对电子束CT冠状动脉钙化评分准确性的评价

目的：评价在电子束ＣＴ图像上测定冠状动脉钙化准确性。材料和方法：选择两位有经验的医生分别对经ＩｍａｔｒｏｎＣ－１５０电子束ＣＴ机检查的５０例作冠状动脉钙化定性和定量积分测定，其中一位医生测定两次。结果：除不同测定者定性测定左冠状动脉主干钙化的结果差别显著（ｐ＜００２５）外，其余结果均无显著差异。定量测定的相关系数为０．８９８～０９。结论：在电子束ＣＴ图像上可准确地重复测得冠状动脉钙化定性、定量结果。     

国人冠状动脉钙化的电子束CT检测结果及其临床意义

目的了解电子束ＣＴ（ＥＢＣＴ）检测冠状动脉钙化（ＣＡＣ）在国人中的状况；探讨其在临床冠心病诊断和预测中的价值和限度。材料与方法对经ＩｍａｔｒｏｎＣ－１５０型ＥＢＣＴ机检测ＣＡＣ的７１８例受检者进行研究。分析ＣＡＣ率和积分与年龄、性别及临床冠心病发病的关系，评价其对临床冠心病的诊断和预测价值。结果本研究中男性组的ＣＡＣ率为６５．３％，显著高于女性组（４５．５％，Ｐ＜０．００１）；男、女组ＣＡＣ率和积分均随年龄增加而显著增高（Ｐ＜０．００１）；冠心病组ＣＡＣ率与国外报道相仿，而ＣＡＣ积分却明显低于西方人；非冠心病组的ＣＡＣ率、积分均明显低于文献报道（３０～３９岁年龄段除外）；各年龄段冠心病组的ＣＡＣ率和积分均显著高于非冠心病组（Ｐ＜０．０５）。结论ＥＢＣＴ测定的国人ＣＡＣ与文献报道的西方人有一定差别；无ＣＡＣ或其积分较高对冠心病发病危险性预测的价值较大，有ＣＡＣ，但其积分较低时，对冠心病的诊断和预测应结合临床确定。     

^99mTc—MIBI心肌灌注显像与电子束CT诊断冠心病的比较

目的比较９９ｍＴｃ甲氧基异丁基异腈（ＭＩＢＩ）心肌ＳＰＥＣＴ显像与电子束ＣＴ（ＥＢＣＴ）冠状动脉钙化（ＣＡＣ）定量积分对冠心病诊断的价值。方法２１例经冠状动脉造影确诊的病人同时进行９９ｍＴｃＭＩＢＩ心肌ＳＰＥＣＴ显像（潘生丁介入试验）及ＥＢＣＴ检查，以冠状动脉造影为金标准，以决策矩阵法评价心肌ＳＰＥＣＴ及ＥＢＣＴ的临床应用价值。结果心肌ＳＰＥＣＴ显像灵敏度为９１％，特异性为８０％，准确性为８６％；ＥＢＣＴ以钙化积分≥１００为阳性标准，则其灵敏度、特异性和准确性分别为５５％、１００％及７６％。结论心肌ＳＰＥＣＴ显像和ＥＢＣＴ冠状动脉ＣＡＣ定量积分法均为非创伤性检查法，对冠心病的诊断各具优势及局限性，有互补作用     

核素心肌灌注显像与电子束CT诊断冠心病的对比研究

目的比较核素心肌ＳＰＥＣＴ显像与电子束ＣＴ（ＥＢＣＴ）扫描对冠心病（ＣＨＤ）的诊断价值。方法对６４例受检者（ＣＨＤ患者５０例，非ＣＨＤ患者１４例）进行了冠状动脉造影、ＳＰＥＣＴ及ＥＢＣＴ检查。结果以冠状动脉造影为金标准，ＳＰＥＣＴ与ＥＢＣＴ诊断ＣＨＤ的灵敏度相近，分别为９２０％和９４０％；ＳＰＥＣＴ的特异性（９２９％）优于ＥＢＣＴ（２８６％），Ｐ＜００５。在判断ＥＢＣＴ结果时，采用不同的钙化积分阈值，对诊断ＣＨＤ的灵敏度和特异性影响很大，故应采用接收器工作特性分析确定适当的钙化积分阈值。结论ＥＢＣＴ虽具有一定优越性，但目前尚不能取代心肌ＳＰＥＣＴ显像。     

冠状动脉钙化电子束CT的定量研究

评价国人冠心病患者冠脉钙化的发生率和定量分析钙化的严重程度。材料和方法：对28例冠心病组患者和57例对照组进行电子束成像系统（EBIS）心脏扫描，检测钙化的发生率，计算钙化积分进行定量分析。结果：冠心病组中，60岁及以下组和60岁以上组冠脉钙化发生率均高于对照组，差异有显著性（77．78％对22．73％，P＜0．01；90．42％对38．46％，P＜0．01）；冠脉钙化总积分明显高于对照组（249．21±547．54对8．74±26．12，P＜0．01）。结论：国人冠心病患者的冠钙化发生率和钙化积分均明显高于对照组，电子束成像系统是一种评价冠心病较好的非创伤性办法。     

电子束CT检出冠状动脉钙化及其与心肌灌注显像的对比研究

目的比较电子束ＣＴ（ＥＢＣＴ）检查冠状动脉钙化（ＣＡＣ）及核素心肌灌注显像（ＭＰＩ）评价冠心病（ＣＨＤ）的价值。材料与方法本组５０例均为临床疑诊或确诊为ＣＨＤ患者。所有患者均行ＥＢＣＴ、ＭＰＩ及冠状动脉造影。结果４０例患者共８４支血管冠状动脉造影证实有明显的冠状动脉病变（ＣＡＤ）（狭窄＞５０％），其中１４例为单支病变，８例为双支病变，１８例为三支病变，另有１０例冠状动脉造影正常。ＥＢＣＴ预测ＣＡＤ的敏感性、特异性及准确性为８３％、８０％及８２％，ＭＰＩ预测ＣＡＤ的敏感性、特异性及准确性分别为８５％、８０％及８４％，ＥＢＣＴ与ＭＰＩ的结果间无显著性差异（Ｐ＞０．０５）。ＣＡＣ血管供血区出现心肌缺血者达６５％。结论ＣＡＣ是预测ＣＡＤ的有价值指标。在有症状的人群中ＥＢＣＴ检出ＣＡＣ预测ＣＡＤ的敏感性、特异性及准确性与ＭＰＩ相似。有症状人群中检出ＣＡＣ患者多有心肌缺血或梗死，因此为早期诊断冠心病，应对无症状人群进行筛选。     

心肌灌注断层显像和电子束CT检查不同年龄冠心病的比较研究

目的 比较心肌灌注断层显像（ＭＰＩ）和电子束ＣＴ（ＥＢＣＴ）诊断〉４５岁与≤４５岁（ＣＡＤ）患者的价值。方法 将６４例临床拟诊为ＣＡＤ的患者按年龄分为Ａ组和Ｂ组。均进行ＥＢＣＴ探查冠状动脉钙化,＾９９Ｔｃ＾ｍ－甲氧基异丁基异腈（ＭＩＢＩ）ＭＰＩ和冠状动脉造影（ＣＡＧ）。     

CT定量测量腹部脂肪面积的研究

目的：确定ＣＴ定量测量腹部脂肪面积的价值。方法：对３５ 例病人进行ＣＴ定量测量腹部脂肪面积。结果：腹内与皮下脂肪面积比值（Ｉ／Ｓ）≥０．６者易患中风、高血压、高脂血症等病（Ｐ＜ ０．００１）,其敏感性９４％ ,特异性６７％ ,准确性８０％ 。结论：ＣＴ定量测量腹部脂肪面积是一种检查肥胖并发症的有效手段,正常人腹内与皮下脂肪面积的比值应＜ ０．６。     

多层螺旋CT检测冠状动脉钙化的方法及临床价值

目的：探讨16层螺旋CT检测冠状动脉钙化的方法，初步评估其临床应用价值。材料和方法：采用西门子16层螺旋CT（Siemens Somatom Sensation 16）对选定的50例患者（分临床冠心组和临床非冠心组，各25例）做心脏螺旋扫描，以层厚3mrn重建后，对各层面冠状动脉钙化检测并作积分分析。结果：16层螺旋CT能清晰显示冠状动脉钙化，定量积分数据有稳定性和重复性。临床冠心组的钙化积分定量显著高于临床非冠心组。结论：1．16层螺旋CT对于冠状动脉钙化的检出有较为突出的价值，其敏感性和准确性均较高，因此适合作为冠心病的普查手段。2．钙化仅仅是冠脉粥样硬化的指征之一，不是管腔严重狭窄的标志，不能预测血管狭窄程度，但钙化积分值与冠状动脉病变的严重程度相关。     

电子束CT双期扫描定量估价胰腺增强程度

目的：定量估价电子束ＣＴ双期扫描胰腺的增强程度。材料和方法：１１０例可疑胰腺病变者（２６～７２岁）均行电子束ＣＴ检查。其中胰腺癌１５例，胰腺炎３例，胰腺外伤２例，正常胰腺９０例。应用高压注射器以３．５ｍｌ／秒（８０ｍｌ）和１０ｍｌ／秒（２０ｍｌ）速度注射Ｕｌｔｒａｖｉｓｔ１００ｍｌ，在注射造影剂后１８～２０秒和５５～６０秒，应用ＳＶＳ０．３秒序列扫描胰腺２０层，层厚６ｍｍ。于动静脉期测量胰腺头、体、尾ＣＴ值。结果：在动脉期胰腺增强的ＣＴ值为１０１Ｈｕ±８（标准差），静脉期为８１Ｈｕ±５。其中６１例（５５％）动脉期较静脉期ＣＴ值增高２０Ｈｕ以上；３８例（３４％）增高１０Ｈｕ以上；１１例（１０％）动脉期ＣＴ值低于静脉期。结论：胰腺动脉期扫描较静脉期可提供更详细的解剖结构，可更清楚显示胰腺癌对胰周的浸润，可提高检测胰腺内小病灶的准确性。     

Coronary artery calcium scoring using 16-MDCT and a retrospective ECG-gating reconstruction algorithm

OBJECTIVE: Our aim was to compare detection, quantification, and cardiovascular risk stratification of coronary artery calcium (CAC) between electron beam CT and 16-MDCT with retrospective reconstruction. SUBJECTS AND METHODS. One hundred patients underwent both electron beam CT and 16-MDCT, and coronary artery calcium score, volume, and mass were obtained. RESULTS: Correlation between the two CT scanners was high for both calcium score (r(2) = 0.955), volume (r(2) = 0.952), and mass (r(2) = 0.977). Although electron beam CT is viewed as the gold standard, the sensitivity and specificity in the detection of CAC using 16-MDCT with a threshold of 130 H were 98.7% and 100%, respectively. The variability of calcium scores between the two CT scanners (26.5%) was comparable with two electron beam CT scanners reported previously. The variability of calcium volume (20.7%) and mass (20.3%) was lower than that of the score (Student's t test, r = 0.05, 0.01). In clinical cardiovascular risk stratification based on two CT calcium scores, the Cohen's kappa value was 0.929. There was no significant difference between the two scanners using Wilcoxon's signed rank test (p = 0.157). CONCLUSION: The 16-MDCT scanner with retrospective reconstruction, showing high agreement for detection and quantification of CAC with electron beam CT, holds promise in the detection of coronary artery atherosclerosis.     

电子束CT血管造影对冠状动脉疾病的诊断与随访

目的评价电子束CT血管造影(EBA)及其三维血管成像技术对冠状动脉疾病的诊断与随访价值. 资料与方法 87例经EBA检查的患者,其中支架置入术后随访16例,搭桥术后随访9例.除9例搭桥患者外,其余78例均有冠状动脉造影(CAG)结果证实. 结果 EBA可评价的冠状动脉中,对左主干和前降支的诊断敏感性、特异性最高,尤其是近段,其次为右冠,对回旋支的诊断敏感性和特异性则较低;16例支架置入术后患者共放置支架47枚,EBA准确定位45枚(95.7%),对支架内开通诊断的符合率为74.5%;9例冠状动脉搭桥术后的患者,共搭建冠状动脉桥血管27支,EBA对桥血管开通与否诊断的符合率为81.5%. 结论 EBA对冠状动脉狭窄的诊断具有较高的术前筛选价值,对术后的随访也有较大的潜力,是一项很有优势的无创性冠心病检查方法.     

Electron beam CT versus 16-MDCT on the variability of repeated coronary artery calcium measurements in a variable heart rate phantom

OBJECTIVE: High reproducibility of coronary artery calcium (CAC) scoring is a key requirement for monitoring the progression of coronary atherosclerosis. The purposes of this study were to compare electron beam CT and 16-MDCT scanners in the variability of repeated CAC measurements and to assess the factors influencing this variability. MATERIALS AND METHODS: CAC models of different sizes attached to a cardiac phantom with a programmable variable heart rate were scanned three times, and interscan variability of the CAC measurement was calculated each time. For helical CT, different slice-thickness images of either retrospective ECG-gated or prospective ECG-triggering reconstruction were obtained. The detection of small amounts of calcium, variability of the Agatston score, and CAC measurement algorithms (Agatston, volume, and mass scores) were compared between CT scanners and protocols. RESULTS: All 1-mm-sized calcium models were detected on 0.625- and 1.25-mm helical CT, whereas some were missed on electron beam CT and 2.5-mm helical CT. Retrospective ECG-gated thin-slice helical CT showed the lowest variability. Reduction of variability by volume and mass scoring algorithms was less effective on 0.625- and 1.25-mm-thickness CT. CONCLUSION: Retrospective ECG-gated thin-slice helical CT has the potential to be a useful tool for monitoring coronary atherosclerosis.     

Prevalence of silent myocardial ischemia in asymptomatic individuals with subclinical atherosclerosis detected by electron beam tomography

BACKGROUND: Electron beam tomography coronary calcium imaging is an evolving technique for the early detection of coronary atherosclerosis, and recent studies have established its prognostic value in asymptomatic individuals. The relationship of coronary artery calcium scores (CAC) to obstructive coronary artery disease (CAD) has been poorly studied but is clinically relevant because it determines which individuals are likely to benefit from revascularization procedures. Hence, we prospectively evaluated the prevalence of myocardial ischemia in asymptomatic patients with cardiovascular risk factors and subclinical atherosclerosis. METHODS AND RESULTS: We studied 864 asymptomatic patients with no previous CAD but with cardiovascular risk factors, referred for electron beam tomography coronary calcium imaging to our institution over an 18-month period. From this group, 220 consecutive patients (85% men; mean age, 61 +/- 9 years; age range, 31-84 years) with moderate to severe atherosclerotic disease (coronary calcium score > or =100 Agatston units) were prospectively evaluated by technetium 99m sestamibi single photon emission computed tomography (SPECT). Patients were followed up (mean follow-up, 14 months) and data regarding their subsequent clinical management recorded. Of the 220 patients, 119 had moderate atherosclerosis (CAC score of 100-400 Agatston units) and 101 had severe atherosclerosis (CAC score > or =400 Agatston units). Abnormal SPECT findings were seen in 18% of patients with moderate atherosclerosis (n = 21) and 45% of patients with severe atherosclerosis (n = 45). Increasing severity of atherosclerosis was related to increasing ischemic burden (summed difference score = 1 +/- 0.2 for CAC score of 100-400 Agatston units and 3.2 +/- 0.5 for CAC score > or =400 Agatston units). In a multivariate linear regression model incorporating risk factors, CAC was the only predictor of silent ischemia. CONCLUSION: In comparison to previously published data, we detected a higher prevalence of silent ischemia even in patients with moderate coronary atherosclerosis (18%). This may reflect the differing risk factor profile of our patient population. When coronary calcium screening is used to preselect asymptomatic patients with cardiovascular risk factors for myocardial perfusion imaging, the optimum coronary calcium score threshold will depend on the population prevalence of risk factors and asymptomatic obstructive CAD.     

中低心率患者在双源CT低管电压冠状动脉成像中的图像质量及辐射剂量

目的 探讨中低心率对双源CT低管电压冠状动脉成像的图像质量及辐射剂量的影响.方法 对85例体质量指数(BMI)为17.51～30.00 kg/m2、心率在91次/min(bpm)以下的可疑冠心病患者进行双源CT低管电压(100 kVp)回顾性心电门控冠状动脉成像增强扫描,检查前不使用β受体阻滞剂控制心率.按患者扫描时的心率进行分组,≤59 bpm为A组(27例),60～69 bpm为B组(29例),≥70 bpm为C组(29例).评价各组的最佳重建时相图像,记录各组的增强扫描序列的螺距、CT容积剂量指数(CTDvol)、剂量长度乘积(DLP)及有效剂量(ED)值.应用单因素方差分析比较3组患者的扫描螺距、图像质量评分和辐射剂量值等.分析心率对冠状动脉成像图像质量及辐射剂量的影响.结果 A、B、C组螺距分别为0.241±0.025、0.286±0.034、0.335±0.036;3组图像质量评分分别为(4.78±0.26)、(4.66±0.56)、(4.70±0.46)分;CTDIvol值分别为(18.06±5.16)、(19.62±7.15)和(17.50±7.13)mGy,ED值分别为(4.23±1.16)、(4.59±1.75)、(4.12±1.39)mSv.3组的螺距差异有统计学意义(F=60.00,P=0.00);3组间的图像质量评分差异无统计学意义(F=0.53,P=0.59);3组间CTDIvol差异无统计学意义(F=0.83,P=0.44),ED差异也无统计学意义(F=0.86,P=0.43).结论 中低心率对双源CT低管电压冠状动脉成像的图像质量影响很小,在自动心电门控剂量窗时,对辐射剂量的影响也很小.

Abstract：

Objective To evaluate the imaging quality and radiation doses of dual-source computed tomography (DSCT) coronary angiography at a low tube voltage in patients with medium and low heart rate.Methods Eighty-five patients[heart rate (HR) ＜ 91 beats per minute (bpm); body mass index (BMI) 17. 51-30. 00 kg/m2]suspected of coronary artery disease received retrospectively ECG-gating coronary angiography with dual-source CT scanner (Somatom Definition, Siemens) at a tube voltage of 100 kVp. For all patients, no beta-blocker was used before CT scan. According to the HR, the patients were divided into three groups: Group A, HR ≤ 59 bpm, n = 27; Group B, HR 60-69 bpm, n = 29; Group C,HR ≥70 bpm, n = 29. All images were transferred to a workstation for postprocessing. The best R-R interval reconstruction images of all groups were evaluated. The value of pitch, CT volume dosage index (CTDIvol), dose length product (DLP)and effective dose (ED)were recorded. The pitch, the score of imaging quality of coronary artery segments and the radiation dose were compared with one-way ANOVA. The influence of HR on image quality and radiation doses of coronary artery was analyzed. Results The value of pitch in Group A, Group B and Group C was 0. 241 ± 0. 025, 0. 286 ± 0. 034 and 0. 335 ± 0. 036,respectively. The mean score of imaging quality of coronary artery segments in Group A, Group B and Group C was 4. 78 ± 0. 26, 4. 66 ± 0. 56 and 4. 70 ± 0. 46, respectively. The value of CTDIvol in Group A,Group B and Group C was (18.06 ±5. 16), (19. 62 ±7. 15) and (17. 50 ±7. 13) mGy, respectively. The value of ED in group A, Group B and Group C was (4.23 ± 1.76), (4.59 ± 1.75) and (4.12 ±1.39) mSv, respectively. There was statistical difference in value of pitch among the three groups (F =60. 00, P= 0. 00). There were no statistical difference in score of imaging quality, CTDIvol and value of ED among the three groups (F = 0. 53, P = 0. 59; F = 0. 83, P = 0. 44 ; F = 0. 86, P = 0. 43). Conclusion Medium and low HR have little influences on image quality of dual-source CT coronary angiography at a low tube voltage. When the auto ECG-gating is selected, there is little influence on radiation dosage as well.     

冠状动脉钙化CT检出率及其意义的探讨

我们使用ＥＬＳＣＩＮＴ２４００型全身ＣＴ扫描机，连续对２０５例胸部进行平扫检查，发现冠脉钙化４４例，占２１．５％。５０例４０岁以下者未发现冠脉钙化；１５５例４０岁以上者，冠脉钙化检出率随着年龄增加而增加，其中５８例诊断冠心病，４０例有冠脉钙化；９７例无冠心病者，４例有冠脉钙化。着重探讨冠脉钙化与冠心病的关系，其灵敏度、特异度及阳性予告值分别为６９％、９６％及９１％。ＣＴ检出冠脉钙化虽不很敏感，但却能说明发生冠心病的机率较高，因而仍应将它视为一种重要的非损伤性检查方法。     

A method for calcium quantification by means of CT coronary angiography using 64-multidetector CT: very high correlation with agatston and volume scores

To find out whether calcium scoring of the coronary arteries (CAC scoring) could be carried out with a CT angiography of the coronary arteries (CTCA) in a single CT data acquisition. The Agatston and V130 scores for 113 patients were assessed. A calcium volume score (V600 score) was compiled from the CTCA data sets. Intra- and interobserver correlations were excellent (ρ > 0.97). The intra- and interobserver repeatability coefficients were extremely low, increasing in magnitude from the V600 score to the V130 and Agatston scores. The V600 score underestimates the coronary calcium burden. However, it has a linear relation to the Agatston and V130 scores. Thus, they are predictable from the values of the V600 score. The V600 score shows a linear relation to the classic CAC scores. Due to its extremely high reliability, the score may be a feasible alternative for classic CAC scoring methods in order to reduce radiation dosages.     

肺癌CT普查的同时进行冠状动脉和主动脉钙化筛查的探讨

目的探讨肺癌CT普查的同时进行冠状动脉和主动脉钙化筛查。方法1877例健康体检者行螺旋CT肺癌普查,标准纵隔窗观察冠状动脉及主动脉钙化情况。结果(1)1877例被检者冠状动脉钙化总阳性率为15%,男性阳性率显著高于女性(P<0.05),两性的阳性率都随年龄的增加而增高;(2)全部被检者胸主动脉钙化总阳性率为20.88%,男性阳性率与女性无差别(P>0.05),男性及女性主动脉钙化阳性率随年龄的增加而增高,主动脉钙化的部位最常见为主动脉弓部,最少见于升主动脉。结论肺癌CT普查的同时可以筛查冠状动脉及主动脉钙化,冠状动脉及主动脉钙化的检出对冠心病的诊断具有重要的临床意义。