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1.
目的:研究CT值评价局部晚期胃癌病人胃的血供在临床的应用价值。方法:从2013年9月起对我院收治的局部晚期胃癌病人进行研究。通过CT检查胃癌与邻近重要脏器、血管的关系,可切除者行胃癌根治术,不能切除者先行术前化疗,再手术治疗。计算门静脉期和平扫期肿瘤的CT值,并以同层主动脉的CT值校正,获得主动脉校正CT(aorta adjusted CT, AACT)值。术前化疗病人给予动静脉结合口服化疗,评估化疗反应。结果:至2017年11月,完成300例胃癌病人,其中直接手术179例,接受术前化疗121例。病人年龄为(59.03±10.82)岁,AACT值为0.574 1±0.118 3。不同性别、肿瘤位置及大体类型病人的肿瘤AACT值均无统计学差异(P0.05)。病理组织学类型方面,高中分化腺癌、低分化腺癌以及印戒细胞癌的AACT值在两两之间均有统计学差异(P分别为0.024、0.001、0.030)。术前化疗有效组87例,AACT值为0.628 6±0.192 2,化疗无效组34例,AACT值为0.494 5±0.245 1,两组AACT值有显著统计学差异(P0.001)。术前化疗对富血供的肿瘤具有较好的疗效。AACT阈值为0.516 4,其灵敏度和特异度分别为80.5%和67.6%。受试者工作特征曲线下面积为0.758。结论:分化程度高的胃癌血供好。AACT高水平下局部不能切除的胃癌病人肿瘤血供可能更丰富,术前化疗效果好,获得手术机会。 相似文献
2.
Objective To assess the clinical value of dual-energy intracranial CT angiography (CTA).Methods Forty-one patients suspected of intracranial vascular diseases underwent dual-energy intracranial CT angiography, and 41 patients who underwent conventional subtraction CT were enrolled as the control group.Image quality of intracranial and skull base vessels and radiation dose between dual-energy CTA and conventional subtraction CTA were compared using two independent sample nonparametrie test and independent-samples t test, respectively.Prevalence and size of lesions detected by dual-energy CTA and digital subtraction CTA were compared using paired-samples t test and Spearman correlative analysis. Results The percentage of image quality scored 5 was 70.7% (29/41) for dual-energy CTA and 75.6% (31/41) for conventional subtraction CTA.There was no significant difference between the two groups(Z= -0.455, P=0.650).Image quality of vessels at the skull base in conventional subtraction CTA was superior to that in dual-energy CTA, especially for the petrosal and syphon segment (Z=-4.087, P= 0.000).Radiation exposure of dual energy CTA and conventional CTA were (396.54±17.43) and (1090.95±114.29) mGy · cm respectively.Radiation exposure was decreased by 64% (t=-38.52, P=0.000) by dual energy CTA compared with conventional subtraction CTA.Out of the 41 patients,19 patients were diagnosed as intracranial aneurysm, 2 patients as arteriovenous malformation (AVM), 3 patients with Moya-moya's disease, and the remaining 17 patients with negative results.Nine patients with intracranial aneurysm, 2 patients with AVM, 3 patients with Moya-moya's disease, and 2 patients with negative findings underwent DSA or operation, with concordant findings from both techniques.Diameter of aneurysm neck, long axis and minor axis by dual-energy CTA was (2.90±1.61), (5.23±1.68) and (3.83±1.69) nun, respectively; Diameter of aneurysm neck, long axis and minor axis by DSA was (2.95±1.71), (5.10±1.60) ,(3.83±1.65) nan,respectively.There was no significant difference for the diameters of aneurysm between dual energy CTA and DSA ((t=-0.734,1.936,0.12.5 respectively, P=0.482,0.085,0.903 respectively), and good correlation was found between diameter measurements using the two techniques(r=0.964,0.976,0.973, respectively, all P=0.000) Conclusions Compared with conventional subtraction CTA, dual energy CTA has good image quality for intracranial vessels; however, image quality of the skull base vessels is worse, especially for the petrosal and syphon segment.Dual energy CTA has decreased radiation dose and a high diagnostic accuracy, being a practical imaging madality for diagnosis of intracranial vascular lesions. 相似文献
3.
不同心率水平下双源CT冠状动脉成像质量研究 总被引:3,自引:0,他引:3
目的:研究不同心率状态下双源CT的冠状动脉成像质量情况及收缩期和舒张期成像质量的差异。方法:345例受试者,男248例,女97例,年龄24~86岁,心率49~133次/分,平均心率74.2±14.4次/分(均未给予药物控制心率),行双源CT冠状动脉CTA扫描,在后处理工作站进行三维重组后,由两名有经验的放射医师对所有受检对象的冠状动脉成像质量进行分段评分(1分~5分)。按受检时心率分为5组,分别统计各组冠状动脉各段的成像质量评分,收缩期和舒张期最佳时相的成像质量评分,以及最佳时相在R-R间期的分布情况。结果:成像成功率为99.9%(3392/3395)。图像质量评分总均值为(4.76±0.57),评分均值与心率呈负相关(r=-0.973,P=0.005)。当心率增高时,收缩期的成像质量和舒张期的成像质量均有下降的趋势,但收缩期下降幅度与舒张期比较明显较缓。当心率<80次/分时,最佳时相多数在舒张期得到,占79.6%(183/230),特别集中于R-R间期的70%左右,占68.3%(157/230),有88.7%(306/345)的受检对象在收缩期和舒张期两期都能得到优良(4分以上)的图像;当心率≥80次/分时,最佳时相多数在收缩期得到,占83.5%(96/115),仅有10.4%(12/345)的受检对象在收缩期和舒张期两期都能得到优良的图像。结论:在排除了心律不齐影响因素的情况下,双源CT在患者处于自然心率状态下其冠状动脉成像成功率接近100%;但心率对冠状动脉成像质量仍有一定影响;当心率<80次/分时大多数可以在收缩期和舒张期双期成像,而心率≥80次/分时一般只能在收缩期成像。 相似文献
4.
多层螺旋CT对肺栓塞影像表现及与其严重性关系的评价 总被引:2,自引:0,他引:2
目的 评价多层螺旋CT肺栓塞影像表现及与其严重性的关系.资料与方法 回顾性分析104例临床诊断肺栓塞患者的临床及影像学资料,测量心血管参数:主肺动脉直径、右心室短轴最大径(RVMSA)、左心室短轴最大径(LVMSA)及RVMSA/LVMSA比值,计算CT肺动脉成像(CTPA)阻塞指数,评价CTPA上栓子的形态和与双能量CT(DECT)上灌注缺损的关系及CTPA阻塞指数与心血管测量参数的关系.结果 104例中,32例因图像丢失(n=10)、CTPA图像欠佳,不满足测量要求(n=9)或未行CTPA检查(n=13),故只对72例患者的影像学资料进行分析评价.完全闭塞型肺栓塞DECT表现为整个肺叶灌注降低或某个肺段灌注缺损,部分闭塞型DECT表现为灌注降低或正常.CT阻塞指数与心血管测量参数具有一定的相关性(P<0.05),以CT阻塞指数与RVMSA/LVMSA比值相关性最高(r=0.519,P<0.001).结论 肺灌注异常与否取决于肺动脉栓塞的程度;CT肺动脉阻塞指数可用于评价肺栓塞的严重性. 相似文献
5.
【摘要】目的:探讨双能量CT电子云密度/等效原子系数(Rho/Z)鉴别小肾癌(1~4cm)中肾透明细胞癌(ccRCC)和非透明细胞癌(nccRCC)的价值。方法:回顾性收集2012年1月-2016年10月行术前双能量CT增强扫描的87例肾细胞癌患者,其中ccRCC 70例,nccRCC 17例。选取增强扫描皮髓质期图像,并应用双能量CT Rho/Z对所有图像进行评估,记录Z、Rho和双能量指数(DEI)值。比较Z、Rho和DEI值在ccRCC和nccRCC组间的差异,采用受试者工作特征(ROC)曲线分析各参数的鉴别诊断效能。结果:Z和DEI在ccRCC和nccRCC组间均具有统计学差异(P均<0.001)。在ccRCC和nccRCC的鉴别诊断中,Z的最佳诊断阈值为9.69,总体正确率为88.5%,敏感度为94.1%,特异度为87.1%,ROC曲线下面积(AUC)为0.955;DEI的最佳诊断阈值为0.044,总体正确率为83.9%,敏感度为100%,特异度为80%,AUC为0.953。结论:在增强扫描皮髓质期中,双能量CT的Rho/Z应用中的参数有助于小肾癌(1~4cm)中ccRCC和nccRCC的鉴别。 相似文献
6.
Objective To assess the clinical value of dual-energy intracranial CT angiography (CTA).Methods Forty-one patients suspected of intracranial vascular diseases underwent dual-energy intracranial CT angiography, and 41 patients who underwent conventional subtraction CT were enrolled as the control group.Image quality of intracranial and skull base vessels and radiation dose between dual-energy CTA and conventional subtraction CTA were compared using two independent sample nonparametrie test and independent-samples t test, respectively.Prevalence and size of lesions detected by dual-energy CTA and digital subtraction CTA were compared using paired-samples t test and Spearman correlative analysis. Results The percentage of image quality scored 5 was 70.7% (29/41) for dual-energy CTA and 75.6% (31/41) for conventional subtraction CTA.There was no significant difference between the two groups(Z= -0.455, P=0.650).Image quality of vessels at the skull base in conventional subtraction CTA was superior to that in dual-energy CTA, especially for the petrosal and syphon segment (Z=-4.087, P= 0.000).Radiation exposure of dual energy CTA and conventional CTA were (396.54±17.43) and (1090.95±114.29) mGy · cm respectively.Radiation exposure was decreased by 64% (t=-38.52, P=0.000) by dual energy CTA compared with conventional subtraction CTA.Out of the 41 patients,19 patients were diagnosed as intracranial aneurysm, 2 patients as arteriovenous malformation (AVM), 3 patients with Moya-moya's disease, and the remaining 17 patients with negative results.Nine patients with intracranial aneurysm, 2 patients with AVM, 3 patients with Moya-moya's disease, and 2 patients with negative findings underwent DSA or operation, with concordant findings from both techniques.Diameter of aneurysm neck, long axis and minor axis by dual-energy CTA was (2.90±1.61), (5.23±1.68) and (3.83±1.69) nun, respectively; Diameter of aneurysm neck, long axis and minor axis by DSA was (2.95±1.71), (5.10±1.60) ,(3.83±1.65) nan,respectively.There was no significant difference for the diameters of aneurysm between dual energy CTA and DSA ((t=-0.734,1.936,0.12.5 respectively, P=0.482,0.085,0.903 respectively), and good correlation was found between diameter measurements using the two techniques(r=0.964,0.976,0.973, respectively, all P=0.000) Conclusions Compared with conventional subtraction CTA, dual energy CTA has good image quality for intracranial vessels; however, image quality of the skull base vessels is worse, especially for the petrosal and syphon segment.Dual energy CTA has decreased radiation dose and a high diagnostic accuracy, being a practical imaging madality for diagnosis of intracranial vascular lesions. 相似文献
7.
8.
目的 CT冠状动脉成像目前已经广泛应用于临床,然而它的高辐射剂量一直受到人们的关注,降低CT冠状动脉检查的辐射剂量有重要的社会意义。文中探讨基于患者BMI调节管电压的前瞻性大螺距CT冠状动脉成像(CT coronary angiography,CTCA)的可行性。方法选取102例患者并行CTCA检查,其中实验组(72例)采用基于BMI调整管电压,BMI<23 kg/m2者选择70 k V,BMI 23~25 kg/m2之间者选择80 k V,BMI>25 kg/m2者行自动管电压选择技术;对照组(30例)采用120 k V前瞻性序列心电门控技术行CTCA。评估并比较2组的主观和客观图像质量及辐射剂量。结果实验组右冠状动脉CT值高于对照组[(562.2±152.3)HU vs(399.6±61.3)HU];实验组左冠状动脉主干CT值高于对照组[(571.1±159.5)HU vs(380.3±46.2)HU];实验组前降支CT值高于对照组[(559.4±140.9)HU vs(356.0±39.7)HU];实验组回旋支的CT值高于对照组[(553.0±168.6)HU vs(348.9±52.3)HU],差异均有统计学意义(P<0.001)。而实验组右冠状动脉、左冠状动脉主干、前降支和回旋支的对比噪音比与对照组比较,差异均无统计学意义(P>0.05)。2组主观图像质量的差异亦无统计学意义(P=0.604)。实验组的有效剂量明显低于对照组[(0.5±0.5)m Sv vs(4.5±1.3)m Sv,P<0.001]。实验组相比于对照组120 k V前瞻性序列扫描CTCA辐射有效剂量降低了88.9%。结论基于患者BMI调节管电压的前瞻性大螺距CTCA具有可行性。 相似文献
9.
目的选择双源CT冠状动脉的最佳重建期相,比较全期相固定间隔重建技术与自动化最佳期相选择技术所选择的最佳冠状动脉影像质量。方法对107例病人进行了双源CT冠状动脉血管成像。原始数据经多期相重建和自动化重建优选出最佳收缩期和舒张期影像,以4分法评定系统进行影像质量评价。按照美国心脏病协会的冠状动脉分段原则进行分段。比较上述2种技术最佳收缩期和舒张期的影像质量。结果最佳的影像质量位于R-R间期的70%(平均评分3.11),次之为R-R间期的75%(平均评分3.06)、再之为35%(平均评分为3.03)。自动化期相选择的最佳收缩期影像的平均评分为3.05,舒张期影像质量的平均评分为3.08。2组之间总的冠状动脉影像质量的差别没有统计学意义。按照15个冠状动脉节段计算,除了4段外,其余14个冠状动脉节段对于2种技术显示的冠状动脉影像质量的差别均无统计学意义。结论最佳舒张期和收缩期的影像质量位于R-R间期的70%和35%。自动化最佳收缩期和舒张期重建技术可以获得优良的影像质量,满足临床诊断的需要,但仍需要结合多期相重组技术。 相似文献
10.
双源CT冠状动脉检查的技术特点及其过程初探 总被引:2,自引:0,他引:2
目的:探讨双源CT冠状动脉检查的原理、步骤及注意事项,归纳总结双源CT冠状动脉检查的技术特点及其一般过程。方法:以2007年度南京军区总院行双源CT冠状动脉检查患者的检查过程为样本,结合南京军区总院关于双源CT冠状动脉成像的各种研究成果,对双源CT冠状动脉检查的技术特点及其一般过程进行总结。结果:双源CT冠状动脉检查的整个流程可分为扫描前准备、扫描、扫描后患者护理及图像后处理4个方面,检查过程中还有一些其他注意事项值得注意。结论:双源CT冠状动脉检查必须遵循一定的检查原则及一些注意事项才能发挥其最大优势。 相似文献