51 research outputs found
Association between aortic supravalvular stenosis and coronary ectasia
No full textFil: De Zan, Macarena C. Diagnostico Maipu, Buenos Aires; ArgentinaFil: Carrascosa, Patricia. Diagnostico Maipu, Buenos Aires; ArgentinaFil: Deviggiano, Alejandro. Diagnostico Maipu, Buenos Aires; ArgentinaFil: Basara, Monica. Diagnostico Maipu, Buenos Aires; ArgentinaFil: Rodriguez Granillo, Gaston Alfredo. Diagnostico Maipu, Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Cardiológicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Cardiológicas; Argentin
Dual energy cardiac computed tomography
No full textConventional single energy CT suffers from technical limitations related to the polychromatic nature of X-rays. Dual energy cardiac CT (DE CT) shows promise to attenuate and even overcome some of these limitations, and might broaden the scope of patients eligible for cardiac CT towards the inclusion of higher risk patients. This might be achieved as a result of both safety (contrast reduction) and physiopathological (myocardial perfusion and characterization) issues. In this article, we will review the main clinical cardiac applications of DE CT, that can be summarized in two core aspects: coronary artery evaluation, and myocardial evaluation.Fil: Carrascosa, Patricia. Diagnostico Maipu, Buenos Aires; ArgentinaFil: Deviggiano, Alejandro. Diagnostico Maipu, Buenos Aires; ArgentinaFil: Rodriguez Granillo, Gaston Alfredo. Diagnostico Maipu, Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Dual energy imaging and intracycle motion correction for CT coronary angiography in patients with intermediate to high likelihood of coronary artery disease
No full textWe explored whether intracycle motion correction algorithms (MCAs) might be applicable to dual energy computed tomography coronary angiography in patients with intermediate to high likelihood of coronary artery disease. MCA reconstructions were associated with higher interpretability rates (96.7% vs 87.9%, P < .001), image quality scores (4.12±0.9 vs. 3.76±1.0; P < .0001), and diagnostic performance [area under the curve of 0.95 (95% confidence interval [CI] 0.92-0.97) vs 0.89 (95% CI 0.86-0.92); P < .0001] compared to conventional reconstructions. In conclusion, application of intracycle MCA reconstructions to dual energy computed tomography acquisitions was feasible and resulted in significantly higher image quality scores, interpretability, and diagnostic performance.Fil: Carrascosa, Patricia. Diagnóstico Maipú; ArgentinaFil: Deviggiano, Alejandro. Diagnóstico Maipú; ArgentinaFil: Leipsic, Jonathon A.. St. Paul's Hospital; CanadáFil: Capunay, Carlos. Diagnóstico Maipú; ArgentinaFil: De Zan, Macarena C.. Diagnóstico Maipú; ArgentinaFil: Goldsmit, Alejandro. Sanatorio Güemes; ArgentinaFil: Rodriguez Granillo, Gaston Alfredo. Diagnóstico Maipú; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Cardiológicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Cardiológicas; Argentin
Effect of Intracycle Motion Correction Algorithm on Image Quality and Diagnostic Performance of Computed Tomography Coronary Angiography in Patients with Suspected Coronary Artery Disease
No full textRationale and objectives: We sought to explore the impact of intracycle motion correction algorithms (MCA) in the interpretability and diagnostic accuracy of computed tomography coronary angiography (CTCA) performed in patients suspected of coronary artery disease (CAD) referred to invasive coronary angiography. Materials and Methods: Patients with suspected CAD referred to invasive coronary angiography previously underwent CTCA. Patients under rate-control medications were advised to withhold for the previous 24hours. The primary end point of the study was to evaluate image interpretability and diagnostic performance of MCA compared to conventional reconstructions in patients referred to invasive angiography because of suspected CAD. Results: Thirty-five patients were prospectively included in the study protocol. The mean age was 61.4±9.4years. Twenty-seven (77%) patients were men. A total of 533 coronary segments were evaluated using conventional and MCA reconstructions. MCA reconstructions were associated to higher interpretability rates (525 of 533, 98.5% vs. 515 of 533, 96.6 %; P<.001) and image quality scores (3.88±0.54 vs. 3.78±0.76; P<.0001) compared to conventional reconstructions. Although only mild, a significant difference was observed regarding the diagnostic performance between reconstruction modes, with an area under the curve of 0.90 (0.87-0.92) versus 0.89 (0.86-0.92), respectively, for MCA and conventional reconstructions (. P=.0447). Conclusions: In this pilot investigation, MCA reconstructions performed in patients with suspected CAD were associated to higher interpretability rates and image quality scores compared to conventional reconstructions, although only mild differences were observed regarding the diagnostic performance between reconstruction modes.Fil: Carrascosa, Patricia. Sanatorio Güemes; Argentina. Diagnóstico Maipú; ArgentinaFil: Deviggiano, Alejandro. Sanatorio Güemes; Argentina. Diagnóstico Maipú; ArgentinaFil: Capunay, Carlos. Sanatorio Güemes; Argentina. Diagnóstico Maipú; ArgentinaFil: De Zan, Macarena C.. Sanatorio Güemes; Argentina. Diagnóstico Maipú; ArgentinaFil: Goldsmit, Alejandro. Sanatorio Güemes; Argentina. Diagnóstico Maipú; ArgentinaFil: Rodriguez Granillo, Gaston Alfredo. Diagnóstico Maipú; Argentina. Sanatorio Güemes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Low-dose CT coronary angiography using iterative reconstruction with a 256-slice CT scanner
No full textAIM: To explore whether computer tomography coronary angiography (CTCA) using iterative reconstruction (IR) leads to significant radiation dose reduction without a significant loss in image interpretability compared to conventional filtered back projection (FBP).
METHODS: A consecutive series of 200 patients referred to our institution to undergo CTCA constituted the study population. Patients were sequentially assigned to FBP or IR. All studies were acquired with a 256-slice CT scanner. A coronary segment was considered interpretable if image quality was adequate for evaluation of coronary lesions in all segments ≥ 1.5 mm.
RESULTS: The mean age was 56.3 ± 9.6 years and 165 (83%) were male, with no significant differences between groups. Most scans were acquired using prospective ECG triggering, without differences between groups (FBP 84% vs IR 82%; P = 0.71). A total of 3198 (94%) coronary segments were deemed of diagnostic quality. The percent assessable coronary segments was similar between groups (FBP 91.7% ± 4.0% vs IR 92.5% ± 2.8%; P = 0.12). Radiation dose was significantly lower in the IR group (2.8 ± 1.4 mSv vs 4.6 ± 3.0 mSv; P < 0.0001). Image noise (37.8 ± 1.4 HU vs 38.2 ± 2.4 HU; P = 0.20) and signal density (461.7 ± 51.9 HU vs 462.2 ± 51.2 HU; P = 0.54) levels did not differ between FBP and IR groups, respectively. The IR group was associated to significant effective dose reductions, irrespective of the acquisition mode.
CONCLUSION: Application of IR in CTCA preserves image interpretability despite a significant reduction in radiation dose.Fil: Carrascosa, Patricia. Diagnóstico Maipú; ArgentinaFil: Rodriguez Granillo, Gaston Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Capuñay, Carlos. Diagnóstico Maipú; ArgentinaFil: Deviggiano, Alejandro. Diagnóstico Maipú; Argentin
Virtual Monochromatic Imaging in Patients with Intermediate to High Likelihood of Coronary Artery Disease: Impact of Coronary Calcification
No full textRationale and Objectives
We sought to explore the image quality and diagnostic performance of virtual monochromatic imaging derived from dual-energy computed tomography coronary angiography (DE-CTCA) in patients with intermediate to high likelihood of coronary artery disease (CAD) and the influence of calcification.
Materials and Methods
Consecutive symptomatic patients with suspected CAD referred for invasive coronary angiography who underwent DE-CTCA and a coronary artery calcium scoring before the invasive procedure comprised the study population.
Results
Sixty-seven patients were included. Image quality was significantly lower at 45 keV reconstructions (mean Likert score 45 keV 3.57 ± 0.6, 65 keV 4.07 ± 0.5, and 85 keV 4.09 ± 0.6; P < .0001). Patients with moderate calcification showed a trend toward a significant improvement in the diagnostic performance with 65 keV vs 45 keV reconstructions (45 keV, area under the curve 0.92 [95% confidence interval 0.89–0.95] vs 65 keV, area under the curve 0.96 [95% confidence interval 0.93–0.98], P = .06). The diagnostic performance of DE-CTCA was significantly lower in segments with higher coronary artery calcium scoring compared to segments with none or mild calcification, independent of the energy level applied.
Conclusions
In patients with intermediate to high likelihood of CAD, DE-CTCA had a good diagnostic performance, although significantly lower in segments with severe calcification.Fil: Carrascosa, Patricia. Diagnóstico Maipú; ArgentinaFil: Leipsic, Jonathon A.. St. Paul's Hospital; CanadáFil: Deviggiano, Alejandro. Diagnóstico Maipú; ArgentinaFil: Capunay, Carlos. Diagnóstico Maipú; ArgentinaFil: Vallejos, Javier. Diagnóstico Maipú; ArgentinaFil: Goldsmit, Alejandro. Sanatorio Güemes; ArgentinaFil: De Zan, Macarena. Diagnóstico Maipú; ArgentinaFil: Rodriguez Granillo, Gaston Alfredo. Diagnóstico Maipú; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Cardiológicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Cardiológicas; Argentin
Pericardial fat volume is related to atherosclerotic plaque burden rather than to lesion severity
No full textAims: We sought to explore the relationship between pericardial fat volume (PFV) and both coronary atherosclerosis (CA) extent and severity using coronary artery calcium score (CAC), computed tomography coronary angiography (CTCA), and invasive coronary angiography in patients at high to intermediate likelihood of coronary artery disease (CAD). Methods and results: Patients clinically referred to invasive angiography who underwent CTCA and CAC within 1 month before the procedure comprised the study population. PFV, CAC, atherosclerotic burden indexes [segment involvement score (SIS); segment stenosis score; three-vessel plaque; and any left main plaque], and the invasive angiography-derived CAD index were evaluated independently. A total of 75 patients were included in the study. PFV did not differ between patients with or without obstructive (stenosis .70%) CAD defined by invasive angiography (86.4±31.7 vs. 77.1±42.8 cm3, P = 0.34), although patients with obstructive CAD had significantly higher CAC scores [636.0 (IQR 229.5-1101.0) vs. 206.0 (IQR 0.0-675), P<0.0001] than patients without obstructive CAD. Patients with extensive CA (SIS . 5) had significantly larger PFV (89.9±33.9 vs. 58.7±33.2 cm3, P = 0.003) than patients with non-extensive CA. Significant correlations were found between PFV and CAC (r = 0.49, P<0.0001), and SIS (r = 0.46, P<0.0001), whereas very weak correlations were observed between PFV and the CAD index (r = 0.27, P = 0.02), and between PFV and the body mass index (r = 0.33, P = 0.004). Conclusion: The main finding of the present study was the identification of PFV as more closely related to atherosclerotic plaque burden rather than to lesion severity in patients referred to invasive coronary angiography.Fil: Rodriguez Granillo, Gaston Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Cardiológicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Cardiológicas; Argentina. Diagnóstico Maipú; ArgentinaFil: Carrascosa, Patricia. Diagnóstico Maipú; ArgentinaFil: Deviggiano, Alejandro. Diagnóstico Maipú; ArgentinaFil: Capunay, Carlos. Diagnóstico Maipú; ArgentinaFil: De Zan, Macarena C.. Diagnóstico Maipú; ArgentinaFil: Goldsmit, Alejandro. Sanatorio Güemes; ArgentinaFil: Campisi, Roxana. Diagnóstico Maipú; Argentin
Monochromatic image reconstruction by dual energy imaging allows half iodine load computed tomography coronary angiography
No full textPurpose: To compare image interpretability and diagnostic performance of dual-energy CT coronary angiography (DE-CTCA) performed with 50% iodine load reduction versus single energy acquisitions (SE-CTCA) with full iodine load. Materials and methods: The present prospective study involved patients with suspected coronary artery disease (CAD) clinically referred for CTCA. DE-CTCA with 50% iodine volume load was performed first, and after heart rate returned to baseline SE-CTCA was performed using full iodine volume load. The primary endpoint was to compare image interpretability between groups. DE-CTCA was performed by rapid switching between low and high tube potentials (80–140 kV) from a single source, allowing the generation of monochromatic image reconstructions ranging from 40 to 140 keV. Image quality assessment was performed using a 5-point Likert scale. Results: Thirty-six patients constituted the study population. The mean heart rate before the CT scan (DE-CTCA 57.3 ± 10.7 bpm vs. SE-CTCA 58.5 ± 11.2 bpm, p = 0.29) and the mean effective radiation dose (3.5 ± 1.9 mSv vs. 3.8 ± 0.9 mSv, p = 0.48) did not differ between groups. Likert image quality scores were similar between groups (DE-CTCA 4.42 ± 0.98 vs. SE-CTCA 4.43 ± 0.84, p = 0.67). Signal-to-noise and contrast-to-noise ratios were significantly lower with DE-CTCA, driven by lower signal density levels at 60 keV compared to SE-CTCA. The sensitivity and specificity for the detection of stenosis >50% was indistinguishable between groups (DE-CTCA 84.4% (69.9–93.0%), 87.1% (81.6–91.2%); SE-CTCA 84.4% (69.9–93.0%), 87.1% (81.6–91.2%). Conclusions: In this pilot, prospective study, dual energy CTCA imaging with half iodine load achieved comparable interpretability than full iodine load with single energy CTCA.Fil: Carrascosa, Patricia. Diagnostico Maipu; ArgentinaFil: Leipsic, Jonathon A.. St. Paul's Hospital; CanadáFil: Capunay, Carlos. Diagnostico Maipu; ArgentinaFil: Deviggiano, Alejandro. Diagnostico Maipu; ArgentinaFil: Vallejos, Javier. Diagnostico Maipu; ArgentinaFil: Goldsmit, Alejandro. Sanatorio Güemes; ArgentinaFil: Rodriguez Granillo, Gaston Alfredo. Diagnostico Maipu; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin
Spectral Signal Density of Carotid Plaque Using Dual-Energy Computed Tomography
No full textBACKGROUND AND PURPOSE: Plaque characterization using virtual monochromatic imaging derived from dual-energy computed tomography (CT) angiography requires the determination of normal signal density values of each plaque component. We sought to explore the signal density values of carotid plaque components using dual-energy compared to conventional single-energy CT angiography (CTA), and to establish the energy level with the largest differences between plaque components. METHODS: The present prospective study involved consecutive patients referred for carotid artery evaluation by CTA. Two scans (single-energy and dual-energy CTA) were performed in all patients, and a single radiologist analyzed the data. Single-source dual-energy CTA allowed the generation of virtual monochromatic images from 40 to 140 keV. RESULTS: A total of 35 internal carotid artery lesions were examined in 20 symptomatic patients. The mean age was 72.3 ± 6.7 years, and 9 (45%) patients were male. Internal carotid artery geometrical variables including lumen area (P =.96), vessel area (P =.97), and percent area stenosis (P =.99) did not differ between groups (single-energy CTA, and dual-energy CTA at 40, 70, 100, and 140 keV). Differences between signal densities of different tissues were largest at 40 keV (calcium/lumen, P <.0001; fat/noncalcified, P <.0001). CONCLUSIONS: In the present pilot investigation, virtual monochromatic imaging at low-energy levels derived from dual-energy CTA allowed the largest differences in attenuation levels between tissues, without affecting vessel or plaque geometry.Fil: Reynoso, Exequiel. Diagnostico Maipu; ArgentinaFil: Rodriguez Granillo, Gaston Alfredo. Diagnostico Maipu; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Capunay, Carlos. Diagnostico Maipu; ArgentinaFil: Deviggiano, Alejandro. Diagnostico Maipu; ArgentinaFil: Meli, Francisco. Diagnostico Maipu; ArgentinaFil: Carrascosa, Patricia. Diagnostico Maipu; Argentin
Improved Discrimination of Myocardial Perfusion Defects at Low Energy Levels Using Virtual Monochromatic Imaging
No full textObjectives: The aim of this study was to explore the diagnostic performance of dual-energy computed tomography perfusion (DE-CTP) at different energy levels. Methods: Patients with known or suspected coronary artery disease underwent stress and rest DE-CTP and single-photon emission computed tomography. Images were evaluated using monochromatic data, and perfusion defects were initially identified in a qualitative manner and subsequently confirmed using attenuation levels. Results: Thirty-six patients were included. Sensitivity, specificity, positive predictive value, and negative predictive value of DE-CTP for the identification of perfusion defects were 84.1%, 94.2%, 77.3%, and 96.2%, respectively. Perfusion defects showed significantly lower attenuation than normal segments, with the largest differences among low energy levels (sensitivity of 96% and specificity of 98% using a cutoff value ≤ 153 Hounsfield units at 40 keV), progressively declining at the higher levels (P < 0.001). Conclusions: Dual-energy CTP at the lowest energy levels allowed improved discrimination of perfusion defects compared with higher energy levels.Fil: Carrascosa, Patricia. Diagnóstico Maipú, Buenos Aires; ArgentinaFil: Deviggiano, Alejandro. Diagnóstico Maipú, Buenos Aires; ArgentinaFil: de Zan, Macarena. Diagnóstico Maipú, Buenos Aires; ArgentinaFil: Capunay, Carlos. Diagnóstico Maipú, Buenos Aires; ArgentinaFil: Campisi, Roxana. Diagnóstico Maipú, Buenos Aires; ArgentinaFil: Rodriguez Granillo, Gaston Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Cardiológicas. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Cardiológicas; Argentin
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