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T2* magnetic resonance imaging of the liver in thalassemic patients in Iran 被引量:8
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作者 Farhad Zamani Sara Razmjou +3 位作者 Shahram Akhlaghpoor Seyyedeh-Masoomeh Eslami Azita Azarkeivan Afsaneh Amiri 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第4期522-525,共4页
AIM: To investigate the accuracy of T2*-weighted magnetic resonance imaging (MRI T2*) in the evaluation of iron overload in beta-thalassemia major patients. METHODS: In this cross-sectional study, 210 patients with be... AIM: To investigate the accuracy of T2*-weighted magnetic resonance imaging (MRI T2*) in the evaluation of iron overload in beta-thalassemia major patients. METHODS: In this cross-sectional study, 210 patients with beta-thalassemia major having regular blood transfusions were consecutively enrolled. Serum ferritin levels were measured, and all patients underwent MRI T2* of the liver. Liver biopsy was performed in 53 patients at an interval of no longer than 3 mo after the MRIT2* in each patient. The amount of iron was assessed in both MRI T2* and liver biopsy specimens of each patient. RESULTS: Patients’ ages ranged from 8 to 54 years with a mean of 24.59 ± 8.5 years. Mean serum ferritin level was 1906 ± 1644 ng/mL. Liver biopsy showed a moderate negative correlation with liver MRI T2* (r = -0.573, P = 0.000) and a low positive correlation with ferritin level (r = 0.350, P = 0.001). Serum ferritin levels showed a moderate negative correlation with liver MRI T2* values (r = -0.586, P = 0.000). CONCLUSION: Our study suggests that MRI T2* is a non-invasive, safe and reliable method for detecting iron load in patients with iron overload. 展开更多
关键词 T2*-weighted magnetic resonance imaging LIVER Iron overload Major thalassemia FERRITIN
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Magnetic Resonance Imaging and Histopathological Analysis of Experimental Muscle Injuries in a Rabbit 被引量:7
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作者 YAN Dong ZHANG Jing +4 位作者 LIANG Wei SUN Jing LIU Bao Yue TIAN Wei CHENG Xiao Guang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第10期841-848,共8页
Objective To investigate the correlation of magnetic resonance imaging (MRI) with histopathologica changes, and to evaluate T2 mapping in assessing muscle trauma in a rabbit model of muscle injury. Methods We divide... Objective To investigate the correlation of magnetic resonance imaging (MRI) with histopathologica changes, and to evaluate T2 mapping in assessing muscle trauma in a rabbit model of muscle injury. Methods We divided 35 rabbits into seven groups that each represented a different time point after intramuscular hemorrhage and muscle injury. Hemorrhage was created by injecting autologous blood into the left legs, and muscle injury was created by scalpel incision of the biceps femoris of the right legs. At different time points, the rabbits underwent Tl-weighted imaging and T2-weighted imaging (TzWl and T2Wl) and T2 mapping. T2 relaxation times were measured, and the corresponding samples were evaluated for pathological changes. Results After 2 h, the intramuscular hemorrhage model demonstrated an increased signal intensity on both TlWl and T2Wl. Histological examination showed erythrocytes within the muscle bundle. On days 1 and 3, the MRI signals were decreased, and there were no significant changes after day 7. From 2 h to 3 days, the muscle-injury model showed a high signal on both TzWl and T2Wl. Corresponding pathological changes included rupture and edema of muscle fibers, and inflammation. The abnormal signals were reduced on day 7. After day 14, the T2Wl intensity remained high. TlWl showed no abnormal changes, but some models showed a high signal, representing fresh bleeding and fatty tissue. T2 relaxation times were significantly different between the central and marginal regions, and between the marginal and normal regions. Conclusion MRI clearly demonstrates intramuscular hemorrhage and muscle injury, which correlate well with histopathological changes. Tz mapping is useful in assessing the extent of injury. 展开更多
关键词 Muscle injury Intramuscular hemorrhage magnetic resonance imaging T2 mapping
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A multiple-tissue-specific magnetic resonance imaging model for diagnosing Parkinson’s disease: a brain radiomics study 被引量:2
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作者 Xiao-Jun Guan Tao Guo +15 位作者 Cheng Zhou Ting Gao Jing-Jing Wu Victor Han Steven Cao Hong-Jiang Wei Yu-Yao Zhang Min Xuan Quan-Quan Gu Pei-Yu Huang Chun-Lei Liu Jia-Li Pu Bao-Rong Zhang Feng Cui Xiao-Jun Xu Min-Ming Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第12期2743-2749,共7页
Brain radiomics can reflect the characteristics of brain pathophysiology.However,the value of T1-weighted images,quantitative susceptibility mapping,and R2*mapping in the diagnosis of Parkinson’s disease(PD)was under... Brain radiomics can reflect the characteristics of brain pathophysiology.However,the value of T1-weighted images,quantitative susceptibility mapping,and R2*mapping in the diagnosis of Parkinson’s disease(PD)was underestimated in previous studies.In this prospective study to establish a model for PD diagnosis based on brain imaging information,we collected high-resolution T1-weighted images,R2*mapping,and quantitative susceptibility imaging data from 171 patients with PD and 179 healthy controls recruited from August 2014 to August 2019.According to the inclusion time,123 PD patients and 121 healthy controls were assigned to train the diagnostic model,while the remaining 106 subjects were assigned to the external validation dataset.We extracted 1408 radiomics features,and then used data-driven feature selection to identify informative features that were significant for discriminating patients with PD from normal controls on the training dataset.The informative features so identified were then used to construct a diagnostic model for PD.The constructed model contained 36 informative radiomics features,mainly representing abnormal subcortical iron distribution(especially in the substantia nigra),structural disorganization(e.g.,in the inferior temporal,paracentral,precuneus,insula,and precentral gyri),and texture misalignment in the subcortical nuclei(e.g.,caudate,globus pallidus,and thalamus).The predictive accuracy of the established model was 81.1±8.0%in the training dataset.On the external validation dataset,the established model showed predictive accuracy of 78.5±2.1%.In the tests of identifying early and drug-naïve PD patients from healthy controls,the accuracies of the model constructed on the same 36 informative features were 80.3±7.1%and 79.1±6.5%,respectively,while the accuracies were 80.4±6.3%and 82.9±5.8%for diagnosing middle-to-late PD and those receiving drug management,respectively.The accuracies for predicting tremor-dominant and non-tremor-dominant PD were 79.8±6.9%and 79.1±6.5%,respectively.In conclusion,the multiple-tissue-specific brain radiomics model constructed from magnetic resonance imaging has the ability to discriminate PD and exhibits the advantages for improving PD diagnosis. 展开更多
关键词 diagnosis imaging biomarker iron magnetic resonance imaging NEUROimaging Parkinson’s disease quantitative susceptibility mapping R2*mapping radiomics T1-weighted imaging
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Quantitative multiparametric magnetic resonance imaging can aid non-alcoholic steatohepatitis diagnosis in a Japanese cohort 被引量:2
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作者 Kento Imajo Louise Tetlow +14 位作者 Andrea Dennis Elizabeth Shumbayawonda Sofia Mouchti Timothy J Kendall Eve Fryer Shogi Yamanaka Yasushi Honda Takaomi Kessoku Yuji Ogawa Masato Yoneda Satoru Saito Catherine Kelly Matt D Kelly Rajarshi Banerjee Atsushi Nakajima 《World Journal of Gastroenterology》 SCIE CAS 2021年第7期609-623,共15页
BACKGROUND Non-invasive assessment of non-alcoholic steatohepatitis(NASH)is increasing in desirability due to the invasive nature and costs associated with the current form of assessment;liver biopsy.Quantitative mult... BACKGROUND Non-invasive assessment of non-alcoholic steatohepatitis(NASH)is increasing in desirability due to the invasive nature and costs associated with the current form of assessment;liver biopsy.Quantitative multiparametric magnetic resonance imaging(mpMRI)to measure liver fat(proton density fat fraction)and fibroinflammatory disease[iron-corrected T1(cT1)],as well as elastography techniques[vibration-controlled transient elastography(VCTE)liver stiffness measure],magnetic resonance elastography(MRE)and 2D Shear-Wave elastography(SWE)to measure stiffness and fat(controlled attenuated parameter,CAP)are emerging alternatives which could be utilised as safe surrogates to liver biopsy.AIM To evaluate the agreement of non-invasive imaging modalities with liver biopsy,and their subsequent diagnostic accuracy for identifying NASH patients.METHODS From January 2019 to February 2020,Japanese patients suspected of NASH were recruited onto a prospective,observational study and were screened using noninvasive imaging techniques;mpMRI with LiverMultiScan®,VCTE,MRE and 2DSWE.Patients were subsequently biopsied,and samples were scored by three independent pathologists.The diagnostic performances of the non-invasive imaging modalities were assessed using area under receiver operating characteristic curve(AUC)with the median of the histology scores as the gold standard diagnoses.Concordance between all three independent pathologists was further explored using Krippendorff’s alpha(a)from weighted kappa statistics.RESULTS N=145 patients with mean age of 60(SD:13 years.),39%females,and 40%with body mass index≥30 kg/m2 were included in the analysis.For identifying patients with NASH,MR liver fat and cT1 were the strongest performing individual measures(AUC:0.80 and 0.75 respectively),and the mpMRI metrics combined(cT1 and MR liver fat)were the overall best non-invasive test(AUC:0.83).For identifying fibrosis≥1,MRE performed best(AUC:0.97),compared to VCTE-liver stiffness measure(AUC:0.94)and 2D-SWE(AUC:0.94).For assessment of steatosis≥1,MR liver fat was the best performing non-invasive test(AUC:0.92),compared to controlled attenuated parameter(AUC:0.75).Assessment of the agreement between pathologists showed that concordance was best for steatosis(a=0.58),moderate for ballooning(a=0.40)and fibrosis(a=0.40),and worst for lobular inflammation(a=0.11).CONCLUSION Quantitative mpMRI is an effective alternative to liver biopsy for diagnosing NASH and non-alcoholic fatty liver,and thus may offer clinical utility in patient management. 展开更多
关键词 Corrected T1 Fibro-inflammation Non-invasive imaging Non-alcoholic steatohepatitis Multiparametric magnetic resonance imaging Non-alcoholic fatty liver disease
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Three-dimensional time-of-flight magnetic resonance angiography combined with high resolution T2-weighted imaging in preoperative evaluation of microvascular decompression 被引量:1
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作者 Chen Liang Ling Yang +2 位作者 Bin-Bin Zhang Shi-Wen Guo Rui-Chun Li 《World Journal of Clinical Cases》 SCIE 2022年第34期12594-12604,共11页
BACKGROUND Neurovascular compression(NVC) is the main cause of primary trigeminal neuralgia(TN) and hemifacial spasm(HFS). Microvascular decompression(MVD) is an effective surgical method for the treatment of TN and H... BACKGROUND Neurovascular compression(NVC) is the main cause of primary trigeminal neuralgia(TN) and hemifacial spasm(HFS). Microvascular decompression(MVD) is an effective surgical method for the treatment of TN and HFS caused by NVC. The judgement of NVC is a critical step in the preoperative evaluation of MVD, which is related to the effect of MVD treatment. Magnetic resonance imaging(MRI) technology has been used to detect NVC prior to MVD for several years. Among many MRI sequences, three-dimensional time-of-flight magnetic resonance angiography(3D TOF MRA) is the most widely used. However, 3D TOF MRA has some shortcomings in detecting NVC. Therefore, 3D TOF MRA combined with high resolution T2-weighted imaging(HR T2WI) is considered to be a more effective method to detect NVC.AIM To determine the value of 3D TOF MRA combined with HR T2WI in the judgment of NVC, and thus to assess its value in the preoperative evaluation of MVD.METHODS Related studies published from inception to September 2022 based on PubMed, Embase, Web of Science, and the Cochrane Library were retrieved. Studies that investigated 3D TOF MRA combined with HR T2WI to judge NVC in patients with TN or HFS were included according to the inclusion criteria. Studies without complete data or not relevant to the research topics were excluded. The Quality Assessment of Diagnostic Accuracy Studies checklist was used to assess the quality of included studies. The publication bias of the included literature was examined by Deeks’ test. An exact binomial rendition of the bivariate mixed-effects regression model was used to synthesize data. Data analysis was performed using the MIDAS module of statistical software Stata 16.0. Two independent investigators extracted patient and study characteristics, and discrepancies were resolved by consensus. Individual and pooled sensitivities and specificities were calculated. The I_(2) statistic and Q test were used to test heterogeneity. The study was registered on the website of PROSERO(registration No. CRD42022357158).RESULTS Our search identified 595 articles, of which 12(including 855 patients) fulfilled the inclusion criteria. Bivariate analysis showed that the pooled sensitivity and specificity of 3D TOF MRA combined with HR T2WI for detecting NVC were 0.96 [95% confidence interval(CI): 0.92-0.98] and 0.92(95%CI: 0.74-0.98), respectively. The pooled positive likelihood ratio was 12.4(95%CI: 3.2-47.8), pooled negative likelihood ratio was 0.04(95%CI: 0.02-0.09), and pooled diagnostic odds ratio was 283(95%CI: 50-1620). The area under the receiver operating characteristic curve was 0.98(95%CI: 0.97-0.99). The studies showed no substantial heterogeneity(I2 = 0, Q = 0.001 P = 0.50).CONCLUSION Our results suggest that 3D TOF MRA combined with HR T2WI has excellent sensitivity and specificity for judging NVC in patients with TN or HFS. This method can be used as an effective tool for preoperative evaluation of MVD. 展开更多
关键词 Three-dimensional time-of-flight magnetic resonance angiography High resolution T2 weighted imaging Neurovascular compression Microvascular decompression META-ANALYSIS
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不同节段直肠癌T分期的多模态1.5T MRI评估与病理对照研究
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作者 刘业培 王园园 +2 位作者 李志湄 焦洪斌 李美玲 《中国CT和MRI杂志》 2024年第4期137-140,共4页
目的探讨分析多模态1.5T磁共振成像(MRI)对不同节段直肠癌T分期的评估价值。方法选取我院2018年6月至2023年3月收治的经肠镜下活检确诊的160例直肠癌患者作为研究对象,所有患者术前均进行多模态1.5T MRI检查,并接受全直肠系膜切除术(TME... 目的探讨分析多模态1.5T磁共振成像(MRI)对不同节段直肠癌T分期的评估价值。方法选取我院2018年6月至2023年3月收治的经肠镜下活检确诊的160例直肠癌患者作为研究对象,所有患者术前均进行多模态1.5T MRI检查,并接受全直肠系膜切除术(TME)治疗及术后病理分析,以病理结果为金指标,分析1.5T MRI对直肠癌T分期的评估价值;依据肠镜测量的肿瘤距肛门距离将全部患者分为低位直肠癌、中位直肠癌、高位直肠癌,分析多模态1.5T MRI检查对不同节段直肠癌T分期的评估价值及效能分析。结果1.5T MRI分期的评估准确率为89.38%;MRI T_(1)分期的准确率、敏感性、特异性、阳性预测值及阴性预测值分别为98.75%、94.74%、100.00%、100.00%、98.39%;T2分期的各项评估结果分别为91.25%、86.49%、92.68%、78.05%、95.80%;T3分期的各项评估结果分别为90.63%、75.61%、95.80%、86.11%、91.94%;T4分期的各项评估结果分别为100.00%、100.00%、97.48%、93.62%、100.00%;1.5T MRI低位及中位直肠癌T_(1)分期的准确率、特异性及阳性预测值最高,T4分期的敏感性及阴性预测值最高;高位直肠癌T_(1)分期的的评估准确率、敏感性、特异性及阴性预测值,T4分期的敏感性及阴性预测值最高;且三个阶段其他T分期的各项效能分析均较高。结论1.5T MRI评估效果显著,且对于直肠癌患者T分期的各项效能指标评估分析参考价值都较高,有更为准确的评估结果,值得临床上使用推广。 展开更多
关键词 直肠癌 1.5t磁共振成像 低位直肠癌 中位直肠癌 高位直肠癌 T分期
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3.0 Tesla magnetic resonance imaging: A new standard in liver imaging?
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作者 Rossano Girometti 《World Journal of Hepatology》 CAS 2015年第15期1894-1898,共5页
An ever-increasing number of 3.0 Tesla(T) magnets are installed worldwide. Moving from the standard of 1.5 T to higher field strength implies a number of potential advantage and drawbacks, requiring careful optimizati... An ever-increasing number of 3.0 Tesla(T) magnets are installed worldwide. Moving from the standard of 1.5 T to higher field strength implies a number of potential advantage and drawbacks, requiring careful optimization of imaging protocols or implementation of novel hardware components. Clinical practice and literature review suggest that state-of-the-art 3.0 T is equivalent to 1.5 T in the assessment of focal liver lesions and diffuse liver disease. Therefore, further technical improvements are needed in order to fully exploit the potential of higher field strength. 展开更多
关键词 magnetic resonance imaging LIVER 1.5tesla 3.0 TESLA magnetic field STRENGTH
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Linear-fitting-based similarity coefficient map for tissue dissimilarity analysis in T2^*-w magnetic resonance imaging
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作者 余绍德 伍世宾 +5 位作者 王浩宇 魏新华 陈鑫 潘万龙 Hu Jiani 谢耀钦 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第12期610-615,共6页
Similarity coefficient mapping(SCM) aims to improve the morphological evaluation of T*2weighted magnetic resonance imaging(T*2-w MRI). However, how to interpret the generated SCM map is still pending. Moreover, ... Similarity coefficient mapping(SCM) aims to improve the morphological evaluation of T*2weighted magnetic resonance imaging(T*2-w MRI). However, how to interpret the generated SCM map is still pending. Moreover, is it probable to extract tissue dissimilarity messages based on the theory behind SCM? The primary purpose of this paper is to address these two questions. First, the theory of SCM was interpreted from the perspective of linear fitting. Then, a term was embedded for tissue dissimilarity information. Finally, our method was validated with sixteen human brain image series from multiecho T*2-w MRI. Generated maps were investigated from signal-to-noise ratio(SNR) and perceived visual quality, and then interpreted from intra- and inter-tissue intensity. Experimental results show that both perceptibility of anatomical structures and tissue contrast are improved. More importantly, tissue similarity or dissimilarity can be quantified and cross-validated from pixel intensity analysis. This method benefits image enhancement, tissue classification, malformation detection and morphological evaluation. 展开更多
关键词 T*2-w magnetic resonance imaging similarity coefficient map linear fitting tissue dissimilarity
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Feasibility of imaging superficial palmar arch using microultrasound,7T and 3T magnetic resonance imaging
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作者 Alison N Pruzan Audrey E Kaufman +3 位作者 Claudia Calcagno Yu Zhou Zahi A Fayad Venkatesh Mani 《World Journal of Radiology》 CAS 2017年第2期79-84,共6页
AIM To demonstrate feasibility of vessel wall imaging of the superficial palmar arch using high frequency microultrasound, 7T and 3T magnetic resonance imaging(MRI).METHODS Four subjects(ages 22-50 years) were scanned... AIM To demonstrate feasibility of vessel wall imaging of the superficial palmar arch using high frequency microultrasound, 7T and 3T magnetic resonance imaging(MRI).METHODS Four subjects(ages 22-50 years) were scanned on a micro-ultrasound system with a 45-MHz transducer(Vevo 2100, Visual Sonics). Subjects' hands were then imaged on a 3T clinical MR scanner(Siemens Biograph MMR) using an 8-channel special purpose phased array carotid coil. Lastly, subjects' hands were imaged on a 7T clinical MR scanner(Siemens Magnetom 7T Whole Body Scanner) using a custom built 8-channel transmit receive carotid coil. All three imaging modalities were subjectively analyzed for image quality and visualization of the vessel wall. RESULTS Results of this very preliminary study indicated that vessel wall imaging of the superficial palmar arch was feasible with a whole body 7T and 3T MRI in comparison with micro-ultrasound. Subjective analysis of image quality(1-5 scale, 1: poorest, 5: best) from B mode, ultrasound, 3T SPACE MRI and 7T SPACE MRI indicated that the image quality obtained at 7T was superior to both 3T MRI and micro-ultrasound. The 3D SPACE sequence at both 7T and 3T MRI with isotropic voxels allowed for multi-planarreformatting of images and allowed for less operator dependent results as compared to high frequency microultrasound imaging. Although quantitative analysis revealed that there was no significant difference between the three methods, the 7T Tesla trended to have better visibility of the vessel and its wall. CONCLUSION Imaging of smaller arteries at the 7T is feasible for evaluating atherosclerosis burden and may be of clinical relevance in multiple diseases. 展开更多
关键词 Superficial Palmar Arch 7T and 3T magnetic resonance imaging Micro-ultrasound ATHEROSCLEROSIS Cardiovascular disease
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Patient’s Comfort and Technical Quality Exams at 1.5 and 3.0 T Magnetic Resonance Imaging
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作者 Siniša Vujmilović Saša Vujnović +3 位作者 Violeta Kovačević-Dragosavljević Zoran Vujković Davorka Katana Dragana Grujić-Vujmilović 《Open Journal of Radiology》 2016年第4期264-274,共11页
Increased interest of clinicians for using 3.0 T magnetic resonance imaging (MRI), as imaging modality of choice for their patients, has been evident in the past few years. The aim of this study was to compare the tec... Increased interest of clinicians for using 3.0 T magnetic resonance imaging (MRI), as imaging modality of choice for their patients, has been evident in the past few years. The aim of this study was to compare the technical quality of the obtained tomography using 3.0 T and 1.5 T MRI, and to compare the subjective feeling of discomfort of patients and subjective acoustic noise experience during imaging using MRI at 3.0 T and 1.5 T. Brain MRI (1.5 and 3.0 T) was performed in 58 patients, according to a standardized protocol. All studies have been randomly described by independent two radiologists. The reference standard for the existence of technical artifact is established on the basis of both radiologists’ consensus. We also compared the subjective feelings of the discomfort and acoustic noise during the both MRI (1.5 T and 3.0 T) exams. Artifacts were significantly more common during 3.0 T MRI in comparison with the 1.5 T MRI (χ2 = 5.286, P < 0.05), as well as in male patients (χ2 = 8.841, P < 0.05), and sub-jective assessments of discomfort and acoustic noise were higher in patients who underwent imaging using 3.0 T MRI, (χ2 = 125.959, df = 1, P < 0.001) and in females (χ2 = 195.449, df = 1, P < 0.001). Additional research is needed to prove that appropriate information for patients about the discomfort during 3.0 T MRI and their psychological preparation is very important element for optimal use of 3.0 T MRI in daily clinical practice. 展开更多
关键词 magnetic resonance imaging (MRI) 3.0 T ARTIFACTS Acoustic Noise DISCOMFORT COMFORT
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The Diagnostic Value of Brain Magnetic Resonance Imaging in Detecting CNS Diseases Among Advanced AIDS Patients
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作者 Fang Zhao Li-qing Sun +5 位作者 Yi-mei Tian Liu-mei Xu Pu-xuan Lu Xian Tang Ying-xia Liu Hui Wang 《国际感染病学(电子版)》 CAS 2014年第4期173-178,共6页
Objective To investigate the diagnostic value of brain magnetic resonance imaging in detecting central nervous system diseases among AIDS patients of different levels of T cells. Methods Total of 164 AIDS patients who... Objective To investigate the diagnostic value of brain magnetic resonance imaging in detecting central nervous system diseases among AIDS patients of different levels of T cells. Methods Total of 164 AIDS patients who did not receive antiviral treatment were divided into 2 groups according to their baseline CD4+ T cell counts. Group A had CD4+ T cell below or equal to 50 cells/μl(n = 81) and group B had CD4+ T cells over 50 cells/μl(n = 83). All patients underwent brain MRI scan. Imaging analysis and the prevalence of the central nervous system disorders were compared between two groups. Results Among them 48 cases were found of abnormal brain MRI, group A was higher than group B(35.8% vs. 22.9%) although without statistical significance(P = 0.065). Altogether 48 cases were diagnosed as AIDS related central nervous system disorders based on clinical symptoms, signs and laboratory findings. The prevalence of CNS disorders was higher in group A than in group B(41.9% vs. 16.8%) with statistical significance(P < 0.01). Conclusions The patients with CD4+ T cell count less than or equal to 50 cells/μl had high prevalence of CNS diseases. Brain MRI plays an important role in the diagnosis and differentiation of CNS diseases in advanced AIDS patients. This study suggests patients with low CD4+ T cell count(≤ 50/μl) should routinely undergo MRI examination. 展开更多
关键词 Central nervous system Intracranial diseases CD4+ T cell magnetic resonance imaging
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7T超高场磁共振颅内血管壁成像在缺血性脑卒中病因分型中的研究进展
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作者 张强 许晓泉 吴飞云 《磁共振成像》 CAS CSCD 北大核心 2024年第9期157-161,共5页
缺血性脑卒中的病因分型对临床治疗决策和预后判断有重要价值。近年来,随着高分辨率磁共振血管壁成像(high-resolution vessel wall magnetic resonance imaging,HR-VW-MRI)在脑卒中临床研究和实践中的应用增加,7 T MRI以其更高信噪比... 缺血性脑卒中的病因分型对临床治疗决策和预后判断有重要价值。近年来,随着高分辨率磁共振血管壁成像(high-resolution vessel wall magnetic resonance imaging,HR-VW-MRI)在脑卒中临床研究和实践中的应用增加,7 T MRI以其更高信噪比和更优图像质量,可发现脑血管早期、细微的病理变化,为深入了解各种脑血管疾病的病理机制提供了新思路。然而,超高场强也存在B1场不均、扫描时间长等技术挑战。本文就7 T HR-VW-MRI在缺血性卒中病因分型及临床应用中的进展进行综述,深入分析7 T HR-VW-MRI在提升临床诊断精确性与指导临床治疗中的潜在价值,为临床实践与科研探索提供参考。 展开更多
关键词 缺血性脑卒中 7 T 超高场 高分辨率磁共振血管壁成像 磁共振成像
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飞利浦Ingenia 3.0 T磁共振成像仪射频系统故障三例
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作者 邵晓宁 吕佩颖 +1 位作者 刘良 程敬亮 《中国医疗设备》 2024年第6期178-182,共5页
磁共振成像无电离辐射且软组织成像效果较好,已成为常规体检和疾病诊断非常重要的医学影像诊疗技术之一。磁共振设备结构复杂,维修及维护成本较高,长期高负荷的运转会导致磁共振设备故障率增加。本文总结了本院飞利浦Ingenia 3.0 T磁共... 磁共振成像无电离辐射且软组织成像效果较好,已成为常规体检和疾病诊断非常重要的医学影像诊疗技术之一。磁共振设备结构复杂,维修及维护成本较高,长期高负荷的运转会导致磁共振设备故障率增加。本文总结了本院飞利浦Ingenia 3.0 T磁共振设备射频系统故障三例,包括de-tuned印刷电路板故障、射频放大器故障及体线圈故障。文中对三例飞利浦磁共振设备射频系统故障的表现进行了描述,对故障产生的原因进行了分析并介绍了故障排除过程,包括观察外观、提取后台日志参数、测量疑似受损部件指标、更换受损部件以及系统测试。通过深入分析射频系统故障案例,分享维修经验,以期提高设备使用率。 展开更多
关键词 3.0 T磁共振成像仪 射频系统 射频放大器 体线圈
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大数据画像结合多种教学方法在医学影像技术专业磁共振实习中的应用
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作者 翟方兵 刘亚洁 +2 位作者 赖声远 杨俊武 卢洋 《中国继续医学教育》 2024年第16期37-41,共5页
磁共振实习一直是医学影像技术专业学生实习的难点,各教学基地对于如何提高磁共振实习质量仍处于探索阶段。文章针对学生实习过程中的困惑、磁共振实习阶段存在问题,提出大数据画像结合多种教学方法,构建医学影像技术专业学生在磁共振... 磁共振实习一直是医学影像技术专业学生实习的难点,各教学基地对于如何提高磁共振实习质量仍处于探索阶段。文章针对学生实习过程中的困惑、磁共振实习阶段存在问题,提出大数据画像结合多种教学方法,构建医学影像技术专业学生在磁共振实习中的大数据画像模型,详细阐述实施计划及设计流程并对实行此项教学改革的显著效果进行了分析与总结。此项教学改革有效避免了传统实习模式的固化形式,对学生进行因材施教精准培养的同时可提高教师自身专业水平,实现了师生双方的共同成长,为医学影像技术专业学生实习培养提供了新的思路和方法,为培养出更多优秀的毕业生奠定坚实的基础。 展开更多
关键词 大数据画像 医学影像技术实习 磁共振实习教学查房 多种教学方法融合 医学生实习预警机制 医学生精准培养
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提高医学影像技术专业进修生CMR扫描技术的教学方法及思考
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作者 陶黎 徐勇 《继续医学教育》 2024年第5期127-130,共4页
在重庆医科大学附属第一医院金山院区进行的心脏磁共振(cardiovascular magnetic resonance,CMR)扫描技术短期进修中,医学影像技术专业的进修生遇到了几个主要问题:不熟悉扫描流程、扫描序列的功能及其参数设置,以及对常见心脏病诊断的... 在重庆医科大学附属第一医院金山院区进行的心脏磁共振(cardiovascular magnetic resonance,CMR)扫描技术短期进修中,医学影像技术专业的进修生遇到了几个主要问题:不熟悉扫描流程、扫描序列的功能及其参数设置,以及对常见心脏病诊断的理解不全面,导致无法有效处理扫描过程中的参数冲突。此外,进修生迫切希望能在短时间内掌握扫描技术,以便回归工作岗位时应用所学知识。针对上述问题和需求,笔者提出了一套教学改进措施,包括针对扫描技术规范、扫描序列及其参数特性的详细讲解,解决扫描过程中的参数冲突的策略,以及常见心脏病诊断的关键点。教学中采用了理论与实践相结合的方法,使进修生能在短期内有效掌握CMR扫描技术。通过这种教学方法,进修生不仅在短暂的学习期间基本掌握了CMR扫描技术,回到各自单位后,也能够独立开展相关技术项目,显著提高了进修生的技术掌握度和满意度。 展开更多
关键词 影像技术 进修生 心脏磁共振 满意度 教学改革 继续医学教育
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不同功能磁共振成像技术在乳腺癌中的应用进展 被引量:3
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作者 冯雯 刘欣然 +1 位作者 卢星如 雷军强 《磁共振成像》 CAS CSCD 北大核心 2024年第1期217-223,共7页
乳腺癌成为全球第一大癌症,充分了解不同功能MRI技术在乳腺癌中的应用有利于推进乳腺癌诊疗的发展。本文通过介绍不同功能MRI技术在乳腺癌早期诊断和晚期预后评估中展现出的临床科研价值,说明基于灌注、代谢、扩散、合成相关MRI,使肿瘤... 乳腺癌成为全球第一大癌症,充分了解不同功能MRI技术在乳腺癌中的应用有利于推进乳腺癌诊疗的发展。本文通过介绍不同功能MRI技术在乳腺癌早期诊断和晚期预后评估中展现出的临床科研价值,说明基于灌注、代谢、扩散、合成相关MRI,使肿瘤组织微血管渗透、分布、血流动力学状态,肿瘤代谢物含量、间质成分变化及组织固有属性等特征可视化,旨在总结各成像序列在乳腺癌应用中的优势和前景,以期为后续乳腺癌影像科学研究提供新方向,从而帮助影像医师更加全面地了解乳腺癌相关MRI技术手段。 展开更多
关键词 乳腺癌 多模态 磁共振成像 功能磁共振成像 合成磁共振成像 影像学技术
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基于两种Dixon技术的乳腺磁共振T2WI序列图像质量对比研究 被引量:1
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作者 蒋平平 陈燕清 +3 位作者 黄涛 官晓晖 陆虹宇 邓德茂 《磁共振成像》 CAS CSCD 北大核心 2024年第3期158-162,共5页
目的 对比分析乳腺MRI T2WI序列中双回波快速水脂分离(Fast Dixon)技术与传统两点法水脂分离(Dixon)技术图像质量,探讨两种Dixon技术的临床应用价值。材料与方法 回顾性分析2022年6月至2023年3月广西壮族自治区人民医院同时行Fast Dixon... 目的 对比分析乳腺MRI T2WI序列中双回波快速水脂分离(Fast Dixon)技术与传统两点法水脂分离(Dixon)技术图像质量,探讨两种Dixon技术的临床应用价值。材料与方法 回顾性分析2022年6月至2023年3月广西壮族自治区人民医院同时行Fast Dixon(Fast Dixon组)与两点Dixon(两点Dixon组)两种脂肪抑制T2WI序列的41例乳腺MRI检查女性患者病例。综合分析两组图像的质量(包括总体图像质量、脂肪抑制质量、纤维腺体组织与实性病灶的清晰度及在腋窝、胸壁、皮肤区域的运动伪影大小);计算病灶、腋窝、胸肌、正常实质的信噪比(signal-to-noise ratio,SNR)及病灶实质对比噪声比(contrast-to-noise ratio,CNR)。采用Kendall’s W系数评估观察者间主观评分数据的一致性,采用组内相关系数(intra-class correlation coefficient,ICC)评价观察者间图像质量客观定量评价参数的一致性。计数资料用非参数检验进行比较,计量资料采用配对t检验或Wilcoxon符号秩检验。P<0.05为差异有统计学意义。结果 主观评价:两名医师主观评分一致性较好或极好(Kendall’s W=0.773~0.928,P<0.001);两种Dixon技术均可获得均匀一致的脂肪抑制图像质量(P>0.05);Fast Dixon组在腋窝、胸壁、皮肤区域运动伪影更小,总体图像质量较两点Dixon组好,差异有统计学意义(P<0.05);两组图像纤维腺体组织及病灶的清晰度差异无统计学意义(P>0.05)。客观评价:两名观察者观测值计算所得SNR和CNR具有极好的一致性(ICC=0.897~0.936,P<0.001);Fast Dixon组在病灶、正常实质、胸肌及腋窝的SNR优于两点Dixon组(P<0.05);两组病灶的CNR差异无统计学意义(P>0.05)。结论 与两点Dixon技术相比,Fast Dixon技术既可获得均匀一致的脂肪抑制图像,同时运动伪影较少,显著改善乳腺周围区域的图像质量,提升乳腺MRI T2WI序列总体图像质量。 展开更多
关键词 乳腺相关疾病 脂肪抑制 运动伪影 图像质量 水脂分离技术 T2加权成像 磁共振成像
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基于DWI的分形维数评价3D打印技术对胶质瘤术后临床疗效的价值
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作者 席华泽 景梦园 +5 位作者 柴彦军 赵志勇 袁隆 杨晶晶 徐敏 周俊林 《磁共振成像》 CAS CSCD 北大核心 2024年第4期32-37,44,共7页
目的使用基于弥散加权成像(diffusion weighted imaging,DWI)的分形维数(fractal dimension,FD)评价个性化3D打印技术是否可以提高手术治疗胶质瘤患者的临床疗效。材料与方法回顾性分析2018年1月至2023年1月我院经病理证实的136例胶质... 目的使用基于弥散加权成像(diffusion weighted imaging,DWI)的分形维数(fractal dimension,FD)评价个性化3D打印技术是否可以提高手术治疗胶质瘤患者的临床疗效。材料与方法回顾性分析2018年1月至2023年1月我院经病理证实的136例胶质瘤患者病例,其中32例为试验组,术前使用了个性化3D打印技术;其余患者为对照组,进行常规开颅手术。在术后一周DWI图上手动勾画术区周围边界,绘制二值图后测量FD。使用FD中位数对对照组进行分组,比较对照组中高FD和低FD患者的手术情况、疼痛程度、神经缺损程度、预后、日常生活能力是否存在差异;探究个性化3D打印技术是否会影响水肿创面的FD,以及是否会进一步提高患者临床疗效。结果高FD组的疼痛程度(t=−13.228,P<0.001)、神经缺损程度(t=−2.627,P=0.008)高于低FD组,日常生活能力(t=4.821,P<0.001)及预后(t=−3.058,P=0.003)较低FD组差。受试者工作特征(receiver operating characteristic,ROC)曲线结果显示FD能对患者上述四项评分的高低进行有效区分,术前使用个性化3D打印技术可使得患者水肿带FD下降,减轻神经缺损程度并提高日常生活能力,但对改善预后及术区疼痛效果不明显。结论个性化3D打印技术可以有效降低患者术区创面水肿带的FD,减轻神经损伤,值得临床应用。 展开更多
关键词 脑胶质瘤 弥散加权成像 磁共振成像 分形维数 3D打印技术 精准医疗
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磁共振多序列成像在结肠癌T分期中的诊断性能探究
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作者 于庆 杨春英 靳海英 《中国CT和MRI杂志》 2024年第9期137-139,共3页
目的探讨磁共振多序列成像(magnetic resonance imaging,MRI)在结肠癌(colon cancer,CC)T分期的诊断性能。方法回顾性收集河南大学淮河医院于2022年1月至2022年12月收治的结肠癌患者32例。所有结肠癌患者术前均接受MRI检查。依次使用T2... 目的探讨磁共振多序列成像(magnetic resonance imaging,MRI)在结肠癌(colon cancer,CC)T分期的诊断性能。方法回顾性收集河南大学淮河医院于2022年1月至2022年12月收治的结肠癌患者32例。所有结肠癌患者术前均接受MRI检查。依次使用T2加权成像快速自旋回波序列(T2 weighted imaging,T2WI)快速自旋回波序列(冠状面、轴面、矢状面)、扩散加权成像序列(diffusion weighted imaging,DWI)序列(轴面)及对比增强T1加权成像(T1 weighted imaging,T1WI)序列(冠状面)完成对全腹部和肝脏的扫描。分别对肿瘤的位置、肠壁浸润深度及是否侵犯浆膜层进行记录,并与术后病理结果进行比较。采用受试者工作(receiver operating characteristic,ROC)曲线分析MRI中T2WI序列、对比增强T1WI序列对术前CC患者T分期的诊断效能。结果MRI中T2WI序列对结肠癌患者T分期的准确性、敏感性、特异性分别为81.25%,84.21%,66.67%。此外,MRI中增强T1WI序列的准确性、敏感性、特异性分别为93.75%,94.12%,75%。结论MRI是结肠癌患者术前T分期检测的一种潜在的和有价值的影像学方法,且T1WI具有更高的诊断价值。 展开更多
关键词 结肠癌 核磁共振成像 T分期
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CMR特征追踪技术在帕金森病患者左心评估中的价值
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作者 岳汛 刘铃 +7 位作者 彭鹏飞 蒲倩 杨慧义 明悦 岳书婷 黄小华 徐严明 孙家瑜 《磁共振成像》 CAS CSCD 北大核心 2024年第3期74-80,共7页
目的应用心脏磁共振特征追踪(cardiac magnetic resonance feature tracking,CMR-FT)技术评估帕金森病(Parkinson’s disease,PD)患者的左心结构和功能,并探讨影响其结构和功能的因素。材料与方法前瞻性纳入2022年3月至2023年8月于四川... 目的应用心脏磁共振特征追踪(cardiac magnetic resonance feature tracking,CMR-FT)技术评估帕金森病(Parkinson’s disease,PD)患者的左心结构和功能,并探讨影响其结构和功能的因素。材料与方法前瞻性纳入2022年3月至2023年8月于四川大学华西医院就诊的PD患者(PD组)39例,同期招募年龄及性别匹配的健康对照者(对照组)34例,均完成常规心脏磁共振(cardiac magnetic resonance,CMR)检查。使用专业后处理软件CVI42分别获得左心室及左心房的常规心功能及心肌应变参数。左心室参数包括:收缩末期容积、舒张末期容积、心肌质量、射血分数、整体周向、径向及纵向应变。左心房参数包括:储备期、导管期及泵血期的射血分数、容积、应变及应变率。采用独立样本t检验或Mann-Whitney U检验分析各参数的组间差异。采用Pearson或Spearman相关系数模型分析常规心功能及应变参数与运动功能及自主神经功能的相关性。结果PD组相较于对照组,左室射血分数[(62.01±6.59)%vs.(64.84±4.70)%]及整体的纵向应变[(-17.25±1.57)%vs.(-18.28±1.99)%]均较低(P均<0.05)。PD组相较于对照组,左心室收缩末期容积(left ventricular end-systolic volume,LVESV)[(51.17±16.56)mL vs.(42.56±9.06)mL]、LVESV指数(LVESV index,LVESVi)[(30.44±8.00)mL·m^(-2)vs.(25.56±5.14)m L·m^(-2)]、左心室舒张末期容积指数(left ventricular end-diastolic volume index,LVEDVi)[(79.31±10.76)m L·m^(-2)vs.(72.97±12.51)mL·m^(-2)]及左心室心肌质量指数(left ventricular mass index,LV massi)[41.82(33.11,47.77)g·m^(-2)vs.33.71(32.27,38.78)g·m^(-2)]均较高(P<0.05)。PD组的左心房储备期、导管期及泵血期的射血分数、应变及应变率较对照组明显减低(P均<0.05)。相关性分析显示,左心房储备期应变及应变率与统一帕金森评定量表Ⅲ(Unified Parkinson’s Disease Rating ScaleⅢ,UPDRSⅢ)评分呈负相关(r=-0.409、-0.355,P<0.05)。左心房导管期射血分数、应变与UPDRSⅢ评分呈负相关(r=-0.326、-0.482,P<0.05)、应变率与UPDRSⅢ评分呈正相关(r=0.417,P=0.008)。左心房储备期应变、应变率与自主神经症状自评量表(The Scales for Outcomes in Parkinson’s Disease-Autonomic,SCOPA-AUT)评分呈负相关(r=-0.535、-0.319,P均<0.05)。左心房导管期应变与SCOPA-AUT评分呈负相关(r=-0.319,P=0.048),应变率与SCOPA-AUT评分呈正相关(r=0.359,P=0.025)。左心房泵血期应变与SCOPA-AUT呈负相关(r=-0.342,P=0.033)。结论CMR-FT获得的应变及应变率参数可早期评估PD患者的心功能受损程度。PD患者左室收缩功能及左心房储备、导管、泵功能受损;左心房储备功能及导管功能与运动功能障碍及自主神经功能障碍的严重程度相关。 展开更多
关键词 帕金森病 心脏磁共振 特征追踪技术 心肌应变 左心 磁共振成像
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