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Predictors of short-term outcome in patients with acute middle cerebral artery occlusion: unsuitability of fluid-attenuated inversion recovery vascular hyperintensity scores 被引量:13
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作者 Chan-chan Li Xiao-zhu Hao +3 位作者 Jia-qi Tian Zhen-wei Yao Xiao-yuan Feng Yan-mei Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第1期69-76,共8页
Fluid-attenuated inversion recovery (FLAIR) vascular hyperintensity (FVH) is used to assess leptomeningeal collateral circulation, but clinical outcomes of patients with FVH can be very different. The aim of the p... Fluid-attenuated inversion recovery (FLAIR) vascular hyperintensity (FVH) is used to assess leptomeningeal collateral circulation, but clinical outcomes of patients with FVH can be very different. The aim of the present study was to assess a FVH score and explore its relationship with clinical outcomes. Patients with acute ischemic stroke due to middle cerebral artery M1 occlusion underwent magnetic resonance imaging and were followed up at 10 days (National Institutes of Health Stroke Scale) and 90 days (modified Rankin Scale) to determine short-term clinical outcomes. Effective collateral circulation indirectly improved recovery of neurological function and short-term clinical outcome by extending the size of the pial penumbra and reducing infarct lesions. FVH score showed no correlation with 90-day functional clinical outcome and was not sufficient as an independent predictor of short-term clinical outcome. 展开更多
关键词 nerve regeneration National Institutes of Health Stroke Scale middle cerebral artery occlusion collateral circulation modified Rankin Scale score cerebral ischemia acute stroke diffusion-weighted imaging fluid-attenuated inversion recovery neural regeneration
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Early Diagnosis of Recurrent Optic Neuritis Using Contrast-Enhanced T2 Fluid-attenuated Inversion Recovery Imaging:a Case Report 被引量:4
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作者 Lihui Li Houbin Huang Zhiye Chen 《Chinese Medical Sciences Journal》 CAS CSCD 2018年第2期130-134,共5页
The diagnosis of the recurrent optic neuritis is commonly established clinically,and sometimes it could be challenging because the involved optic nerve does not always show significant enhancement on conventional cont... The diagnosis of the recurrent optic neuritis is commonly established clinically,and sometimes it could be challenging because the involved optic nerve does not always show significant enhancement on conventional contrast enhanced-T1 weighted imaging(CE-T1W1).In this paper,we reported a middle-aged female with early diagnosis of recurrent optic neuritis using contrast-enhanced T2 fluid-attenuated inversion recovery imaging(CET2FLAIR).The involved optic nerve presented evident enhancement on CE-T2FLAIR and no enhancement on CE-T1W1.This case suggested that the CE-T2FLAIR may be a useful diagnostic tool specifically for the recurrent optic neuritis in clinical practice. 展开更多
关键词 T2 fluid-attenuated inversion recovery imaging magnetic resonance imaging optic neuritis
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Diffusion-weighted imaging and fluid-attenuated inversion recovery sequence in sporadic Creutzfeldt-Jakob disease:One-case report
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作者 Rosa Morabito Annalisa Baglieri +8 位作者 Rosella Ciurleo Francesco Corallo Rosaria De Luca Simona De Salvo Silvia Guerrera Francesca Timpano Maria Adele Marino Placido Bramanti Silvia Marino 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第29期2295-2297,共3页
The diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD) is extremely difficult. Diffusion-weighted imaging has been shown to be the most sensitive technique for the detection of signal alterations in sCJD patient... The diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD) is extremely difficult. Diffusion-weighted imaging has been shown to be the most sensitive technique for the detection of signal alterations in sCJD patients. The present study analyzed the diagnostic value of diffusion-weighted imaging and fluid-attenuated inversion recovery sequence in the early stage of sCJD in one female patient and correlated the clinical symptoms during disease course and magnetic resonance manifestations. Thalamic and basal ganglia hyperintensities were observed on magnetic resonance images in a very early stage, i.e., when the clinical typical manifestations of the disease were not present. With the progression of the disease, cortical and basal ganglia hyperintensities were observed on magnetic resonance images, showing an obvious cerebral atrophy. These findings suggest that diffusion-weighted imaging and fluid-attenuated inversion recovery sequence are helpful in diagnosing sCJD. 展开更多
关键词 Creutzfeldt-Jacob disease fluid-attenuated inversion recovery diffusion-weighted imaging magnetic resonance imaging
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Three-dimensional gravity inversion based on sparse recovery iteration using approximate zero norm 被引量:6
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作者 Meng Zhao-Hai Xu Xue-Chun Huang Da-Nian 《Applied Geophysics》 SCIE CSCD 2018年第3期524-535,共12页
This research proposes a novel three-dimensional gravity inversion based on sparse recovery in compress sensing. Zero norm is selected as the objective function, which is then iteratively solved by the approximate zer... This research proposes a novel three-dimensional gravity inversion based on sparse recovery in compress sensing. Zero norm is selected as the objective function, which is then iteratively solved by the approximate zero norm solution. The inversion approach mainly employs forward modeling; a depth weight function is introduced into the objective function of the zero norms. Sparse inversion results are obtained by the corresponding optimal mathematical method. To achieve the practical geophysical and geological significance of the results, penalty function is applied to constrain the density values. Results obtained by proposed provide clear boundary depth and density contrast distribution information. The method's accuracy, validity, and reliability are verified by comparing its results with those of synthetic models. To further explain its reliability, a practical gravity data is obtained for a region in Texas, USA is applied. Inversion results for this region are compared with those of previous studies, including a research of logging data in the same area. The depth of salt dome obtained by the inversion method is 4.2 km, which is in good agreement with the 4.4 km value from the logging data. From this, the practicality of the inversion method is also validated. 展开更多
关键词 THREE-DIMENSIONAL gravity inversion sparse recovery APPROXIMATE ZERO NORM iterative method density constraint PENALTY function
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Optimized cardiac magnetic resonance imaging inversion recovery sequence for metal artifact reduction and accurate myocardial scar assessment in patients with cardiac implantable electronic devices 被引量:2
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作者 El-Sayed H Ibrahim Mason Runge +6 位作者 Jadranka Stojanovska Prachi Agarwal Maryam Ghadimi-Mahani Anil Attili Thomas Chenevert Chiel den Harder Frank Bogun 《World Journal of Radiology》 CAS 2018年第9期100-107,共8页
Late gadolinium enhancement(LGE) cardiovascular magnetic resonance(CMR) is the gold standard for imaging myocardial viability.An important application of LGE CMR is the assessment of the location and extent of the myo... Late gadolinium enhancement(LGE) cardiovascular magnetic resonance(CMR) is the gold standard for imaging myocardial viability.An important application of LGE CMR is the assessment of the location and extent of the myocardial scar in patients with ventricular tachycardia(VT), which allows for more accurate identification of the ablation targets.However, a large percentage of patients with VT have cardiac implantable electronic devices(CIEDs), which is a relative contraindication for cardiac magnetic resonance imaging due to safety and image artifact concerns.Previous studies showed that these patients can be safely scanned on 1.5 T scanners provided that an adequate imaging protocol is adopted.Nevertheless, imaging patients with a CIED result in metal artifacts due to the strong frequency off-resonance effects near the device; therefore, the spins in the surrounding myocardium are not completely inverted, and thus give rise to hyperintensity artifacts.These artifacts obscure the myocardial scar tissue and limit the ability to study the correlation between the myocardial scar structure and the electro-anatomical map during catheter ablation.In this study, we developed a modified inversion recovery technique to alleviate the CIED-induced metal artifacts and improve the diagnostic image quality of LGE images in patients with CIEDs without increasing scan time or requiring additional hardware.The developed technique was tested in phantom experiments and in vivo scans, which showed its capability for suppressing the hyperintensity artifacts without compromising myocardium nulling in the resulting LGE images. 展开更多
关键词 Magnetic resonance IMAGING Heart LATE GADOLINIUM enhancement VIABILITY IMAGING inversion recovery CARDIAC IMPLANTABLE electronic devices
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Facile synthesis of chromium chloride/poly(methyl methacrylate) core/shell nanocapsules by inverse miniemulsion evaporation method and application as delayed crosslinker in secondary oil recovery
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作者 Jing-Yang Pu Keith P.Johnston +4 位作者 Ping-Keng Wu Muaaz Ahmad Ming-Liang Luo Na Zhang Ju-Tao He 《Petroleum Science》 SCIE EI CAS CSCD 2023年第1期396-406,共11页
Cr(III)ehydrolyzed polyacrylamide(HPAM)gels have been extensively studied as a promising strategy controlling waste water production for mature oilfields.However,the gelation time of the current technologies is not lo... Cr(III)ehydrolyzed polyacrylamide(HPAM)gels have been extensively studied as a promising strategy controlling waste water production for mature oilfields.However,the gelation time of the current technologies is not long enough for in-depth placement.In this study,we report a novel synthesis method to obtain chromium chloride/poly(methyl methacrylate)(PMMA)nanocapsules which can significantly delay the gelation of HPAM through encapsulating the chromium chloride crosslinker.The chromium chloride-loaded nanocapsules(CreNC)are prepared via a facile inverse miniemulsion evaporation method during which the hydrophobic PMMA polymers,pre-dispersed in an organic solvent,were carefully controlled to precipitate onto stable aqueous miniemulsion droplets.The stable aqueous nanodroplets(W)containing Cr(III)are dispersed in a mixture of organic solvent(O1)with PMMA and nonsolvent medium(O2)to prepare an inverse miniemulsion.With the evaporation of the O1,PMMA forms CreNCs around the aqueous droplets.The CreNCs are readily transferred into water from the organic nonsolvent phase.The CreNCs exhibit the tunable size(358-983 nm),Cr loading(7.1%-19.1%),and Cr entrapment efficiency(11.7%-80.2%),with tunable zeta potentials in different PVA solutions.The CreNCs can delay release of Cr(III)and prolong the gelation time of HPAM up to 27 days. 展开更多
关键词 NANOCAPSULES inverse miniemulsion evaporation Chromium chloride crosslinker HPAM gelation Secondary oil recovery
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Delay enhancement patterns in apical hypertrophic cardiomyopathy by phase-sensitive inversion recovery sequence 被引量:1
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作者 Zi-Yi Guo Jing Chen +6 位作者 Qi-Zhou Liang Hai-Yan Liao Shui-Xi Fu Qian-Yu Tang Cai-Xiang Chen Xiang-Jun Han Feng Gao 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2012年第10期828-830,共3页
Objective:Late gadolinium enhancement(LGE) patterns of cardiovascular magnetic resonance (CMR) relying on PSIR(phase-sensitive inversion recovery sequence) techniques had been used to determine the characteristics of ... Objective:Late gadolinium enhancement(LGE) patterns of cardiovascular magnetic resonance (CMR) relying on PSIR(phase-sensitive inversion recovery sequence) techniques had been used to determine the characteristics of LGE in apical hypertrophic cardiomyopathy(ApHCM). Methods:Forty patients pure ApHCM[age,(60.2±10.4) years,31 men]were enrolled.LGE images were acquired using PSIR,and analyzed using a 17-segment model.Summing the LGE areas in all short axis slices yielded the total volume of late enhancement,which was subsequently presented as a proportion of total LV myocardium(%LGE).Results:Mean maximal apical wall thickness was(17.9±2.3) mm,and mean left ventricular(LV) ejection fraction was(67.7±8.0)%.LGE was detected in 130 segments of 30 patients(75.0%),occupying(4.9±5.5)% of LV myocardium.LGE was mainly detected at the junction between left and right ventricles in 12(30%) and at the apex in 28(70%),although LGE-positive areas were widely distributed,and not limited to the apex.Focal LGE at the non-hypertrophic LV segments was found in some ApHCM patients,even without LGE of hypertrophied apical segments.Conclusions:LGE was frequently observed not only in the thickened apex of the heart but also in other LV segments,irrespective of the presence or absence of hypertrophy.The simple presence of LGE on CMR was not representative of adverse prognosis in this population. 展开更多
关键词 APICAL HYPERTROPHIC cardiomyopathy Cardiovascular magnetic resonance Late gadolinium ENHANCEMENT Phase-sensitive inversion recovery SEQUENCE
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内耳三维真实重建反转恢复成像与突发性聋预后
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作者 张呈辉 王伟韬 +2 位作者 任芳芳 冀少杰 周鼎坤 《中华耳科学杂志》 CSCD 北大核心 2024年第1期53-57,共5页
目的分析突发性聋(突聋)患者的内耳三维真实重建反转恢复(three dimensional real inversion recovery,3D Real IR)成像表现,探讨内耳不同信号强度与突聋预后的关系。方法选取2022年9月25日—2023年4月10日郑州大学第五附属医院耳鼻咽... 目的分析突发性聋(突聋)患者的内耳三维真实重建反转恢复(three dimensional real inversion recovery,3D Real IR)成像表现,探讨内耳不同信号强度与突聋预后的关系。方法选取2022年9月25日—2023年4月10日郑州大学第五附属医院耳鼻咽喉科住院治疗及门诊治疗的单侧突聋患者60例,按照听力曲线将患者分为低频下降型4例、高频下降型1例、平坦下降型34例和全聋型21例。由于平坦下降型和全聋型治疗方法一致,将平坦下降型和全聋型的55例患者按治疗有效与否分为无效组25例和有效组30例;按治疗前听力分级,分为轻度听力损失组11例、中度听力损失组7例、重度听力损失组16例和极重度听力损失组21例;根据听力下降与否分为患耳组55耳和健耳组55耳。比较患耳和健耳的耳蜗信号强度,并测量延髓信号强度,分别计算耳蜗/延髓(cochlea/medulla ratio,CM)比值,分析耳蜗信号强度与治疗结果之间关系。结果无效组CM比值明显高于治疗有效组,差异有统计学意义(P<0.001);患耳组与健耳组CM比值比较,差异有统计学意义(P<0.05)。轻度、中度、重度和极重度听力损失组患耳CM比值比较(2.57±3.02 vs 1.77±0.87 vs 2.04±1.98 vs 2.51±2.33),差异无统计学意义(F=0.304,P=0.823)。结论内耳3D Real IR可显示突聋患者血-迷路屏障通透性的改变,CM比值可以更精确了解突聋患者内耳受损的程度,CM比值大小与听力损失程度并不一致,可以单独作为一种判断突聋预后的因素。突聋患者CM比值高于1.58提示可能预后不良。 展开更多
关键词 突发性聋 内耳三维真实重建反转恢复成像 耳蜗/延髓比值 预后
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血-迷路屏障通透性与突聋发病机制及预后的关系:在3D real IR的发现
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作者 张呈辉 任芳芳 +2 位作者 王伟韬 郝芳 冀少杰 《听力学及言语疾病杂志》 CAS CSCD 北大核心 2024年第3期236-240,共5页
目的分析突聋患者的内耳钆造影MRI三维真实重建反转恢复(three dimensional real inversion recovery,3D real IR)成像上的表现,探讨血-迷路屏障的通透性与突聋发病机制及其预后的关系。方法对41例单侧突聋患者行内耳钆造影MRI,测量患... 目的分析突聋患者的内耳钆造影MRI三维真实重建反转恢复(three dimensional real inversion recovery,3D real IR)成像上的表现,探讨血-迷路屏障的通透性与突聋发病机制及其预后的关系。方法对41例单侧突聋患者行内耳钆造影MRI,测量患耳和健耳的耳蜗信号强度,并测量延髓信号强度,分别计算出耳蜗/延髓比值(cochlear/medulla ratio,CM ratio),以CM比值作为血-迷路屏障通透性的标志物,分析突聋患者患耳、健耳CM比值的不对称程度与疗效之间的关系。结果41例患者中,33例(80.48%)患耳的CM比值高于健耳,差异有统计学意义(P<0.05);患耳CM比值为健耳的1.5倍以下者18例,治疗有效率为77.78%(14/18);患侧CM比值不高于健侧者8例,治疗有效率为100%;达到健耳的1.5倍至1.75倍之间者7例,治疗有效率为100%(7/7);达到健耳的1.75倍至2.0倍之间者2例,治疗有效率为50%(1/2);达到健耳的2.0倍以上者14例,治疗有效率为14.28%(12/14);差异有统计学意义(P<0.05)。结论内耳3D Real IR可显示突聋患者血-迷路屏障通透性的改变,80.48%的突聋患者患侧耳蜗出现高信号,患耳CM比值达健耳的1.75倍以上者多数预后不良。 展开更多
关键词 突聋 血-迷路屏障通透性 内耳三维真实重建反转恢复成像 耳蜗/延髓比值 预后
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钆对比剂剂量对增强T2 FLAIR序列与增强T1WI序列脑转移瘤强化效果的影响及对比研究 被引量:1
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作者 曹明慧 苏赟 +3 位作者 苏卫锋 毛家骥 李韵华 沈君 《磁共振成像》 CAS CSCD 北大核心 2024年第1期152-157,共6页
目的 对比不同剂量钆对比剂注射后增强液体衰减反转恢复(contrast enhanced T2 fluid attenuated inversion recovery,CE-T2 FLAIR)序列与对比增强T1WI(contrast enhanced T1WI, CE-T1WI)上脑转移瘤的强化效果,探讨半剂量对比剂条件下CE... 目的 对比不同剂量钆对比剂注射后增强液体衰减反转恢复(contrast enhanced T2 fluid attenuated inversion recovery,CE-T2 FLAIR)序列与对比增强T1WI(contrast enhanced T1WI, CE-T1WI)上脑转移瘤的强化效果,探讨半剂量对比剂条件下CE-T2 FLAIR序列在脑转移瘤MRI检查的诊断价值。材料与方法 前瞻性纳入颅外原发恶性肿瘤经病理学明确诊断、脑转移瘤经病理或临床随访证实的患者30例,于3.0 T MRI设备行头颅MRI增强扫描,在常规平扫序列的基础上,行半剂量(0.05 mmol/kg)CE-T2 FLAIR和CE-T1WI扫描,随后分次补充钆对比剂达常规剂量(0.1 mmol/kg)后至双倍剂量(0.2 mmol/kg),在注射对比剂后均进行CE-T2 FLAIR和CE-T1WI扫描。由两位观察者对三次扫描的CE-T2 FLAIR和CE-T1WI图像进行客观测量。计算不同剂量条件下CE-T2 FLAIR和CE-T1WI图像的对比信噪比(contrast to noise ratio, CNR)、相对对比度(relative contrast, RC)及百分比增加(percentage increase, PI)。采用方差分析对客观测量结果进行组间比较,差异有统计学意义(P<0.05)时进行后续多重比较;采用t检验比较两组之间的差异。结果 两位观察者客观评分一致性良好。三组对比剂剂量下CE-T2 FLAIR图像间CNR值与RC值差异无统计学意义(P>0.05);与平扫T2 FLAIR相比,病灶PI增高,增强效果良好。三组对比剂剂量下CE-T1WI图像间CNR值与RC值差异有统计学意义(P<0.05),两两比较结果表明双倍剂量CE-T1WI图像上CNR值及RC值均明显大于半剂量组(P<0.05)。半剂量及常规剂量CE-T2 FLAIR图像CNR值及RC值上均较该组CE-T1WI明显增大,差异有统计学意义(P<0.05)。半剂量CE-T2 FLAIR图像CNR值及RC值均明显大于常规剂量CE-T1WI(P<0.05)。与双倍剂量CE-T1WI相比,半剂量CE-T2 FLAIR图像CNR值增大(P<0.05),RC值差异无统计学意义(P>0.05)。结论 半剂量对比剂下CE-T2FLAIR图像上脑转移瘤的强化效果与常规CE-T1WI相仿,病灶显示良好,为半剂量对比剂的CE-T2 FLAIR序列应用于脑转移瘤MRI检查提供依据。 展开更多
关键词 脑转移瘤 磁共振成像 液体衰减反转恢复序列 半剂量钆对比剂 对比增强
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骨质疏松椎体骨折磁共振STIR信号改变与CT骨折线类型的关系 被引量:1
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作者 刘愉勤 刘英 +2 位作者 李兰 张滔 罗晓玲 《实用临床医药杂志》 CAS 2024年第5期21-24,共4页
目的探讨骨质疏松椎体骨折磁共振(MRI)-短反转时间反转恢复序列(STIR)信号改变与电子计算机断层扫描(CT)骨折线类型的关系。方法回顾性分析收治的108例骨质疏松椎体骨折患者临床资料以及MRI、CT影像学征象。比较不同MRI-STIR信号改变患... 目的探讨骨质疏松椎体骨折磁共振(MRI)-短反转时间反转恢复序列(STIR)信号改变与电子计算机断层扫描(CT)骨折线类型的关系。方法回顾性分析收治的108例骨质疏松椎体骨折患者临床资料以及MRI、CT影像学征象。比较不同MRI-STIR信号改变患者的CT骨折线类型及CT值。结果经MRI检查,入组患者骨折椎体数共121节,STIR序列呈现黑色线信号45节,无同源高信号36节,同源高信号40节;CT显示,骨折线嵌插型51节,开裂型33节,微骨折型37节。MRI-STIR序列呈现黑色线信号的患者椎体CT骨折线为嵌插型阳性率高于无同源高信号和同源高信号,差异有统计学意义(P<0.05);MRI-STIR序列呈现同源高信号的患者椎体CT骨折线为微骨折型阳性率高于黑色线信号和无同源高信号,差异有统计学意义(P<0.05)。MRI-STIR序列呈现黑色线信号的患者椎体CT值低于无同源高信号和同源高信号,差异有统计学意义(P<0.05)。结论MRI-STIR信号改变与CT骨折线类型存在一定相关性。STIR序列呈现黑色线信号的患者出现椎体嵌插型骨折风险更高,且预后较差。 展开更多
关键词 骨质疏松椎体骨折 磁共振 短反转时间反转恢复序列 电子计算机断层扫描 骨折线类型
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椎基底动脉延长扩张症的基底动脉FLAIR血管高信号征与病症程度和临床症状的相关性
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作者 黄敏 郭潇 +2 位作者 陈伟 王亚婷 柏根基 《中国医学计算机成像杂志》 CSCD 北大核心 2024年第4期405-409,共5页
目的:探讨椎基底动脉延长扩张症(VBD)患者中基底动脉(BA)液体衰减反转恢复(FLAIR)序列血管高信号征(FVH)与病症程度和临床症状的相关性。方法:回顾搜集2018年8月-2023年4月在南京医科大学附属淮安第一医院经头颅MRI及时间飞跃法(TOF)-... 目的:探讨椎基底动脉延长扩张症(VBD)患者中基底动脉(BA)液体衰减反转恢复(FLAIR)序列血管高信号征(FVH)与病症程度和临床症状的相关性。方法:回顾搜集2018年8月-2023年4月在南京医科大学附属淮安第一医院经头颅MRI及时间飞跃法(TOF)-磁共振血管成像(MRA)确诊为VBD患者67例,按照是否出现VBD相关症状(缺血、脑干及神经压迫等)分为症状组(20例)和无症状组(47例),比较2组患者的临床及影像学资料,分析BA的FVH分级与BA病症程度及临床症状的相关性。结果:症状组患者BA管径、FVH发生率显著高于无症状组(P=0.004,P=0.000),症状组中高分级FVH (2、3级)患者比例明显大于无症状组(χ^(2)=11.501,P=0.001)。VBD患者FVH分级与BA的管径、长度及高度分级呈正相关(r=0.563,P=0.000;r=0.482,P=0.000;r=0.512,P=0.000),FVH高级别组(2、3级)BA长度及宽度显著大于低级别组(0、1级)(P=0.000,P=0.000),分叉高度高于低级别组(P=0.012)。结论:VBD患者FVH发生率高,且FVH分级越高,患者出现症状的可能性越大,椎基底动脉病变更严重;FVH形成机制可能与扩张延长的血管中的缓慢血流及不对称扰流有关。 展开更多
关键词 椎基底动脉延长扩张症 基底动脉 液体衰减反转恢复序列 血管高信号征
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心脏延迟增强MRI不同TI值对心肌梗死诊断效能的影响
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作者 陆虹宇 杨映霞 +3 位作者 黄涛 蒋平平 崔盟 林华 《放射学实践》 CSCD 北大核心 2024年第4期473-478,共6页
目的:通过与TI值为300 ms的常规相位敏感反转恢复(PSIR)序列进行比较,探讨调整TI值为左室血池过零时PSIR序列心脏延迟增强MRI对心肌梗死的诊断效能。方法:将2022年3月-2022年12月在本院确诊为心肌梗死的35例患者纳入本研究。所有患者在... 目的:通过与TI值为300 ms的常规相位敏感反转恢复(PSIR)序列进行比较,探讨调整TI值为左室血池过零时PSIR序列心脏延迟增强MRI对心肌梗死的诊断效能。方法:将2022年3月-2022年12月在本院确诊为心肌梗死的35例患者纳入本研究。所有患者在静脉注射Gd-DTPA后10 min分别采用300 ms和血液过零时的TI值行PSIR序列延迟增强(LGE)扫描,扫描平面包括两腔心、四腔心及通过病变区的短轴位。测量并比较2种TI值LGE图像上正常心肌、心肌疤痕与心腔内血液的SNR、CNR和信号强度(SI)的差异及心肌梗死范围的差异。结果:调整TI后LGE图像上心肌疤痕区域与左心室血池的CNR[24.58(16.80,48.51)vs.11.83(5.04,22.73),Z=-6.87,P<0.05]更高,并能显示更大的梗死面积[4.20(2.10,7.55)mm^(2) vs.3.45(1.40,6.15)mm^(2),Z=-6.65,P<0.05],且有更高的疤痕-血池信号强度差[366.80(258.75,432.60)vs.175.90(73.30,259.35),Z=-8.13,P<0.05],更低的正常心肌-血池信号强度差[284.70(196.05,405.20)vs.511.20(394.55,636.70),Z=-8.07,P<0.01]。结论:调整TI后的PSIR序列心脏延迟增强扫描可以有效抑制心腔内血池信号,提高心肌疤痕与血池的对比,而且心内膜下和乳头肌的强化更明显而显示更清晰,从而可提高对梗死区域内心肌活性的检测敏感度。 展开更多
关键词 心肌梗死 相位敏感反转恢复序列 磁共振成像 延迟强化 反转时间
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增强T2 FLAIR序列在颅内肿瘤影像诊断中的研究进展
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作者 梁泓中 郭睿 肖运平 《磁共振成像》 CAS CSCD 北大核心 2024年第4期207-213,共7页
在颅内肿瘤诊疗过程中,对比增强MRI扫描是常用的影像学评估手段。临床上颅脑MRI增强检查首选T1WI序列。长期以来,增强T2液体衰减反转恢复(fluid-attenuated inversion recovery,FLAIR)被认为是评估软脑膜疾病和脑转移瘤的辅助序列。近年... 在颅内肿瘤诊疗过程中,对比增强MRI扫描是常用的影像学评估手段。临床上颅脑MRI增强检查首选T1WI序列。长期以来,增强T2液体衰减反转恢复(fluid-attenuated inversion recovery,FLAIR)被认为是评估软脑膜疾病和脑转移瘤的辅助序列。近年来,不断有研究报道增强T2 FLAIR序列在血脑屏障、血软脑膜屏障、血脑脊液屏障、血眼屏障、血迷路屏障及淋巴系统损伤相关疾病的检出、鉴别诊断方面具有一定优势。增强T2 FLAIR序列尽管在颅内肿瘤影像诊断中展现出巨大的潜力,但目前尚未广泛应用于临床,原因包括:(1)增强T2 FLAIR适用的疾病谱尚未完全阐明,(2)增强T2 FLAIR的规范扫描参数尚未确定,(3)增加MRI检查时间等。本文针对增强T2 FLAIR序列的技术特点、正常影像表现以及在颅内肿瘤影像诊断中的应用现状、最新进展进行综述,为以后进一步科研、临床应用提供参考。 展开更多
关键词 颅内肿瘤 磁共振成像 对比剂 液体衰减反转恢复
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弥散加权成像-T_(2)液体衰减反转恢复序列与弥散加权成像-磁敏感加权成像的图像相符程度及差异程度对急性脑梗死发病时间及预后评估中的价值
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作者 张大为 明艳丽 +2 位作者 张文龙 高忠文 王惠芳 《当代医学》 2024年第5期101-105,共5页
目的探讨急性脑梗死(ACI)患者弥散加权成像(DWI)病变体积(VDWI)、T2液体衰减反转恢复序列(T2Flair)病变体积(VFlair)与发病时间的关系,及ACI患者DWI与磁敏感加权成像(SWI)区域显示一致程度与预后的关系。方法选取2019年8月至2021年12月... 目的探讨急性脑梗死(ACI)患者弥散加权成像(DWI)病变体积(VDWI)、T2液体衰减反转恢复序列(T2Flair)病变体积(VFlair)与发病时间的关系,及ACI患者DWI与磁敏感加权成像(SWI)区域显示一致程度与预后的关系。方法选取2019年8月至2021年12月包钢集团第三职工医院收治的93例ACI患者作为研究对象。运用线性回归分析VFlair、VDWI的体积差与发病时间(T)的关系,分析DWI图像、SWI图像显示区域一致程度与预后的关系。结果线性回归分析结果显示,症状出现6 h内ACI患者VFlair、VDWI与发病时间(T)存在以下关系:(VFlair−VDWI)/VDWI=−0.573+0.103×T;症状出现6~48 h ACI患者VFlair、VDWI与T存在以下关系:(VFlair−VDWI)/VDWI=−0.049+0.013×T。DWI-SWI图像显示区域一致22例,溶栓有效12例(54.55%);DWI-SWI图像显示区域不一致19例,溶栓有效4例(21.05%),两者比较差异有统计学意义(P<0.05)。结论ACI患者VFlair与VDWI差异能有效预测ACI患者发病时间,DWI-SWI区域显示一致程度能够较好预测ACI患者的预后。 展开更多
关键词 脑梗死 体积 液体衰减反转恢复序列 弥散加权成像 磁敏感加权成像
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颅内海绵状血管瘤MRI-SWI T1WI T2FLAIR增强序列检查特征比较观察
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作者 冯天保 许超 陈真 《河北医学》 CAS 2024年第7期1125-1130,共6页
目的:探讨磁共振敏感加权成像(MRI-SWI)、磁共振T1加权成像(T1WI)、T2加权成像(T2WI)、T2液体衰减反转恢复序列(T2FLAIR)在诊断颅内海绵状血管瘤中的应用价值。方法:选取延安大学附属医院2019年3月至2023年3月初步诊断怀疑为颅内海绵状... 目的:探讨磁共振敏感加权成像(MRI-SWI)、磁共振T1加权成像(T1WI)、T2加权成像(T2WI)、T2液体衰减反转恢复序列(T2FLAIR)在诊断颅内海绵状血管瘤中的应用价值。方法:选取延安大学附属医院2019年3月至2023年3月初步诊断怀疑为颅内海绵状血管瘤患者153例作为研究对象,所有患者均在手术前完成了MRI检查,包括MRI-SWI、T1WI、T2WI、T2FLAIR检查,以手术病理学检查结果作为金标准,计算各种MRI检查方式对于诊断颅内海绵状血管瘤的价值。结果:MRI-SWI正确诊断97例海绵状血管瘤患者,共计准确检出病灶数量177个,T1WI正确诊断72例海绵状血管瘤患者,共计准确检出病灶数量121个,T2WI正确诊断77例海绵状血管瘤患者,共计准确检出病灶数量132个,T2FLAIR正确诊断82例海绵状血管瘤患者,共计准确检出病灶数量143个,MRI-SWI对海绵状血管瘤病灶的检出率高于T1WI、T2WI、T2FLAIR(χ^(2)=28.698、P<0.05,χ^(2)=22.299、P<0.05,χ^(2)=16.257、P<0.05);T2FLAIR对海绵状血管瘤病灶的检出率高于T1WI(χ^(2)=7.211、P<0.05);T1WI、T2WI对海绵状血管瘤病灶的检出率差异无统计学意义(χ^(2)=1.676、P>0.05);T2FLAIR、T2WI对海绵状血管瘤病灶的检出率差异无统计学意义(χ^(2)=1.972、P>0.05);T1WI海绵状血管瘤病灶主要表现为混杂信号(43.80%)、其次为低信号(30.58%);T2WI海绵状血管瘤病灶主要表现为混杂信号(49.24%),主要特征为病灶中央呈点状或网格状高信号,周围边缘低信号,称之为“铁环征”,其次为低信号(35.61%);T2FLAIR海绵状血管瘤病灶主要表现为类圆形或者圆形的混杂信号(58.33%),病灶内部显示为爆米花或者网格状,其次为低信号(34.09%);MRI-SWI海绵状血管瘤病灶主要表现为低信号(95.48%),主要显示病灶的周围含铁血黄素区域及瘤体,病灶周边及内部显示片状或点状低信号;T1WI、T2WI、T2FLAIR、MRI-SWI鉴别诊断海绵状血管瘤患者的灵敏度分别为74.23%、79.38%、84.54%、100%,特异度分别为85.71%、83.93%、78.57%、94.64%。结论:颅内海绵状血管瘤患者在接受MRI检查的情况下,MRI-SWI序列较T1WI、T2WI、T2FLAIR序列具有更高的诊断价值。 展开更多
关键词 颅内海绵状血管瘤 磁共振敏感加权成像 磁共振T1加权成像 T2加权成像 T2液体衰减反转恢复序列
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T2-FLAIR影像组学对高级别脑胶质瘤术后1年复发的预测价值 被引量:1
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作者 武敬君 戴慧 +2 位作者 张旼旼 张晴 赵爽爽 《中国医学计算机成像杂志》 CSCD 北大核心 2024年第2期134-140,共7页
目的:探讨T2-液体衰减反转恢复序列(T2-FLAIR)影像组学对高级别脑胶质瘤(HGG)术后1年复发的预测价值。方法:回顾性收集我院2019年1月—2021年12月收治的81例HGG(WHOⅢ~Ⅳ级)患者,所有患者均接受标准的肿瘤切除手术及术后辅助治疗。获取... 目的:探讨T2-液体衰减反转恢复序列(T2-FLAIR)影像组学对高级别脑胶质瘤(HGG)术后1年复发的预测价值。方法:回顾性收集我院2019年1月—2021年12月收治的81例HGG(WHOⅢ~Ⅳ级)患者,所有患者均接受标准的肿瘤切除手术及术后辅助治疗。获取患者术后4周内的MRI T2-FLAIR图像,根据术后1年内的随访数据将患者分为未复发组(51例)和复发组(30例),将所有患者按照7∶3比例随机分配为训练组(57例)和验证组(24例)。采用3D-Slicer软件对残腔周围T2-FLAIR高信号区进行图像分割,并提取851个影像组学特征,包括一阶特征、形状特征、纹理特征、小波变换后的特征。采用观察者一致性检验、最大相关最小冗余算法、最小绝对收缩和选择算子算法逐步进行组学特征选择;采用logistic回归模型构建疗效评估模型;采用受试者工作特征(ROC)曲线分析模型的诊断效能。结果:最终筛选出12个影像组学特征纳入影像组学模型,训练组和验证组ROC曲线下面积(AUC)分别为0.789和0.757。进一步将临床参数IDH1基因突变状态、1p19q杂合缺失情况纳入模型后,联合模型中的AUC在训练组和验证组分别为0.880(95%CI 0.788~0.902)、0.929(95%CI 0.830~1.000),灵敏度分别为0.864、0.857,特异度分别为0.834、0.910。结论:基于T2-FLAIR建立的临床-影像组学联合模型具备早期预测HGG术后1年复发的价值。 展开更多
关键词 高级别脑胶质瘤 T2-液体衰减反转恢复序列 影像组学 复发
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Assessing the Viability of Gandhar Field in India’s Cambay Basin for CO_(2) Storage
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作者 Vikram Vishal Somali Roy +1 位作者 Yashvardhan Verma Bharath Shekar 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第3期529-543,共15页
Our research is centered on the Gandhar oil field, which was discovered in 1983, where daily oil production has declined significantly over the years. The primary objective was to evaluate the feasibility of carbon di... Our research is centered on the Gandhar oil field, which was discovered in 1983, where daily oil production has declined significantly over the years. The primary objective was to evaluate the feasibility of carbon dioxide(CO_(2)) storage through its injection into the siliciclastic reservoirs of Ankleshwar Formation. We aimed to obtain high-resolution acoustic impedance data to estimate porosity employing model-based poststack seismic inversion. We conducted an analysis of the density and effective porosity in the target zone through geostatistical techniques and probabilistic neural networks. Simultaneously, the work also involved geomechanical analysis through the computation of pore pressure and fracture gradient using well-log data, geological information, and drilling events in the Gandhar field. Our investigation unveiled spatial variations in effective porosity within the Hazad Member of the Ankleshwar Formation, with an effective porosity exceeding 25% observed in several areas, which indicates the presence of well-connected pore spaces conducive to efficient CO_(2) migration. Geomechanical analysis showed that the vertical stress(Sv) ranged from 55 MPa to 57 MPa in Telwa and from 63.7 MPa to 67.7 MPa in Hazad Member. The pore pressure profile displayed variations along the stratigraphic sequence, with the shale zone, particularly in the Kanwa Formation, attaining the maximum pressure gradient(approximately 36 MPa). However, consistently low pore pressure values(30-34 MPa) considerably below the fracture gradient curves were observed in Hazad Member due to depletion. The results from our analysis provide valuable insights into shaping future field development strategies and exploration of the feasibility of CO_(2) sequestration in Gandhar Field. 展开更多
关键词 Carbon capture and storage Reservoir characterization Seismic inversion GEOMECHANICS CO_(2)storage CO_(2)enhancing oil recovery
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MRI-DWI在脑梗死缺血半暗带评估及复发的预测价值
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作者 邢海昌 姜顺 刘淑玲 《中国CT和MRI杂志》 2024年第7期4-6,共3页
目的分析磁共振弥散加权成像(MRI-DWI)在脑梗死缺血半暗带评估及复发的预测价值。方法收集我院2020年1月~2022年6月收治的62例急性脑梗死患者临床资料,所有患者均在入院后行MRI检查,并接受静脉溶栓治疗,根据入院时DWI与液体衰减反转恢... 目的分析磁共振弥散加权成像(MRI-DWI)在脑梗死缺血半暗带评估及复发的预测价值。方法收集我院2020年1月~2022年6月收治的62例急性脑梗死患者临床资料,所有患者均在入院后行MRI检查,并接受静脉溶栓治疗,根据入院时DWI与液体衰减反转恢复序列(FLAIR)信号是否一致分为DWI-FLAIR匹配组与DWI-FLAIR不匹配组,比较两组基础疾病、梗死病灶区表观弥散系数(ADC)等基线资料及临床结局,并对所有患者随访1年,观察1年复发率。结果DWI-FLAIR不匹配组病灶体积及溶栓前美国国立卫生研究院卒中量表(NIHSS)评分均显著低于DWI-FLAIR匹配组(P<0.05),ADC值明显高于DWI-FLAIR匹配组(P<0.05)。DWI-FLAIR不匹配组溶栓1d及7d后NIHSS评分显著低于DWIFLAIR匹配组(P<0.05),溶栓30d后预后良好率高于DWI-FLAIR匹配组(P<0.05)。DWI-FLAIR不匹配组1年复发率明显低于DWI-FLAIR匹配组(3.57%vs 26.47%,P<0.05);1年复发患者初次入院时ADC值为(0.29±0.04)×10^(-3)mm^(2)/s,明显低于1年未复发患者入院时的ADC值(0.40±0.08)×10^(-3)mm^(2)/s(P<0.05),ROC曲线也显示,入院时ADC值对预测患者1年复发有统计学意义(P<0.05),其截断值为0.33×10^(-3)mm^(2)/s。结论DWI-FLAIR不匹配提示急性脑梗死患者存在缺血半暗带,静脉溶栓预后较好、复发风险较低,梗死病灶区ADC值也有利于预测患者1年复发风险。 展开更多
关键词 脑梗死 缺血半暗带 磁共振 弥散加权成像 液体衰减反转恢复序列 静脉溶栓 复发
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液体衰减反转恢复序列高信号血管征可预测急性脑梗死患者短期神经功能预后
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作者 乔刚 沈文超 +2 位作者 王欣 王宁 赵京 《内科急危重症杂志》 2024年第2期138-141,150,共5页
目的:探讨液体衰减反转恢复序列(Flair)高信号血管征联合中性粒细胞计数对急性脑梗死(ACI)患者短期神经功能预后的预测价值。方法:选取96例经头颅磁共振确诊的ACI患者,入院时采用美国国立卫生院神经功能缺损评分量表(NIHSS)进行神经功... 目的:探讨液体衰减反转恢复序列(Flair)高信号血管征联合中性粒细胞计数对急性脑梗死(ACI)患者短期神经功能预后的预测价值。方法:选取96例经头颅磁共振确诊的ACI患者,入院时采用美国国立卫生院神经功能缺损评分量表(NIHSS)进行神经功能缺损评分,根据NIHSS评分将其分为轻度组(41例)、中度组(30例)和重度组(25例)。所有患者均进行磁共振检查,对Flair序列上高信号血管征进行评分,分析Flair高信号血管征、中性粒细胞计数与ACI患者短期神经功能预后的关系。患者发病6个月后,采用改变Rankin量表(mRS)评分将其分为预后良好组(81例)和预后不良组(15例)。结果:重度组患者年龄≥60岁、高血压及冠心病史的患者比例、入院时NIHSS评分、病灶直径、中性粒细胞计数均高于中度组和轻度组,而Flair高信号血管征评分低于中度组和轻度组(P均<0.05)。多因素logistic回归分析显示,年龄≥60岁、高血压及冠心病史、入院时NIHSS评分≥12分(OR=1.267,95%CI:1.140~1.409)、中性粒细胞计数升高(OR=1.719,95%CI:1.351~2.188)、Flair高信号血管征评分<4.76分(OR=2.190,95%CI:1.437~3.338)是影响ACI患者神经功能缺损的独立危险因素(P均<0.05)。预后不良组患者Flair高信号血管征评分较低,而中性粒细胞计数较高(P均<0.05)。以预后不良为因变量绘制受试者工作特征(ROC)曲线,结果显示Flair高信号血管征评分截断值为4.76分时,预测ACI患者短期神经功能预后的ROC曲线下面积为0.76(95%CI:0.745~0.826),敏感度和特异度分别为70.33%和64.33%;中性粒细胞计数截断值为5.82×10^(9)/L时,预测ACI患者短期神经功能预后的ROC曲线下面积为0.74(95%CI:0.723~0.814),敏感度和特异度分别为77.56%和63.24%;两者联合预测ACI患者短期神经功能预后的ROC曲线下面积为0.81(95%CI:0.839~0.876),敏感度和特异度分别为80.25%和63.46%。结论:Flair高信号血管征评分降低,中性粒细胞计数升高是影响ACI患者短期神经功能预后的独立危险因素,对评估患者预后具有重要参考价值。 展开更多
关键词 液体衰减反转恢复序列高信号血管征 中性粒细胞计数 急性脑梗死 神经功能 短期预后
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