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多层螺旋CT图像后处理技术对腰椎峡部裂的诊断价值 被引量:16
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作者 谢元忠 孔庆奎 +2 位作者 公维云 张立涛 崔群生 《中国脊柱脊髓杂志》 CAS CSCD 2008年第7期526-529,共4页
目的:探讨多层螺旋CT图像后处理技术对腰椎峡部裂的诊断价值。方法:应用多层螺旋CT机对43例腰椎峡部裂患者的腰椎进行扫描,利用多平面重建(MPR)、最大密度投影(MIP)、容积显示技术(VRT)进行多模式图像后处理,多方位观察患者椎弓峡部裂... 目的:探讨多层螺旋CT图像后处理技术对腰椎峡部裂的诊断价值。方法:应用多层螺旋CT机对43例腰椎峡部裂患者的腰椎进行扫描,利用多平面重建(MPR)、最大密度投影(MIP)、容积显示技术(VRT)进行多模式图像后处理,多方位观察患者椎弓峡部裂情况。结果:43例患者中共发现83个椎弓峡部裂,双侧32例,其中4例累及两个脊椎的双侧椎弓;单侧11例。腰椎斜矢状位MPR及平行于椎弓的轴位MPR能够诊断全部病例,13例裂隙呈不规则锯齿状,边缘清晰,9例边缘骨质硬化、膨大;12例伴有碎骨块,并见裂隙周围纤维组织增生。正中矢状位MPR发现脊椎向前滑脱22例,其中Ⅰ度滑脱16例,Ⅱ度滑脱5例,Ⅲ度滑脱1例。7例出现假性椎间盘膨出征,硬膜囊向前移行。MIP也能全部显示所有病例的峡部裂,但是对软组织观察不如MPR。高密度VRT仅发现峡部裂23例39处。结论:多层螺旋CT扫描后MPR、MIP及VRT图像后处理技术能够全方位评价腰椎峡部裂的形态变化,为临床提供与峡部裂有关的更多更详细的影像信息,MPR是最有价值的重建方法。 展开更多
关键词 腰椎峡部裂 多层螺旋CT扫描 多平面重建 最大密度投影 容积成像
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Value of section plane,MPR,and 3D-CTVR techniques in the fine differential diagnosis of ossicular chain in the case of conductive hearing loss with intact tympanic membrane 被引量:6
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作者 Yang Liu Feng Yang +1 位作者 QiaoHui Lu Danheng Zhao 《Journal of Otology》 CSCD 2017年第2期80-85,共6页
Aim: To assess the quality of high-resolution CT section planes(HRCT), multi-planar reformation(MPR) and 3-dimensional volume rendered computer tomography(3D-CTVR) were here used in the fine differential diagnosis of ... Aim: To assess the quality of high-resolution CT section planes(HRCT), multi-planar reformation(MPR) and 3-dimensional volume rendered computer tomography(3D-CTVR) were here used in the fine differential diagnosis of ossicular chain in the case of conductive hearing loss with intact tympanic membrane.Methods: Here, 17 cases of otosclerosis and 22 cases of ossicular chain deformity were selected. All patients had normal external ear canals,intact tympanic membranes, conductive hearing loss, type A tympanograms, and negative Gelle's tests. The respective radiological reports of the status of the ossicles via 3 protocols were compared to surgical findings. The quantitative assessments of the representation of different segments of the ossicular chain were based on a 3-point scoring system.Results: MPR and CTVR imaging both showed the integrity of whole ossicular chain well. MPR and CTVR imaging were found to be superior to section planes with respect to showing the superstructure of the stapes and malformations(P > 0.05).Conclusion: CTVR and MPR imaging were found to be better able to show the whole ossicular chain in the conductive hearing loss with normal tympanic membranes. Furthermore, the use of these techniques can have profound contributive value in the differential diagnosis of otosclerosis and ossicular chain absence or malformation. 展开更多
关键词 Ossicular chain Conductive hearing loss Volume rendered computer tomography multi-planar REFORMATION SECTION pla
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Stress Concentration Factors at Saddle and Crown Positions on the Central Brace of Two-Planar Welded CHS DKT-connections 被引量:2
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作者 Hamid Ahmadi Mohammad Ali Lotfollahi-Yaghin Mohammad H. Aminfar 《Journal of Marine Science and Application》 2012年第1期83-97,共15页
A set of parametric stress analyses was carried out for two-planar tubular DKT-joints under different axial loading conditions. The analysis results were used to present general remarks on the effects of the geometric... A set of parametric stress analyses was carried out for two-planar tubular DKT-joints under different axial loading conditions. The analysis results were used to present general remarks on the effects of the geometrical parameters on stress concentration factors (SCFs) at the inner saddle, outer saddle, and crown positions on the central brace. Based on results of finite element (FE) analysis and through nonlinear regression analysis, a new set of SCF parametric equations was established for fatigue design purposes. An assessment study of equations was conducted against the experimental data and original SCF database. The satisfaction of acceptance criteria proposed by the UK Department of Energy (UK DoE) was also checked. Results of parametric study showed that highly remarkable differences exist between the SCF values in a multi-planar DKT-joint and the corresponding SCFs in an equivalent uni-planar KT-joint having the same geometrical properties. It can be clearly concluded from this observation that using the equations proposed for uni-planar KT-connections to compute the SCFs in multi-planar DKT-joints will lead to either considerably under-predicting or over-predicting results. Hence, it is necessary to develop SCF formulae specially designed for multi-planar DKT-joints. Good results of equation assessment according to UK DoE acceptance criteria, high values of correlation coefficients, and the satisfactory agreement between the predictions of the proposed equations and the experimental data guarantee the accuracy of the equations. Therefore, the developed equations can be reliably used for fatigue design of offshore structures. 展开更多
关键词 offshore jacket structure multi-planar tubular DKT-joint fatigue hot-spot stress method stressconcentration factor (SCF)
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Application of the multi-planar reconstruction in endovascular treatment of type B aortic dissection 被引量:1
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作者 LI Yong-sheng HOU Kai +6 位作者 XU Xin YANG Jue ZHU Ting DONG Zhi-hui YUE Jia-ning WANG Yu—qi FU Wei-guo 《Chinese Medical Journal》 SCIE CAS CSCD 2013年第23期4499-4503,共5页
Background Although Multi-planar reconstruction (MPR) has been considered a diagnostic imaging technique that observes more perspectives for diseases,few people have applied it surgically.In fact,MPR is also very us... Background Although Multi-planar reconstruction (MPR) has been considered a diagnostic imaging technique that observes more perspectives for diseases,few people have applied it surgically.In fact,MPR is also very useful to clinical operation,especially for patients with type B aortic dissection.It helps the surgeon to locate accurately with more information about aortic dissection,so that the safety and effectiveness of operation can be improved.This study examined the application of the MPR in intraoperative DSA imaging for precise positioning by accurately obtaining a crosssection,a spin angle of the coronal plane,and a tilt angle of the sagittal plane in treatment of type B aortic dissection.Methods The conventional and the MPR approaches were compared on positioning the aortic arch for surgery.A group of 40 patients (group A) and another group of 42 patients (group B) was sampled.About the comparison of baseline characteristics,a fourfold table X2 test was conducted on gender,and two independent samples t-test was applied to age between group A and group B.Spin as well as tilt angles for group A were obtained from the patients using both approaches,and their effectiveness was compared with pair t-tests; The MPR data guided stent-grafting in this group.Stent graft placement of group B was based on the conventional approach.Percentages of proximal distributed markers as well as incidences of complications were collected from both groups after stent graft placement.They were also compared with a fourfold table X2 test.Results Gender difference was not found between group A and group B (X2=0.80,P >0.05),and age difference was not statistically significant (F=2.55,homogeneity of variance,t=-1.46,P >0.05).A significant difference was found between the conventional and the MPR approaches for spin angle (t=9.17) as well as tilt angle (t=-2.07),P <0.05.Percentage of proximal distributed markers (5.0%) of group A was significantly lower than that of group B (42.9%),X2=15.92,P <0.05;and incidence of complications (5.0%) of group A was also significant lower than that of group B (21.4%),X2=4.76,P <0.05.Conclusions Application of the MPR facilitated intraoperative angle adaption and led to satisfactory DSA.It is feasible in endovascular treatment of type B aortic dissection,and can effectively and safely guide surgical operations. 展开更多
关键词 multi-planar reconstruction thoracic endovascular aortic repair spin angle tilt angle
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