Coronary Artery Disease: van Ooijen PM

Oudkerk M, Stillman AE, Halliburton SS, Kalender WA, Möhlenkamp S, McCollough CH, Vliegenthart R, Shaw LJ, Stanford W, Taylor AJ, van Ooijen PM, Wexler L, Raggi P, Anonymous00008, Anonymous00009. · Department of Radiology, Groningen University Hospital, Hanzeplein 1, 9700 RB, Groningen, The Netherlands. · Eur Radiol. · Pubmed #18651153 No free full text.

Abstract: Current guidelines and literature on screening for coronary artery calcium for cardiac risk assessment are reviewed for both general and special populations. It is shown that for both general and special populations a zero score excludes most clinically relevant coronary artery disease. The importance of standardization of coronary artery calcium measurements by multidetector CT is discussed.

Oudkerk M, Stillman AE, Halliburton SS, Kalender WA, Möhlenkamp S, McCollough CH, Vliegenthart R, Shaw LJ, Stanford W, Taylor AJ, van Ooijen PM, Wexler L, Raggi P. · Department of Radiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. · Int J Cardiovasc Imaging. · Pubmed #18504647 links to  free full text

Abstract: Current guidelines and literature on screening for coronary artery calcium for cardiac risk assessment are reviewed for both general and special populations. It is shown that for both general and special populations a zero score excludes most clinically relevant coronary artery disease. The importance of standardization of coronary artery calcium measurements by multi-detector CT is discussed.

van Geuns RJ, Wielopolski PA, de Bruin HG, Rensing BJ, van Ooijen PM, Hulshoff M, Oudkerk M, de Feyter PJ. · Department of Cardiology, Thoraxcenter, Dr Daniel den Hoedkliniek, University Hospital Rotterdam, The Netherlands. · Prog Cardiovasc Dis. · Pubmed #10555116 No free full text.

Abstract: Recently a new noninvasive imaging technique, magnetic resonance imaging (MRI) has been developed that has the potential to assess the coronary arteries. MRI of the coronary arteries is a challenging task because of the motion of the vessels during cardiac contraction and the motion of the heart with respiration. Several two-dimensional and three-dimensional acquisition techniques have been developed to overcome these problems. In this article we will describe different conventional MR techniques such as spin-echo and gradient-echo imaging. Also, we will describe new developments in MRI as ultrafast breathhold techniques using echo planar imaging or targeted volume scanning. Other new developments are respiratory gating techniques with or without respiratory motion correction. Finally, we will review the results of these techniques in the detection of coronary artery bypass graft patency, coronary artery stenosis, and the evaluation of coronary artery anomalies.

van Geuns RJ, Wielopolski PA, Rensing BJ, van Ooijen PM, Oudkerk M, de Feyter PJ. · Department of Cardiology, University Hospital Rotterdam, The Netherlands. · Coron Artery Dis. · Pubmed #10376205 No free full text.

Abstract: Magnetic resonance imaging of coronary arteries will visualize, besides the arteries, the myocardium, blood in the cavities and cardiac veins. This will hamper the application of projectional visualization techniques such as those used in conventional coronary angiography. Volume rendering, a different visualization technique, can be used to create a three-dimensional impression of a magnetic resonance data set on a two-dimensional surface. In this article, we will review the volume-rendering technique and anatomy of the coronary arteries and veins in the obtained images. Also we will discuss the relation between arteries and veins and the possible sites of confusion.

van Ooijen PM, Nieman K, de Feyter PJ, Oudkerk M. · Department of Radiology, University Hospital Groningen, Groningen, The Netherlands. · Am J Cardiol. · Pubmed #12398971 No free full text.

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Dorgelo J, Willems TP, Geluk CA, van Ooijen PM, Zijlstra F, Oudkerk M. · Department of Radiology, University Hospital Groningen, Groningen, The Netherlands. · Eur Radiol. · Pubmed #15449001 No free full text.

Abstract: Patients with non-ST elevation acute coronary syndrome (ACS) and evidence of myocardial ischaemia are scheduled for coronary angiography (CAG). In most patients CAG remains a single diagnostic procedure only. A prospective study was performed to evaluate whether 16-slice multidetector CT (MDCT) could predict treatment of the patients and to determine how many CAGs could have been prevented by MDCT scanning prior to CAG. Twenty-two patients with ACS were scanned prior to CAG. Based on MDCT data, a fictive treatment was proposed and compared to CAG-based treatment. Excellent accuracy was observed to detect significant stenoses using MDCT (sensitivity 94%, specificity 96%). In 45%, no PCI was performed during CAG, because of the absence of significant coronary artery disease (27%) or severe coronary artery disease, demanding CABG (18%). MDCT predicted correct treatment in 86%. By using MDCT data, 32% of the CAGs could have been prevented.

van Ooijen PM, Vliegenthart R, Witteman JC, Oudkerk M. · Department of Radiology, Groningen University Hospital, P.O. Box 30001, 9700 RB Groningen, The Netherlands. · Eur Radiol. · Pubmed #15372193 No free full text.

Abstract: Current multi-detector CT and electron beam tomography (EBT) technology enables the evaluation of coronary calcification. Multiple software packages are available to quantify calcification using several scoring algorithms implementing user-definable scoring parameters. We investigated the effect of scoring parameters on the calcium score outcome. Three parameters (four-connected or eight-connected, lesion size threshold and interpolation) are evaluated. Their theoretical influence on the scoring outcome is shown using simplified examples. To evaluate the effect in real data, we performed calcium scoring on randomly chosen EBT scans from 50 participants in an epidemiological study. Both the Agatston and volume scores were calculated. Changing from eight-connected to four-connected connectivity decreased both Agatston and volume scores (mean variability Agatston 3.15% and volume score -3.52%). Decreasing the threshold from 4 to 2 pixels increased the calcium scores because smaller lesions were also selected as calcified plaques (mean variability Agatston 16.23% and volume score 18.66%). Finally, the use of interpolation had a large negative effect on the volume score (mean variability -29.67%) and almost no effect on the Agatston score. Parameter settings in software for quantification for coronary calcification affect the calcium score outcome. Therefore, parameter settings for calcium scoring should be standardized.

van Ooijen PM, Ho KY, Dorgelo J, Oudkerk M. · Department of Radiology, Groningen University Hospital, Hanzeplein 1, 9700 RB, Groningen, The Netherlands. · Radiographics. · Pubmed #12907810 links to  free full text

Abstract: Noninvasive imaging of the coronary arteries has attracted growing interest in the past few years. One of the possible acquisition techniques is multidetector computed tomography (CT) that produces large three-dimensional (3D) data sets that require visualization techniques for data evaluation. The objective of this article is to increase knowledge of possible 3D visualization techniques together with their advantages and disadvantages for the routine evaluation of cardiac data sets. Common imaging techniques available to the radiologist at standard workstations are multiplanar reformation (MPR), oblique MPR, curved MPR, maximum-intensity projection (MIP), shaded-surface display, and direct volume rendering. Each of these techniques has its advantages and disadvantages for the visualization of the coronary artery tree. Several additions to the basic techniques have been developed to overcome some of their shortcomings. Different clinical examinations, such as stent evaluation, stenosis evaluation, and bypass evaluation, require different visualization techniques. The choice of preferred technique for each clinical study depends on the advantages and disadvantages of the various techniques as described in the literature. Because of the large number of possible settings and projection angles, it is important for users to interactively manipulate the images and review the whole vessel volume rather than just looking at static reformatted images. Errors such as findings of false stenoses can be avoided by means of accurate and appropriate use of software features. This requires training of users both with regard to the capabilities of the software and the background of the different techniques and their possible pitfalls. The authors believe that volume rendering of the whole heart is useful for anatomic evaluation of the coronary arteries. For more detailed observation of specific lesions, slab imaging with volume rendering or MIP is required.

van Ooijen PM, van Geuns RJ, Rensing BJ, Bongaerts AH, de Feyter PJ, Oudkerk M. · Department of Radiology, University Hospital Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands. · AJR Am J Roentgenol. · Pubmed #12490509 links to  free full text

Abstract: OBJECTIVE: Three-dimensional data for noninvasive imaging of the coronary arteries are acquired from electron beam CT, multidetector CT, or MR imaging. Most commonly, surface rendering is used for three-dimensional processing, but recent advances in hardware and software technology have made it possible to use volume rendering. Our objective was to compare volume rendering with surface rendering for the visualization of the coronary artery tree. CONCLUSION: Our experience in the comparison of both techniques shows that because of intrinsic problems associated with surface rendering, volume rendering produces better image quality.

Rensing BJ, Bongaerts AH, van Geuns RJ, van Ooijen PM, Oudkerk M, de Feyter PJ. · Department of Cardiology, Thoraxcenter BD 416, Erasmus University Rotterdam, Dr Molewaterplein 40, 3015 GD Rotterdam, Netherlands. · Heart. · Pubmed #10490574 links to  free full text

Abstract: Intravenous coronary angiography with electron beam computed tomography (EBCT) allows for the non-invasive visualisation of coronary arteries. With dedicated computer hardware and software, three dimensional renderings of the coronary arteries can be constructed, starting from the individual transaxial tomograms. This article describes image acquisition, postprocessing techniques, and the results of clinical studies. EBCT coronary angiography is a promising coronary artery imaging technique. Currently it is a reasonably robust technique for the visualisation and assessment of the left main and left anterior descending coronary artery. The right and circumflex coronary arteries can be visualised less consistently. Improvements in image acquisition and postprocessing techniques are expected to improve visualisation and diagnostic accuracy of the technique.

van Geuns RJ, de Bruin HG, Rensing BJ, Wielopolski PA, Hulshoff MD, van Ooijen PM, Oudkerk M, de Feyter PJ. · Department of Cardiology, Thoraxcenter, University Hospital Rotterdam, Dr Molewaterplein 40, 3015 GD Rotterdam, Netherlands. · Heart. · Pubmed #10490571 links to  free full text

Abstract: BACKGROUND: Magnetic resonance coronary angiography is challenging because of the motion of the vessels during cardiac contraction and respiration. Additional challenges are the small calibre of the arteries and their complex three dimensional course. Respiratory gating, turboflash acquisition, and volume rendering techniques may meet the necessary requirements for appropriate visualisation. OBJECTIVE: To determine the diagnostic accuracy of respiratory gated magnetic resonance imaging (MRI) for the detection of significant coronary artery stenoses evaluated with three dimensional postprocessing software. METHODS: 32 patients referred for elective coronary angiography were studied with a retrospective respiratory gated three dimensional gradient echo MRI technique. Resolution was 1.9 x 1.25 x 2 mm. After manual segmentation three dimensional evaluation was performed with a volume rendering technique. RESULTS: Overall 74% (range 50% to 90%) of the proximal and mid coronary artery segments were visualised with an image quality suitable for further analysis. Sensitivity and specificity for the detection of significant stenoses were 50% and 91%, respectively. CONCLUSIONS: Volume rendering of respiratory gated MRI techniques allows adequate visualisation of the coronary arteries in patients with a regular breathing pattern. Significant lesions in the major coronary artery branches can be identified with a moderate sensitivity and a high specificity.