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1.
Ӱ�����ڸ�����Ƶ�Ӧ����״�ͽ�չ 总被引:4,自引:0,他引:4
普外科的发展和医学影像的发展密切相关,影像学在对普通外科的各种疾病的诊断、治疗方案的选择、愈后的评估、肿瘤的可切除分析等方面起着重要作用。随着科学技术的发展,医学影像由普通的X线、超声发展到CT、磁共振等,其检查技术日新月异,包括传统X线照片、胃肠道造影(GI)、内镜逆行胰胆管造影(ERCP)、窦道造影、数字减影血管造影(DSA),常规超声、内镜超声,CT平扫、增强扫描、动脉造影CT增强(CTA)、经门静脉造影CT增强(CTAP),MRI平扫、增强扫描、MRCP,单光子发射计算机断层显像(ECT)、正电子发射断层显像(PET),PET/CT,以及各种影像引导下的穿刺活检和治疗等。这些众多的影像学方法 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.
检测痰脱落细胞p16基因甲基化对周围型肺癌的诊断价值 总被引:4,自引:0,他引:4
目的 探讨检测痰脱落细胞p16基因甲基化对周围型肺癌的诊断价值。方法 应用甲基化特异性PCR(methylation specificPCR ,MSP)对 5 0例周围型肺结节患者及 2 0例正常人痰脱落细胞p16基因甲基化改变进行检测 ,将检测结果与术后病理报告相对照。结果 周围型肺癌痰脱落细胞 p16MSP阳性率( 2 7/ 44 ,61.4%)明显高于良性周围型肺结节 ( 1/ 6,16.7%)及正常人 ( 3 / 2 0 ,15 .0 %) ( χ2 值分别为 4.2 81和11.869,P <0 .0 5 ) ,良性周围型肺结节 p16MSP阳性率与正常人无显著性差异 ( χ2 =0 .13 6,P >0 .0 5 )。鳞癌和腺癌患者痰脱落细胞 p16MSP阳性率无显著性差异 ( χ2 =3 .416,P >0 .0 5 )。如果以痰脱落细胞 p16MSP阳性作为判断肺结节恶性的标准 ,其诊断周围型肺癌的阳性预测值为 96.4%,阴性预测值 2 2 .7%,灵敏度 61.4%,特异度 83 .0 %。结论 检测痰脱落细胞 p16基因甲基化对周围型肺癌具有辅助诊断价值 相似文献
4.
5.
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
6.
内蒙三个地砷病区饮水中形态砷化物水平及其对发病的影响 总被引:6,自引:0,他引:6
内蒙三个地砷病区饮水中形态砷化物水平及其对发病的影响卢光明1戚其平2于文学3郑星泉2姚孝元2史根生4我们在对内蒙地方性砷中毒(endemicarsenism,简称地砷病)病区饮水中形态砷化物水平测定的基础上,进行了形态砷化物水平对地砷病发病影响的人群... 相似文献
7.
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
8.
双源CT及其临床应用 总被引:12,自引:0,他引:12
近年来多层螺旋CT技术的持续进步不仅使冠状动脉的CT成像进入了临床实用阶段,而且在有选择性的患者中有望代替有创性的冠状动脉造影检查.从4层CT到64层CT时间分辨率不断提高的同时,也提高了冠状动脉CT的诊断能力. 相似文献
9.
【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
10.
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