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冠状动脉造影图像降噪处理的3种方法比较 被引量:1
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作者 马振鹤 万柏坤 +1 位作者 王瑞平 谢远国 《生物医学工程与临床》 CAS 2002年第3期129-131,共3页
目的 对冠状动脉造影图像降噪处理的 3种方法进行比较。方法 将冠状动脉造影图像数字化并输入计算机 ,然后再用中值滤波法、自适应滤波法和基于小波变换的降噪处理 3种方法分别处理同一图像 ,比较效果。结果 成功地运用了 3种方法对... 目的 对冠状动脉造影图像降噪处理的 3种方法进行比较。方法 将冠状动脉造影图像数字化并输入计算机 ,然后再用中值滤波法、自适应滤波法和基于小波变换的降噪处理 3种方法分别处理同一图像 ,比较效果。结果 成功地运用了 3种方法对冠状动脉造影图像进行降噪处理 ,图像质量均有所提高。结论 自适应降噪处理和基于小波系数的降噪处理结果较好 。 展开更多
关键词 冠状动脉造影图像 降噪处理 中值滤波 自适应滤波 小波变换
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基于多监督残差网络的冠状动脉CT图像分割 被引量:2
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作者 顾峰 曹秒 +2 位作者 蔡庆武 董麒 张坤 《长春理工大学学报(自然科学版)》 2022年第5期101-106,共6页
冠状动脉血管造影图像是医生诊断心血管疾病的主要依据,对冠状动脉进行准确地分割在心血管疾病诊断具有重要意义。人工分割血管是一个费时费力的过程,容易出现主观性和误判性。因此,提出一种自动、准确的血管分割系统,称为多监督残差网... 冠状动脉血管造影图像是医生诊断心血管疾病的主要依据,对冠状动脉进行准确地分割在心血管疾病诊断具有重要意义。人工分割血管是一个费时费力的过程,容易出现主观性和误判性。因此,提出一种自动、准确的血管分割系统,称为多监督残差网络(MSRNet)。在残差网络中增加了三个有监督的侧输出模块,并将输出的特征图进行融合,得到最终的分割结果。将MSRNet在测试集上的准确率为0.925。MSRNet的分割精度相比U-Net和ResNet最高,最接近人类专家手动分割的结果。MSRNet可以减少诊断过程中的人工交互以及对医务人员的依赖,提高了疾病诊断效率。 展开更多
关键词 冠状动脉造影图像 血管分割 深度学习 迁移学习
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基于冠脉造影图像血管树分割的血管狭窄自动识别方法 被引量:2
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作者 陈建辉 赵蕾 +1 位作者 李德玉 万涛 《中国生物医学工程学报》 CAS CSCD 北大核心 2019年第3期266-272,共7页
针对冠状动脉造影图像中的血管狭窄位置进行自动识别,并且定量评估其狭窄程度,为临床医生提供一种计算机辅助诊断方法,从而提高对冠状动脉狭窄的诊断准确率,同时减轻医生的劳动强度。所提出的基于冠脉造影图像的血管狭窄自动识别方法包... 针对冠状动脉造影图像中的血管狭窄位置进行自动识别,并且定量评估其狭窄程度,为临床医生提供一种计算机辅助诊断方法,从而提高对冠状动脉狭窄的诊断准确率,同时减轻医生的劳动强度。所提出的基于冠脉造影图像的血管狭窄自动识别方法包括血管树分割以及血管狭窄识别两部分。在血管树分割部分,首先通过基于Frangi Hessian的改进模型进行图像增强,随后利用基于统计学区域融合方法对血管区域进行分割。在血管狭窄识别部分,首先利用水平集算法对分割结果进行细化获得血管骨架,随后提取血管边缘进行血管直径测量,最后采用局部最小点法计算整幅图像血管段狭窄的百分比,对狭窄段进行定位并分级。实验在153例患者的血管造影图像中检测出狭窄共计208段,其中轻度84段,中度42段,重度82段。统计分析结果显示,血管狭窄识别平均准确率为93.59%,敏感性为88.76%,特异性为95.58%,阳性预测值为90.51%,表明该方法能够有效地检测和定量评价动脉血管的狭窄程度,有助于心血管疾病的临床诊断。 展开更多
关键词 血管狭窄评估 冠状动脉造影图像 血管树分割 血管直径测量
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Feasibility and Diagnostic Accuracy for Assessment of Coronary Artery Stenosis of Prospectively Electrocardiogram-gated High-pitch Spiral Acquisition Mode Dual-source CT Coronary Angiography in Patients with Relatively Higher Heart Rates: in Comparison wit 被引量:4
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作者 Kai Sun Rui-juan Han +5 位作者 Li-fang Cui Rui-ping Zhao Li-jun Ma Li-jun Wang Li-gang Li Chang-yong Li 《Chinese Medical Sciences Journal》 CAS CSCD 2012年第4期213-219,共7页
Objective To prospectively investigate the diagnostic accuracy for coronary artery stenosis of prospectively electrocardiogram-triggered spiral acquisition mode (high pitch mode) dual-source computed tomography corona... Objective To prospectively investigate the diagnostic accuracy for coronary artery stenosis of prospectively electrocardiogram-triggered spiral acquisition mode (high pitch mode) dual-source computed tomography coronary angiography (CTCA) in patients with relatively higher heart rates (HR) compared with catheter coronary angiography (CCA). Methods Forty-seven consecutive patients with relatively higher HR (>65 and <100 bpm) (20 male, 27 female; age 55±10 years) who both underwent dual-source CTCA and CCA were prospectively included in this study. All patients were performed CTCA using high pitch mode setting at 20%-30% of the R-R interval for the image acquisition. All coronary segments were evaluated by two blinded and independent observers with regard to image quality on a three-point scale (1: excellent to 3: non-diagnostic) and for the presence of significant coronary stenoses (defined as diameter narrowing exceeding 50%). Considered CCA as the standard of reference, the sensitivity, specificity, positive predictive value and negative predictive value were calculated. Radiation dose values were calculated using the dose-length product. Results Image quality was rated as being score 1 in 92.4% of segments, score 2 in 6.1% of segmentsand score 3 in 1.5% of segments. The average image quality score per segment was 1.064±0.306. The HR variability of patients with image score 1, 2 and 3 were 2.29±1.06 bpm, 5.17±1.37 bpm, 8.88±1.53 bpm, respectively. The average HR variability of patients with different image scores were significantly different (F=170.402, P=0.001). The sensitivity, specificity, positive and negative predictive values were 92.6%, 97.0%, 87.6%, 98.3%, respectively, per segment and 90.0%, 95.2%, 85.3%, 96.9%, respectively, per vessel and 100%, 63.6%, 90.0%, 100%, respectively, per patient. The effective radiation dose was on average 0.86±0.16 mSv. Conclusion In patients with HR more than 65 bpm and below 100 bpm without cardiac arrhythmia, the prospectively electrocardiogram-gated high-pitch spiral acquisition mode with image acquired timing set at 20%-30% of the R-R interval provides a high diagnostic accuracy for the assessment of coronary stenoses combined with a 1.5% of non-diagnostic coronary segments and a radiation dose below 1 mSv. 展开更多
关键词 dual-source computed tomography coronary angiography high pitch prospectively electrocardiogram-triggered spiral mode high heart rate diagnostic accuracy
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Performance of dual-source CT with high pitch spiral mode for coronary stent patency compared with invasive coronary angiography 被引量:10
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作者 Xia YANG Qiang YU +4 位作者 Wei DONG Zhen-Hong FU Jun-Jue YANG Jun GUO Yun-Dai CHEN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第10期817-823,共7页
Objective To investigate the performance of dual-source computed tomography (DSCT) using high-pitch spiral fliPS) mode for coronary stents patency. Methods We conducted a prospective study on 120 patients with 260 ... Objective To investigate the performance of dual-source computed tomography (DSCT) using high-pitch spiral fliPS) mode for coronary stents patency. Methods We conducted a prospective study on 120 patients with 260 previous stents implanted due to recurred suspicious symptoms of angina scheduled for invasive coronary angiography (ICA), while DSCT were conducted using HPS mode. Results There was no significant impact of age, body mass index or heat rate (HR) on image quality (P 〉 0.05), while HR variability had a slight impact on that (P 〈 0.05). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) of DSCT in detection of in-stent restenosis (ISR) based per-patient were 92.3%, 96.7%, 88.9%, and 97.8%, respectively. And those based per-stent were 87%, 96.8%, 83.3%, and 97.7% with un-assessment stents, 97.4%, 99.5%, 97.4%, and 99.5% without un-assessment stents. There was significant differ- ence on sensitivity, specificity, PPV and NPV between diameter 〉 3.0 mm group (93.3%, 97.9%, 87.5%, and 98.9%) and diameter 〈 3.0 mm group (80%, 93.3%, 80.0%, and 93.3%) (P 〈 0.05), and that between stent number 〉 3 group (82.3%, 77.8%, 66.7%, and 60%) with 〈 3 group (97.3%, 80%, 96.5%, and 75%). The effective dose of DSCT (1.4 ± 0.5 mSv) is significantly less than that by invasive coronary angiography [4.0 ± 0.8 mSv (P 〈 0.01)]. Conclusion DSCT using HPS mode provides good diagnostic performance on stent patency with lower effective dose in patients with HR 〈 65 beats/rain. 展开更多
关键词 Coronary angiography High-pitch spiral mode Percutaneous coronary intervention STENT
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128-slice Dual-source Computed Tomography Coronary Angiography in Patients with Atrial Fibrillation: Image Quality and Radiation Dose of Prospectively Electrocardiogram-triggered Sequential Scan Compared with Retrospectively Electrocardiogram-gated Spiral
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作者 Lu Lin Yi-ning Wang +9 位作者 Ling-yan Kong Zheng-yu Jin Guang-ming Lu Zhao-qi Zhang Jian Cao Shuo Li Lan Song Zhi-wei Wang Kang Zhou Ming Wang 《Chinese Medical Sciences Journal》 CAS CSCD 2012年第4期195-200,共6页
Objective To evaluate the image quality (IQ) and radiation dose of 128-slice dual-source computed tomography (DSCT) coronary angiography using prospectively electrocardiogram (ECG)-triggered sequen- tial scan mo... Objective To evaluate the image quality (IQ) and radiation dose of 128-slice dual-source computed tomography (DSCT) coronary angiography using prospectively electrocardiogram (ECG)-triggered sequen- tial scan mode compared with ECG-gated spiral scan mode in a population with atrial fibrillation. Methods Thirty-two patients with suspected coronary artery disease and permanent atrial fibrilla- tion referred for a second-generation 128-slice DSCT coronary angiography were included in the prospec- tive study. Of them, 17 patients (sequential group) were randomly selected to use a prospectively ECG.~triggered sequential scan, while the other 15 patients (spiral group) used a retrospectively ECG-gated spiral scan. The IQ was assessed by two readers independently, using a four-point grading scale from excel- lent (grade 1) to non-assessable (grade 4), based on the American Heart Association 15-segment model. IQ of each segment and effective dose of each natient were comDared between the two groups. Results The mean heart rate (HR) of the sequential group was 96±27 beats per minute (bpm) with a variation range of 73±25 bpm, while the mean HR of the spiral group was 86±22 bpm with a variationrange of 65±24 bpm. Both of the mean FIR (t= 1.91, P=0.243) and HR variation range (t=0.950, P=0.350) had no significant difference between the two groups. In per-segment analysis, IQ of the sequential group vs. spiral group was rated as excellent (grade 1) in 190/244 (78%) vs. 177/217 (82%) by readerl and 197/245 (80%) vs. 174/214 (81%) by reader2, as non-assessable (grade 4) in 4/244 (2%) vs. 2/217 (1%) by readerl and 6/245 (2%) vs. 4/214 (2%) by reader2. Overall averaged IQ per-patient in the sequential and spiral group showed equally good (1.27+0.19 vs. 1.25+0.22, Z=-0.834, P=0.404). The effective radiation dose of the sequential group reduced significantly compared with the spiral group (4.88±1.77 mSv vs. 10.20±3.64 mSv; t=-5.372, P=0.000). Conclusion Compared with retrospectively ECG-gated spiral scan, prospectively ECG-triggered sequential DSCT coronary angiography provides similarly diagnostically valuable images in patients with atrial fibrillation and significantly reduces radiation dose. 展开更多
关键词 atrial fibrillation computed tomography coronary angiography prospectivelyelectrocardiogram-triggered sequential scan
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