A Kluge

Kerckhoff Klinik, Stadt Bad Nauheim, Hesse, Germany

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Publications (41)118.91 Total impact

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    ABSTRACT: In a technical development study approved by the institutional ethics committee, the feasibility of fast diffusion-weighted imaging as a replacement for conventional magnetic resonance (MR) imaging sequences (short inversion time inversion recovery [STIR] and T1-weighted spin echo [SE]) and positron emission tomography (PET)/computed tomography (CT) in the detection of skeletal metastases from prostate cancer was evaluated. MR imaging and carbon 11 ((11)C) choline PET/CT data from 11 consecutive prostate cancer patients with bone metastases were analyzed. Diffusion-weighted imaging appears to be equal, if not superior, to STIR and T1-weighted SE sequences and equally as effective as (11)C-choline PET/CT in detection of bone metastases in these patients. Diffusion-weighted imaging should be considered for further evaluation and comparisons with PET/CT for comprehensive whole-body staging and restaging in prostate and other cancers.
    No preview · Article · Nov 2008 · Radiology
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    ABSTRACT: Radiation dose exposure is increased in multislice spiral computed tomography (MSCT) compared to conventional coronary angiography (CXA). Retrospective data analysis of 56 patients (66+/-8 years, 49 males, body surface area 1.98+/-0.18 m(2), heart rate 64+/-11 bpm) who underwent MSCT and CXA was performed (MSCT: 16-slice scanner, rotation time 0.375 s, 120 kV, ECG-pulsing; CXA: current technique system build in 2003). Ten patients with bypass grafts underwent bypass angiography in CXA and MSCT. To compare the radiation doses of both investigations, the effective dose (ED) was chosen as the analysis variable. The mean ED for MSCT was 9.76+/-1.84 mSv (n=46) for patients without bypass grafts; with calcium scoring the mean ED was 12.46+/-2.23 mSv (n=46). In comparison, the mean ED of CXA was 2.60+/-1.27 mSv (n=46) for patients without bypass grafts; with bypass grafts (n=10) the mean ED for MSCT was 12.95+/-1.75 mSv, for CXA of 6.27+/-4.04 mSv, respectively. In MSCT heart rates of <or=60 bpm resulted in lower mean ED than heart rates of >60 bpm (8.86+/-1.24 mSv versus 10.53+/-1.86 mSv). MSCT is still associated with a higher radiation dose exposure than CXA. The radiation dose relation is more favorable for MSCT than for CXA in patients with bypass grafts in comparison to patients without bypass grafts. This study emphasizes the importance of dose reduction techniques.
    No preview · Article · Mar 2008 · International journal of cardiology
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    ABSTRACT: To assess prospectively the agreement of magnetic resonance (MR) pulmonary perfusion with single-photon emission computed tomography (SPECT) perfusion for perfusion defects down to the subsegmental level in patients with suspected pulmonary embolism (PE). In 41 patients with suspected PE, contrast-enhanced MR pulmonary perfusion (3D-FLASH, TR/TE 1.6/0.6 ms) was compared to SPECT perfusion on a per-examination basis as well as at the lobar, segmental, and subsegmental level. The MRI protocol was completed in all patients, and mean examination time was 3 min 56 s. MR perfusion showed a very high agreement with SPECT (kappa value per examination 0.98, and 0.98, 0.83, and 0.69 for lobar, segmental, and subsegmental perfusion defects, respectively). Of 15 patients with PE, MR perfusion detected 14 cases. The very high agreement of MR perfusion with SPECT perfusion enables the detection of subtle findings in suspected PE.
    No preview · Article · Dec 2006 · Acta Radiologica
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    ABSTRACT: To compare three-dimensional (3D) power Doppler ultrasonography (PDUS) with contrast enhanced magnetic resonance imaging (MRI) in their capability to visualize synovial vascularity in inflamed wrists of patients with rheumatoid arthritis (RA). Nine patients with RA showing clinically active arthritis of the wrist as determined by tenderness and swelling were examined by contrast enhanced MRI and 3D PDUS. Vascularity close to and inside the joint capsule was visualized by conventional power Doppler mode. In a region with high Doppler signal intensity (=region of interest/ROI) a 3D blood vessel tree was obtained by a free-hand sweep. 3D images were evaluated with regard to the number of blood vessels in the intra- and peri-articular region. MRI examinations were performed using a 1.5 T Scanner. In MRI, time resolved coronal contrast enhanced T1-weighted sequences with fat suppression were acquired during an 8 min period to assess tissue enhancement. Relative enhancement was calculated and compared to 3D PDUS findings. A 3D vascular tree consisting of peri- and intra-articular blood vessels could be demonstrated in the same anatomical ROI in which an increased gadolinium enhancement was measured by MRI in all examined RA patients. The number of penetrating vessels into the joint capsule, the number of intra-articular vessels and a semiquantitative estimation of the strength of blood flow were used to generate a 3D score for the intensity of synovial vascularity. When compared with clinical symptoms and the gold standard dynamic MRI, 3D PDUS is a reliable imaging technique for assessing synovial vascularity in inflamed wrists of RA patients.
    No preview · Article · Nov 2006 · Joint, bone, spine: revue du rhumatisme
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    ABSTRACT: Objectif Comparer l'échographie-doppler de puissance à trois dimensions (EDP3D) et l'imagerie par résonance magnétique avec injection de contraste (IRM) pour visualiser la vascularisation synoviale dans le poignet rhumatoïde. Méthodes Les deux examens d'imagerie ont été réalisés chez neuf malades qui souffraient de polyarthrite rhumatoïde responsable au poignet de douleurs et d'une tuméfaction. La vascularisation intra- et péricapsulaire a été visualisée par doppler de puissance classique. Une région d'intérêt (RI) caractérisée par un signal doppler de forte intensité a été sélectionnée. Dans cette région, l'arbre vasculaire a été visualisé en 3D grâce à un balayage à main libre. Le nombre de vaisseaux dans les régions intra- et péricapsulaires sur les images en 3D a été déterminé. Une IRM avec injection de contraste a été réalisée avec un appareil de 1,5 Tesla. Des coupes frontales en résolution de temps, pondérées en T1, ont été obtenues au cours d'une période de huit minutes afin d'évaluer la prise de contraste tissulaire. La prise de contraste relative a été calculée et comparée aux résultats de l'EDP3D. Résultats Chez tous les malades, l'EDP3D a permis de visualiser un arbre vasculaire comportant des vaisseaux intra- et périarticulaires dans la région de prise de contraste en IRM. Nous avons déterminé un score 3D de vascularisation synoviale à partir du nombre de vaisseaux qui pénétraient dans la capsule, du nombre de vaisseaux intra-articulaires et d'une estimation semi quantitative du débit sanguin. Conclusion Par comparaison aux manifestations cliniques et à l'IRM dynamique, qui constitue la technique de référence, l'EDP3D permet une évaluation fiable de la vascularisation synoviale du poignet rhumatoïde.
    No preview · Article · Oct 2006 · Revue du Rhumatisme
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    Alexander Kluge · Wolfgang Luboldt · Georg Bachmann
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    ABSTRACT: The purpose of this study was to assess the individual and combined usefulness of MRI techniques in cases of acute pulmonary embolism and to compare the usefulness of these techniques with that of 16-MDCT. Sixty-two patients with symptoms indicating acute pulmonary embolism underwent an MRI protocol that progressed from real-time MRI through MR perfusion imaging to MR angiography. The results were compared with those of 16-MDCT, which was the reference standard. Thoracic incidental diagnoses other than pulmonary embolism also were sought with CT and MRI. Pulmonary embolism was diagnosed with CT in 19 patients for totals of 90 lobar, 245 segmental, and 434 subsegmental arteries. On a per-patient basis, the sensitivities of real-time MRI, MR angiography, MR perfusion imaging, and the combined protocol were 85%, 77%, 100%, and 100%, respectively. The specificities were 98%, 100%, 91%, and 93%. The kappa values in a comparison of the MR techniques with CT were 0.89, 0.87, 0.86, and 0.9. On a per-embolus basis, the sensitivities of real-time MRI, MR angiography, and MR perfusion imaging for lobar pulmonary embolism were 79%, 62%, and 100%. The sensitivities for segmental pulmonary embolism were 86%, 83%, and 97%, respectively. MR perfusion imaging had a sensitivity of 93% for subsegmental pulmonary embolism. Eight of nine incidental findings revealed on CT were also subsequently diagnosed with real-time MRI. MRI failed to reveal a case of emphysema. Mean MRI examination time was 9 minutes 56 seconds. The combined MR protocol is both reliable and sensitive in comparison with 16-MDCT in the diagnosis of pulmonary embolism. MR perfusion imaging is sensitive for the detection of pulmonary embolism, whereas real-time MR and MR angiography are specific.
    Preview · Article · Aug 2006 · American Journal of Roentgenology
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    ABSTRACT: The purpose of this study was to prospectively assess the feasibility and quality of combined MRI examinations consisting of thoracic MRI for suspected pulmonary embolism (PE) and MR venography for deep vein thrombosis (DVT), to assess the diagnostic yield of a combined examination for detecting thromboembolism compared with each component alone, and to retrospectively assess the concordance of duplex sonography and MR venography. Two hundred twenty-one consecutive patients (119 men, 102 women; mean age, 51 years; range, 31-86 years) with suspected PE were examined using a multitechnique thoracic MRI protocol (real-time MRI using true fast imaging with steady-state precession [FISP], perfusion MRI, and MR angiography) followed by stepping-table MR venography. Two hundred twenty-one thoracic MRI examinations were performed. Two hundred eighteen MR venography examinations were scheduled, of which five (2.3%) were not performed for clinical or technical reasons and six were not performed after negative thoracic MRI. Among 207 combined examinations, PE was diagnosed in 76 and DVT in 78 examinations. Thirteen patients without PE showed DVT; thus, MR venography detected 17% additional cases of thromboembolism. Agreement with duplex sonography was good at the upper leg (kappa = 0.87-0.89) but moderate at the pelvis (kappa = 0.59-0.65). A combined "one-stop-shopping" MRI approach for PE and DVT was routinely feasible and detected 17% more cases of thromboembolism compared with separate examinations. MRI may be considered a second-line technique to avoid contraindications to CT but also a primary comprehensive technique for diagnosing thromboembolism.
    No preview · Article · Jul 2006 · American Journal of Roentgenology
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    ABSTRACT: Without Abstract
    No preview · Article · Jan 2006 · Clinical Research in Cardiology
  • A Kluge · K Madlener · G Bachmann

    No preview · Article · Jan 2006 · RöFo - Fortschritte auf dem Gebiet der R

  • No preview · Article · Jan 2006 · RöFo - Fortschritte auf dem Gebiet der R
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    ABSTRACT: Ankylosing spondylitis (AS) is characterised by chronic inflammation and partial ossification, yet vertebral fractures due to osteoporosis, although common, are frequently unrecognised. The aim of this study was to (1) show the frequency of changes in the progress of osteopenia/osteoporosis in AS depending on duration and stage of the disease and (2) assess the ranking of two different methods of bone density measurement in this clinical pattern. We measured bone density in 84 male and female patients with both dual X-ray absorptiometry (DXA) and single energy quantitative computed tomography (SE-QCT). In the initial and advanced stages of the disease, a high decrease in axial bone density could be verified (DXA: osteopenia in 5% and osteoporosis in 9.2%; SE-QCT: osteopenia in 11.8% and osteoporosis in 30.3%). Peripheral bone density decrease as in osteopenia could be proven in 17.6% by DXA measurement. With SE-QCT, a decrease in vertebral trabecular bone density could already be observed in the initial stage and continued steadily during the course of the disease; cortical bone displayed the same trend up to stages of ankylosis. With DXA, valid conclusions are more likely to be expected in less marked ankylosing stages of AS. In stages of advanced ankyloses in the vertebral region (substantial syndesmophytes), priority should be given to SE-QCT, due to the selective measurement of trabecular and cortical bone. The DXA method often yields values that are too high, and the replacement of vertebral trabecular bone by fatty bone marrow is not usually recorded as standard. There may already be an increased risk of bone fracture in AS in osteopenia on DXA along with an osteoporosis already established on SE-QCT.
    No preview · Article · Dec 2005 · Rheumatology International
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    ABSTRACT: To retrospectively assess the indication for thoracic real-time MRI, demonstrate typical findings, analyze the diagnostic potential in subgroups with suspected pulmonary embolism (PE) and aortic dissection (AD), and describe the influence of real-time MRI on the role of MRI in acute thoracic diseases. From July 2001 to February 2005, real-time MRI was applied in 2,256 examinations in 1,714 patients. MRI was the primary diagnostic modality for these thoracic diseases as computed tomography has been available only since 2003. Characteristics of the TrueFISP sequence applied were: TR/TE/flip angle 3.1 ms/1.6 ms/59 degrees , respectively. FOV 340 - 360 mm, matrix size 156 to 192 x 256 pixels, slice thickness 3 to 4 mm, slices overlapped by 50 %. Acquisition time was 0.4 to 0.5 s per image. Three hundred and twenty transverse, coronal and sagittal images were acquired in three minutes. No breath holding, and only minimal patient cooperation, was required. Turbo-spin-echo sequences as well as ECG-gated and contrast-enhanced sequences were added depending on the indication. Most common indications were: acute thoracic nonspecified disease (n = 276, 12.24 %), PE (n = 573, 25.4 %), bleeding (n = 154, 6.8 %), AD (n = 222, 9.8 %), topographic information in complex findings (n = 654, 29.0 %). Real-time MRI was the sole MRI technique applied in 180 examinations (8.0 %), ECG-gated real-time MRI was applied in 87 examinations and breath hold was used in 107 examinations. PE was diagnosed in 181 examinations; reference techniques (MRI, computed tomography, single photon emission computed tomography) confirmed 170 of these and detected 19 more cases (sensitivity 90.0 %, specificity 97.1 %). Real-time MRI detected 141 suspected AD and 53 more nonsuspected AD. Of these, 191 were confirmed by other MRI techniques, surgery or clinical course (98.5 %). Real-time MRI coincidentally detected 56 pulmonary tumors, all were confirmed with computed tomography. Thus, especially vascular diseases could be easily assessed with real-time MRI, while computed tomography had advantages in the evaluation of the lung parenchyma. Real-time MRI both enables emergency MRI examinations for thoracic diseases in clinical patients in unstable condition and allows an explorative style of working in patients with nondefined acute thoracic diseases.
    No preview · Article · Dec 2005 · RöFo - Fortschritte auf dem Gebiet der R
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    ABSTRACT: Pulmonary vein stenosis (PVS) is a potential complication of pulmonary vein isolation (PVI) using radiofrequency energy. The aim of our study was the evaluation of the severity and long-term outcome of primary angioplasty and angioplasty with pulmonary vein stenting for PVS. Twelve patients with 15 PVS (greater than 70% stenosis) were prospectively evaluated. Primary dilation of the stenosis was performed because of clinical symptoms (10 patients) and/or the lung perfusion scans showed a significant perfusion defect (11 patients). Magnetic resonance imaging and lung perfusion scans performed before, directly after, during 3-month, and 6-month follow-up. In the stenting group additional multislice CT-scans directly after, during 6-month, and 12-month follow-up were performed. Within 2 months after primary balloon angioplasty, the PV size parameters were significantly reduced (P < 0.001) with recurrence of PVS in 11 of 15 PVs (73%). Pulmonary vein stenting in 8 patients and 11 PVs resulted in no vein stenosis during 12-month follow-up. Normalization of lung perfusion was noted in 8 of 12 patients. We observed 2 patients with hemoptysis during PV dilation, as severe complications with potential life-threatening character. PVS stenting seems to be superior to balloon angioplasty and effective at least over a period of 12 months in treating acquired PVS after pulmonary vein isolation.
    No preview · Article · Nov 2005 · Journal of Cardiovascular Electrophysiology
  • Alexander Kluge · Tibo Gerriets · Uwe Lange · George Bachman
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    ABSTRACT: Tha aim of this study was to demonstrate the feasibility of MRI for short-term follow-up examinations in patients with acute pulmonary embolism (PE), and to assess temporal changes of pulmonary perfusion and thrombus characteristics that may be helpful in determining thrombus age. Thirty-three patients (15 female, 18 male, mean age 59.4 years) with acute PE were examined initially and 1 week later using both 16-row computed tomography (CT) and MRI with magnetic resonance angiography (MRA), real-time MRI and magnetic resonance (MR) pulmonary perfusion imaging. MRA and MR pulmonary perfusion used contrast-enhanced 3D flash sequences, and real-time MRI used true fast imaging with steady-state precession sequences (repetition time/echo time 3.1/1.5, bandwidth 975 Hz, 256 matrix size, acquisition time 0.4 s per image) in three orthogonal planes. Follow-up examinations were feasible for all patients. Diagnosis of PE was concordant between MRI and CT in all patients. The signal intensity of embolic material increased after 1 week for real-time MRI [132+/-5 vs. 232+/-22 (standard error of the mean), p<0.001], but not significantly for MRA. MR pulmonary perfusion of areas affected by PE increased (area under the curve initially 9.6+/-7.4, at follow-up 40.7+/-7.6, p<0.001). A decreasing time-to-peak in normal lung areas (15.7+/-0.96 and 13.2+/-0.55, respectively, p<0.05) indicated systemic circulatory effects of PE, and subsiding pulmonary artery obstruction improved arterial inflow for the entire lung. Follow-up examinations of patients with acute PE are feasible with MRI, and a relation between thrombus appearance and thrombus age can be implied.
    No preview · Article · Oct 2005 · European Radiology

  • No preview · Article · May 2005 · RöFo - Fortschritte auf dem Gebiet der R
  • F Bachmann · T Dill · A Kluge · M Weber · CW Hamm

    No preview · Article · May 2005 · RöFo - Fortschritte auf dem Gebiet der R

  • No preview · Article · May 2005 · RöFo - Fortschritte auf dem Gebiet der R
  • F Bachmann · E Basad · A Kluge · D Lommel · J Steinmeyer

    No preview · Article · May 2005 · RöFo - Fortschritte auf dem Gebiet der R
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    ABSTRACT: MRI proved to be a valuable tool for the evaluation and monitoring of myocarditis. We report the case of a 36 year old caucasian male with an undifferentiated collagenosis who presented first four years ago with unspecific symptoms and impaired exercise capacity. On echocardiography left ventricular function was impaired as well as on MRI. In addition, after administration of Gd-DTPA an intramyocardial pathological signal enhancement was observed on TSE T1 weighted and contrast enhanced FLASH 3D IR sequences. Based on several diagnostic tests including myocardial biopsy an autoimmune myocarditis due to an undifferentiated collagenosis was diagnosed. On long time follow up over almost 3 years with repeated MRI examinations, the delayed hyper enhancement (dHE) decreased or disappeared with successful treatment, respectively. However, in the area of recurrent inflammation, a persisting area of dHE developed with a subsequent perfusion defect. This area represents myocardial fibrosis due to recurrent inflammation.
    Preview · Article · Feb 2005 · Journal of Cardiovascular Magnetic Resonance

  • No preview · Article · Jan 2005 · RöFo - Fortschritte auf dem Gebiet der R

Publication Stats

927 Citations
118.91 Total Impact Points


  • 2005-2006
    • Kerckhoff Klinik
      • • Department of Diagnostic Radiology
      • • Department of Cardiology
      Stadt Bad Nauheim, Hesse, Germany
  • 1997-2006
    • Justus-Liebig-Universität Gießen
      • • Department of Internal Medicine
      • • Abteilung für Psychologische Diagnostik
      Gieben, Hesse, Germany
  • 2002
    • Philipps University of Marburg
      Marburg, Hesse, Germany