NMR spectra image analysis can be used to analyze the kinetics of biomacromolecular conformational changes. Th... Nuclear magnetic resonance (NMR) spectros-copy has become an important tool in modern biological research. NMR spectra image analysis can be used to analyze the kinetics of biomacromolecular conformational changes. The relationship between the image parameters and the protein dynamics was investigated by using a small globular protein ω-conotoxin SO3 (ω-CTX SO3). The physical meanings of the image parameters were characterized from the results. Comparison of the data from the traditional integral area of specific resonance peaks method and the NMR image analysis method showed the advantages of using NMR spectra image analysis for kinetic analysis of two-state processes monitored by 1D proton NMR. 展开更多
关键词 image analysis PROTON nuclear magnetic resonance re-ductive UNFOLDING UNFOLDING dynamics.
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Multi-modality imaging of cardiac amyloidosis: Contemporary update 被引量:2
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作者 Tom Kai Ming Wang Ossama K Abou Hassan +1 位作者 Wael Jaber Bo Xu 《World Journal of Radiology》 CAS 2020年第6期87-100,共14页
Cardiac amyloidosis is a heterogeneous and challenging diagnostic disease with poor prognosis that is now being altered by introduction of new therapies.Echocardiography remains the first-line imaging tool, and when d... Cardiac amyloidosis is a heterogeneous and challenging diagnostic disease with poor prognosis that is now being altered by introduction of new therapies.Echocardiography remains the first-line imaging tool, and when disease is suspected on echocardiography, cardiac magnetic resonance imaging and nuclear imaging play critical roles in the non-invasive diagnosis and evaluation of cardiac amyloidosis. Advances in multi-modality cardiac imaging allowing earlier diagnosis and initiation of novel therapies have significantly improved the outcomes in these patients. Cardiac imaging also plays important roles in the risk stratification of patients presenting with cardiac amyloidosis. In the current review, we provide a clinical and imaging focused update, and importantly outline the imaging protocols, diagnostic and prognostic utility of multimodality cardiac imaging in the assessment of cardiac amyloidosis. 展开更多
关键词 Cardiac amyloidosis ECHOCARDIOGRAPHY Cardiac magnetic resonance imaging nuclear imaging
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Diagnostic and prognostic value of cardiac imaging in amyloidosis 被引量:1
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作者 Rafael Vidal-Perez Raquel Vázquez-García +5 位作者 Gonzalo Barge-Caballero Alberto Bouzas-Mosquera Rafaela Soler-Fernandez Jose Maria Larrañaga-Moreira Maria Generosa Crespo-Leiro Jose Manuel Vazquez-Rodriguez 《World Journal of Cardiology》 2020年第12期599-614,共16页
Amyloidosis is an infiltrative disease caused by extracellular protein deposition that has accumulated a lot of scientific production in recent years.Different types of amyloidosis can affect the heart.Transthyretin a... Amyloidosis is an infiltrative disease caused by extracellular protein deposition that has accumulated a lot of scientific production in recent years.Different types of amyloidosis can affect the heart.Transthyretin amyloidosis and light chain amyloidosis are the two most common types of cardiac amyloidosis.These entities have a poor prognosis,so accurate diagnostic techniques are imperative for determining an early therapeutic approach.Recent advances in cardiac imaging and diagnostic strategies show that these tools are safe and can avoid the use of invasive diagnostic techniques to histological confirmation,such as endomyocardial biopsy.We performed a review on the diagnostic and prognostic implications of different cardiac imaging techniques in cardiac amyloidosis.We mainly focus on reviewing echocardiography,cardiac magnetic resonance,computed tomography and nuclear imaging techniques and the different safety measurements that can be done with each of them. 展开更多
关键词 Cardiac imaging techniques Transthyretin cardiac amyloidosis Immunoglobulin light-chain amyloidosis ECHOCARDIOGRAPHY magnetic resonance imaging nuclear imaging
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Multi-modality imaging in transthyretin amyloid cardiomyopathy
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作者 Bryan Paul Traynor Aamir Shamsi Victor Voon 《World Journal of Cardiology》 CAS 2019年第11期266-276,共11页
Transthyretin amyloid(TTR)cardiomyopathy is a disease of insidious onset,which is often accompanied by debilitating neurological and/or cardiac complications.The true prevalence is not fully known due to its elusive p... Transthyretin amyloid(TTR)cardiomyopathy is a disease of insidious onset,which is often accompanied by debilitating neurological and/or cardiac complications.The true prevalence is not fully known due to its elusive presentation,being often under-recognized and usually diagnosed only late in its natural history and in older patients.Because of this,effective treatment options are usually precluded by multiple comorbidities and frailty associated with such patients.Therefore,high clinical suspicion with earlier and better detection of this disease is needed.In this review,the novel applications of multimodality imaging in the diagnostic pathway of TTR cardiomyopathy are explored.These include the complimentary roles of transthoracic echocardiography,cardiac magnetic resonance,nuclear scintigraphy and positron emission tomography in quantifying cardiac dysfunction,diagnosis and risk stratification.Recent advances in novel therapeutic options for TTR have further enhanced the importance of a timely and accurate diagnosis of this disease. 展开更多
关键词 MULTIMODALITY imaging CARDIAC AMYLOIDOSIS TRANSTHYRETIN Echocardiography CARDIAC magnetic resonance nuclear imaging
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“How many times must a man look up before he can really see the sky?” Rheumatic cardiovascular disease in the era of multimodality imaging
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作者 Sophie I Mavrogeni George Markousis-Mavrogenis +3 位作者 David Hautemann Kees van Wijk Hans J Reiber Genovefa Kolovou 《World Journal of Methodology》 2015年第3期136-143,共8页
Cardiovascular involvement in rheumatic diseases(RD) is the result of various pathophysiologic mechanisms including inflammation, accelerated atherosclerosis, myocardial ischemia, due to micro- or macro-vascular lesio... Cardiovascular involvement in rheumatic diseases(RD) is the result of various pathophysiologic mechanisms including inflammation, accelerated atherosclerosis, myocardial ischemia, due to micro- or macro-vascular lesions and fibrosis. Noninvasive cardiovascular imaging, including echocardiography, nuclear techniques, cardiovascular computed tomography and cardiovascular magnetic resonance, represents the main diagnostic tool for early, non-invasive diagnosis of heart disease in RD. However, in the era of multimodality imaging and financial crisis there is an imperative need for rational use of imaging techniques in order to obtain the maximum benefit at the lowest possible cost for the health insurance system. The oligo-asymptomatic cardiovascular presentation and the high cardiovascular mortality of RD necessitate a reliable and reproducible diagnostic approach to catch early cardiovascular involvement. Echocardiography remains the routine cornerstone of cardiovascular evaluation. However, a normal echocardiogram can not always exclude cardiac involvement and/or identify heart disease acuity and pathophysiology. Therefore, cardiovascular magnetic resonance is a necessary adjunct complementary to echocardiography, especially in new onset heart failure and when there are conflicting data from clinical, electrocardiographic and echocardiographic evaluation of RD patients. 展开更多
关键词 Echocardiography CARDIOVASCULAR magnetic resonance nuclear imaging CARDIOVASCULAR computed tomography Myocardial perfusion-fibrosis Coronary artery DISEASE VASCULITIS RHEUMATIC CARDIOVASCULAR DISEASE MYOCARDITIS
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Imaging related to underlying immunological and pathological processes in COVID-19
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作者 Elena Ilieva Alexandra Boyapati +4 位作者 Lyubomir Chervenkov Milena Gulinac Jordan Borisov Kamelia Genova Tsvetelina Velikova 《World Journal of Clinical Infectious Diseases》 2022年第1期1-19,共19页
The introduction of coronavirus disease-2019(COVID-19)as a global pandemic has contributed to overall morbidity and mortality.With a focus on understanding the immunology and pathophysiology of the disease,these featu... The introduction of coronavirus disease-2019(COVID-19)as a global pandemic has contributed to overall morbidity and mortality.With a focus on understanding the immunology and pathophysiology of the disease,these features can be linked with the respective findings of imaging studies.Thus,the constellation between clinical presentation,histological,laboratory,immunological,and imaging results is crucial for the proper management of patients.The purpose of this article is to examine the role of imaging during the particular stages of severe acute respiratory syndrome coronavirus 2 infection–asymptomatic stage,typical and atypical COVID-19 pneumonia,acute respiratory distress syndrome,multiorgan failure,and thrombosis.The use of imaging methods to assess the severity and duration of changes is crucial in patients with COVID-19.Radiography and computed tomography are among the methods that allow accurate characterization of changes. 展开更多
关键词 Coronavirus disease-2019 Ultrasound Computed tomography magnetic resonance imaging Ground-glass opacity Acute respiratory distress syndrome Cytokine storm COVID-19 reporting and data system high-resolution computed tomography Severe acute respiratory syndrome coronavirus 2
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基于不同维度低场核磁共振技术的大豆含油率检测与判别
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作者 张宇 赵亚楠 +1 位作者 赵健翔 宋平 《农业工程学报》 EI CAS CSCD 北大核心 2024年第4期337-344,共8页
大豆含油率的高低直接影响榨油与育种结果。为探究大豆含油率的最佳检测方法与构建含油率高低判别模型,该研究基于不同维度低场核磁共振(low field nuclear magnetic resonance,LF-NMR)技术,以国标法为对照,利用LF-NMR波谱和LF-NMR含油... 大豆含油率的高低直接影响榨油与育种结果。为探究大豆含油率的最佳检测方法与构建含油率高低判别模型,该研究基于不同维度低场核磁共振(low field nuclear magnetic resonance,LF-NMR)技术,以国标法为对照,利用LF-NMR波谱和LF-NMR含油含水率软件检测大豆含油率;核磁共振成像(magnetic resonance imaging,MRI)结合深度学习,建立大豆含油率高低判别模型。引入低场二维核磁共振(low field two-dimensional nuclear magnetic resonance,LF-2D-NMR)技术,定性分析一维波谱中信号重叠无法区分组分的问题。试验结果表明,LF-NMR含油含水率软件能快速准确检测大豆含油率,T1-T2二维核磁图谱成功解决了自由水和油信号重叠问题。利用U-net++深度学习模型对MRI成像的矢状面、冠状面、横截面以及三面混合数据集进行训练,其中横截面评价指标与其他数据集相比更优,语义分割部分中平均交并比(mean intersection over union,mIoU)约0.9058,全局准确率0.9980,训练后的模型能够将MRI图像识别并分割,快速判别大豆含油率高低。试验证明,LF-NMR及MRI能够快速无损掌握大豆含油率信息,为大豆的高油育种提供了新思路和技术支持。 展开更多
关键词 低场核磁共振 低场二维核磁共振 磁共振成像 大豆含油率 深度学习
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基于恒定梯度编码一维选层T_(2)谱的胶结砂岩层析成像方法
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作者 吴土荣 陈金定 +3 位作者 张群 赵希春 郭敏灵 程芳桂 《测井技术》 CAS 2024年第2期190-197,共8页
核磁共振成像是探究岩心尺度非均质性的先进技术,受岩石复杂性和编码技术影响,现有方法效果不佳。基于梯度场的二维/三维核磁共振技术成像容易但信噪比低,无梯度场的传统选层T_(2)谱(频率编码/相位编码)方法效率低。该研究提出恒定梯度... 核磁共振成像是探究岩心尺度非均质性的先进技术,受岩石复杂性和编码技术影响,现有方法效果不佳。基于梯度场的二维/三维核磁共振技术成像容易但信噪比低,无梯度场的传统选层T_(2)谱(频率编码/相位编码)方法效率低。该研究提出恒定梯度编码一维选层T_(2)谱层析成像方法,做到了成像数据体量小、信噪比高且信号更完整。层析T_(2)谱图像及其热度分布,能够有效表征毛细管压力和成岩作用对流体非均匀分布的影响。饱和油状态时,T_(2)谱层间差异性反映成岩作用影响。高饱和油阶段,轴向热度图反映了低毛细管压力游离油的脱出规律。完全驱替后毛细管压力进入稳定状态,轴向热度图反映了微孔中吸附油赋存状态的差异。该技术在胶结砂岩气驱油实验中取得了良好效果,并对解析强非均质岩石渗流规律有重要作用。 展开更多
关键词 岩心核磁共振 T_(2)谱成像 梯度编码 毛细管压力 非均质性
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