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    <title>Runza, G.</title>
    <link>http://repub.eur.nl/res/aut/15905/</link>
    <description>List of Publications</description>
    <language>en</language>
    <image>
      <url>http://repub.eur.nl/static-eur/img/logo.png</url>
      <title>RePub, Erasmus University Rotterdam</title>
      <link>http://repub.eur.nl</link>
    </image>
    <item>
      <title>Prognostic outcome of routine clinical noninvasive multidetector-row computed tomography coronary angiography in patients with suspected coronary artery disease: A 2-year follow-up study (Article)</title>
      <link>http://repub.eur.nl/res/pub/33422/</link>
      <pubDate>2011-06-01T00:00:00Z</pubDate>
      <description>Purpose: The aim of the study was to assess the prognostic value of multidetector-row CT coronary angiography (MDCT-CA) in patients with suspected coronary artery disease (CAD) in a routine clinical context. Materials and methods: A total of 125 patients (82 men, age 57.4±10.3 years) with suspected CAD underwent MDCT-CA. All patients were assessed for cardiovascular risk factors, symptoms and coronary calcium score. A 2-year follow-up study for the occurrence of major adverse cardiac events was performed. Results: According to the Morise pretest score, 76 patients (60.8%) were at intermediate risk. Patients with suspected CAD presented the following prognostic outcome (p&lt;0.0001): in 41 patients with normal coronary arteries at MDCT-CA, the event rate was 0%; five of 49 patients with nonobstructive CAD had major cardiac events; two of 35 patients with obstructive CAD suffered cardiac death and 19 underwent revascularisation. At multivariate analysis, the presence of obstructive CAD is the only significant independent prognostic variable (hazard ratio, 10.1393; 95% confidence interval 3.2189-31.9379; p&lt;0.0001). Conclusions: Routine clinical MDCT-CA provides an excellent prognostic value at 2-year follow-up in patients with normal coronary arteries. The cardiac event rate increases with CAD severity. </description>
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      <title>Atherosclerotic pattern of coronary myocardial bridging assessed with CT coronary angiography (Article)</title>
      <link>http://repub.eur.nl/res/pub/23216/</link>
      <pubDate>2011-02-25T00:00:00Z</pubDate>
      <description>The aim of our study was to evaluate the atherosclerotic pattern of patients with coronary myocardial bridging (MB) by means of CT Coronary Angiography (CT-CA). 254 consecutive patients (166 male, mean age 58.6 ± 10.3) who underwent 64-slice CT-CA according to current clinical indications were reviewed for the presence of MB and concomitant segmental atherosclerotic pattern. Coronary plaques were assessed in all patients enrolled. 73 patients (29%) presented single (90%) or multiple (10%) MB, frequently (93%) localized in the mid-distal left anterior descending artery. The MB segment was always free of atherosclerosis. Segments proximal to the MB presented: no atherosclerotic disease (n = 37), positive remodeling (n = 23), &lt;50% (n = 14), or &gt;50% stenoses (n = 7). Distal segments presented a different atherosclerosis pattern (P &lt; 0.0001): absence of disease (n = 73), no significant lesions (n = 8). No significant differences were found between segments proximal to MB and proximal coronary segments apart from left main trunk. Pattern of atherosclerotic lesions located in segments 6 and 7 significantly differs between patients with MB and patients without MB (P &lt; 0.05). CT-CA is a reliable method to non-invasively demonstrate MB and related atherosclerotic pattern. CT-CA provides new insight regarding atherosclerosis distribution in segments close to MB.</description>
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      <title>Lumen enhancement influences absolute noncalcific plaque density on multislice computed tomography coronary angiography: Ex-vivo validation and in-vivo demonstration (Article)</title>
      <link>http://repub.eur.nl/res/pub/28531/</link>
      <pubDate>2010-05-01T00:00:00Z</pubDate>
      <description>Aim: The purpose of this study was to define the in-vitro and in-vivo effects of intracoronary enhancement on the absolute density values of coronary plaques during multislice computed tomography. Methods: We studied seven ex-vivo left coronary artery specimens surrounded by olive oil and filled with isotonic saline and four solutions with decreasing dilutions of contrast material: control (isotonic saline), 1/200, 1/80, 1/50, and 1/20. The multislice computed tomography protocol was: slice/collimation 32 × 2 × 0.6 mm and rotation time 330 ms. The attenuation (Hounsfield units) value of atherosclerotic plaques was measured for each dilution in lumen, plaque (noncalcified coronary wall thickening), calcium, and surrounding oil. In-vivo assessment was performed in 12 patients (nine men; mean age 58.7 ± 9.9 years) who underwent two subsequent multislice computed tomography scans (arterial and delayed) after intravenous administration of a single bolus of contrast material. The attenuation values of lumen and plaques during arterial and delayed computed tomography were compared. The results were compared with one-way analysis of variance and correlated with Pearson's test. Results: Mean lumen (45 ± 38-669 ± 151 HU) and plaque (11 ± 35-101 ± 72 HU) attenuation differed significantly (P &lt; 0.001) among the different dilutions. The attenuation of lumen and plaque of coronary plaques showed moderate correlation (r = 0.54, P &lt; 0.001). The mean attenuation value in vivo for the arterial and delayed phase scans differed significantly (P &lt; 0.001) for lumen (325 ± 70 and 174 ± 46 HU, respectively) and plaque (138 ± 71 and 100 ± 52 HU, respectively). Conclusion: Coronary plaque attenuation values are significantly modified by differences in lumen contrast densities both ex vivo and in vivo. This should be taken into account when considering the distinction between lipid and fibrous plaques. </description>
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      <title>Prevalence of myocardial bridging and correlation with coronary atherosclerosis studied with 64-slice CT coronary angiography (Article)</title>
      <link>http://repub.eur.nl/res/pub/24232/</link>
      <pubDate>2009-10-01T00:00:00Z</pubDate>
      <description>Purpose: This study aimed to assess the prevalence and characteristics of myocardial bridging in patients who underwent multislice computed tomography coronary angiography (MSCT-CA) and to evaluate the correlation between bridged coronary segments and atherosclerosis. Materials and methods: A total of 277 patients (mean age 60±11 years) we consecutively examined with 64-slice MSCT-CA for suspected or known coronary atherosclerosis were retrospectively reviewed for myocardial bridging. Segments proximal and distal to the bridging were evaluated for atherosclerotic plaque, as were the remaining coronary segments. Results: Myocardial bridging was present in 82 patients (30%, mean age 59±12). Bridges were of variable length (&lt;1 cm 58%; 1-2 cm 32%; &gt;2 cm 10%) and depth (superficial 69%, intramyocardial 31%) and frequently localised in the mid-distal segment of the left anterior descending artery (95%). Myocardial bridging cannot be considered a significant risk factor for coronary atherosclerosis (odds ratio 0.49) compared with traditional cardiovascular risk factors. Coronary segments proximal to the bridge showed no atherosclerotic disease (33%), positive remodelling (27%), &lt;50% stenosis (20%) or &gt;50% stenosis (20%). We identified 12 noncalcified, 32 mixed and 17 calcified plaques. The distal segments were significantly less affected (p&lt;0.0001). Conclusions: MSCT-CA is a reliable, noninvasive method that is able to depict myocardial bridging and associated atherosclerotic plaque in the proximal segments. </description>
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      <title>ECG-gated multidetector computed tomography for the assessment of the postoperative ascending aorta (Article)</title>
      <link>http://repub.eur.nl/res/pub/24229/</link>
      <pubDate>2009-08-01T00:00:00Z</pubDate>
      <description>Purpose: This study was undertaken to define the role of electrocardiographically (ECG)-gated multidetector computed tomography (MDCT) in the assessment of the postoperative ascending aorta. Materials and methods: From November 2006 to June 2007, 21 patients, [11 men, ten women; age ± standard deviation (SD): 62.7±10.8 years] with a history of ascending aorta replacement underwent ECG-gated MDCT and were prospectively included in our study. Ascending aorta replacement had been performed with different surgical techniques: Bentall-De Bono (four patients, 19%), Tirone-David (five patients, 23%), and modified Tirone-David with creation of aortic neosinuses (12 patients, 57%). Two patients were excluded from MDCT evaluation because they failed to fulfil the inclusion criteria. Transthoracic echocardiography was used as the reference standard. All patients provided informed consent. Results: In all patients, ECG-gated MDCT provided a clear depiction of the aortic annulus, aortic root and ascending aorta, enabling accurate measurements in all cases. The aortic valve area (3.4±0.2 cm2), the diameter of the sinotubular junction (31.6±1.8 mm), the diameter of the neosinuses in the case of modified Tirone-David procedures (37.3±2.1 mm) and the distance between the cusps and the graft wall during systole (3.1±0.7 mm) fell within standard ranges and showed a good correlation (r=0.89) with the values obtained with transthoracic echocardiography. Conclusions: MDCT is currently considered a compulsory diagnostic step in patients with suspected or known aortic pathology. MDCT is a reliable technique for anatomical and functional assessment of the postoperative aortic root and provides cardiac surgeons with new and detailed information, enabling them to formulate a prognostic opinion regarding the outcome of the surgical procedure. </description>
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      <title>Assessment of left main coronary artery atherosclerotic burden using 64-slice CT coronary angiography: Correlation between dimensions and presence of plaques (Article)</title>
      <link>http://repub.eur.nl/res/pub/24227/</link>
      <pubDate>2009-04-01T00:00:00Z</pubDate>
      <description>Purpose: The aim of this study was to correlate left main (LM) coronary artery dimensions with the presence of atherosclerosis by multidetector-row computed tomography (MDCT) coronary angiography (CA) and to assess coronary atherosclerotic plaques with a semiquantitative method. Materials and methods: Sixty-two consecutive patients (41 men, mean age 60±11) with suspected coronary artery disease underwent 64-MDCT coronary angiography. LM dimensions (length, ostial and bifurcation diameters), quantitative [location, Hounsfield unit (HU) attenuation] and qualitative (composition, shape) analysis of plaques within the LM were performed. All patients underwent conventional CA. Results: Thirty patients (mean age 55±10) without plaques in the LM presented the following average dimensions: length 10.6±6.1 mm, ostial diameter 5.5±0.7 mm, bifurcation diameter 4.9±0.9 mm. LM plaques (n=36) were detected in 32 patients (mean age 64±10) with the following LM average dimensions: length 11.3±4.0 mm, ostial diameter 6.0±1.2 mm and bifurcation diameter 6.0±1.2 mm. Plaques were calcified (40%, mean attenuation 742±191 HU), mixed (43%, mean attenuation 387±94 HU) or noncalcified (17%, mean attenuation 56±14 HU) and were frequently eccentric (77%). Age was significantly different in the two groups (p&lt;0.05). LM diameters of patients with plaques were improved (p&lt;0.05). A moderate correlation was found between the LM bifurcation diameter and the corresponding plaque area (r=0.56). Significant conventional CA lesions of the LM were present in just three patients (5%). Conclusions: Increased LM diameters are associated with the presence of atherosclerosis. MDCT CA indicates relevant features of LM atherosclerotic burden, as rupture and subsequent thrombosis of vulnerable plaques may develop from lesions characterised as nonsignificant at conventional CA. </description>
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      <title>Influence of heart rate in the selection of the optimal reconstruction window in routine clinical multislice coronary angiography (Article)</title>
      <link>http://repub.eur.nl/res/pub/29217/</link>
      <pubDate>2008-08-01T00:00:00Z</pubDate>
      <description>Purpose. The aim of our study was to assess the influence of heart rate on the selection of the optimal reconstruction window with 40-slice multidetector-row computed tomography (40-MDCT) coronary angiography. Materials and methods. We studied 170 patients (114 men, age 60±11.3 years) with suspected or known coronary artery disease with 40-MDCT coronary angiography. Patients [mean heart rate (HR) 62.9±9.3 bpm, range 42-94 bpm] were clustered in two groups (group A: HR ≤65 bpm; group B: HR &gt;65 bpm). Multiphase reconstruction data sets were obtained with a retrospective electrocardiogram (ECG)-gated 40-MDCT coronary angiography scan from 0% to 95% every 5% of the R-R interval. Two radiologists in consensus evaluated the best data sets for diagnostic purposes. Results. In group A, the optimal reconstruction windows were at 70% (55/110, 71/110 and 69/110 for the right coronary artery, left anterior descending and the left circumflex, respectively) and 75% (26/110, 28/110 and 28/110, respectively) of the R-R interval. In group B, a wide range of reconstruction windows were employed, both in the end-systolic phase at 40% (32/60, 18/60 and 17/60, for the right coronary artery, left anterior descending and circumflex, respectively) and diastolic phases at 70% (12/60, 22/60 and 19/60, respectively). Six scans were excluded due to severe respiratory artefacts. Conclusions. Optimal position of the image reconstruction window relative to the cardiac cycle is significantly influenced by the heart rate during scanning. Diastolic reconstruction phases often allowed an optimal assessment in group A. Reconstruction phases from 30% to 45% are advisable for higher heart rates. </description>
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      <title>Prevalence and characteristics of coronary artery disease in a population with suspected ischaemic heart disease using CT coronary angiography: Correlations with cardiovascular risk factors and clinical presentation (Article)</title>
      <link>http://repub.eur.nl/res/pub/29136/</link>
      <pubDate>2008-04-01T00:00:00Z</pubDate>
      <description>Purpose. This study was undertaken to describe the correlation between the distribution of coronary artery disease (CAD) in a symptomatic population with suspected ischaemic heart disease, cardiovascular risk factors (RF) and clinical presentation. Materials and methods. We studied 163 patients (mean age 65.5 years; 101 men and 62 women) referred for multidetector computed tomography coronary angiography (MDCT-CA) to rule out CAD. The patients had no prior history of revascularisation or myocardial infarction. We analysed how the characteristics of CAD (severity and type of plaque) can change with the increase in RF and how they are related to different clinical presentations. Results. Patients were divided into three groups according to the number of RF: zero or one, two or three, and four or more. The percentage of coronary arteries with no plaque, nonsignificant disease and significant disease was 55%, 41% and 4%, respectively, in patients with zero or one RF; 27%, 51% and 22%, respectively, in patients with two or three RF; and 19%, 38% and 44%, respectively, in patients with four or more RF. Plaque in patients with nonsignificant disease was mixed in 65%, soft in 18% and calcified in 17%. The percentage of coronaries with no plaque in the three RF groups was 50%, 20% and 0% in patients with typical chest pain and 46%, 24% and 12% in those with atypical pain. The percentage of significant disease in patients with typical pain was 0%, 47% and 86% and in those with atypical pain 4%, 20% and 29%. Conclusions. MDCT plays an important role in the identification of CAD in patients with suspected ischaemic heart disease. Severity and type of disease is highly correlated with RF number and assumes different characteristics according to clinical presentation. </description>
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      <title>Coronary variants and anomalies: Methodology of visualisation with 64-slice CT and prevalence in 202 consecutive patients (Article)</title>
      <link>http://repub.eur.nl/res/pub/35087/</link>
      <pubDate>2007-12-01T00:00:00Z</pubDate>
      <description>Purpose. This paper aims to provide the tools for a complete anatomical evaluation of the coronary tree using 64-slice computed tomography (CT) and evaluate the prevalence of anatomical variants and anomalies in a population of 202 consecutive patients. Materials and methods. Two hundred and two patients with suspected coronary artery disease underwent 64-slice CT with a standard protocol. Two observers working in consensus evaluated and collected the data regarding anatomical variants and anomalies of the coronary vessels. Results. In the 202 consecutive patients, the prevalence of anatomical variants was: left dominant circulation (7%), absent left main (5%), presence of intermediate branch (17%), aortic origin of conus branch (13%) and circumflex origin of sinus node branch (15%). Coronary anomalies (origin and course, intrinsic and termination) showed an overall prevalence of 25%. Conclusions. CT is the ideal method for the three-dimensional evaluation of the coronary tree. Anatomical variants and anomalies of the coronary arteries are quite common and should be known and recognised promptly by the operators. </description>
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      <title>Comprehensive cardiovascular ECG-gated MDCT as a standard diagnostic tool in patients with acute chest pain (Article)</title>
      <link>http://repub.eur.nl/res/pub/36179/</link>
      <pubDate>2007-10-01T00:00:00Z</pubDate>
      <description>Acute myocardial infarction, pulmonary embolism, and aortic dissection are diseases associated with acute chest pain and may lead to severe morbidity and mortality. These diseases may not be trivial to diagnose in the settings of emergency room. ECG-gated multi-detector computed tomography (MDCT), already established for the assessment of pulmonary embolism and aortic dissection, provides reliable information regarding the triage of patients with acute coronary syndrome in the emergency room. MDCT recently appeared to be logistically feasible and a promising comprehensive method for the evaluation of cardiac and non-cardiac chest pain in emergency department patients. The possibility to scan the entire thorax visualizing the thoracic aorta, the pulmonary arteries, and the coronary arteries could provide a new approach to the triage of acute chest pain. The inherent advantage of MDCT with cardiac state-of-the-art capabilities is the rapid investigation of the main sources of acute chest pain with a high negative predictive value. Recent studies also reports an advantage in terms of costs. With current evidence, the selection of patients with acute chest pain candidates to MDCT should remain restricted to avoid unjustified risk of ionizing radiation. </description>
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      <title>Can ECG-gated MDCT be considered an obligatory step to plan and manage a new chest-pain unit? (Article)</title>
      <link>http://repub.eur.nl/res/pub/36182/</link>
      <pubDate>2007-10-01T00:00:00Z</pubDate>
      <description>The recent improvements in multi-detector computed tomography technology and its application in cardiac field allow to consider this non-invasive imaging technique as a promising comprehensive method for detecting significant coronary stenoses in a chest-pain unit. The possibility to use the ECG-synchronisation acquisition protocol, normally limited to the cardiac volume, for the entire thoracic vascular system should have the remarkable potential to reduce invasive and non-invasive procedures actually used to investigate acute chest pain and the number of unnecessary hospital admissions without reducing appropriate admissions in patients with chest pain. </description>
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      <title>Diagnostic accuracy of 64-slice computed tomography coronary angiography in patients with low-to-intermediate risk (Article)</title>
      <link>http://repub.eur.nl/res/pub/35167/</link>
      <pubDate>2007-10-01T00:00:00Z</pubDate>
      <description>Purpose. Our aim was to evaluate the diagnostic accuracy of 64-slice computed tomography coronary angiography (MSCT-CA) for detecting significant stenosis (≥50% lumen reduction) in a population of patients at low to intermediate risk. Materials and methods. We studied 72 patients (38 men, 34 women, mean age 53.9±8.0 years) with atypical or typical chest pain and stratified in the low-to intermediate risk category. MSCT-CA (Sensation 64 Cardiac, Siemens, Germany) was performed after IV administration of 100 ml of iodinated contrast material (Iomeprol 400 mgI/ml, Bracco, Italy). Two observers, blinded to the results of conventional coronary angiography (CAG), assessed the MSCT-CA scans in consensus. Diagnostic accuracy for detecting significant stenosis was calculated. Results. CAG demonstrated the absence of significant disease in 70.1% of patients (51/72). No patient was excluded from MSCT-CA. There were 37 significant lesions on 1,098 available coronary segments. Sensitivity, specificity and positive and negative predictive value of MSCT-CA for detecting significant coronary artery on a per-segment basis were 100%, 98.6%, 71.2% and 100%, respectively. All patients with at least one significant lesion were correctly identified by MSCT-CA. MSCT-CA scored 15 false positives on a per-segment base, which affected only marginally the per-p.atient performance (only one false positive). Conclusions. We concluded that 64-slice CT-CA is a diagnostic modality with high sensitivity and negative predictive value in patients at low to intermediate risk. </description>
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      <title>Spectrum of collateral findings in multislice CT coronary angiography (Article)</title>
      <link>http://repub.eur.nl/res/pub/35192/</link>
      <pubDate>2007-10-01T00:00:00Z</pubDate>
      <description>Purpose. The aim of the study was to investigate the prevalence of the noncardiac collateral findings during multislice computed tomography coronary angiography (MSCT-CA). Materials and methods. Six hundred and seventy patients undergoing MSCT-CA with 16-slice and 64-slice CT scanners for suspected atherosclerotic disease of the coronary arteries were retrospectively reviewed. All data sets obtained with a large field of view (FOV) were analysed by two radiologists using standard mediastinal and lung window settings. Collateral findings were divided according to clinical importance into nonsignificant, remarkable and compulsory to be investigated. Results. Eighty-five percent of patients revealed coronary artery disease (CAD). Only 138/670 (20.6%) were without any additional finding. An additional 1,234 findings were recorded: nonsignificant 332 (26.9%), mild 821 (66.53%), compulsory for study 81 (6.56%). A total of 81 patients (12.08%) had significant noncardiac pathology requiring clinical or radiological follow-up. Among these, newly discovered pathologies were revealed in two patients (2.46%). Conclusions. A significant number of noncardiac findings might have been missed in MSCT-CA scans; the appropriate approach should be as a team trained in cardiology and radiology. </description>
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      <title>Imaging techniques for the vulnerable coronary plaque (Article)</title>
      <link>http://repub.eur.nl/res/pub/35272/</link>
      <pubDate>2007-08-01T00:00:00Z</pubDate>
      <description>The goal of this article is to illustrate the main invasive and noninvasive diagnostic modalities to image the vulnerable coronary plaque, which is responsible for acute coronary syndrome. The main epidemiologic and histological issues are briefly discussed in order to provide an adequate background. Comprehensive coronary atherosclerosis imaging should involve visualization of the entire coronary artery tree and plaque characterization, including three-dimensional morphology, relationship with the lumen, composition, vascular remodelling and presence of inflammation. No single technique provides such a comprehensive description, and no available modality extensively identifies the vulnerable plaque. In particular, we describe multislice computed tomography, which at present seems to be the most promising noninvasive tool for an exhaustive image-based quantification of coronary atherosclerosis. </description>
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      <title>Adjunctive value of CT coronary angiography in the diagnostic work-up of patients with typical angina pectoris (Article)</title>
      <link>http://repub.eur.nl/res/pub/35764/</link>
      <pubDate>2007-08-01T00:00:00Z</pubDate>
      <description>Aims: To determine the adjunctive value of CT coronary angiography (CTCA) in the diagnostic work-up of patients with typical angina pectoris. Methods and results: CTCA was performed in 62 consecutive patients (45 male, mean age 58.8 ± 7.7 years) with typical angina undergoing diagnostic work-up including exercise-ECG and conventional coronary angiography. Only patients with sinus heart rhythm and ability to breath hold for 20 s were included. Patients with initial heart rates ≥70 beats/min received β-blockers. We determined the post-test likelihood ratios, to detect or exclude patients with significant (≥50% lumen diameter reduction) stenoses, of exercise-ECG and CTCA separately, and of CT performed after exercise-ECG testing. The prevalence of patients with significant coronary artery disease (CAD) was 74%. Positive and negative likelihood ratios for exercise-ECG were 2.3 [95% confidence interval (CI): 1.0-5.3] and 0.3 (95% CI: 0.2-0.7) and for CTCA 7.5 (95% CI: 2.1-27.1) and 0.0 (95% CI: 0.0-8), respectively. CTCA increased the post-test probability of significant CAD after a negative exercise-ECG from 58 to 91%, and after a positive exercise-ECG from 89 to 99%, while CT correctly identified patients without CAD (probability 0%). Conclusion: Non-invasive CTCA is a potentially useful tool, in the diagnostic work-up of patients with typical angina pectoris, both to detect and to exclude significant CAD. </description>
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      <title>Influence of convolution filtering on coronary plaque attenuation values: Observations in an ex vivo model of multislice computed tomography coronary angiography (Article)</title>
      <link>http://repub.eur.nl/res/pub/36441/</link>
      <pubDate>2007-07-01T00:00:00Z</pubDate>
      <description>Attenuation variability (measured in Hounsfield Units, HU) of human coronary plaques using multislice computed tomography (MSCT) was evaluated in an ex vivo model with increasing convolution kernels. MSCT was performed in seven ex vivo left coronary arteries sunk into oil followingthe instillation of saline (1/∞) and a 1/50 solution of contrast material (400 mgI/ml iomeprol). Scan parameters were: slices/ collimation, 16/0.75 mm; rotation time, 375 ms. Four convolution kernels were used: b30f-smooth, b36f-medium smooth, b46f-medium and b60f-sharp. An experienced radiologist scored for the presence of plaques and measured the attenuation in lumen, calcified and noncalcified plaques and the surrounding oil. The results were compared by the ANOVA test and correlated with Pearson's test. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were calculated. The mean attenuation values were significantly different between the four filters (p&lt;0.0001) in each structure with both solutions. After clustering for the filter, all of the noncalcified plaque values (20.8±39.1, 14.2±35.8, 14.0±32.0, 3.2±32.4 HU with saline; 74.7±66.6, 68.2±63.3, 66.3±66.5, 48.5±60.0 HU in contrast solution) were significantly different, with the exception of the pair b36f-b46f, for which a moderate-high correlation was generally found. Improved SNRs and CNRs were achieved by b30f and b46f. The use of different convolution filters significantly modifief the attenuation values, while sharper filtering increased the calcified plaque attenuation and reduced the noncalcified plaque attenuation. </description>
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      <title>Diagnostic accuracy of 64-slice CT in the assessment of coronary stents (Article)</title>
      <link>http://repub.eur.nl/res/pub/35373/</link>
      <pubDate>2007-06-01T00:00:00Z</pubDate>
      <description>Purpose. The purpose of this study was to assess the diagnostic accuracy of 64-slice computed tomography (64-CT) coronary angiography in the detection of coronary in-stent restenosis. Materials and methods. Ninety-five patients (72 men and 23 women, mean age 58±8 years) with previous percutaneous coronary intervention with stenting and suspected restenosis underwent 64-CT (Sensation 64, Siemens). The mean time between stent deployment and 64-CT was 6.1±4.2 months. The scan parameters were: slices 32×2, individual detector width 0.6 mm, rotation time 0.33 s, feed 3.84 mm/rotation, 120 kV, 900 mAs. After the intravenous administration of iodinated contrast material (Iomeprol 400 mgI/ml, Iomeron, Bracco) and a bolus chaser (40 ml of saline), the scan was completed in &lt;12 s. All coronary segments with a stent were assessed on 64-CT by two observers in consensus and judged as: patent, with intimal hyperplasia (lumen reduction of &lt;50%), with in-stent restenosis (≥50%), or with in-stent occlusion (100%). The consensus reading was compared with conventional coronary angiography. Results. Four patients were excluded because of insufficient image quality. In the remaining 91, we assessed 102 stents (31 RCA; 10 LM; 54 LAD; 7 CX). In 14 (13.7%) stents, in-stent restenosis (n=8) or in-stent occlusion (n=6) was found. Intimal hyperplasia was detected in 11 (10.8%) stents. The sensitivity and negative predictive value of 64-CT for in-stent occlusion were 100% and 100%, respectively, whereas for all stenoses, &gt;50% they were 92.9% and 98.7%, respectively. Conclusions. We found that 64-CT has a high diagnostic accuracy for the detection of in-stent restenosis in a selected patient population. </description>
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      <title>Three-dimensional quantitative assessment of lung parenchyma in cystic fibrosis: Preliminary results (Article)</title>
      <link>http://repub.eur.nl/res/pub/35579/</link>
      <pubDate>2007-02-01T00:00:00Z</pubDate>
      <description>Purpose. The aim of this study was to assess the feasibility of three-dimensional (3D) reconstructions and quantitative analysis of the volume of each component of the lung with cystic fibrosis (CF). Materials and methods. Twenty-two patients with CF (mean age 17±8 yeas) were included in the study. The patients underwent an unenhanced single-slice spiral computed tomography (CT) chest scan with the following parameters: collimation 3 mm, table feed 6 mm×rot-1, reconstruction interval 1 mm, soft tissue reconstruction kernel. Four image data sets were obtained: native axial slices, cine-mode display, virtual bronchographic volumerendered images with algorithm for tissue transition display and virtual endoluminal views. The lungs were segmented manually from the hilum to the visceral pleura on the axial images, and the entire lung volume was calculated. A histogram was generated representing the fractional volume of tissues, the density of which was within a preset range. A curve was then obtained from the histogram. Results. Native axial images and cine-mode display allowed complete evaluation of lung volumes. Virtual bronchography allowed a better assessment of the distribution of bronchiectasis. Virtual bronchoscopy was limited by the fact that it visualised only the surface, without differentiating mucus from the bronchial wall. Manual segmentation and generation of density-volume curves required 41±7 min for each lung. Three curve patterns were identified depending on disease severity. Conclusions. Volume-density analysis of lungs with CF is feasible. Its main advantage is that image analysis is not analogical, as the assessment is not performed using scoring systems or similar ordinal scales. This technique cannot differentiate acute from chronic findings, and the predictive value of the curve should be assessed. </description>
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      <title>High-resolution spiral computed tomography coronary angiography in patients referred for diagnostic conventional coronary angiography. (Article)</title>
      <link>http://repub.eur.nl/res/pub/13936/</link>
      <pubDate>2005-10-11T00:00:00Z</pubDate>
      <description>BACKGROUND: The diagnostic performance of the latest 64-slice CT scanner, with increased temporal (165 ms) and spatial (0.4 mm3) resolution, to detect significant stenoses in the clinically relevant coronary tree is unknown. METHODS AND RESULTS: We studied 52 patients (34 men; mean age, 59.6+/-12.1 years) with atypical chest pain, stable or unstable angina pectoris, or non-ST-segment elevation myocardial infarction scheduled for diagnostic conventional coronary angiography. All patients had stable sinus rhythm. Patients with initial heart rates &gt; or =70 bpm received beta-blockers. Mean scan time was 13.3+/-0.9 seconds. The CT scans were analyzed by 2 observers unaware of the results of invasive coronary angiography, which was used as the standard of reference. All available coronary segments, regardless of size, were included in the evaluation. Lesions with &gt; or =50 luminal narrowing were considered significant stenoses. Invasive coronary angiography demonstrated the absence of significant disease in 25% (13 of 52), single-vessel disease in 31% (16 of 52), and multivessel disease in 45% (23 of 52) of patients. One unsuccessful CT scan was classified as inconclusive. Ninety-four significant stenoses were present in the remaining 51 patients. Sensitivity, specificity, and positive and negative predictive values of CT for detecting significant stenoses on a segment-by-segment analysis were 99% (93 of 94; 95% CI, 94 to 99), 95% (601 of 631; 95% CI, 93 to 96), 76% (93 of 123; 95% CI, 67 to 89), and 99% (601 of 602; 95% CI, 99 to 100), respectively. CONCLUSIONS: Noninvasive 64-slice CT coronary angiography accurately detects coronary stenoses in patients in sinus rhythm and presenting with atypical chest pain, stable or unstable angina, or non-ST-segment elevation myocardial infarction.</description>
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