Mark W. Heijenbrok

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OBJECTIVES This study sought to demonstrate the feasibility of a dedicated algorithm for automated quantification of stenosis severity on multislice computed tomography in comparison with quantitative coronary angiography (QCA). BACKGROUND Limited information is available on quantification of coronary stenosis, and previous attempts using semiautomated(More)
PURPOSE In radiotherapy for left-sided breast cancer, Active Breathing Control enables a decrease of cardiac and Left Anterior Descending (LAD) coronary artery dose. We compared 3D-Conformal (3D-CRT) to Intensity Modulated Radiotherapy (IMRT) treatment plans based on free-breathing (FB) and breath-hold (BH). We investigated whether IMRT enables an(More)
In this study the vibratory perception threshold (VPT) and the thermal discrimination threshold (TDT) were measured in 33 patients with clinically definite multiple sclerosis (MS). VPT values were abnormal in a majority of MS patients (68%). There was no relation between VPT and the severity of the disease. TDT values were elevated less frequently (30%);(More)
In this study blood pressure (BP) and heart rate (HR) responses to standing and HR responses to deep breathing were assessed in 34 patients with clinically definite multiple sclerosis (MS) and 63 healthy subjects. Normal ranges, which were clearly age related for both HR responses, were obtained. The BP response to standing was abnormal in 13% of the MS(More)
PURPOSE To examine MRI and CT for glandular breast tissue (GBT) volume delineation and to assess interobserver variability. METHODS AND MATERIALS Fifteen breast cancer patients underwent a planning CT and MRI, consecutively, in the treatment position. Four observers (two radiation oncologists and two radiologists) delineated the GBT according to the CT(More)
BACKGROUND Although atrial fibrillation (AF) has been linked to underlying coronary artery disease (CAD), data supporting this association have been based on ECG and clinical history for the definition of CAD rather than direct visualization of atherosclerosis. METHODS AND RESULTS The prevalence of CAD among patients with paroxysmal or persistent AF and(More)
PURPOSE To examine magnetic resonance imaging (MRI) and computed tomography (CT) for lumpectomy cavity (LC) volume delineation in supine radiotherapy treatment position and to assess the interobserver variability. METHODS AND MATERIALS A total of 15 breast cancer patients underwent a planning CT and directly afterward MRI in supine radiotherapy treatment(More)
Purpose In left-sided breast cancer radiotherapy, tangential intensity modulated radiotherapy combined with breath-hold enables a dose reduction to the heart and left anterior descending (LAD) coronary artery. Aim of this study was to investigate the added value of intensity modulated proton therapy (IMPT) with regard to decreasing the radiation dose to(More)
PURPOSE To compare ultrasonography (US), computed tomography (CT), and palpation for diagnosing supraclavicular lung cancer metastases and to assess the effect of proved metastases on TNM stage and diagnostic work-up. MATERIALS AND METHODS One hundred seventeen consecutive patients (91 men and 26 women; mean age, 64.0 years) underwent palpation, US, and(More)