2.Dual-source variable pitch spiral CT reconstruction algorithm.
Jun ZHAO ; Zungang LIU ; Yannan JIN ; Tiange ZHUANG
Journal of Biomedical Engineering 2008;25(6):1249-1253
Computed tomography angiography (CTA) is a useful approach for diagnosing vascular diseases. In this paper, we proposed a reconstruction algorithm for dual-source spiral CT with variable pitch. The projection data are collected by the double-source double-multislice spiral CT (DSDMS-CT). However, the pitch of the DSDMS-CT is variable other than being constant. We have developed a new formula performing interpolation along Z-axis for dual-source spiral CT with variable pitch. The dual-source spiral CT with variable pitch can chase contrast bolus more flexibly and more effectively. The simulation results show the correctness and efficiency of the proposed algorithm.
Algorithms
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Coronary Angiography
;
methods
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Humans
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Tomography, Spiral Computed
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instrumentation
;
methods
3.Accuracy of Two-Dimensional Speckle Tracking Echocardiography for the Detection of Significant Coronary Stenosis.
Journal of Cardiovascular Ultrasound 2013;21(4):177-182
BACKGROUND: Visual assessment of wall motion abnormalities (WMA) by 2-dimensional echocardiography (2DE) is the most semi-quantitative method used to detect coronary artery disease (CAD), but it carries many limitations. Speckle tracking echocardiography (STE) overcomes these limitations and allows an objective quantification of myocardial deformation. The aim of the study to examine the accuracy of global and segmental longitudinal strain (LS) for the detection of CAD compared with visual assessment of WMA using coronary angiography as a golden standard. METHODS: The study enrolled 25 patients (mean age 51.0 +/- 8.7, 64% are male) referred to coronary angiography with clinical suspicion of CAD. 2DE assessment of WMA and evaluation of LS using STE were performed using left ventricular 17-segments models. Significant CAD was defined as > or = 50% stenosis in one or more major coronary arteries by angiography. RESULTS: Patients were classified into 2 groups: group I included 15 patients with significant CAD and group II included 10 patients with insignificant and/or absence of CAD. WM score was strongly correlated with the global LS in group I and II (R = 0.80, p < 0.0001 and R = 0.88, p < 0.0001 respectively). In all patients, 425 segments were analyzed. WMA was detected in 163 segments of 425 (38.3%) while abnormal LS was detected in 214 segments (50.3%). Compared with coronary angiography, the total sensitivity, specificity and accuracy for visual analysis and STE were (56%, 88.2%, and 60% vs. 68.6%, 77%, and 81.8% respectively). CONCLUSION: Segmental LS is more accurate for the detection of ischemic myocardial segment corresponding to functionally relevant coronary anatomy than visual assessment of WM.
Angiography
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Constriction, Pathologic
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Coronary Angiography
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Coronary Artery Disease
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Coronary Stenosis*
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Coronary Vessels
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Echocardiography*
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Humans
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Methods
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Sensitivity and Specificity
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Track and Field*
4.Modified Subtraction Coronary CT Angiography with a Two-Breathhold Technique: Image Quality and Diagnostic Accuracy in Patients with Coronary Calcifications
Weifeng GUO ; Pratik TRIPATHI ; Shan YANG ; Juying QIAN ; Bimal RAI ; Mengsu ZENG
Korean Journal of Radiology 2019;20(7):1146-1155
OBJECTIVE: To evaluate a modified subtraction coronary computed tomography angiography (CCTA) technique with a two-breathhold approach in terms of image quality and stenosis grading of calcified coronary segments and in the detection of significant coronary stenosis in segments with severe calcification. MATERIALS AND METHODS: The institutional board approved this study, and all subjects provided written consent. A total of 128 patients were recruited into this trial, of which 32 underwent subtraction CCTA scans and invasive coronary angiography (ICA). The average Agatston score was 356 ± 145. In severely calcified coronary segments, the presence of significant (> 50%) stenosis was assessed on both conventional CCTA and subtraction CCTA images, and the results were finally compared with ICA findings as the gold standard. RESULTS: For severely calcified segments, the image quality in conventional CCTA significantly improved from 2.51 ± 0.98 to 3.12 ± 0.94 in subtraction CCTA (p < 0.001). In target segments, specificity (70% vs. 87%; p = 0.005) and positive predictive value (61% vs. 79%, p < 0.01) were improved using subtraction CCTA in comparison with conventional CCTA, with no loss in the negative predictive value. The segment-based diagnostic accuracy for detecting significant stenosis was significantly better in subtraction CCTA than in conventional CCTA (area under the receiver operating characteristic curve, 0.94 vs. 0.85; p = 0.03). CONCLUSION: This modified subtraction CCTA method showed lower misregistration and better image quality in patients with limited breathhold capability. In comparison with conventional CCTA, modified subtraction CCTA would allow stenosis regrading and improve the diagnostic accuracy in coronary segments with severe calcification.
Angiography
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Constriction, Pathologic
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Coronary Angiography
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Coronary Stenosis
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Humans
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Methods
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ROC Curve
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Sensitivity and Specificity
5.Current and future roles of multi-slice spiral computed tomography in noninvasive imaging of coronary arteries.
Lan SONG ; Zhu-hua ZHANG ; Zheng-yu JIN
Acta Academiae Medicinae Sinicae 2006;28(1):110-114
The emergence of multi-slice spiral computed tomography (MSCT) has a significant influence on cardiovascular imaging. As a noninvasive technique, MSCT is considered suitable for the evaluation of coronary artery stenosis, quantitative and qualitative assessment of plaque, analysis of cardiac function and myocardial perfusion imaging, and determination of the patency of stents or bypass grafts. Recent studies has shown that noninvasive coronary artery imaging with MSCT is a feasible screening test for suspected coronary artery diseases and a valuable follow-up tool for patients who have undergone interventional or surgical therapeutic procedures.
Coronary Angiography
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methods
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Coronary Artery Disease
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diagnostic imaging
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Coronary Stenosis
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diagnostic imaging
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Humans
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Tomography, Spiral Computed
6.A meta-analysis of randomized controlled trials comparing left with right radial approach for coronary angiography.
Xiaowei NIU ; Cuiling YANG ; Shengliang HE ; De CHEN ; Dong YAN ; Zhiyu HE ; Yali YAO
Chinese Journal of Cardiology 2014;42(3):241-246
OBJECTIVETo compare the efficacy between left radial approach (LRA) and right radial approach (RRA) for coronary angiography (CAG).
METHODSThe following databases were searched, including PubMed, Embase, Web of science, Cochrane Library, CBM, VIP, Wanfang databases and CNKI, from creation of database to January 2013. Two reviewers extracted data independently, according to inclusive criteria, exclusion criteria and methods of Cochrane Collaboration. Statistical analysis was performed using Review Manager Software (RevMan 5.1).
RESULTSEleven trials with 5 442 patients were included in the systematic review. The results of meta-analysis showed that when compared with RRA, LRA did not increase the failure rate of the procedures (OR = 1.04, 95%CI 0.80-1.35, P > 0.05) and amount of contrast medium (mean difference = 2.39, 95%CI -0.30-5.08), P > 0.05). However, LRA was superior to RRA in reducing fluoroscopy time (standardized mean difference = 0.15, 95%CI 0.06-0.24, P < 0.01). In addition, the incidence of severe tortuosity of subclavian artery was significantly lower with LRA (OR = 4.65, 95%CI 1.98-10.88, P < 0.01).
CONCLUSIONSBased on the current evidence, LRA shares similar safety with RRA for CAG and is superior to RRA in certain respects. LRA can thus be used either as an alternative approach or routine approach for CAG.
Coronary Angiography ; methods ; Humans ; Radial Artery ; Randomized Controlled Trials as Topic
7.An approach for segmentation of X-ray angiographic image based on region-growing and structure inferring.
Chuan MEI ; Guiliang WU ; Yuan YANG ; Lan XIE ; Jiaju HE ; Shaolin LI ; Shoujun ZHOU
Journal of Biomedical Engineering 2014;31(2):413-420
We presented a new method for vessel segmentation and vascular structure recognition for coronary angiographic images. During vessel segmentation, a new vessel function was proposed to attain vessel feature map. Then the region growing algorithm was implemented with an automatic selection of seed point, extraction of main vessel branch, and vessel detail repairing. In the algorithm of vascular structure recognition, a fuzzy operator was used, which can detect the structures of vascular segments, bifurcations, crosses, and tips. The experimental results indicated that there was about 5 percent larger vessel region which was extracted by the proposed segmentation method than that by the simple region growing algorithm, and several thinner vessels were resumed from the lower gray region. The results also indicated that the fuzzy operator could correctly infer the simulative and real vessel structure with 100% and 90.59% correctness rate on the average, respectively.
Algorithms
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Coronary Angiography
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Humans
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Radiographic Image Enhancement
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methods
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X-Rays
9.Higenamine as a Potential Pharmacologic Stress Agent in the Detection of Coronary Artery Disease.
Na-Na ZHANG ; Zi-Jian LI ; Hai-Bo ZHU
Chinese Medical Sciences Journal 2022;37(3):275-281
Myocardial perfusion imaging (MPI) is valuable for the diagnosis, prognosis, and management of coronary artery disease (CAD). The most commonly used pharmacologic stress agents at present are vasodilators and adrenergic agents. However, these agents have contraindications and may cause adverse effects in some patients. Thus, other stress agents feasible for more patients are required. Higenamine (HG) is a β-adrenergic receptor agonist currently approved for clinical trials as a stress agent for myocardial infarction. It also has a promising value in MPI for the detection of CAD in preclinical and clinical studies. This review summarizes the application of HG on MPI, including its mechanism of action, stress protocol, efficacy, and safety.
Humans
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Coronary Artery Disease
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Myocardial Perfusion Imaging/methods*
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Tetrahydroisoquinolines
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Alkaloids
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Coronary Angiography/methods*
10.Coronary artery motion estimation using X-ray cineangiogram.
Zheng SUN ; Daoyin YU ; Jiaxiang HUANG ; Zhi XU
Journal of Biomedical Engineering 2005;22(4):690-694
This paper presents an approach for estimating the non-rigid motion of coronary arteries using digital angiographic images. Displacement vectors of vessel points are obtained by finding points correspondences in two successive frames. Smoothness of motion field and vessel deformation measurement are considered in matching, and unmatched regions are also dealt with in the fact that the vessel after deformation may have different size with its original station. The search strategy for optimal matching is carried out using dynamic programming (DP) so that computing cost is reduced. Results of this motion estimation method applied to synthetic and clinical images have shown that the method is accurate, with a root mean square error about one pixel for simulated data. For the case of actual X-ray coronary angiographic images, visual inspection of the detected pairs of points shows that the results are very encouraging.
Angiography, Digital Subtraction
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methods
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Coronary Angiography
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methods
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Coronary Vessels
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physiology
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Humans
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Movement
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Radiographic Image Interpretation, Computer-Assisted