期刊文献+
共找到39篇文章
< 1 2 >
每页显示 20 50 100
A machine learning-based strategy for predicting the mechanical strength of coral reef limestone using X-ray computed tomography
1
作者 Kai Wu Qingshan Meng +4 位作者 Ruoxin Li Le Luo Qin Ke ChiWang Chenghao Ma 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2790-2800,共11页
Different sedimentary zones in coral reefs lead to significant anisotropy in the pore structure of coral reef limestone(CRL),making it difficult to study mechanical behaviors.With X-ray computed tomography(CT),112 CRL... Different sedimentary zones in coral reefs lead to significant anisotropy in the pore structure of coral reef limestone(CRL),making it difficult to study mechanical behaviors.With X-ray computed tomography(CT),112 CRL samples were utilized for training the support vector machine(SVM)-,random forest(RF)-,and back propagation neural network(BPNN)-based models,respectively.Simultaneously,the machine learning model was embedded into genetic algorithm(GA)for parameter optimization to effectively predict uniaxial compressive strength(UCS)of CRL.Results indicate that the BPNN model with five hidden layers presents the best training effect in the data set of CRL.The SVM-based model shows a tendency to overfitting in the training set and poor generalization ability in the testing set.The RF-based model is suitable for training CRL samples with large data.Analysis of Pearson correlation coefficient matrix and the percentage increment method of performance metrics shows that the dry density,pore structure,and porosity of CRL are strongly correlated to UCS.However,the P-wave velocity is almost uncorrelated to the UCS,which is significantly distinct from the law for homogenous geomaterials.In addition,the pore tensor proposed in this paper can effectively reflect the pore structure of coral framework limestone(CFL)and coral boulder limestone(CBL),realizing the quantitative characterization of the heterogeneity and anisotropy of pore.The pore tensor provides a feasible idea to establish the relationship between pore structure and mechanical behavior of CRL. 展开更多
关键词 Coral reef limestone(CRL) Machine learning Pore tensor x-ray computed tomography(ct)
下载PDF
Predictive Factors of the Presence and Number of Noncalcified Coronary Plaque in Japanese Patients with Zero Coronary Artery Calcium Score Using 64-Slice Multi-Detector Computed Tomography
2
作者 Yoshiki Noda Ryo Matsutera +8 位作者 Yoshinori Yasuoka Kiyoshi Kume Hidenori Adachi Susumu Hattori Ryo Araki Motohiro Kosugi Yasuaki Kohama Tetsufumi Nakashima Tatsuya Sasaki 《Advances in Computed Tomography》 2013年第3期112-120,共9页
Background: Factors that can predict the presence and number of noncalcified coronary plaques (NCP) in Japanese patients with zero coronary artery calcium scores (CACS) essentially remain undefined. Methods and Result... Background: Factors that can predict the presence and number of noncalcified coronary plaques (NCP) in Japanese patients with zero coronary artery calcium scores (CACS) essentially remain undefined. Methods and Results: We assessed independent predictors of the presence and number of segments with NCP in 111 Japanese patients with zero CACS who underwent 64-slice multi-detector computed tomography at our hospital. Thirty five patients (32%) had NCP, and 24 patients (22%) had ≥ 2 NCPs. Multiple logistic regression analysis revealed that significant predictors for the presence of NCP were age (odds ratio [OR]: 1.06, 95% confidence interval [CI] 1.01 - 1.11, p = 0.021), male (OR: 3.61, 95% CI 1.40 - 9.35, p = 0.008) and diabetes mellitus (OR: 3.10, 95% CI 1.02 - 9.45, p = 0.046), and those for the presence of ≥ 2 NCPs were age (OR: 1.08, 95% CI 1.02 - 1.15, p = 0.007) and a current smoking habit (OR: 5.09, 95% CI 1.00 - 25.74, p = 0.049). Multiple linear regression analysis identified advanced age, male gender and diabetes mellitus as independent predictors of the number of NCPs. A novel score calculated from the above four predictors showed moderate accuracy for a diagnosis of NCP and ≥ 2 NCPs, with areas under receiver operating curves of 0.738 and 0.736, respectively. Conclusions: Male Japanese patients with zero CACS, advanced age, diabetes mellitus and a current smoking habit might have NCPs. 展开更多
关键词 ZERO CORONARY Artery Calcium Score NUMBER of Noncalcified CORONARY PLAQUE 64-slice Multi-Detector computed tomography Japanese Patients
下载PDF
Assessing efficacy of standard impregnation techniques on die-cast aluminum alloys using X-ray micro-CT
3
作者 Ajith Bandara Koichi Kan +3 位作者 Katanaga Yusuke Natsuto Soga Akifumi Koike Toru Aoki 《China Foundry》 SCIE EI CAS CSCD 2024年第3期276-286,共11页
Utilizing lightweight Al alloys in various industrial applications requires achieving precise pressure tightness and leak requirements.Vacuum pressure impregnation(VPI)with thermosetting polymers is commonly used to a... Utilizing lightweight Al alloys in various industrial applications requires achieving precise pressure tightness and leak requirements.Vacuum pressure impregnation(VPI)with thermosetting polymers is commonly used to address leakage defects in die-cast Al alloys.In this study,the efficacy of the VPI technique in sealing alloy parts was investigated using a combination of nondestructive micro X-ray computed tomography(micro XCT)and a standard leak test.The results demonstrate that the commonly used water leak test is insufficient for determining the sealing performance.Instead,micro XCT shows distinct advantages by enabling more comprehensive analysis.It reveals the presence of a low atomic number impregnates sealant within casting defects,which has low grey contrast and allows for visualizing primary leakage paths in 3D.The effective atomic number of impregnated resin is 6.75 and that of Al alloy is 13.69 by dual-energy X-ray CT.This research findings will contribute to enhancing the standard VPI process parameters and the properties of impregnating sealants to improve quality assurance for impregnation in industrial metals. 展开更多
关键词 nondestructive testing Al alloy die-casting vacuum pressure impregnation micro x-ray computed tomography duel-energy x-ray ct
下载PDF
Usefulness of Chest Computed Tomography for Diagnosis of Idiopathic Pneumomediastinum with Negative Findings on Plain X-Ray
4
作者 Kazuhiro Mino Tadao Okada +2 位作者 Shohei Honda Hisayuki Miyagi Akinobu Taketomi 《Surgical Science》 2012年第4期216-219,共4页
Idiopathic pneumomediastinum is rare in children. Few cases of patients with pneumomediastinum show negative findings on X-ray examination. Chest computed tomography (CT) was very useful for the diagnosis and evaluati... Idiopathic pneumomediastinum is rare in children. Few cases of patients with pneumomediastinum show negative findings on X-ray examination. Chest computed tomography (CT) was very useful for the diagnosis and evaluation of the extent of pneumomediastinum. We report here a case of idiopathic pneumomediastinum in a 15-year-old boy who exhibited no significant chest X-ray finding. The patient was referred to our institute for the further evaluation of pre-cordial pain and breathing difficulty. Precordial pain suddenly developed, when he was carrying a portable shrine on his shoulder (day of onset). He was admitted to another institute 3 days after onset because of worsening precordial pain. On admission, he presented with 98% saturation of hemoglobin in the peripheral blood under room air. Plain chest X-ray also revealed no abnormal findings. A half-dissolved gastrographin swallow showed no leakage of gastrographin from the pharynx and esophagus to the mediastinum, and no diverticulum within the esophagus. Plain chest CT revealed extensive emphysema around the trachea from the neck to the portion inferior to the carina of trachea. The patient was diagnosed with idiopathic pneumomediastinum because the cause was unclear. We decided to admit him to our institute under fasting conditions and rest. His symptoms improved 3 days after onset. The lesion had disap-peared 8 days after onset on chest CT. When young people experience precordial pain which increases on inspiration, we must consider pneumomediastinum in a differential diagnosis, and it is important to perform chest CT. 展开更多
关键词 CHEST x-ray Child computed tomography (ct) IDIOPATHIC PNEUMOMEDIASTINUM
下载PDF
Experimental investigation of junction growth of rough contacts using X-ray computed tomography
5
作者 Runliang WANG Jianhua LIU +2 位作者 Bo LIU Duo JIA Xiaoyu DING 《Friction》 SCIE EI CAS CSCD 2024年第11期2519-2531,共13页
The real contact area(RCA)of randomly rough contacts has received a great deal of attention because it correlates strongly with friction,lubrication,sealing,and conductivity.Simulations have revealed that the RCA asso... The real contact area(RCA)of randomly rough contacts has received a great deal of attention because it correlates strongly with friction,lubrication,sealing,and conductivity.Simulations have revealed that the RCA associated with deterministic normal squeezing loads increases when tangential loads are also applied,in a phenomenon called junction growth.However,experimental investigations of the junction growth of randomly rough contacts are rare.Here,we used X-ray computed tomography(CT)to measure junction growth when two aluminum alloy surfaces were in contact.A high-resolution experimental setup was used to apply loads and observe contact behaviors at a resolution of 4μm.The RCA and average contact gaps were computed using a three-dimensional(3D)geometric model constructed from gray CT images using the Otsu thresholding method.The results showed that the RCA increased as the normal load increased.The RCA increased by 22.67%after a tangential load was applied(junction growth),and the average gap decreased by 14.01%after a tangential load was applied.Thus,X-ray CT accurately measured the junction growth as a novel quantitative method. 展开更多
关键词 three-dimensional(3D)contact analyses real contact area(RCA) junction growth x-ray computed tomography(ct) assembly interfaces
原文传递
Observation of the effect of targeted therapy of 64-slice spiral CT combined with cryoablation for liver cancer 被引量:23
6
作者 Qiao-Huan Yan Dian-Guo Xu +4 位作者 Yan-Feng Shen Ding-Ling Yuan Jun-Hui Bao Hai-Bin Li Ying-Gang Lv 《World Journal of Gastroenterology》 SCIE CAS 2017年第22期4080-4089,共10页
AIM to observe the effect of targeted therapy with 64-slice spiral computed tomography (CT) combined with cryoablation for liver cancer. METHODS A total of 124 patients ( 142 tumors) were enrolled into this study. Acc... AIM to observe the effect of targeted therapy with 64-slice spiral computed tomography (CT) combined with cryoablation for liver cancer. METHODS A total of 124 patients ( 142 tumors) were enrolled into this study. According to the use of dual-slice spiral CT or 64-slice spiral CT as a guide technology, patients were divided into two groups: dual-slice group (n = 56, 65 tumors) and 64-slice group (n = 8, 77 tumors). All patients were accepted and received targeted therapy by an argon-helium superconducting surgery system. The guided scan times of the two groups was recorded and compared. In the two groups, the lesion ice coverage in diameter of >= 3 cm and < 3 cm were recorded, and freezing effective rate was compared. Hepatic perfusion values [ hepatic artery perfusion (HAP), portal vein perfusion (PVP), and the hepatic arterial perfusion index (HAPI)] of tumor tissues, adjacent tissues and normal liver tissues at preoperative and postoperative four weeks in the two groups were compared. Local tumor changes were recorded and efficiency was compared at four weeks post-operation. Adverse events were recorded and compared between the two groups, including fever, pain, frostbite, nausea, vomiting, pleural effusion and abdominal bleeding. RESULTS Guided scan times in the dual-slice group was longer than that in the 64-slice group (t = 11.445, P = 0.000). The freezing effective rate for tumors < 3 cm in diameter in the dual-slice group (81.58%) was lower than that in the 64-slice group (92.86%) (chi(2) = 5.707, P = 0.017). The HAP and HAPI of tumor tissues were lower at four weeks post-treatment than at pretreatment in both groups (all P < 0.05), and those in the 64-slice group were lower than that in the dual-slice group ( all P < 0.05). HAP and PVP were lower and HAPI was higher in tumor adjacent tissues at post-treatment than at pre-treatment ( all P < 0.05). Furthermore, the treatment effect and therapeutic efficacy in the dual-slice group were lower than the 64-slice group at four weeks post-treatment (all P < 0.05). Moreover, pleural effusion and intraperitoneal hemorrhage occurred in patients in the dual-slice group, while no complications occurred in the 64-slice group (all P < 0.05). CONCLUSION 64-slice spiral CT applied with cryoablation in targeted therapy for liver cancer can achieve a safe and effective freezing treatment, so it is worth being used. 展开更多
关键词 64-slice spiral computed tomography CRYOABLATION Liver cancer
下载PDF
Three-dimensional finite element simulation and reconstruction of jointed rock models using CT scanning and photogrammetry
7
作者 Yingxian Lang Zhengzhao Liang Zhuo Dong 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1348-1361,共14页
The geometry of joints has a significant influence on the mechanical properties of rocks.To simplify the curved joint shapes in rocks,the joint shape is usually treated as straight lines or planes in most laboratory e... The geometry of joints has a significant influence on the mechanical properties of rocks.To simplify the curved joint shapes in rocks,the joint shape is usually treated as straight lines or planes in most laboratory experiments and numerical simulations.In this study,the computerized tomography (CT) scanning and photogrammetry were employed to obtain the internal and surface joint structures of a limestone sample,respectively.To describe the joint geometry,the edge detection algorithms and a three-dimensional (3D) matrix mapping method were applied to reconstruct CT-based and photogrammetry-based jointed rock models.For comparison tests,the numerical uniaxial compression tests were conducted on an intact rock sample and a sample with a joint simplified to a plane using the parallel computing method.The results indicate that the mechanical characteristics and failure process of jointed rocks are significantly affected by the geometry of joints.The presence of joints reduces the uniaxial compressive strength (UCS),elastic modulus,and released acoustic emission (AE) energy of rocks by 37%–67%,21%–24%,and 52%–90%,respectively.Compared to the simplified joint sample,the proposed photogrammetry-based numerical model makes the most of the limited geometry information of joints.The UCS,accumulative released AE energy,and elastic modulus of the photogrammetry-based sample were found to be very close to those of the CT-based sample.The UCS value of the simplified joint sample (i.e.38.5 MPa) is much lower than that of the CT-based sample (i.e.72.3 MPa).Additionally,the accumulative released AE energy observed in the simplified joint sample is 3.899 times lower than that observed in the CT-based sample.CT scanning provides a reliable means to visualize the joints in rocks,which can be used to verify the reliability of photogrammetry techniques.The application of the photogrammetry-based sample enables detailed analysis for estimating the mechanical properties of jointed rocks. 展开更多
关键词 x-ray computerized tomography(ct)scanning PHOTOGRAMMETRY Parallel computing Numerical simulation Uniaxial compression test Digital image processing
下载PDF
Investigation of noise properties in grating-based x-ray phase tomography with reverse projection method
8
作者 鲍园 王研 +3 位作者 高昆 王志立 朱佩平 吴自玉 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期622-628,共7页
The relationship between noise variance and spatial resolution in grating-based x-ray phase computed tomography(PCT) imaging is investigated with reverse projection extraction method, and the noise variances of the ... The relationship between noise variance and spatial resolution in grating-based x-ray phase computed tomography(PCT) imaging is investigated with reverse projection extraction method, and the noise variances of the reconstructed absorption coefficient and refractive index decrement are compared. For the differential phase contrast method, the noise variance in the differential projection images follows the same inverse-square law with spatial resolution as in conventional absorption-based x-ray imaging projections. However, both theoretical analysis and simulations demonstrate that in PCT the noise variance of the reconstructed refractive index decrement scales with spatial resolution follows an inverse linear relationship at fixed slice thickness, while the noise variance of the reconstructed absorption coefficient conforms with the inverse cubic law. The results indicate that, for the same noise variance level, PCT imaging may enable higher spatial resolution than conventional absorption computed tomography(ACT), while ACT benefits more from degraded spatial resolution. This could be a useful guidance in imaging the inner structure of the sample in higher spatial resolution. 展开更多
关键词 x-ray imaging noise variance spatial resolution computed tomography ct
下载PDF
64排CT诊断肠壁缺血性病变的诊断价值及临床意义分析 被引量:13
9
作者 张凯 童三龙 +2 位作者 雷鸣峰 黎钧 徐应辉 《中国CT和MRI杂志》 2015年第3期87-89,共3页
目的研究64排CT对肠壁缺血性病变的临床诊断价值及意义。方法回顾性分析2013年11月-2014年11月住院部及门诊部收治的32例肠壁缺血性病变患者的CT诊断结果、临床资料等,并与临床病理组织检查结果进行对比,以判断CT的诊断价值。结果临床... 目的研究64排CT对肠壁缺血性病变的临床诊断价值及意义。方法回顾性分析2013年11月-2014年11月住院部及门诊部收治的32例肠壁缺血性病变患者的CT诊断结果、临床资料等,并与临床病理组织检查结果进行对比,以判断CT的诊断价值。结果临床病理诊断患者肠系膜下动脉狭窄占50.00%,肠系膜上、下动脉均狭窄占31.25%,腹主动脉狭窄占18.75%;64排CT诊断分别为46.88%、28.12%、21.88%。以临床病理诊断为标准,64排CT诊断的灵敏度为90.63%、准确率为96.88%、特异性为87.5%;准确率与临床病理诊断比较无明显差异;灵敏度和特异性与临床病理诊断比较χ2=9.37、12.70;P<0.05,差异具有统计学意义。结论 64排CT对肠壁缺血性病变的临床诊断率高,且无创、及时、安全性高,具有较高的临床使用价值和实践意义。 展开更多
关键词 64ct 肠壁缺血性病变 诊断价值
下载PDF
Biograph 64 TruePoint PET/CT的主要技术参数及应用 被引量:2
10
作者 李培秀 王国军 +1 位作者 张俊权 姜杉 《医疗卫生装备》 CAS 2008年第10期104-105,107,共3页
对PET/CT设备的基本结构、主要参数及其在肿瘤系统、心血管系统和神经系统中的临床应用价值进行了简要介绍。64层PET/CT在冠心病诊断和治疗指导中具有特别的意义,它可将18F-FDG的PET心肌代谢与64层CT冠脉成像同机同时进行,确定心肌活性... 对PET/CT设备的基本结构、主要参数及其在肿瘤系统、心血管系统和神经系统中的临床应用价值进行了简要介绍。64层PET/CT在冠心病诊断和治疗指导中具有特别的意义,它可将18F-FDG的PET心肌代谢与64层CT冠脉成像同机同时进行,确定心肌活性及供血冠状动脉分布,对治疗方案的选择起决定性作用。 展开更多
关键词 64ct 52环PET 心肌代谢显像 体层摄影术 X线计算机 体层摄影术 发射型计算机
下载PDF
64层螺旋CT血管成像技术在头颈部血管病变诊断的研究 被引量:9
11
作者 周宏 曾自三 《广西医科大学学报》 CAS 2010年第3期403-405,共3页
目的:探讨64层螺旋CT血管成像(CTA)技术对于头颈部血管病变的诊断价值。方法:100例疑似头颈部血管病变的患者行64层CT血管成像,且应用同步减影技术(ssCTA)。扫描数据在AW4.3后处理工作站上使用各种不同技术进行后处理。结果:100例患者... 目的:探讨64层螺旋CT血管成像(CTA)技术对于头颈部血管病变的诊断价值。方法:100例疑似头颈部血管病变的患者行64层CT血管成像,且应用同步减影技术(ssCTA)。扫描数据在AW4.3后处理工作站上使用各种不同技术进行后处理。结果:100例患者的双侧颈总动脉、颈内动脉、椎动脉、大脑前动脉、大脑中动脉、大脑后动脉、大脑后动脉及Willis环均能显示,共检出狭窄142段,闭塞26段,动脉瘤11例,血管起点变异15例,血管正常患者17例。结论:64层螺旋CT血管成像技术应用于临床初步诊断,并且头颈部CTA能够成为头颈部血管疾病的首要检查及主要筛选方法。 展开更多
关键词 血管成像 头颈部 64层螺旋ct
下载PDF
64层螺旋CT三维血管成像在主动脉夹层诊断中的价值 被引量:1
12
作者 袁红梅 余建群 +2 位作者 张优仪 原珍团 褚志刚 《山东医药》 CAS 北大核心 2008年第26期36-38,共3页
目的探讨64层螺旋CT三维血管成像在主动脉夹层诊断中的价值。方法对34例主动脉夹层(AD)患者行64层螺旋CT薄层扫描,在工作站采用最大密度投影(MIP)、多平面重建(MPR)及容积再现(VRT)技术对轴位图像进行三维重建。结果34例AD中显示真假腔3... 目的探讨64层螺旋CT三维血管成像在主动脉夹层诊断中的价值。方法对34例主动脉夹层(AD)患者行64层螺旋CT薄层扫描,在工作站采用最大密度投影(MIP)、多平面重建(MPR)及容积再现(VRT)技术对轴位图像进行三维重建。结果34例AD中显示真假腔34例,内膜片27例,壁内血肿7例;27例典型夹层三维成像均显示明确破口,主动脉弓部破口以矢状位显示最佳,降主动脉破口以轴位及冠状显示最佳,VRT显示病变全程较清晰,但对破口及内膜片的显示不如MIP、MPR及轴位。结论64层螺旋CT三维血管成像能全面清晰显示AD解剖病理改变,尤其是对破口的显示,是AD的重要诊断手段。 展开更多
关键词 主动脉夹层 螺旋ct 64 三维成像
下载PDF
脂肪肝患者64层螺旋CT灌注成像的研究 被引量:1
13
作者 王燕 朱建新 张金华 《实用临床医药杂志》 CAS 2012年第15期79-81,共3页
目的采用64层螺旋CT灌注技术测定脂肪肝患者的血流灌注参数的变化,分析其血流动力学的改变。方法 64层螺旋CT肝血流灌注成像15例,其中脂肪肝患者13例,健康志愿者2例,观察分析肝脏血流灌注各参数。结果脂肪肝患者的血流灌注参数与正常组... 目的采用64层螺旋CT灌注技术测定脂肪肝患者的血流灌注参数的变化,分析其血流动力学的改变。方法 64层螺旋CT肝血流灌注成像15例,其中脂肪肝患者13例,健康志愿者2例,观察分析肝脏血流灌注各参数。结果脂肪肝患者的血流灌注参数与正常组组间相比,肝动脉灌注值(Art.Perf)、肝门静脉灌注值(Port.Perf)、总灌注值(Tortal.Perf)下降程度明显;随着脂肪肝组组内病变严重度增加,Art.Perf与Tortal.Perf参数值亦有明显下降;肝动脉灌注指数(HPI)值各组无明显相关性。结论肝脏CT灌注成像可反映脂肪肝的血流改变,并且对脂肪肝患者的血供情况加以评估,为临床提供更多的诊断依据。 展开更多
关键词 脂肪肝 体层摄影术X线计算机 64层螺旋ct 灌注成像
下载PDF
隐匿性骨折应用64排CT与1.5T磁共振的诊断价值对照 被引量:7
14
作者 覃延 《当代医学》 2018年第12期28-30,共3页
目的隐匿性骨折应用64排CT与1.5T磁共振的诊断价值对照研究。方法选择本院2016年7月~2017年7月收治的64例隐匿性骨折患者,按照患者检查方式将其分成CT组和MRI组,每组32例,CT组患者检查过程中应用64排CT进行诊断,MRI组患者检查过程中应用... 目的隐匿性骨折应用64排CT与1.5T磁共振的诊断价值对照研究。方法选择本院2016年7月~2017年7月收治的64例隐匿性骨折患者,按照患者检查方式将其分成CT组和MRI组,每组32例,CT组患者检查过程中应用64排CT进行诊断,MRI组患者检查过程中应用1.5T磁共振进行诊断,对比两种诊断方式诊断效果。结果 CT组患者骨折检出率为78.13%,MRI组患者骨折检出率为96.88%,组间对比MRI组检出率明显的高于CT组,数据差异具有统计学意义(P<0.05)。CT患者在进行CT检查之后检查结果显示,单一横断面骨折患者一共有24例(75.00%),横断三维重建骨折患者则有8例(25.00%);MRI组患者在经过磁共振检查之后检查结果显示出骨折患者一共有31例(96.88%),T1W1图像则提示患者骨质存在不规则线状以及条状等低信号,T2W1、压脂序列图像则提示存在高信号。结论隐匿性骨折临床诊断过程中,应用1.5T磁共振价值高于64排CT,检出率更高,可以在临床诊断过程中优先考虑。 展开更多
关键词 隐匿性骨折 64ct 1.5T磁共振 诊断价值
下载PDF
个体化低剂量扫描在64排CT冠状动脉成像中的临床研究
15
作者 侯铁 邓玉云 +4 位作者 杨光 赵素岗 姜涛 朱崇磊 王云成 《中国继续医学教育》 2016年第3期72-73,共2页
目的分析个体化低剂量扫描在64排CT冠状动脉成像中的临床情况。方法随机抽取2012年2月~2013年6月诊治的100例使用64-MDCT进行检查患者,分为研究组和对比组,每组50例患者,研究组50例患者使用个体化前瞻性心电门控扫描,对比组50例患者个... 目的分析个体化低剂量扫描在64排CT冠状动脉成像中的临床情况。方法随机抽取2012年2月~2013年6月诊治的100例使用64-MDCT进行检查患者,分为研究组和对比组,每组50例患者,研究组50例患者使用个体化前瞻性心电门控扫描,对比组50例患者个体化回顾性心电门控扫描,分析两组的扫描情况。结果研究组的检查情况优于对比组,两者间的差异具备统计学意义(P〈0.05)。结论最好的个体化低剂量扫描方法是:使用个体化前瞻性心电门控扫描,然后把心率控制为小于65次/min,这样不仅可以提高图像质量,可以有效减少对患者的辐射伤害,确保患者安全。 展开更多
关键词 个体化 低剂量 64ct 冠状动脉成像
下载PDF
Brilliance型64排螺旋CT数据采集系统常见故障及维修保养 被引量:14
16
作者 杨寻柱 王佳敏 《中国医学装备》 2020年第7期192-194,共3页
通过分析Brilliance型64排螺旋CT数据采集系统常见故障和维修保养方法,达到维持设备良好性能、提高工作效率以及降低设备故障和减少维修成本的目的。总结螺旋CT数据采集系统常见故障及保养方法,以减少设备故障发生,确保其正常运行。定... 通过分析Brilliance型64排螺旋CT数据采集系统常见故障和维修保养方法,达到维持设备良好性能、提高工作效率以及降低设备故障和减少维修成本的目的。总结螺旋CT数据采集系统常见故障及保养方法,以减少设备故障发生,确保其正常运行。定期对螺旋CT进行维护与保养,设备总体运行良好,故障发生率显著降低。放射科工程技术工作人员需重视螺旋CT数据采集系统常见故障及日常维修保养,排除数据采集系统可能出现的问题,减少故障发生,维持设备性能,延长其使用寿命。 展开更多
关键词 64排螺旋ct 数据采集系统 故障 维修 保养
下载PDF
后64排螺旋CT冠脉检查新进展 被引量:9
17
作者 赵义芹 祖德贵 曾庆玉 《CT理论与应用研究(中英文)》 2012年第1期149-155,共7页
64排CT冠状动脉成像已成为冠脉病变诊断及筛查的重要无创性检查,但心律不齐、心动过速、钙化支架伪影仍影响其冠脉成像质量以及辐射剂量过高。本文总结了后64排CT如双源CT、Brilliance ICT、宝石CT、320排CT在上述检查中取得的进展和仍... 64排CT冠状动脉成像已成为冠脉病变诊断及筛查的重要无创性检查,但心律不齐、心动过速、钙化支架伪影仍影响其冠脉成像质量以及辐射剂量过高。本文总结了后64排CT如双源CT、Brilliance ICT、宝石CT、320排CT在上述检查中取得的进展和仍然存在的不足,表明后64排CT的辐射剂量均有所减低,双源CT、Brilliance ICT随着时间分辨率的提高基本上解决了心动过速的问题,320排CT根本上解决了心律不齐的问题,并对后64排螺旋CT冠脉检查的发展前景进行讨论。 展开更多
关键词 计算机断层成像 冠状动脉 64ct
下载PDF
鼻窦CT评分联合特异性免疫球蛋白E和白细胞介素6预测嗜酸粒细胞型慢性鼻窦炎伴鼻息肉患者术后复发风险的价值 被引量:2
18
作者 胡焱 陈剑波 《中国耳鼻咽喉头颈外科》 CSCD 2023年第8期529-532,共4页
目的探讨鼻窦CT评分联合特异性免疫球蛋白E(sIgE)和白细胞介素6(IL-6)对嗜酸粒细胞型慢性鼻窦炎伴鼻息肉(ECRSwNP)患者术后复发风险的预测价值。方法选取2019年1月~2022年1月浙江大学医学院附属杭州西溪医院收治的ECRSwNP患者92例,均行... 目的探讨鼻窦CT评分联合特异性免疫球蛋白E(sIgE)和白细胞介素6(IL-6)对嗜酸粒细胞型慢性鼻窦炎伴鼻息肉(ECRSwNP)患者术后复发风险的预测价值。方法选取2019年1月~2022年1月浙江大学医学院附属杭州西溪医院收治的ECRSwNP患者92例,均行功能性鼻内镜手术,根据术后1年复发情况分为复发组(n=29)和未复发组(n=63)。比较两组鼻窦CT评分,并采用Pearson相关性分析法分析外周血嗜酸粒细胞(Eos)及组织Eos百分比(Eos%)与鼻窦CT评分的相关性;利用Logistic回归分析模型分析术后复发的危险因素,用受试者工作特征曲线(ROC)及曲线下面积(AUC)探究鼻窦CT评分、特异性免疫球蛋白E(sIgE)、IL-6对患者术后复发的预测价值。结果复发组前组筛窦评分、后组筛窦评分、鼻窦CT评分及筛窦与上颌窦评分比值(E/M比)均大于未复发组(P<0.05);组织Eos%与前组筛窦评分、后组筛窦评分及E/M比均呈正相关(r=0.305、0.381、0.642,P均<0.05),外周血Eos%与前组筛窦评分、后组筛窦评分及E/M比亦呈正相关(r=0.272、0.346、0.525,P均<0.05)。复发组哮喘患者占比、鼻塞视觉模拟量表(VAS)评分、组织Eos%、外周血Eos%及sIgE、IL-6水平均高于未复发组(P<0.05),组织中性粒细胞百分比(Neu%)、外周血Neu%则低于未复发组(P<0.05);Logistic分析显示,高水平血清sIgE、IL-6及高E/M比均是影响患者术后复发的危险因素(P<0.05)。ROC曲线分析显示,血清sIgE、IL-6、E/M比及三者联合预测ECRSwNP患者术后复发风险的AUC分别为0.818、0.758、0.696、0.915,三项指标联合预测效能高于单项检测(P<0.05)。结论高水平血清sIgE、IL-6及高E/M比是ECRSwNP患者术后复发的危险因素,三者联合预测患者鼻内镜术后复发风险具有较高临床价值。 展开更多
关键词 鼻窦炎(Sinusitis) 鼻息肉(Nasal Polyps) 嗜酸细胞(Eosinophils) 白细胞介素6(Interleukin-6) 复发(Recidivism) ct Lund-Mackay score(Lund-Mackay ct评分) 特异性免疫球蛋白(specific immunoglobulin E) 体层摄影扫描仪 X线计算机(tomography Scanners x-ray computed)
下载PDF
64排螺旋CT不同探测通道组合在婴幼儿中的模拟应用研究 被引量:1
19
作者 李建明 周思茵 黄赛威 《中国医疗设备》 2020年第3期92-95,共4页
目的探讨64排螺旋CT不同探测通道组合在婴幼儿中的应用价值。方法按3、10和20 cm的扫描长度将研究分成Ⅰ、Ⅱ、Ⅲ组,运用不同探测通道组合分组扫描QA检测模,分析不同通道组合的辐射剂量、图像质量和扫描时间。结果Ⅰ组剂量长度乘积的最... 目的探讨64排螺旋CT不同探测通道组合在婴幼儿中的应用价值。方法按3、10和20 cm的扫描长度将研究分成Ⅰ、Ⅱ、Ⅲ组,运用不同探测通道组合分组扫描QA检测模,分析不同通道组合的辐射剂量、图像质量和扫描时间。结果Ⅰ组剂量长度乘积的最小值(107.40 mGy·cm)出现在16排×0.5 mm通道组合,Ⅱ、Ⅲ组均出现在16排×1.0 mm通道组合(243.50、423.90 mGy·cm);三组DLP的最大值均出现在4排×0.5 mm通道组合,Ⅱ、Ⅲ组中的64排×0.5 mm通道组合次之。三组各通道组合中水CT值的测量值均值为-3.1^+3.5 HU。三组扫描速度最快均为16排×2.0 mm通道组合,最慢均为4排×0.5 mm通道组合。结论64排螺旋CT 16排×1.0 mm通道组合有利于婴幼儿CT检查辐射剂量和图像质量的最优化;4排×0.5 mm通道组合辐射剂量大、扫描时间长,不适宜向临床推广应用。 展开更多
关键词 64排螺旋ct 体层摄影术 X线计算机 探测通道 婴幼儿
下载PDF
急性冠状动脉综合征64层螺旋CT血管造影特点分析 被引量:2
20
作者 张亦辉 包太成 彭梅 《现代医药卫生》 2013年第12期1791-1792,共2页
目的利用64层螺旋CT血管造影(CTA)分析急性冠状动脉综合征(ACS)患者冠状动脉病变特点。方法将2012年1—10月在该院住院、行心脏CTA的82例冠心病患者分为两组:ACS组35例和稳定型心绞痛(SAP)组47例,计算两组不同性质斑块数目。结果 82例... 目的利用64层螺旋CT血管造影(CTA)分析急性冠状动脉综合征(ACS)患者冠状动脉病变特点。方法将2012年1—10月在该院住院、行心脏CTA的82例冠心病患者分为两组:ACS组35例和稳定型心绞痛(SAP)组47例,计算两组不同性质斑块数目。结果 82例冠心病患者中,ACS组检出:软斑块42个,中等密度斑块21个,钙化斑块31个,混合斑块33个;SAP组检出:软斑块13个,中等密度斑块49个,钙化斑块63个,混合斑块21个。ACS组不稳定斑块占59.06%(75/127),SAP组不稳定斑块占23.29%(34/146),两组比较,差异有统计学意义(P<0.05)。结论相对于SAP患者,ACS患者冠状动脉粥样斑块以不稳定斑块为主,这构成了该病的病理基础。 展开更多
关键词 冠状血管 冠状血管造影术 急性冠状动脉综合征 体层摄影术 螺旋计算机 64层螺旋ct 动脉斑块
下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部