期刊文献+
共找到94,101篇文章
< 1 2 250 >
每页显示 20 50 100
Hepatocellular carcinoma:Can LI-RADS v2017 with gadoxetic-acid enhancement magnetic resonance and diffusion-weighted imaging improve diagnostic accuracy? 预览
1
作者 Tong Zhang Zi-Xing Huang +8 位作者 Yi Wei Han-Yu Jiang Jie Chen Xi-Jiao Liu Li-Kun Cao Ting Duan Xiao-Peng He Chun-Chao Xia Bin Song 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第5期622-631,共10页
BACKGROUND The Liver Imaging Reporting and Data System(LI-RADS),supported by the American College of Radiology(ACR),has been developed for standardizing the acquisition,interpretation,reporting,and data collection of ... BACKGROUND The Liver Imaging Reporting and Data System(LI-RADS),supported by the American College of Radiology(ACR),has been developed for standardizing the acquisition,interpretation,reporting,and data collection of liver imaging examinations in patients at risk for hepatocellular carcinoma(HCC).Diffusionweighted imaging(DWI),which is described as an ancillary imaging feature of LI-RADS,can improve the diagnostic efficiency of LI-RADS v2017 with gadoxetic acid-enhanced magnetic resonance imaging(MRI)for HCC.AIM To determine whether the use of DWI can improve the diagnostic efficiency of LIRADS v2017 with gadoxetic acid-enhanced magnetic resonance MRI for HCC.METHODS In this institutional review board-approved study,245 observations of high risk of HCC were retrospectively acquired from 203 patients who underwent gadoxetic acid-enhanced MRI from October 2013 to April 2018.Two readers independently measured the maximum diameter and recorded the presence of each lesion and assigned scores according to LI-RADS v2017.The test was used to determine the agreement between the two readers with or without DWI.In addition,the sensitivity(SE),specificity(SP),accuracy(AC),positive predictive value(PPV),and negative predictive value(NPV)of LI-RADS were calculated.Youden index values were used to compare the diagnostic performance of LIRADS with or without DWI.RESULTS Almost perfect interobserver agreement was obtained for the categorization of observations with LI-RADS(kappa value:0.813 without DWI and 0.882 with DWI).For LR-5,the diagnostic SE,SP,and AC values were 61.2%,92.5%,and 71.4%,respectively,with or without DWI;for LR-4/5,they were 73.9%,80%,and 75.9%without DWI and 87.9%,80%,and 85.3%with DWI;for LR-4/5/M,they were 75.8%,58.8%,and 70.2%without DWI and 87.9%,58.8%,and 78.4%with DWI;for LR-4/5/TIV,they were 75.8%,75%,and 75.5%without DWI and 89.7%,75%,and 84.9%with DWI.The Youden index values of the LI-RADS classification without or with DWI were as follows:LR-4/5:0.539 vs 0.679;LR-4/5/M:0.346 vs 0.467;and LR-4/5/TIV: 展开更多
关键词 HEPATOCELLULAR carcinoma Liver IMAGING REPORTING and Data System Magnetic RESONANCE IMAGING DIFFUSION-WEIGHTED IMAGING Diagnosis
在线阅读 免费下载
Evaluation of tumor response to antiangiogenic therapy in patients with recurrent gliomas using contrast-enhanced perfusion-weighted magnetic resonance imaging techniques: A meta-analysis 预览
2
作者 Akanganyira Kasenene Aju Baidya +1 位作者 Salman Shams Hai-Bo Xu 《世界荟萃分析杂志》 2019年第2期51-65,共15页
BACKGROUND It is of vital importance to find radiologic biomarkers that can accurately predict treatment response. Usually, the initiation of antiangiogenic therapy causes a rapid decrease in the contrast enhancing tu... BACKGROUND It is of vital importance to find radiologic biomarkers that can accurately predict treatment response. Usually, the initiation of antiangiogenic therapy causes a rapid decrease in the contrast enhancing tumor. However, the treatment response is observed only in a fraction of patients due to the partial radiological response secondary to stabilization of abnormal vessels which does not essentially indicate a true antitumor effect. Perfusion-weighted magnetic resonance imaging (PWMRI) techniques have shown implicitness as a strong imaging biomarker for gliomas since they give hemodynamic information of blood vessels. Hence, there is a rapid expansion of PW-MRI related studies and clinical applications. AIM To determine the diagnostic performance of PW-MRI techniques including:(A) dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI);and (B) dynamic susceptibility contrast magnetic resonance imaging (DSC-MRI) for evaluating response to antiangiogenic therapy in patients with recurrent gliomas. METHODS Databases such as PubMed (MEDLINE included), EMBASE, and Google Scholar were searched for relevant original articles. The included studies were assessed for methodological quality with the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Medical imaging follow-up or histopathological analysis was used as the reference standard. The data were extracted by two reviewers independently, and then the sensitivity, specificity, summary receiver operating characteristic curve, area under the curve (AUC), and heterogeneity were calculated using Meta-Disc 1.4 software.RESULTS This study analyzed a total of six articles. The overall sensitivity for DCE-MRI and DSC-MRI was 0.69 [95% confidence interval (CI): 0.53-0.82], and the specificity was 0.99 (95%CI: 0.93-1) by a random effects model (DerSimonianee- Laird model). The likelihood ratio (LR)+, LR-, and diagnostic odds ratio (DOR) were 12.84 (4.54-36.28), 0.35 (0.22-0.53), and 24.44 (7.19-83.06), respectively. The AUC (± SE) was 0.9921 (± 0.0120), 展开更多
关键词 Glioma Perfusion-weighted MAGNETIC RESONANCE IMAGING DYNAMIC contrastenhanced MAGNETIC RESONANCE IMAGING DYNAMIC susceptibility contrast MAGNETIC RESONANCE IMAGING Anti-vascular endothelial growth factor ANTIANGIOGENIC Metaanalysis
在线阅读 免费下载
Cardiac involvement in disseminated diffuse large B-cell lymphoma,successful management with chemotherapy dose reduction guided by cardiac imaging:A case report and review of literature 预览
3
作者 Rabah Al-Mehisen Maha Al-Mohaissen Hisham Yousef 《世界临床病例杂志》 2019年第2期191-202,共12页
BACKGROUND Secondary cardiac involvement by lymphoma has received limited attention in the medical literature,despite its grave prognosis.Although chemotherapy improves patients’survival,a subgroup of treated patient... BACKGROUND Secondary cardiac involvement by lymphoma has received limited attention in the medical literature,despite its grave prognosis.Although chemotherapy improves patients’survival,a subgroup of treated patients dies suddenly due to myocardial rupture following chemotherapy initiation.Reducing the initial chemotherapy dose with dose escalation to standard doses may be effective in minimizing this risk but the data are limited.We report on the successful management of a patient with disseminated diffuse large B-cell lymphoma(DLBCL)involving the heart using such approach.CASE SUMMARY An 18-year-old male presented to our hospital with six months history of progressive dyspnea,orthopnea and cough.On physical examination,the patient was found to have a plethoric and mildly edematous face,fixed elevation of the right internal jugular vein,suggestive of superior vena cava obstruction,and a pelvic mass.Investigations during admission including a thoracoabdominal computed tomography(CT)scan with CT guided biopsy of the pelvic mass,echocardiography and cardiac magnetic resonance imaging led to the diagnosis of disseminated DLBCL with cardiac involvement.The patients were successfully treated with chemotherapy dose reduction followed by dose escalation to standard doses,under the guidance of cardiac imaging.The patient completed chemotherapy and underwent a successful bone marrow transplant.He is currently in remission and has a normal left ventricular function.CONCLUSION Imaging-guided chemotherapy dosing may minimize the risk of myocardial rupture in cardiac lymphoma.Data are limited.Management should be individualized. 展开更多
关键词 Diffuse large B-cell LYMPHOMA CARDIAC LYMPHOMA CARDIAC IMAGING CARDIAC magnetic resonance IMAGING Myocardial rupture Imaging-guided CHEMOTHERAPY Case report
在线阅读 免费下载
Color-coded perfluorocarbon nanodroplets for multiplexed ultrasound and photoacoustic imaging
4
作者 Daniela Y. Santiesteban Kristina A. Hallam +1 位作者 Steven K. Yarmoska Stanislav Y. Emelianov 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第4期741-747,共7页
Laser-activated perfluorocarb on n anodroplets are an emerging class of phase-cha nge, dual-c ontrast age nts that can be utilized in ultraso und and photoacoustic imaging. Through the ability to differe ntiate subpop... Laser-activated perfluorocarb on n anodroplets are an emerging class of phase-cha nge, dual-c ontrast age nts that can be utilized in ultraso und and photoacoustic imaging. Through the ability to differe ntiate subpopulations of nano droplets via laser activatio n at differe nt wavelengths of n ear-infrared light, optically-triggered color-coded perfluorocarb on nano droplets prese nt themselves as an attractive tool for multiplexed ultrasound and photoacoustic imaging. In particular, laser-activated droplets can be used to provide quantitative spatiotemporal information regarding distinct biological targets, allowing for their potential use in a wide range of diagnostic and therapeutic applications. In the work prese nted, laser-activated color-coded perfluorocarb on nan odroplets are syn thesized to selectively resp ond to laser irradiati on at corresp on ding wavele ngths. The dyn amic ultraso und and photoacoustic signals produced by laser-activated perfluorocarbon nano droplets are evaluated in situ prior to implementation in a murine model. In vivo, these particles are used to distinguish unique particle trafficking mechanisms and are show n to provide ultraso und and photoacoustic contrast for up to 72 hours within lymphatics. Overall, the con ducted studies show that laser-activated color-coded perfluorocarbo n nano droplets are a promising agent for multiplexed ultraso und and photoacoustic imaging. 展开更多
关键词 multiplexed IMAGING PERFLUOROCARBON NANODROPLETS PHOTOACOUSTIC IMAGING ULTRASOUND IMAGING molecular targets
前列腺癌正电子显像剂的临床研究及应用进展 预览
5
作者 张宝平 孙洪赞 郭启勇 《现代肿瘤医学》 CAS 2019年第11期2013-2018,共6页
PET/CT及PET/MR近年来已被应用于前列腺癌的临床检测。通过应用不同的显像剂,PET/CT及PET/MR可以评估前列腺癌的糖代谢、脂质代谢、受体变化等生物学改变,在前列腺癌的诊断、指导治疗及预后评估等方面相对于常规检测手段有独特的优势和... PET/CT及PET/MR近年来已被应用于前列腺癌的临床检测。通过应用不同的显像剂,PET/CT及PET/MR可以评估前列腺癌的糖代谢、脂质代谢、受体变化等生物学改变,在前列腺癌的诊断、指导治疗及预后评估等方面相对于常规检测手段有独特的优势和良好的效果。近年来,许多新的放射性标记物不断被引入临床,给前列腺癌的诊断及治疗带来更广阔的应用前景。本文主要对前列腺癌正电子显像剂的临床研究及应用进展进行综述。 展开更多
关键词 PET/MR PET 前列腺癌 影像学 显像剂
在线阅读 下载PDF
A high-performance bio-tissue imaging method using air flow-assisted desorption electrospray ionization coupled with a high-resolution mass spectrometer
6
作者 Yiwei Lv Tiegang Li +9 位作者 Chengan Guo Chenglong Sun Fei Tang Luojiao Huang Zhigang Luo Xin Li Ruiping Zhang Qingce Zang Jiuming He Zeper AbliZ 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期461-464,共4页
Mass spectrometry imaging (MSI) technology can simultaneously obtain the spatial distribution of thousands of chemical compounds and has unique advantages compared to other techniques that allow mapping the surface of... Mass spectrometry imaging (MSI) technology can simultaneously obtain the spatial distribution of thousands of chemical compounds and has unique advantages compared to other techniques that allow mapping the surface of bio-tissue. Here, we combined an air flow-assisted desorption electrospray ionization (AFADESI) MSI device with a high-resolution mass spectrometer to optimize the system parameters and achieve more accurate spatial distribution characteristics for compounds of interest while investigating bio-tissue sections. The platform set-up, required instrumentation, sample pretreatment, parameter optimization and bio-tissue characterization are described and discussed.Finally, the parameter conditions that can provide optimal ionic intensity and enhanced resolution were confirmed. The reasonable resolution and sensitivity improvements of AFADESI-MSI have been achieved through tandem a high-resolution mass spectrometer system, therefore, it would be a promising technique for the bio-tissue imaging analysis. 展开更多
关键词 Mass SPECTROMETRY IMAGING Air flow-assisted desorption electrospray ionization HIGH-RESOLUTION mass SPECTROMETRY Endogenous metabolites Bio-tissue IMAGING
三维可视化技术联合术中ICG荧光显像在腹腔镜肝癌肝切除术中的应用 预览
7
作者 李锟 张中林 +5 位作者 刘权焰 常磊 李震 潘定宇 刘志苏 袁玉峰 《中华肝脏外科手术学电子杂志》 CAS 2019年第3期226-229,共4页
目的探讨三维可视化技术联合术中ICG 荧光显像在腹腔镜原发性肝癌(肝癌)肝切除术中的应用价值。方法回顾性分析2017 年6 月至2018 年6 月武汉大学中南医院联合应用三维可视化技术和术中ICG 荧光显像技术行腹腔镜肝切除术的51 例肝癌患... 目的探讨三维可视化技术联合术中ICG 荧光显像在腹腔镜原发性肝癌(肝癌)肝切除术中的应用价值。方法回顾性分析2017 年6 月至2018 年6 月武汉大学中南医院联合应用三维可视化技术和术中ICG 荧光显像技术行腹腔镜肝切除术的51 例肝癌患者临床资料。其中男24 例,女27 例;平均年龄(57±15)岁。患者均签署知情同意书,符合医学伦理学规定。术前应用三维可视化技术进行肝脏三维重建,明确肝内脉管系统的解剖关系及其与肿瘤的毗邻关系。术中ICG 荧光显像技术和彩色多普勒超声确定肝切除线,行精准肝切除。观察手术时间、术中出血量、并发症发生率、围手术期死亡率等。结果 51 例患者均成功实施腹腔镜肝切除术,无术中中转开腹病例。手术时间为(260±150)min,术中出血量(196±104)ml,术后住院时间(9±3)d。无发生术后肝衰竭和围手术期死亡。术后发生并发症5 例,均为Clavien-Dindo Ⅱ级,经保守治疗后治愈出院。随访期间4 例患者出现肝癌复发或转移。结论三维可视化技术联合ICG 荧光显像技术能清晰显示肝癌与肝脏脉管结构的关系,并能准确预测肝癌肝切除范围,提高腹腔镜肝切除术的安全性。 展开更多
关键词 腹腔镜 肝切除术 肝细胞 成像 三维 吲哚氰绿 荧光显像
在线阅读 下载PDF
NIR-II fluorescence in vivo confocal microscopy with aggregation-induced emission dots
8
作者 Wenbin Yu Bing Guo +7 位作者 Hequn Zhang Jing Zhou Xiaoming Yu Liang Zhu Dingwei Xue Wen Liu Xianhe Sun Jun Qian 《科学通报:英文版》 SCIE EI CSCD 2019年第6期410-416,共7页
Significantly reduced tissue scattering of fluorescence signals in the second near-infrared(NIR-Ⅱ,1,000–1,700 nm)spectral region offers opportunities for large-depth in vivo bioimaging.Nowadays,most reported works c... Significantly reduced tissue scattering of fluorescence signals in the second near-infrared(NIR-Ⅱ,1,000–1,700 nm)spectral region offers opportunities for large-depth in vivo bioimaging.Nowadays,most reported works concerning NIR-II fluorescence in vivo bioimaging are realized by wide-field illumination and 2D-arrayed detection(e.g.,via InGaAs camera),which has high temporal resolution but limited spatial resolution due to out-of-focus signals.Combining NIR-II fluorescence imaging with confocal microscopy is a good approach to achieve high-spatial resolution visualization of biosamples even at deep tissues.In this presented work,a NIR-II fluorescence confocal microscopic system was setup.By using a kind of aggregation-induced emission(AIE)dots as NIR-II fluorescent probes,800 lm-deep 3D in vivo cerebrovascular imaging of a mouse was obtained,and the spatial resolution at 700 lm depth could reach 8.78 lm.Moreover,the time-correlated single photon counting(TCSPC)technique and femtosecond laser excitation were introduced into NIR-II fluorescence confocal microscopy,and in vivo confocal NIR-II fluorescence lifetime microscopic imaging(FLIM)of mouse cerebral vasculature was successfully realized. 展开更多
关键词 Confocal microscopy NIR-II FLUORESCENCE AIE DOTS In vivo cerebrovascular IMAGING TCSPC FLIM IMAGING
Imaging method of single layer graphene on metal substrate based on imaging ellipsometer with large field of view
9
作者 李桂运 谷利元 +3 位作者 胡敬佩 朱玲琳 曾爱军 黄惠杰 《中国光学快报:英文版》 SCIE EI CAS CSCD 2019年第1期40-42,共3页
Single layer lattice graphene deposited on the metal substrate can hardly be imaged by the optical microscope. In this Letter, a large field-of-view imaging ellipsometer is introduced to image single layer graphene wh... Single layer lattice graphene deposited on the metal substrate can hardly be imaged by the optical microscope. In this Letter, a large field-of-view imaging ellipsometer is introduced to image single layer graphene which is deposited on a metal substrate. By adjusting the polarizer and the analyzer of imaging ellipsometer, the light reflected from surfaces of either single layer graphene or a Au film substrate can be extinguished, respectively.Thus, single layer graphene can be imaged correspondingly under brightfield or darkfield imaging modes. The method can be applied to imaging large-area graphene on a metal substrate. 展开更多
关键词 IMAGING method SINGLE LAYER GRAPHENE IMAGING ellipsometer LARGE FIELD
全文增补中
Imaging Beyond the Angiogram in Women with Suspected Myocardial Infarction and No Obstructive Coronary Artery Disease 预览
10
作者 Sohah N.Iqbal,MD,FACC,FSCAI 《心血管创新与应用》 2019年第B04期25-30,共6页
A subset of women referred to the cardiac catheterization lab for suspected myocardial infarction thought to be due to a culprit artery are found to have no obstructive coronary artery disease by angiography.The mecha... A subset of women referred to the cardiac catheterization lab for suspected myocardial infarction thought to be due to a culprit artery are found to have no obstructive coronary artery disease by angiography.The mechanism by which these women have myocardial injury varies and is not usually clear by history and angiography alone.Additional imaging,including modalities such as cardiac MRI,intravascular imaging,and computed tomography may be helpful to clarify diagnoses and direct treatment. 展开更多
关键词 WOMEN myocardial infarction IMAGING ANGIOGRAM INTRACORONARY IMAGING cardiac MRI
在线阅读 免费下载
Influence exerted by bone-containing target body on thermoacoustic imaging with current injection
11
作者 李艳红 刘国强 +1 位作者 宋佳祥 夏慧 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第4期230-241,共12页
Thermoacoustic imaging with current injection(TAI-CI) is a novel imaging technology that couples with electromagnetic and acoustic research, which combines the advantages of high contrast of the electrical impedance t... Thermoacoustic imaging with current injection(TAI-CI) is a novel imaging technology that couples with electromagnetic and acoustic research, which combines the advantages of high contrast of the electrical impedance tomography and the high spatial resolution of sonography, and therefore has the potential for early diagnosis. To verify the feasibility of TAI-CI for complex bone-containing biological tissues, the principle of TAI-CI and the coupling characteristics of fluid and solid were analyzed. Meanwhile, thermoacoustic(TA) effects for fluid model and fluid–solid coupling model were analyzed by numerical simulations. Moreover, we conducted experiments on animal cartilage, hard bone and biological soft tissue phantom with low conductivity(0.5 S/m). By injecting a current into the phantom, the thermoacoustic signal was detected by the ultrasonic transducer with a center frequency of 1 MHz, thereby the B-scan image of the objects was obtained. The B-scan image of the cartilage experiment accurately reflects the distribution of cartilage and gel, and the hard bone has a certain attenuation effect on the acoustic signal. However, compared with the ultrasonic imaging, the thermoacoustic signal is only attenuated during the outward propagation. Even in this case, a clear image can still be obtained and the images can reflect the change of the conductivity of the gel. This study confirmed the feasibility of TAI-CI for the imaging of biological tissue under the presence of cartilage and the bone. The novel TAI-CI method provides further evidence that it can be used in the diagnosis of human diseases. 展开更多
关键词 BIOMEDICAL IMAGING thermo-acoustic IMAGING fluid–solid coupling low conductivity
Quest for the best endoscopic imaging modality for computer-assisted colonic polyp staging 预览
12
作者 Georg Wimmer Michael Gadermayr +8 位作者 Gernot Wolkersd?rfer Roland Kwitt Toru Tamaki Jens Tischendorf Michael H?fner Shigeto Yoshida Shinji Tanaka Dorit Merhof Andreas Uh 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第10期1197-1209,共13页
BACKGROUND It was shown in previous studies that high definition endoscopy, high magnification endoscopy and image enhancement technologies, such as chromoendoscopy and digital chromoendoscopy [narrow-band imaging(NBI... BACKGROUND It was shown in previous studies that high definition endoscopy, high magnification endoscopy and image enhancement technologies, such as chromoendoscopy and digital chromoendoscopy [narrow-band imaging(NBI), iScan] facilitate the detection and classification of colonic polyps during endoscopic sessions. However, there are no comprehensive studies so far that analyze which endoscopic imaging modalities facilitate the automated classification of colonic polyps. In this work, we investigate the impact of endoscopic imaging modalities on the results of computer-assisted diagnosis systems for colonic polyp staging.AIM To assess which endoscopic imaging modalities are best suited for the computerassisted staging of colonic polyps.METHODS In our experiments, we apply twelve state-of-the-art feature extraction methods for the classification of colonic polyps to five endoscopic image databases of colonic lesions. For this purpose, we employ a specifically designed experimental setup to avoid biases in the outcomes caused by differing numbers of images per image database. The image databases were obtained using different imaging modalities. Two databases were obtained by high-definition endoscopy in combination with i-Scan technology(one with chromoendoscopy and one without chromoendoscopy). Three databases were obtained by highmagnification endoscopy(two databases using narrow band imaging and one using chromoendoscopy). The lesions are categorized into non-neoplastic and neoplastic according to the histological diagnosis.RESULTS Generally, it is feature-dependent which imaging modalities achieve high results and which do not. For the high-definition image databases, we achieved overall classification rates of up to 79.2% with chromoendoscopy and 88.9% without chromoendoscopy. In the case of the database obtained by high-magnification chromoendoscopy, the classification rates were up to 81.4%. For the combination of high-magnification endoscopy with NBI, results of up to 97.4% for one database and up to 84% fo 展开更多
关键词 Endoscopy Colonic POLYPS Automated diagnosis system NARROW-BAND IMAGING CHROMOENDOSCOPY IMAGING MODALITIES Image enhancement technologies
在线阅读 免费下载
Evolving screening and surveillance techniques for Barrett's esophagus 预览
13
作者 David Steele Kondal Kyanam Kabir Baig Shajan Peter 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第17期2045-2057,共13页
Barrett’s esophagus (BE) is a change in the esophageal lining and is known to be the major precursor lesion for most cases of esophageal adenocarcinoma (EAC). Despite an understanding of its association with BE for m... Barrett’s esophagus (BE) is a change in the esophageal lining and is known to be the major precursor lesion for most cases of esophageal adenocarcinoma (EAC). Despite an understanding of its association with BE for many years and the falling incidence rates of squamous cell carcinoma of the esophagus, the incidence for EAC continues to rise exponentially. In association with this rising incidence, if the delay in diagnosis of EAC occurs after the onset of symptoms, then the mortality at 5 years is greater than 80%. Appropriate diagnosis and surveillance strategies are therefore vital for BE. Multiple novel optical technologies and other advanced approaches are being utilized to assist in making screening and surveillance more cost effective. We review the current guidelines and evolving techniques that are currently being evaluated. 展开更多
关键词 Barrett’s ESOPHAGUS SCREENING SURVEILLANCE New TECHNIQUES Endoscopy IMAGING Radiofrequency ablation Narrow band IMAGING
在线阅读 免费下载
Diffusion kurtosis imaging of microstructural changes in brain tissue affected by acute ischemic stroke in different locations 预览
14
作者 Liu-Hong Zhu Zhong-Ping Zhang +2 位作者 Fu-Nan Wang Qi-Hua Cheng Gang Guo 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第2期272-279,共8页
The location of an acute ischemic stroke is associated with its prognosis. The widely used Gaussian model-based parameter, apparent diffusion coefficient (ADC), cannot reveal microstructural changes in different locat... The location of an acute ischemic stroke is associated with its prognosis. The widely used Gaussian model-based parameter, apparent diffusion coefficient (ADC), cannot reveal microstructural changes in different locations or the degree of infarction. This prospective observational study was reviewed and approved by the Institutional Review Board of Xiamen Second Hospital, China (approval No. 2014002). Diffusion kurtosis imaging (DKI) was used to detect 199 lesions in 156 patients with acute ischemic stroke (61 males and 95 females), mean age 63.15 ± 12.34 years. A total of 199 lesions were located in the periventricular white matter (n = 52), corpus callosum (n = 14), cerebellum (n = 29), basal ganglia and thalamus (n = 21), brainstem (n = 21) and gray-white matter junctions (n = 62). Percentage changes of apparent diffusion coefficient (ΔADC) and DKI-derived indices (fractional anisotropy [ΔFA], mean diffusivity [ΔMD], axial diffusivity [ΔDa], radial diffusivity ΔDr, mean kurtosis [ΔMK], axial kurtosis [ΔKa], and radial kurtosis [ΔKr]) of each lesion were computed relative to the normal contralateral region. The results showed that (1) there was no significant difference in ΔADC, ΔMD, ΔDa or ΔDr among almost all locations. (2) There was significant difference in ΔMK among almost all locations (except basal ganglia and thalamus vs. brain stem; basal ganglia and thalamus vs. gray-white matter junctions; and brainstem vs. gray-white matter junctions. (3) The degree of change in diffusional kurtosis in descending order was as follows: corpus callosum > periventricular white matter > brainstem > gray-white matter junctions > basal ganglia and thalamus > cerebellum. In conclusion, DKI could reveal the differences in microstructure changes among various locations affected by acute ischemic stroke, and performed better than diffusivity among all groups. 展开更多
关键词 nerve REGENERATION apparent DIFFUSION coefficient DIFFUSION weighted IMAGING DIFFUSION KURTOSIS IMAGING acute ISCHEMIC stroke mean KURTOSIS microstructure changes white matter 1.5 TESLA magnetic resonance system neural REGENERATION
在线阅读 下载PDF
The applied research of simultaneous image acquisition of T2-weighted imaging(T2WI)and diffusion-weighted imaging(DWI)in the assessment of patients with prostate cancer
15
作者 Yi Liu Wei Wang +4 位作者 Xiu-Bo Qin Hui-Hui Wang Ge Gao Xiao-Dong Zhang Xiao-Ying Wang 《亚洲男性学杂志:英文版》 SCIE CAS CSCD 2019年第2期177-182,共6页
We aimed to evaluate the feasibility of simultaneous image acquisition of multiple instantaneous switchable scan(MISS)for prostate magnetic resonance imaging(MRI)on 3T.Fifty-three patients were scanned with MRI due to... We aimed to evaluate the feasibility of simultaneous image acquisition of multiple instantaneous switchable scan(MISS)for prostate magnetic resonance imaging(MRI)on 3T.Fifty-three patients were scanned with MRI due to suspected prostate cancer.Twenty-eight of them got histological results.First,two readers assessed the structure delineation and image quality based on images of conventional T2-weighted imaging(T2WI)and diffusion-weighted imaging(DWI)(CTD).Second,two readers identified the index lesion together,and then,reader one evaluated the contrast of index lesion on T2WI and signal ratio on apparent diffusion coefficient map.Third,they assigned Prostate Imaging Reporting and Data System(PI-RADS)score in consensus for the index lesion.After 4 weeks,the images of MISS were reviewed by the same readers following the same process.Finally,two readers gave preference for image interpretation,respectively.Kappa coefficient,Wilcoxon signed-rank test,paired-sample t-test,Bland-Altman analysis,and receiver operating characteristic(ROC)analysis were used for statistical analysis.The acquisition time of CTD was 6 min and 10 st while the acquisition time of MISS was 4 min and 30 s.Interobserver agreements for image evaluation were k=0.65 and k=0.80 for CTD and MISS,respectively.MISS-T2WI showed better delineation for seminal vesicles than CTD-T2WI(reader 1:P<0.001,reader 2:P=0.001).The index lesion demonstrated higher contrast in MISS-T2WI(P<0.001).The FI-RADS scores based on CTD and MISS exhibited high ability in predicting clinically significant cancer(area under curve[AUC]=0.828 vs 0.854).Readers preferred to use MISS in 41.5%-47.2%of cases.MISS showed comparable performance to conventional technique with less acquisition time. 展开更多
关键词 DIFFUSION-WEIGHTED IMAGING magnetic resonance IMAGING PROSTATE cancer
Evolving role of magnetic resonance techniques in primary sclerosing cholangitis 预览
16
作者 Emmanuel A Selvaraj Emma L Culver +3 位作者 Helen Bungay Adam Bailey Roger W Chapman Michael Pavlides 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第6期644-658,共15页
Development of non-invasive methods to risk-stratify patients and predict clinical endpoints have been identified as one of the key research priorities in primary sclerosing cholangitis(PSC).In addition to serum and h... Development of non-invasive methods to risk-stratify patients and predict clinical endpoints have been identified as one of the key research priorities in primary sclerosing cholangitis(PSC).In addition to serum and histological biomarkers,there has been much recent interest in developing imaging biomarkers that can predict disease course and clinical outcomes in PSC.Magnetic resonance imaging/magnetic resonance cholangiopancreatography(MRI/MRCP)continue to play a central role in the diagnosis and follow-up of PSC patients.Magnetic resonance(MR)techniques have undergone significant advancement over the last three decades both in MR data acquisition and interpretation.The progression from a qualitative to quantitative approach in MR acquisition techniques and data interpretation,offers the opportunity for the development of objective and reproducible imaging biomarkers that can potentially be incorporated as an additional endpoint in clinical trials.This review article will discuss how the role of MR techniques have evolved over the last three decades from emerging as an alternative diagnostic tool to endoscopic retrograde cholangiopancreatography,to being instrumental in the ongoing search for imaging biomarker of disease stage,progression and prognosis in PSC. 展开更多
关键词 Primary SCLEROSING cholangitis MAGNETIC RESONANCE IMAGING MAGNETIC RESONANCE CHOLANGIOPANCREATOGRAPHY MAGNETIC RESONANCE ELASTOGRAPHY Diffusion MAGNETIC RESONANCE IMAGING Endoscopic retrograde CHOLANGIOPANCREATOGRAPHY
在线阅读 免费下载
Influence of random phase modulation on the imaging quality of computational ghost imaging
17
作者 高超 王晓茜 +3 位作者 蔡宏吉 任捷 刘籍元 姚治海 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第2期77-81,共5页
In this paper, we investigated phase modulation-based computational ghost imaging. According to the results of numerical simulations, we found that the range of the random phase affects the quality of the reconstructe... In this paper, we investigated phase modulation-based computational ghost imaging. According to the results of numerical simulations, we found that the range of the random phase affects the quality of the reconstructed image. Besides,compared with those amplitude modulation-based computational ghost imaging schemes, introducing random phase modulation into the computational ghost imaging scheme could significantly improve the spatial resolution of the reconstructed image, and also extend the field of view. 展开更多
关键词 COMPUTATIONAL GHOST IMAGING RANDOM PHASE MODULATION IMAGING quality
Microstructural damage pattern of vascular cognitive impairment:a comparison between moyamoya disease and cerebrovascular atherosclerotic disease 预览
18
作者 Jia-Bin Su Si-Da Xi +7 位作者 Shu-Yi Zhou Xin Zhang Shen-Hong Jiang Bin Xu Liang Chen Yu Lei Chao Gao Yu-Xiang Gu 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第5期858-867,共10页
Moyamoya disease and cerebrovascular atherosclerotic disease are both chronic ischemic diseases with similar presentations of vascular cognitive impairment.The aim of the present study was to investigate the patterns ... Moyamoya disease and cerebrovascular atherosclerotic disease are both chronic ischemic diseases with similar presentations of vascular cognitive impairment.The aim of the present study was to investigate the patterns of microstructural damage associated with vascular cognitive impairment in the two diseases.The study recruited 34 patients with moyamoya disease(age 43.9±9.2 years;20 men and 14 women,27 patients with cerebrovascular atherosclerotic disease(age:44.6±7.6 years;17 men and 10 women),and 31 normal controls(age 43.6±7.3 years;18 men and 13 women)from Huashan Hospital of Fudan University in China.Cognitive function was assessed using the Mini-Mental State Examination,long-term delayed recall of Auditory Verbal Learning Test,Trail Making Test Part B,and the Symbol Digit Modalities Test.Single-photon emission-computed tomography was used to examine cerebral perfusion.Voxel-based morphometry and tract-based spatial statistics were performed to identify regions of gray matter atrophy and white matter deterioration in patients and normal controls.The results demonstrated that the severity of cognitive impairment was similar between the two diseases in all tested domains.Patients with moyamoya disease and those with cerebrovascular atherosclerotic disease suffered from disturbed supratentorial hemodynamics.Gray matter atrophy in bilateral middle cingulate cortex and parts of the frontal gyrus was prominent in both diseases,but in general,was more severe and more diffuse in those with moyamoya disease.White matter deterioration was significant for both diseases in the genu and body of corpus callosum,in the anterior and superior corona radiation,and in the posterior thalamic radiation,but in moyamoya disease,it was more diffuse and more severe.Vascular cognitive impairment was associated with regional microstructural damage,with a potential link between,gray and white matter damage.Overall,these results provide insight into the pathophysiological nature of vascular cognitive impairment.This study was approved 展开更多
关键词 nerve REGENERATION vascular cognitive impairment MOYAMOYA DISEASE CEREBROVASCULAR atherosclerotic DISEASE magnetic resonance IMAGING diffusion tensor IMAGING gray matter volume tract-based spatial statistics SINGLE-PHOTON emission computed tomography neural REGENERATION
在线阅读 下载PDF
Artificial intelligence system of faster region-based convolutional neural network surpassing senior radiologists in evaluation of metastatic lymph nodes of rectal cancer
19
作者 Lei Ding Guang-Wei Liu +11 位作者 Bao-Chun Zhao Yun-Peng Zhou Shuai Li Zheng-Dong Zhang Yu-Ting Guo Ai-Qin Li Yun Lu Hong-Wei Yao Wei-Tang Yuan Gui-Ying Wang Dian-Liang Zhang Lei Wang 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第4期379-387,共9页
Background: An artificial intelligence system of Faster Region-based Convolutional Neural Network (Faster R-CNN) is newly developed for the diagnosis of metastatic lymph node (LN) in rectal cancer patients. The primar... Background: An artificial intelligence system of Faster Region-based Convolutional Neural Network (Faster R-CNN) is newly developed for the diagnosis of metastatic lymph node (LN) in rectal cancer patients. The primary objective of this study was to comprehensively verify its accuracy in clinical use. Methods: Four hundred fourteen patients with rectal cancer discharged between January 2013 and March 2015 were collected from 6 clinical centers, and the magnetic resonance imaging data for pelvic metastatic LNs of each patient was identified by Faster R-CNN. Faster R-CNN based diagnoses were compared with radiologist based diagnoses and pathologist based diagnoses for methodological verification, using correlation analyses and consistency check. For clinical verification, the patients were retrospectively followed up by telephone for 36 months, with post-operative recurrence of rectal cancer as a clinical outcome;recurrence-free survivals of the patients were compared among different diagnostic groups, by methods of Kaplan-Meier and Cox hazards regression model. Results: Significant correlations were observed between any 2 factors among the numbers of metastatic LNs separately diagnosed by radiologists, Faster R-CNN and pathologists, as evidenced by rradiologist-Faster R-CNN of 0.912, rPathologist-radiologist of 0.134, and rPathologist-Faster R-CNN of 0.448 respectively. The value of kappa coefficient in N staging between Faster R-CNN and pathologists was 0.573, and this value between radiologists and pathologists was 0.473. The 3 groups of Faster R-CNN, radiologists and pathologists showed no significant differences in the recurrence-free survival time for stage N0 and N1 patients, but significant differences were found for stage N2 patients. Conclusion: Faster R-CNN surpasses radiologists in the evaluation of pelvic metastatic LNs of rectal cancer, but is not on par with pathologists. 展开更多
关键词 AI (Artificial Intelligence) Magnetic resonance imaging PATHOLOGY LYMPH NODES RECTAL cancer
Parallel implementation of w-projection wide-?eld imaging
20
作者 Baoqiang Lao Tao An +5 位作者 Ang Yu Wenhui Zhang Junyi Wang Quan Guo Shaoguang Guo Xiaocong Wu 《科学通报:英文版》 SCIE EI CSCD 2019年第9期586-594,共9页
w-Projection is a wide-field imaging technique that is widely used in radio synthesis arrays. Processing the wide-field big data generated by the future Square Kilometre Array(SKA) will require significant updates to ... w-Projection is a wide-field imaging technique that is widely used in radio synthesis arrays. Processing the wide-field big data generated by the future Square Kilometre Array(SKA) will require significant updates to current methods to significantly reduce the time consumed on data processing. Data loading and gridding are found to be two major time-consuming tasks in w-projection. In this paper, we investigate two parallel methods of accelerating w-projection processing on multiple nodes: the hybrid Message Passing Interface(MPI) and Open Multi-Processing(OpenMP) method based on multicore Central Processing Units(CPUs) and the hybrid MPI and Compute Unified Device Architecture(CUDA)method based on Graphics Processing Units(GPUs). Both methods are successfully employed and operated in various computational environments, confirming their robustness. The experimental results show that the total runtime of both MPI + OpenMP and MPI + CUDA methods is significantly shorter than that of single-thread processing. MPI + CUDA generally shows faster performance when running on multiple nodes than MPI + OpenMP, especially on large numbers of nodes. The single-precision GPU-based processing yields faster computation than the double-precision processing;while the single-and doubleprecision CPU-based processing shows consistent computational performance. The gridding time remarkably increases when the support size of the convolution kernel is larger than 8 and the image size is larger than 2,048 pixels. The present research offers useful guidance for developing SKA imaging pipelines. 展开更多
关键词 Radio synthesis ARRAYS Square kilometre array WIDE ?eld IMAGING PARALLELIZATION w-Projection
上一页 1 2 250 下一页 到第
使用帮助 返回顶部 意见反馈