前瞻性心电门控双源CT冠状动脉成像在高心率患者中应用的可行性研究

Objective To explore the optimal reconstruction windows in patients with heart rate (HR) over 91 (beats per minute) bpm, and to explore the feasibility of prospective ECG-gated DSCT coronary angiography.Methods Two hundred and thirty-two patients[body mass index (BMI):23-25 kg/m2, with stable HR, and average HR ≥91 bpm]with suspected or known coronary artery disease underwent retrospective ECG-gated DSCT coronary angiography.They were divided into 3 groups (A-C) according to the average HR of scanning.Images were reconstructed from 29% to 80% of the R-R interval in 3% increments.Two independent readers assessed the overall image quality by a five-point scale and determined the optimal reconstruction windows of each coronary segment and the ranges.Coronary arteries were segmented according to the guideline of the American Heart Association (AHA).The degree of interobserver agreement was determined by Kappa statistics.Results Three thousand three hundred and fortythree segments were considered to have diagnostic image quality in 232 patients.The ranges of optimal reconstruction windows of images were concentrated on 81%-61% and 51%-31%.In group A(91-95 bpm), there were 1183 segments in 83 patients, and the according proportions were 5.49%, 94.51%,respectively; In group B(96-100 bpm), there were 986 segments in 68 patients, and the according proportions were 0.20%, 99.80%, respectively; In group C(≥ 101 bpm), there were 1174 segments in 81 patients, and the according proportions were 0.17%, 99.83%, respectively.The optimal construction windows in 3274 segments out of 3343 segments in 232 patients were concentrated in 41%, ranged from 51%-31%.The image quality assessment in 3343 segments in 232 patients have a high inter-observe agreement (Kappa=0.883,P <0.05).Conclusion The optimal reconstruction windows of patients with stable HR(≥91 bpm) was concentrated in 41%, ranged from 51%-31%.When nothing except the window of data acquisition is considered, the prospective ECC,-gated DSCT coronary angingraphy can be used in patients with stable HR(≥91 bpm).     

前瞻性心电门控双源CT冠状动脉成像在高心率患者中应用的可行性研究

Objective To explore the optimal reconstruction windows in patients with heart rate (HR) over 91 (beats per minute) bpm, and to explore the feasibility of prospective ECG-gated DSCT coronary angiography.Methods Two hundred and thirty-two patients[body mass index (BMI):23-25 kg/m2, with stable HR, and average HR ≥91 bpm]with suspected or known coronary artery disease underwent retrospective ECG-gated DSCT coronary angiography.They were divided into 3 groups (A-C) according to the average HR of scanning.Images were reconstructed from 29% to 80% of the R-R interval in 3% increments.Two independent readers assessed the overall image quality by a five-point scale and determined the optimal reconstruction windows of each coronary segment and the ranges.Coronary arteries were segmented according to the guideline of the American Heart Association (AHA).The degree of interobserver agreement was determined by Kappa statistics.Results Three thousand three hundred and fortythree segments were considered to have diagnostic image quality in 232 patients.The ranges of optimal reconstruction windows of images were concentrated on 81%-61% and 51%-31%.In group A(91-95 bpm), there were 1183 segments in 83 patients, and the according proportions were 5.49%, 94.51%,respectively; In group B(96-100 bpm), there were 986 segments in 68 patients, and the according proportions were 0.20%, 99.80%, respectively; In group C(≥ 101 bpm), there were 1174 segments in 81 patients, and the according proportions were 0.17%, 99.83%, respectively.The optimal construction windows in 3274 segments out of 3343 segments in 232 patients were concentrated in 41%, ranged from 51%-31%.The image quality assessment in 3343 segments in 232 patients have a high inter-observe agreement (Kappa=0.883,P <0.05).Conclusion The optimal reconstruction windows of patients with stable HR(≥91 bpm) was concentrated in 41%, ranged from 51%-31%.When nothing except the window of data acquisition is considered, the prospective ECC,-gated DSCT coronary angingraphy can be used in patients with stable HR(≥91 bpm).     

前瞻性心电门控双源CT冠状动脉成像在高心率患者中应用的可行性研究

Objective To explore the optimal reconstruction windows in patients with heart rate (HR) over 91 (beats per minute) bpm, and to explore the feasibility of prospective ECG-gated DSCT coronary angiography.Methods Two hundred and thirty-two patients[body mass index (BMI):23-25 kg/m2, with stable HR, and average HR ≥91 bpm]with suspected or known coronary artery disease underwent retrospective ECG-gated DSCT coronary angiography.They were divided into 3 groups (A-C) according to the average HR of scanning.Images were reconstructed from 29% to 80% of the R-R interval in 3% increments.Two independent readers assessed the overall image quality by a five-point scale and determined the optimal reconstruction windows of each coronary segment and the ranges.Coronary arteries were segmented according to the guideline of the American Heart Association (AHA).The degree of interobserver agreement was determined by Kappa statistics.Results Three thousand three hundred and fortythree segments were considered to have diagnostic image quality in 232 patients.The ranges of optimal reconstruction windows of images were concentrated on 81%-61% and 51%-31%.In group A(91-95 bpm), there were 1183 segments in 83 patients, and the according proportions were 5.49%, 94.51%,respectively; In group B(96-100 bpm), there were 986 segments in 68 patients, and the according proportions were 0.20%, 99.80%, respectively; In group C(≥ 101 bpm), there were 1174 segments in 81 patients, and the according proportions were 0.17%, 99.83%, respectively.The optimal construction windows in 3274 segments out of 3343 segments in 232 patients were concentrated in 41%, ranged from 51%-31%.The image quality assessment in 3343 segments in 232 patients have a high inter-observe agreement (Kappa=0.883,P <0.05).Conclusion The optimal reconstruction windows of patients with stable HR(≥91 bpm) was concentrated in 41%, ranged from 51%-31%.When nothing except the window of data acquisition is considered, the prospective ECC,-gated DSCT coronary angingraphy can be used in patients with stable HR(≥91 bpm).     

前瞻性心电门控双源CT冠状动脉成像在高心率患者中应用的可行性研究

Objective To explore the optimal reconstruction windows in patients with heart rate (HR) over 91 (beats per minute) bpm, and to explore the feasibility of prospective ECG-gated DSCT coronary angiography.Methods Two hundred and thirty-two patients[body mass index (BMI):23-25 kg/m2, with stable HR, and average HR ≥91 bpm]with suspected or known coronary artery disease underwent retrospective ECG-gated DSCT coronary angiography.They were divided into 3 groups (A-C) according to the average HR of scanning.Images were reconstructed from 29% to 80% of the R-R interval in 3% increments.Two independent readers assessed the overall image quality by a five-point scale and determined the optimal reconstruction windows of each coronary segment and the ranges.Coronary arteries were segmented according to the guideline of the American Heart Association (AHA).The degree of interobserver agreement was determined by Kappa statistics.Results Three thousand three hundred and fortythree segments were considered to have diagnostic image quality in 232 patients.The ranges of optimal reconstruction windows of images were concentrated on 81%-61% and 51%-31%.In group A(91-95 bpm), there were 1183 segments in 83 patients, and the according proportions were 5.49%, 94.51%,respectively; In group B(96-100 bpm), there were 986 segments in 68 patients, and the according proportions were 0.20%, 99.80%, respectively; In group C(≥ 101 bpm), there were 1174 segments in 81 patients, and the according proportions were 0.17%, 99.83%, respectively.The optimal construction windows in 3274 segments out of 3343 segments in 232 patients were concentrated in 41%, ranged from 51%-31%.The image quality assessment in 3343 segments in 232 patients have a high inter-observe agreement (Kappa=0.883,P <0.05).Conclusion The optimal reconstruction windows of patients with stable HR(≥91 bpm) was concentrated in 41%, ranged from 51%-31%.When nothing except the window of data acquisition is considered, the prospective ECC,-gated DSCT coronary angingraphy can be used in patients with stable HR(≥91 bpm).     

前瞻性心电门控双源CT冠状动脉成像在高心率患者中应用的可行性研究

Objective To explore the optimal reconstruction windows in patients with heart rate (HR) over 91 (beats per minute) bpm, and to explore the feasibility of prospective ECG-gated DSCT coronary angiography.Methods Two hundred and thirty-two patients[body mass index (BMI):23-25 kg/m2, with stable HR, and average HR ≥91 bpm]with suspected or known coronary artery disease underwent retrospective ECG-gated DSCT coronary angiography.They were divided into 3 groups (A-C) according to the average HR of scanning.Images were reconstructed from 29% to 80% of the R-R interval in 3% increments.Two independent readers assessed the overall image quality by a five-point scale and determined the optimal reconstruction windows of each coronary segment and the ranges.Coronary arteries were segmented according to the guideline of the American Heart Association (AHA).The degree of interobserver agreement was determined by Kappa statistics.Results Three thousand three hundred and fortythree segments were considered to have diagnostic image quality in 232 patients.The ranges of optimal reconstruction windows of images were concentrated on 81%-61% and 51%-31%.In group A(91-95 bpm), there were 1183 segments in 83 patients, and the according proportions were 5.49%, 94.51%,respectively; In group B(96-100 bpm), there were 986 segments in 68 patients, and the according proportions were 0.20%, 99.80%, respectively; In group C(≥ 101 bpm), there were 1174 segments in 81 patients, and the according proportions were 0.17%, 99.83%, respectively.The optimal construction windows in 3274 segments out of 3343 segments in 232 patients were concentrated in 41%, ranged from 51%-31%.The image quality assessment in 3343 segments in 232 patients have a high inter-observe agreement (Kappa=0.883,P <0.05).Conclusion The optimal reconstruction windows of patients with stable HR(≥91 bpm) was concentrated in 41%, ranged from 51%-31%.When nothing except the window of data acquisition is considered, the prospective ECC,-gated DSCT coronary angingraphy can be used in patients with stable HR(≥91 bpm).     

前瞻性心电门控双源CT冠状动脉成像在高心率患者中应用的可行性研究

Objective To explore the optimal reconstruction windows in patients with heart rate (HR) over 91 (beats per minute) bpm, and to explore the feasibility of prospective ECG-gated DSCT coronary angiography.Methods Two hundred and thirty-two patients[body mass index (BMI):23-25 kg/m2, with stable HR, and average HR ≥91 bpm]with suspected or known coronary artery disease underwent retrospective ECG-gated DSCT coronary angiography.They were divided into 3 groups (A-C) according to the average HR of scanning.Images were reconstructed from 29% to 80% of the R-R interval in 3% increments.Two independent readers assessed the overall image quality by a five-point scale and determined the optimal reconstruction windows of each coronary segment and the ranges.Coronary arteries were segmented according to the guideline of the American Heart Association (AHA).The degree of interobserver agreement was determined by Kappa statistics.Results Three thousand three hundred and fortythree segments were considered to have diagnostic image quality in 232 patients.The ranges of optimal reconstruction windows of images were concentrated on 81%-61% and 51%-31%.In group A(91-95 bpm), there were 1183 segments in 83 patients, and the according proportions were 5.49%, 94.51%,respectively; In group B(96-100 bpm), there were 986 segments in 68 patients, and the according proportions were 0.20%, 99.80%, respectively; In group C(≥ 101 bpm), there were 1174 segments in 81 patients, and the according proportions were 0.17%, 99.83%, respectively.The optimal construction windows in 3274 segments out of 3343 segments in 232 patients were concentrated in 41%, ranged from 51%-31%.The image quality assessment in 3343 segments in 232 patients have a high inter-observe agreement (Kappa=0.883,P <0.05).Conclusion The optimal reconstruction windows of patients with stable HR(≥91 bpm) was concentrated in 41%, ranged from 51%-31%.When nothing except the window of data acquisition is considered, the prospective ECC,-gated DSCT coronary angingraphy can be used in patients with stable HR(≥91 bpm).     

前瞻性心电门控双源CT冠状动脉成像在高心率患者中应用的可行性研究

Objective To explore the optimal reconstruction windows in patients with heart rate (HR) over 91 (beats per minute) bpm, and to explore the feasibility of prospective ECG-gated DSCT coronary angiography.Methods Two hundred and thirty-two patients[body mass index (BMI):23-25 kg/m2, with stable HR, and average HR ≥91 bpm]with suspected or known coronary artery disease underwent retrospective ECG-gated DSCT coronary angiography.They were divided into 3 groups (A-C) according to the average HR of scanning.Images were reconstructed from 29% to 80% of the R-R interval in 3% increments.Two independent readers assessed the overall image quality by a five-point scale and determined the optimal reconstruction windows of each coronary segment and the ranges.Coronary arteries were segmented according to the guideline of the American Heart Association (AHA).The degree of interobserver agreement was determined by Kappa statistics.Results Three thousand three hundred and fortythree segments were considered to have diagnostic image quality in 232 patients.The ranges of optimal reconstruction windows of images were concentrated on 81%-61% and 51%-31%.In group A(91-95 bpm), there were 1183 segments in 83 patients, and the according proportions were 5.49%, 94.51%,respectively; In group B(96-100 bpm), there were 986 segments in 68 patients, and the according proportions were 0.20%, 99.80%, respectively; In group C(≥ 101 bpm), there were 1174 segments in 81 patients, and the according proportions were 0.17%, 99.83%, respectively.The optimal construction windows in 3274 segments out of 3343 segments in 232 patients were concentrated in 41%, ranged from 51%-31%.The image quality assessment in 3343 segments in 232 patients have a high inter-observe agreement (Kappa=0.883,P <0.05).Conclusion The optimal reconstruction windows of patients with stable HR(≥91 bpm) was concentrated in 41%, ranged from 51%-31%.When nothing except the window of data acquisition is considered, the prospective ECC,-gated DSCT coronary angingraphy can be used in patients with stable HR(≥91 bpm).     

前瞻性心电门控双源CT冠状动脉成像在高心率患者中应用的可行性研究

Objective To explore the optimal reconstruction windows in patients with heart rate (HR) over 91 (beats per minute) bpm, and to explore the feasibility of prospective ECG-gated DSCT coronary angiography.Methods Two hundred and thirty-two patients[body mass index (BMI):23-25 kg/m2, with stable HR, and average HR ≥91 bpm]with suspected or known coronary artery disease underwent retrospective ECG-gated DSCT coronary angiography.They were divided into 3 groups (A-C) according to the average HR of scanning.Images were reconstructed from 29% to 80% of the R-R interval in 3% increments.Two independent readers assessed the overall image quality by a five-point scale and determined the optimal reconstruction windows of each coronary segment and the ranges.Coronary arteries were segmented according to the guideline of the American Heart Association (AHA).The degree of interobserver agreement was determined by Kappa statistics.Results Three thousand three hundred and fortythree segments were considered to have diagnostic image quality in 232 patients.The ranges of optimal reconstruction windows of images were concentrated on 81%-61% and 51%-31%.In group A(91-95 bpm), there were 1183 segments in 83 patients, and the according proportions were 5.49%, 94.51%,respectively; In group B(96-100 bpm), there were 986 segments in 68 patients, and the according proportions were 0.20%, 99.80%, respectively; In group C(≥ 101 bpm), there were 1174 segments in 81 patients, and the according proportions were 0.17%, 99.83%, respectively.The optimal construction windows in 3274 segments out of 3343 segments in 232 patients were concentrated in 41%, ranged from 51%-31%.The image quality assessment in 3343 segments in 232 patients have a high inter-observe agreement (Kappa=0.883,P <0.05).Conclusion The optimal reconstruction windows of patients with stable HR(≥91 bpm) was concentrated in 41%, ranged from 51%-31%.When nothing except the window of data acquisition is considered, the prospective ECC,-gated DSCT coronary angingraphy can be used in patients with stable HR(≥91 bpm).     

前瞻性心电门控双源CT冠状动脉成像在高心率患者中应用的可行性研究

Objective To explore the optimal reconstruction windows in patients with heart rate (HR) over 91 (beats per minute) bpm, and to explore the feasibility of prospective ECG-gated DSCT coronary angiography.Methods Two hundred and thirty-two patients[body mass index (BMI):23-25 kg/m2, with stable HR, and average HR ≥91 bpm]with suspected or known coronary artery disease underwent retrospective ECG-gated DSCT coronary angiography.They were divided into 3 groups (A-C) according to the average HR of scanning.Images were reconstructed from 29% to 80% of the R-R interval in 3% increments.Two independent readers assessed the overall image quality by a five-point scale and determined the optimal reconstruction windows of each coronary segment and the ranges.Coronary arteries were segmented according to the guideline of the American Heart Association (AHA).The degree of interobserver agreement was determined by Kappa statistics.Results Three thousand three hundred and fortythree segments were considered to have diagnostic image quality in 232 patients.The ranges of optimal reconstruction windows of images were concentrated on 81%-61% and 51%-31%.In group A(91-95 bpm), there were 1183 segments in 83 patients, and the according proportions were 5.49%, 94.51%,respectively; In group B(96-100 bpm), there were 986 segments in 68 patients, and the according proportions were 0.20%, 99.80%, respectively; In group C(≥ 101 bpm), there were 1174 segments in 81 patients, and the according proportions were 0.17%, 99.83%, respectively.The optimal construction windows in 3274 segments out of 3343 segments in 232 patients were concentrated in 41%, ranged from 51%-31%.The image quality assessment in 3343 segments in 232 patients have a high inter-observe agreement (Kappa=0.883,P <0.05).Conclusion The optimal reconstruction windows of patients with stable HR(≥91 bpm) was concentrated in 41%, ranged from 51%-31%.When nothing except the window of data acquisition is considered, the prospective ECC,-gated DSCT coronary angingraphy can be used in patients with stable HR(≥91 bpm).     

前瞻性心电门控双源CT冠状动脉成像在高心率患者中应用的可行性研究

Objective To explore the optimal reconstruction windows in patients with heart rate (HR) over 91 (beats per minute) bpm, and to explore the feasibility of prospective ECG-gated DSCT coronary angiography.Methods Two hundred and thirty-two patients[body mass index (BMI):23-25 kg/m2, with stable HR, and average HR ≥91 bpm]with suspected or known coronary artery disease underwent retrospective ECG-gated DSCT coronary angiography.They were divided into 3 groups (A-C) according to the average HR of scanning.Images were reconstructed from 29% to 80% of the R-R interval in 3% increments.Two independent readers assessed the overall image quality by a five-point scale and determined the optimal reconstruction windows of each coronary segment and the ranges.Coronary arteries were segmented according to the guideline of the American Heart Association (AHA).The degree of interobserver agreement was determined by Kappa statistics.Results Three thousand three hundred and fortythree segments were considered to have diagnostic image quality in 232 patients.The ranges of optimal reconstruction windows of images were concentrated on 81%-61% and 51%-31%.In group A(91-95 bpm), there were 1183 segments in 83 patients, and the according proportions were 5.49%, 94.51%,respectively; In group B(96-100 bpm), there were 986 segments in 68 patients, and the according proportions were 0.20%, 99.80%, respectively; In group C(≥ 101 bpm), there were 1174 segments in 81 patients, and the according proportions were 0.17%, 99.83%, respectively.The optimal construction windows in 3274 segments out of 3343 segments in 232 patients were concentrated in 41%, ranged from 51%-31%.The image quality assessment in 3343 segments in 232 patients have a high inter-observe agreement (Kappa=0.883,P <0.05).Conclusion The optimal reconstruction windows of patients with stable HR(≥91 bpm) was concentrated in 41%, ranged from 51%-31%.When nothing except the window of data acquisition is considered, the prospective ECC,-gated DSCT coronary angingraphy can be used in patients with stable HR(≥91 bpm).     

Diagnostic accuracy of dual-source CT coronary angiography with prospective ECG-triggering on different heart rate patients

Objective

To evaluate the diagnostic accuracy of dual-source CT (DSCT) prospective ECG-triggering coronary angiography in patients with different heart rate (HR).

Methods

103 patients with suspected coronary artery disease underwent DSCT prospective ECG-triggered coronary angiography and invasive coronary angiography (ICA). The patients were grouped by HR during CT scans: low HR (??60?bpm, n?=?34); medium HR (60?n?=?36) and high HR (>70?bpm, n?=?33). The sensitivity and specificity of DSCT in detecting ??50% stenosis were compared among subgroups where ICA was the gold standard. Image quality was scored using a 4-point scale.

Results

A total of 1,580 (95.9%) coronary artery segments were evaluable. Sensitivity and specificity were 82.8% and 98.4%, 88.3% and 98.7%, and 80.3% and 98.6% for different subgroups (all p?>?0.05). The overall area under the curve of the receiver-operating characteristic analysis was 0.94. The image quality scores were 3.1?±?0.3, 3.1?±?0.3 and 3.0?±?0.4 for subgroups (p?>?0.05). The overall average effective radiation dose was 3.60?±?1.60?mSv.

Conclusion

DSCT coronary angiography with prospective ECG-triggering could be just as accurate in patients with medium to high HR compared to those with low HR.     

前瞻性心电门控双源CT冠状动脉成像在高心率患者中应用的可行性研究

目的 探讨心率不低于91次/分(bpm)患者回顾性心电门控双源CT(DSCT)冠状动脉成像R-R间期的最佳重建时相,从扫描时相选择的角度分析前瞻性心电门控(简称前门控)应用的可行性.方法 分析232例行回顾性心电门控DSCT冠状动脉成像患者(体质量指数23～25 kg/m2,心率≥91 bpm)的图像,根据扫描过程中患者屏气时心电监控记录到的心率将其分为3组(A～C组),A组83例,心率91～95 bpm,B组68例,心率96～100 bpm,C组81例,心率≥101 bpm.每隔3%重建1个时相,分别由2名医师独立对横断面图像、薄层MIP、CPR、VRT图像质量采用5分法进行综合评估,按照15段分段法,选出每个节段的R-R间期的最佳重建时相及范围.采用Kappa检验,评价2名医师对冠状动脉图像评分的一致性.结果 232例患者中,可评价冠状动脉节段共3343个,其图像最佳重建时相范围集中在81%～61%和51%～31%.3组冠状动脉节段与之相对应的节段数百分比:A组(91～95 bpm,83例的1183个节段)分别为5.49%、94.51%;B组(96-100 bpm,68例986个节段)分别为0.20%、99.80%;C组(≥101 bpm,81例1174个节段)分别为0.17%、99.83%.232例患者的3343个冠状动脉节段中3274个节段(97.94%)最佳重建时相范围集中在以41%为中心的51%～31%R-R间期范围内.2名医师对232例患者的3343个冠状动脉节段图像质量的评分结果得到了较高的一致性(Kappa值=0.883,P<0.05).结论 具有稳定的窦性心律,且屏气时平均心率≥91 bpm患者,冠状动脉节段的最佳重建时相集中于以R-R间期41%为中心的51%～31%,从扫描时相选择的角度考虑,可以对稳定高心率(≥91 bpm)患者行前门控横断面扫描,并且预设41%为曝光时间窗,成功把握较大.     

双源CT冠状动脉成像的图像质量及重组时相与心率的关系

目的 探讨双源CT冠状动脉成像的图像质量和重组时相与心率的关系.方法 对95例临床可疑冠心病患者进行双源CT增强扫描,检查前均不使用β受体阻滞剂控制心率.按扫描时心率分为3组:低心率组(≤70 次/min)26例,中心率组(71～90 次/min)37例,高心率组(t≥91 次/min)32例.利用回顾性心电门控重建出10%～100% R-R时相的图像,分析不同R-R时相冠状动脉的图像质量情况及其与心率的关系.结果 低、中、高心率3组图像质量评分分别为(1.08±0.27)、(1.32±0.58)、(1.47±0.61)分,低心率和中心率组图像质量评分差异无统计学意义(P＞0.05),低心率组图像质量评分显著优于高心率组(P＜0.05),中心率组和高心率组图像质量评分差异无统计学意义(P＞0.05).只有1.4%(19/1386)的冠状动脉节段不可评价.74例患者(77.9%)可在单一重组时相获得冠状动脉各段最佳图像质量.低心率组23例(88.5%)最佳重组时相在舒张中晚期;高心率组27例(84.4%)的最佳重组时相前移至舒张早期和收缩末期.结论 双源CT能够在相当宽的心率范围内提供优良的图像质量;多数患者可在单一时相获得各支冠状动脉最佳质量图像,随着心率的增快最佳重组时相从舒张中晚期前移至舒张早期和收缩末期.     

双源CT前瞻性心电门控扫描在急性胸痛诊断中的临床应用

目的 探讨双源CT(DSCT)前瞻性心电门控扫描在急性胸痛诊断中的临床应用,并比较前瞻性心电门控与回顾性心电门控2种扫描技术的图像质量和辐射剂量.方法 连续搜集30例[A组,平均心率≥85次/min(bpm)]临床症状表现为急性胸痛并行DSCT前瞻性心电门控心胸联合血管成像的患者,连续搜集30例(B组,所有患者平均心率≥85 bpm)表现为急性胸痛行DSCT回顾性心电门控扫描的患者.对2组患者的冠状动脉、肺动脉及主动脉分别进行靶重组,评价2组图像质量,并对疾病进行诊断;应用x2检验和两独立样本t检验比较2组患者的图像质量和有效剂量.结果 A、B组可评价冠状动脉节段比例分别为98.44%(379/385)和98.48%(390/396),差异无统计学意义(x2=0.002,P=0.961);A、B组间图像噪声[分别为(16.23±5.75)、(16.31±3.32)HU]、信噪比(分别为26.85±9.94、24.78±9.91)及对比度噪声比(分别为20.99±9.31、18.65±8.72)差异均无统计学意义(t值分别为0.069、0.908、1.224,P值均＞0.05);A、B 2组有效剂量分别为(8.37±2.69)和(20.05±5.52)mSv,差异有统计学意义(t=9.401,P=0.000).结论 DSCT前瞻性心电门控心胸联合血管成像可以获得与回顾性心电门控扫描相似的图像质量,且辐射剂量降低.

Abstract：

Objective To evaluate the application of prospective ECG-gated dual source CT (DSCT) in patients with acute chest pain, and compare it's image quality and radiation dose with those of retrospective ECG-gated spiral scan. Methods Thirty consecutive patients (Group A, average HR ≥85 bpm) with acute chest pain were scanned with prospective ECG-gated scan and another 30 consecutive patients (Group B, average HR ≥85 bpm)were analyzed by retrospective ECG-gated scan. Tube voltage and tube current were adapted by the BMI of patients. MPR, MIP, CPR and VR were used to display pulmonary arteries (PA), thoracic aorta and coronary arteries (CA). Image quality as well as radiation dose were assessed in 2 groups. Qualitative image quality was compared with chi-square test between the two groups,while quantitative image quality [the image noise ( IN ), signal-to-noise ratio ( SNR ) and contrast-to-noise ratio(CNR)] and radiation dose were evaluated with x2 test and Student's t test. Results The proportion of valid coronary segments for diagnosis were 379/385 ( 98. 44% ) and 390/396 ( 98.48% ) respectively in Group A and Group B with no significant difference(x2 =0. 002,P =0. 961 ). The IN [( 16. 23 ±5.75)vs ( 16. 31 ±3. 32) HU] ,SNR (26. 85 ±9. 94 vs 24. 78 ±9. 91 ) and CNR (20. 99 ±9. 31 vs 18. 65 ±8. 72)showed no significant differences between 2 groups ( t = 0. 069,0. 908 and 1. 224, P ＞ 0. 05, respectively).The ED was on average ( 8. 37 ± 2. 69 ) mSv in Group A, whereas on average ( 20. 05 ± 5.52 ) mSv in Group B. There was a statistical difference between 2 groups ( t = 9. 401, P = 0. 000). Conclusion Low dose prospective ECG-gated DSCT angiography can show similar image quality as retrospective ECG-gated spiral scan with radiation dose.     

平均心率、心率波动和心率变异性对双源CT冠状动脉影像质量影响的研究

目的：评价平均心率、心率波动和心率变异性对双源CT冠状动脉影像质量的影响。方法：100例患者进行了双源CT冠状动脉血管成像。原始数据经多期相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。利用Pearson相关分析评价平均心率、心率波动和心率变异性对冠状动脉的影像质量的影响,对有相关性者行进一步分析。结果：100例患者,共纳入分析的血管为299支,296支血管可满足影像评价（99％）。平均心率、心率波动和心率变异性对总的冠状动脉影像质量没有影响,仅平均心率对舒张期冠状动脉影像质量有负影响（P〉0．05）,尤其对右冠状动脉的影响更明显,70bpm以上时影像质量即下降,80bpm以上时影像质量甚至难以满足评价。结论：平均心率、心率波动和心率变异性对双源cr冠状动脉总的影像质量没有影响,但平均心率对舒张期冠状动脉的影像质量有负影响,对右冠状动脉的影响更大,当心率大于80bpm时,利用舒张期的数据难以获得RCA满意的影像质量,应该利用最佳收缩期的数据进行影像重组。     

双源CT冠状动脉成像在早搏患者中应用的初步体会

目的 探讨应用双源CT对早搏患者进行冠状动脉成像的可行性.方法 对70例临床可疑冠心病的早搏患者进行双源CT增强扫描.利用回顾性心电门控重建心电图编辑前后的图像,以4级记分评价图像质量.比较心电图编辑前后的图像质量采用配对t检验.结果 70例中28例患者的心率波动范围较小[(41.0±18.4)次/min],无需心电图编辑可获得诊断级图像;其余42例患者的心率波动范围较大[(71.4±28.7)次/min],心电图编辑前后的冠状动脉图像质量评分分别为(2.09±1.27)和(1.50±0.79)分,差异有统计学意义(t=13.764,P＜0.01);不可评价的冠状动脉节段比例从24.8%(154/620)降至3.4%(21/620).差异有统计学意义(X2=121.846,P＜0.01).70例患者98.0%(1014/1035)的冠状动脉节段可以评价.结论 拥有高时间分辨率的双源CT能够为早搏患者提供可评价的图像;对于心率波动范围大的患者,心电图编辑能够显著改善图像质量.     

双源CT低剂量前瞻性心电触发序列扫描在冠状动脉血管成像的应用

目的 研究双源CT低剂量前瞻性心电触发序列扫描技术在冠状动脉CTA的应用,并评价其图像质量.方法 将68例行冠状动脉CTA检查的患者分为2组,A组38例行前瞻性心电触发序列扫描,入组标准为心率70次/min(bpm)以下,窦性心律,心率波动范围在10 bpm以内.排除标准为心率不能控制在70 bpm以内及心律不齐患者、屏气不佳者以及冠状动脉存在严重钙化及明显狭窄者.采集期相70%R-R间期.B组30例为常规回顾性心电门控螺旋扫描,人组标准为心率70 bpm以下,窦性心律且规整.排除标准为心律不齐患者、屏气不佳者以及冠状动脉存在严重钙化及明显狭窄者.2组中管电压均随体质量指数(BMI)调整,BMI≥24 ks/m2管电压采用120 kV,BMI<24 ks/m2管电压采用100 kV.对2组扫描的冠状动脉分别做图像处理,应用秩和检验比较2组患者冠状动脉段图像质量评分,应用两独立样本t检验比较2组患者辐射剂量.结果 A组评价476段冠状动脉,B组评价372段冠状动脉.A组冠状动脉段图像质量评分为(3.48±0.59)分,B组均值为(3.53±0.58)分,2组之间比较差异无统计学意义(Z=-1.432,P=0.187).A组平均有效剂量为(2.51±0.54)mSv;B组平均有效剂量为(14.55±3.54)mSv,2组之间平均有效剂量比较差异有统计学意义(t=18.484,P=0.000).结论 在严格掌握心率及心律的基础上,可成功实现前瞻性触发序列扫描,该技术能显著降低辐射剂量而保证诊断所需图像质量.     

Image quality and reconstruction intervals of dual-source CT coronary angiography: recommendations for ECG-pulsing windowing

PURPOSE: To evaluate reconstruction intervals and image quality in dual-source computed tomography (DSCT) coronary angiography for optimal placement of the ECG-pulsing window. MATERIALS AND METHODS: DSCT coronary angiography was performed in 60 patients. Thirteen datasets were reconstructed in 5% increments from 20-80%. Two readers independently assessed image quality of each segment in each percentage-interval, using scores ranging from 1 (no motion artifacts) to 4 (nonevaluable). RESULTS: Mean heart rate (HR) was 69.0 +/- 18.9 beats per minute (bpm) (range, 35-117 bpm). Diagnostic image quality (scores 1-3) was found in 97.8% of all segments (763 of 780). The 70% RR-interval provided best image quality in all patients and all HRs. The narrowest reconstruction window providing diagnostic image quality was 60-70% for HR <60 bpm, 60-80% for 60-70 bpm, 55-80% for 70-80 bpm, and 30-80% for HR >80 bpm. CONCLUSIONS: DSCT coronary angiography provides best image quality for various HRs at 70%. The ECG-pulsing window can be adapted according to the HR while maintaining diagnostic image quality.     

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.     

Accuracy of dual-source CT coronary angiography: first experience in a high pre-test probability population without heart rate control

The aim of this study was to assess the diagnostic accuracy of dual-source computed tomography (DSCT) for evaluation of coronary artery disease (CAD) in a population with extensive coronary calcifications without heart rate control. Thirty patients (24 male, 6 female, mean age 63.1±11.3 years) with a high pre-test probability of CAD underwent DSCT coronary angiography and invasive coronary angiography (ICA) within 14±9 days. No beta-blockers were administered prior to the scan. Two readers independently assessed image quality of all coronary segments with a diameter ≥1.5 mm using a four-point score (1: excellent to 4: not assessable) and qualitatively assessed significant stenoses as narrowing of the luminal diameter >50%. Causes of false-positive (FP) and false-negative (FN) ratings were assigned to calcifications or motion artifacts. ICA was considered the standard of reference. Mean body mass index was 28.3±3.9 kg/m² (range 22.4–36.3 kg/m²), mean heart rate during CT was 70.3±14.2 bpm (range 47–102 bpm), and mean Agatston score was 821±904 (range 0–3,110). Image quality was diagnostic (scores 1–3) in 98.6% (414/420) of segments (mean image quality score 1.68±0.75); six segments in three patients were considered not assessable (1.4%). DSCT correctly identified 54 of 56 significant coronary stenoses. Severe calcifications accounted for false ratings in nine segments (eight FP/one FN) and motion artifacts in two segments (one FP/one FN). Overall sensitivity, specificity, positive and negative predictive value for evaluating CAD were 96.4, 97.5, 85.7, and 99.4%, respectively. First experience indicates that DSCT coronary angiography provides high diagnostic accuracy for assessment of CAD in a high pre-test probability population with extensive coronary calcifications and without heart rate control.