64层螺旋CT血管成像诊断脊髓血管畸形的价值

目的 探讨64层螺旋CT 血管成像(CTA)对脊髓血管畸形的诊断价值.方法 经临床和MR检查拟诊为脊髓血管畸形的15例患者进行了CTA.所有患者均在1周内进行了DSA检查.其中4例行于术治疗.将CTA图像与DSA和手术所见进行对照,从判定畸形的类型、显示病变累及的范围、供血动脉、引流静脉和可能存在的瘘口等方面,对CTA图像进行评价.结果 15例脊髓血管畸形经DSA和手术确诊,分别为6例髓内动静脉畸彤、2例髓周动静脉瘘、3例硬脊膜动静脉瘘和4例Cobb综合征.CTA对15例患者的分类和对病变累及范围的判断与DSA结果一致.CTA清晰显示了病变的主要供血动脉和引流静脉.5例动静脉瘘中4例CTA判断的瘘口位置与DSA所见一敛,另1例为复杂血管畸形,瘘口难以辨别.CTA还清晰显示了4例Cobb综合征位于椎旁和皮下的畸形血管团.结论 64层螺旋CTA可以判定脊髓血管畸形的类型,快速、无创地显示其主要病变特征,可作为该病的筛查手段.     

64层螺旋CT对下肢动脉疾病的诊断及其临床价值

目的 探讨64层螺旋CT对下肢动脉狭窄闭塞性疾病的诊断价值. 资料与方法 对40例下肢动脉闭塞性疾病患者行64层CT容积扫描,15例1周内同时行数字减影血管造影（DSA）.将下肢血管分成8段,每段血管的狭窄程度被分为：正常、轻度狭窄、中度狭窄、重度狭窄、闭塞5个级别.将DSA与CTA结果进行比较. 结果 共对198个动脉段进行研究,对其狭窄程度显示一致的有191个,被CTA高估6个,低估1个.一致性检验Kappa值为0.953,P=0.017＜0.05,两者分析结果的一致性较好. 结论 64层螺旋CTA是下肢动脉狭窄硬化性疾病的可靠评估方法.     

多层螺旋CT脊髓血管成像的初步研究

目的 探讨多层螺旋CT血管成像（CTA）在脊髓血管病变诊断中的价值。方法 对MRI及临床表现符合脊髓血管病的10例患者行CTA。其中7例于1周内行DSA检查，4例行手术治疗。CT扫描采用Toshiba Aquilion 64层CT扫描机，采用多平面重组、曲面重组、最大密度投影、容积重组方法进行图像后处理。主要从分型、显示病变范围、供血动脉、瘘口及引流静脉等方面对CTA图像进行评价，并与DSA及手术结果对照。结果10例患者CTA均显示了脊髓血管畸形；3例为髓内动静脉畸形，2例为髓周动静脉瘘，5例为硬脊膜动静脉瘘。所有病例均清楚显示病变范围及引流静脉，除1例患者有2根血管为假阳性，其余患者均清楚显示供血动脉并与DSA检查结果一致。结论 CTA对脊髓血管病变的诊断有较大价值，可作为DSA检查前的筛选检查。     

64层螺旋CT头颈联合CTA扫描参数与对比剂剂量最佳匹配选择

目的 探讨64层螺旋CT头颈联合动脉成像时扫描参数和对比剂剂量的最佳匹配方案. 资料与方法 对60例无头颈部动脉系统疾病的志愿者按扫描参数和对比剂剂量的不同随机分为A(螺距1.109,球管旋转时间0.5 s,触发点设在肺动脉主干,对比剂剂量40 ml) 、B(螺距0.891,球管旋转时间0.75 s,触发点设在主动脉弓降部,对比剂剂量70 ml)两组,比较两组的成像质量. 结果 A组显示双侧颈总动脉起始段和椎动脉起始段优于B组(P<0.05),而显示双侧颈总动脉分叉段、颅内动脉及其分支、椎动脉中段两组无差异(P>0.05), A组对防止颅内静脉的过度显影优于B组. 结论 64层螺旋CT头颈联合扫描CTA选择合适的参数对获得较好的图像是非常重要的.     

64层螺旋CT数字减影术对头颈部动脉成像应用研究

目的:探讨64层螺旋CT数字减影技术对头颈部动脉成像的优势。方法:对25例怀疑头颈部血管病变患者行64层螺旋CT血管减影成像检查,用特殊头部固定装置固定头颅,先行平扫,然后以相同的扫描参数行增强扫描,将增强前后图像送至工作站进行减影,利用inspace从减影的图像中提取动脉,进行血管重组,其中15例同时行常规CTA检查,8例行DSA检查,比较减影CTA与常规CTA的成像速度、图像质量,并与DSA成像比较。结果:25例均能显示颈总动脉、颈内动脉、椎动脉及主要分支,其中17例颈椎及颅底骨质完全减去,血管显示良好,8例因检查时头部轻微动或做吞咽动作而造成部分颈椎骨及颅底骨未完全减去,但动脉仍能显示,减影CTA平均成像时间4.3min,常规CTA平均成像时间24.3min,2种成像技术比较,颈部动脉图像质量无明显差别,减影CTA对颅内动脉主干及更多分支的显示优于常规CTA,减影CTA与8例DSA比较图像完全相同。结论:64层螺旋CT血管减影技术省时省力、便捷灵活、图像质量好,值得在临床推广。     

64层螺旋CT动脉成像的临床应用

目的 探讨多层螺旋CT血管造影在动脉血管方面的应用价值.方法 回顾性分析用64层螺旋CT血管造影检查165例患者的影像资料.结果 28例头颈部CTA发现动脉粥样硬化狭窄及阻塞14例,动脉瘤5例,动静脉瘘1例,大动脉炎1例,肿瘤压迫1例;38例肺动脉CTA发现肺动脉栓塞21例;32例主动脉CTA发现动脉粥样硬化14例,主动脉夹层8例,动脉瘤1例,大动脉炎1例,动静脉瘘1例;40例肾动脉CTA发现4例血管变异(副肾动脉),狭窄15例,先天性变细3例,血肿压迫1例;27例四肢动脉CTA发现动脉硬化6例,动脉损伤9例,外伤后动静脉瘘及动脉狭窄各1例,肿瘤致血管受压3例.结论 多层螺旋CT血管造影对全身各部位动脉病变诊断有重要的临床应用价值.     

256层CT血管成像对冠状动脉瘘的诊断价值

目的 探讨256层CT血管成像(CTA)对冠状动脉瘘(CAF)的诊断价值.方法 回顾性分析CAF 18例,对原始图像进行多平面重组(MPR)、曲面重组(CPR)、最大密度投影(MIP)及容积重建(VR)等后处理.结果 18例CAF中冠状动脉分支血管瘘入肺动脉5例;瘘入冠状静脉窦5例;瘘入右心房3例;瘘入左心房3例;瘘入右心室2例.5例冠状动脉 -肺动脉瘘可观察到畸形血管向肺动脉内供血,肺动脉主干内均可见对比剂呈"喷射"或"浓染"征.主肺动脉旁形成丛状或蔓藤状血管网2例.供血动脉区动脉瘤形成3例.结论 256层冠状动脉CTA能准确显示CAF变异血管的解剖细节及血流动力学改变情况,运用多种重建技术能够直观地显示CAF的畸形血管形态.     

256层CT心电前置门控及回顾门控冠状动脉成像质量及辐射剂量比较

目的 比较256层CT前置门控冠状动脉CTA与回顾门控检查方法的成像质量及辐射剂量,探讨256层CT前置门控冠状动脉扫描方法的临床应用价值及局限性.方法 回顾分析177例冠状动脉256层CTA检查患者,其中前置门控86例,回顾门控91例.将冠状动脉主要分支分为9个节段评价,采用4分法评价图像质量,≥3分为可评价节段.采用t检验比较两种方法组可评价节段的百分比、患者的有效辐射剂量及图像噪声.结果 前置门控组86例中98.8%节段(765/774)为可评价节段.回顾门控组91例中99.6%节段(816/819)可评价.2组图像质量差异有统计学意义(t=2.51,P=0.01).心率<75次/min时,前置门控与回顾门控组的可评价节段分别为99.8%(647/648),99.7%(718/720),图像质量的差异无统计学意义(t=1.90,P>0.05).≥75次/min时,2组的可评价节段分别为93.6%(118/126)和99.0%(98/99).2组的可评价率差异有统计学意义(t=3.57,P<0.05).前置门控组及回顾门控组的有效辐射剂量分别为(4.4±0.5)和(10.3±1.5)mSv(t=33.4,P<0.00),前置门控扫描的剂量明显小于回顾门控扫描,下降幅度达60.0%.结论 256层CT前置门控冠状动脉扫描方法较回顾门控方法剂量显著降低,两种扫描方法得到的图像质量均较好.在低心率组图像质量两种方法相近,而高心率组前置门控较回顾门控法有差距.     

64层螺旋CT对冠状动脉粥样硬化血管狭窄的评价

目的:探讨64层螺旋CT对冠状动脉粥样硬化各种程度血管狭窄的评估价值.方法:120例患者行64层螺旋CT血管造影(CTA)检查评价冠状动脉各段的狭窄程度,并与冠状动脉血管造影(CAG)比较,统计64层螺旋CTA诊断冠状动脉各种程度狭窄的敏感性、特异性、阳性预测值(PPV)和阴性预测值(NPV).结果:64层螺旋CTA评...     

64排螺旋CT对冠状动脉瘘的诊断价值

目的:探讨64排螺旋CT对冠状动脉瘘的诊断价值。方法:回顾性分析经造影或手术证实的6例冠状动脉瘘患者的64排螺旋CT表现,由两名放射科医师独立评价64排螺旋CT图像的质量和诊断准确性。结果:6例冠状动脉CTA图像可供评价,与术中所见和选择性动脉造影吻合。6例冠状动脉瘘中,2例冠状动脉-肺动脉瘘,3例冠状动脉-右室瘘,1例冠状动脉-左房瘘,6例均作出正确诊断。3例冠状动脉-右室瘘合并右冠状动脉扩张,射血分数(EF)为50%～72%,其余3例EF为65%～71%。结论:64排螺旋CT能比较全面显示冠状动脉异常血管、瘘口以及评估心功能,是诊断冠状动脉瘘的可靠方法。     

Enhancement performance of a 64-slice triple rule-out protocol vs 16-slice and 10-slice multidetector CT-angiography protocols for evaluation of aortic and pulmonary vasculature

OBJECTIVE: To compare the enhancement of the pulmonary and aortic vasculature between a biphasic injection 64-slice, a single-phase injection 16-slice, and a single-phase injection 10-slice multidetector computed tomographic (CT) angiography (CTA) protocols. METHODS: With institutional review board approval and Health Insurance Portability and Accountability Act compliance, 50 patients (16 men, 34 women; mean age, 51.5 years; range, 30-75 years) with atypical chest pain from the emergency department were scanned using a triple rule-out protocol on a 64-slice CT scanner. Pulmonary enhancement was compared with 50 patients (21 men, 29 women; mean age, 65.6 years; range, 38-90 years) imaged with a single-phase 16-slice pulmonary angiography protocol. Aortic enhancement was compared with 24 patients (12 men, 12 women; mean age, 66.1; range, 34-92 years) who were imaged with a 16-slice aortic dissection CTA protocol and to 25 patients (15 men, 10 women; mean age, 50.8 years; range, 20-83 years) imaged with a 10-slice aortic dissection CTA protocol. A 2-tailed Student t test or sign test was used to assess significant differences from a vascular attenuation cutoff value of 250 Hounsfield units (HU). RESULTS: Individual mean pulmonary arterial and aortic attenuation values were statistically significantly less than 250 HU for the 16- and 10-slice protocols and statistically significantly more than 250 HU for the 64-slice protocols (P < 0.05). Mean pooled pulmonary attenuation values were more than 250 HU in 18% (9/50) of the 16-slice and in 93% (39/42) of the 64-slice protocols. Mean pooled aortic attenuation values were more than 250 HU in 18.4% (9/49) of the 10- and 16- and in 100% (42/42) of the 64-slice protocols. CONCLUSIONS: The triple rule-out 64-slice biphasic injection breath hold CTA protocol provides significantly higher attenuation of aortic and pulmonary vasculature compared with our current 10- and 16-slice protocols.     

Clinical application of 64-slice spiral CT in the diagnosis of the Tetralogy of Fallot

OBJECTIVE: To explore the clinical application of 64-slice spiral CT in the diagnosis of the Tetralogy of Fallot. METHODS: Eighteen patients with diagnosed Tetralogy of Fallot underwent cardiac CT angiography with 64-slice CT (CTA). Two- and three-dimensional images were used for diagnosing in all cases by means of MPR (coronal, sagital and oblique), cMPR, MIP and VRT. RESULTS: All patients had ventricular septal defect, pulmonary stenosis and hypertrophy of right ventricle. The morphologic features of Tetralogy of Fallot were equal to echocardiography. Patent ductus arteriosus (PDA) were detected on eight patients. Main coronary artery branches and partial sub-branches were visualized in all patients. Abnormal coronary arteries were found in seven cases: both left and right main coronary artery arising from the right aortic sinus one case, right main coronary artery and circumflex (CX) arising from the right aortic sinus one case, left anterior descending (LAD) and CX arising from left aortic sinus directly one case, left and right coronary artery arising from back and front of the aortic sinus, respectively, three cases. Pulmonary artery branch stenosis was found in 12 cases and branch pulmonary artery dilation noticed in 1 case. Double superior vena cava was also found in one case. According to the surgery the diagnostic accuracy of CT and Echocardiography was 95.45 and 83.33%, respectively. CONCLUSION: Two- and three-dimensional 64-slice CTA not only show the overall anatomical structure of the heart, but also show coronary and pulmonary arteries. With these results, evaluation of coronary anomalies and pulmonary artery stenosis with 64-MSCT is extremely valuable for planning the operative procedure on the patients with Tetralogy of Fallot.     

低剂量容积CT灌注成像CTA对宫颈癌供血血管的显示效果分析

目的探讨基于盆腔容积CT灌注成像的CTA图像对宫颈癌供血血管的显示价值。方法选取我院86例宫颈癌患者随机分为A、B两组,每组43例。A组行盆腔容积CT灌注扫描,获得髂外动脉的时间密度曲线(TDC),确定髂外动脉达峰时间(TTP),以TTP时相原始图像重建三维CTA图像。B组行数字减影血管造影术(Digital subtraction angiography,DSA)获得血管图像。以DSA图像为金标准,分析低剂量容积CT灌注成像的CTA对宫颈癌供血血管的显示效果。采用Kappa检验,评估两名影像医师分析双侧子宫动脉主干的起源及连续性显示的一致性,同时将卡方检验用于评估两者判定子宫动脉下行分支显示率的差异。结果两名医师对A、B组图像的评分一致性良好(A组Kappa=0.899,P<0.001,B组Kappa=0.782,P<0.001);A、B两组对双侧子宫动脉主干血管的显示情况无统计学差异(甲医师χ^2=0.213,P>0.05;乙医师χ^2=0.343,P>0.05);甲医师对A组B组子宫动脉下行支的显影率分别为97.7%(42/43)和100%(43/43),乙医师对A组B组子宫动脉下行支的显影率分别为95.3%(41/43)和97.7%(42/43)。两名医师对A、B组子宫动脉下行支显影率的评价一致性良好,(A组Kappa=0.656,P<0.001;B组Kappa=0.306,P<0.001);两名医师判定的CTA图像及DSA图像对子宫动脉下行支显影率无统计学差异(甲医师χ^2=1.01,P>0.05;乙医师χ^2=0.345,P>0.05)。结论以DSA图像为标准,基于容积CT灌注成像的CTA可良好地显示宫颈癌供血血管,对双侧子宫动脉主干的起源及连续性和对子宫动脉下行支的显示具有很好稳定性。     

采用256层CT全脑灌注研究烟雾病术后桥血管再通及手术前后脑血流动力学的变化

目的 研究256层CT全脑灌注同时评价烟雾病术后桥血管再通及手术前后脑血流动力学变化的可行性.方法 选取25例烟雾病患者在手术前后均行全脑CTP检查.容积CTA图像通过CTP动脉期原始图像获得,并与术后的常规CTA图像进行比较.测量患者手术侧及对侧的大脑中动脉分布区的灌注参数,包括脑血流量(CBF)、脑血容量(CBV)、平均通过时间(MMT)和达峰时间(TTP),计算术侧/对侧相对比值(rCBF、rCBV、rTTP及rMTT值).采用配对t检验或配对秩符号检验比较手术前后CT灌注参数值及相对值的差异.正态分布数据以x±s表示,非正态分布数据以M(P25～P75)表示.结果 25例患者术后桥血管均显示通畅.容积CTA图像与传统CTA图像显示桥血管情况的结果一致.烟雾病患者血管搭桥术后手术侧大脑中动脉分布区的CBF[72.86(55.54～112.19)ml·100g-1·min-1]、rCBF[1.31(1.05～1.73)]及rCBV(1.45±0.62)明显高于术前的CBF[46.72(28.57～57.67)ml·100g-1·min-1]、rCBF[0.53(0.33～0.82)]及rCBV(1.01±0.36)(Z值分别为-2.72、-2.98,t=-2.85,P值均＜0.05);术后患侧大脑中动脉分布区的MTT[(3.98±2.36)s]、TTP[(17.56±4.38)s]及rTTP(1.01±0.09)明显低于术前的MTT[(5.43±2.07)s]、TTP[(19.40±3.87)s]及rTTP(1.14±0.28)(t值分别为2.41、2.17、2.17,P值均＜0.05).结论 256层CT经单次注射对比剂、单次扫描可同时获得CTA图像及全脑CTP参数图,可对烟雾病术后桥血管再通情况及脑血流动力学变化同时进行评价.     

High-resolution ex vivo imaging of coronary artery stents using 64-slice computed tomography—initial experience

The aim of the study was to evaluate the potential of new-generation multi-slice computed tomography (CT) scanner technology for the delineation of coronary artery stents in an ex vivo setting. Nine stents of various diameters (seven stents 3 mm, two stents 2.5 mm) were implanted into the coronary arteries of ex vivo porcine hearts and filled with a mixture of an iodine-containing contrast agent. Specimens were scanned with a 16-slice CT (16SCT) machine; (Somatom Sensation 16, Siemens Medical Solutions), slice thickness 0.75 mm, and a 64-slice CT (64SCT, Somatom Sensation 64), slice-thickness 0.6 mm. Stent diameters as well as contrast densities were measured, on both the 16SCT and 64SCT images. No significant differences of CT densities were observed between the 16SCT and 64SCT images outside the stent lumen: 265±25HU and 254±16HU (P=0.33), respectively. CT densities derived from the 64SCT images and 16SCT images within the stent lumen were 367±36HU versus 402±28HU, P<0.05, respectively. Inner and outer stent diameters as measured from 16SCT and 64SCT images were 2.68±0.08 mm versus 2.81±0.07 mm and 3.29±0.06 mm versus 3.18±0.07 mm (P<0.05), respectively. The new 64SCT scanner proved to be superior in the ex vivo assessment of coronary artery stents to the conventional 16SCT machine. Increased spatial resolution allows for improved assessment of the coronary artery stent lumen.     

256层螺旋CT前瞻性心电门控冠状动脉成像应用高心率患者临床分析

目的：探讨心率＜100bpm稳定窦性心率患者256层螺旋CT于收缩末期（40％～50％位相）应用前瞻性心电门控冠状动脉成像的可行性。方法回顾分析271例患者256层螺旋C T回顾性心电门控冠状动脉成像收缩末期（40％～50％位相）图像,所有病例按70bpm≤心率＜80bpm ,80bpm≤心率＜90bpm ,90bpm≤心率＜100bpm分成3组,对所有冠状动脉节段图像质量进行评分（4分法）,比较不同心率组间的图像质量。结果271例患者共重建3780个冠状动脉节段,可评估者3708个节段,三组冠状动脉可评价率分别为98．59％、97．79％、97．9％,组间两两比较差异均无统计学意义。结论心率＜100bpm稳定窦性心率患者256层螺旋CT冠状动脉成像于收缩末期（40％～50％位相）可获得稳定的满足诊断的图像,应用前瞻性心电门控技术成功把握大。     

Noninvasive gadolinium-enhanced three dimensional computed tomography coronary angiography

RATIONALE AND OBJECTIVES: Although the use of gadolinium (Gd)-based contrast agents for angiographic studies of abdominal aorta, renal vasculature, and digital subtraction angiography has been reported, no studies have shown their diagnostic efficacy and image quality in coronary computed tomography angiography (CTA). The aim of this study is to evaluate the image quality of Gd-based contrast agents during coronary CTA. MATERIALS AND METHODS: A phantom study was done to evaluate the attenuation of serial dilutions of Gd and iodinated agents. This study was done on a 64-slice multirow detector CT (MDCT) scanner and e-speed scanner and CT attenuation Hounsfield units (CTHU) were compared. We evaluated 35 consecutive patients who underwent Gd-enhanced CTA. CTHU of aorta was measured at first, mid, and lowest slice levels with and without contrast administration. The image quality was graded on the basis of visualization of the coronary arteries (scale I-III; III demonstrating diagnostic image quality of the distal-most vessels). In a substudy, four patients with borderline renal insufficiency underwent CTA using Gd and iodinated contrast agents admixed in a 50:50 ratio. RESULTS: The phantom study showed that enhancement of various dilutions of Gd and iodine resulted in near identical CTHU with both e-speed and 64-slice scanners (r(2) > or = 0.997). Mean CTHU with contrast at the top slice was 116 HU, at middle slice was 125 HU, and at the lower slice was 93 (111.14 +/- 22). Quality evaluation showed 2 grade III, 9 grade II, and 24 grade I images (average quality of images 1.35). Mean CTHU was 222. CONCLUSION: Gd-enhanced contrast medium provides adequate enhancement of coronary vasculature, allowing for diagnostic evaluation of coronary arteries with new CT systems. Use of newer generations of multirow detector CT scanners should further enhance the quality of images.     

Identification of the normal appendix in healthy adults by 64-slice MDCT: the value of adding coronal reformation images

The aim of this study was to assess retrospectively the value of adding coronal reformation images to the identification of the normal appendix using 64-slice multidetector CT (MDCT). 200 consecutive healthy adults with no history of abdominal surgery underwent abdominal CT using 64-slice MDCT without oral contrast administration and were enrolled in the study. Two gastrointestinal radiologists first interpreted the axial images only; after a 2-week interval, they then interpreted both the axial and the coronal images while blinded to the first interpretation. The identification of the normal appendix was interpreted using a four-point scale: 1, not identified; 2, identified with low confidence; 3, probably identified; 4, definitely identified. Agreement between the readers was determined with the use of weighted kappa statistics. Differences in confidence ratings for identification of the appendix were determined with the Wilcoxon signed rank test. The agreement between the readers was higher when both axial and coronal images were reviewed (kappa = 0.85) than when only the axial scans images were reviewed (kappa = 0.43). The mean confidence scores for the identification of the normal appendix by the two readers were significantly higher when both the axial and coronal images were reviewed (mean, 3.81+/-0.498 and 3.83+/-0.485 for the two readers, respectively) than when only the axial images were reviewed (mean, 3.27+/-0.819 and 3.47+/-0.856, respectively) (all p<0.01). Therefore, adding coronal reformation images to 64-slice MDCT significantly improves inter-reader agreement and confidence in the identification of the normal appendix.     

含服硝酸甘油对64层螺旋CT冠状动脉成像质量影响的分析

目的 定量评估64层CT在冠状动脉成像中含服和不含服硝酸甘油对冠状动脉显示的差异.方法 分别在相对时段中对含服硝酸甘油(A组)和不含服硝酸甘油(B组)的各100例患者进行64层CT冠状动脉检查,2组受检者均采用回顾性后门控智能mA扫描技术.分别选取左、右冠状动脉的最佳期相进行MPR、MIP、CPR、VR重组.对2组图像分别进行冠状动脉10个测量点管径的测量,并对右冠状动脉、前降支、回旋支3支冠状动脉显示的分支数目进行统计,然后对2组图像管径测量值和分支数目采用完全随机的两样本均数t检验进行统计学比较.结果 右冠状动脉近、中、远段管径A组比B组分别增加0.29、0.17、0.11mm,扩张率分别为8.0%、5.0%、4.0%;前降支分别增加0.40、0.23、0.10 mm,扩张率分别为11.0%、8.0%、4.7%;回旋支分别增加0.42、0.35、0.12 mm,扩张率分别为13.5%、12.5%、5.5%;左主干增加0.31 mm,扩张率7.8%.A组较B组分支数目增加率,右冠状动脉、前降支、回旋支分别为83%、80%、113%.A、B 2组冠状动脉10个血管节段中,右冠状动脉近段、左主干、前降支近、中段、回旋支近、中段差异有统计学意义(t值分别为3.86、3.74、5.35、3.58、5.29、4.64,P值均＜0.01);右冠状动脉中、远段、前降支远段、回旋支远段差异亦有统计学意义(t值分别为2.13、2.58、2.35、2.14,P值均＜0.05).结论 服用硝酸甘油能有效扩张冠状动脉并能有效增加冠状动脉分支的显示,从而提高64层CT冠状动脉成像质量.