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  • LUNG  (19)
  • MOTION  (8)
  • DIAGNOSIS  (6)
  • RESOLUTION  (6)
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  • 11
    Keywords: Germany ; LUNG ; PERFUSION ; THERAPY ; CT ; imaging ; PATIENT ; MRI ; SEQUENCE ; MAGNETIC-RESONANCE ; magnetic resonance imaging ; AGE ; STATISTICAL-ANALYSIS ; MORPHOLOGY ; PULMONARY PERFUSION ; BODY ; CHILDREN ; SEGMENTS ; FEASIBILITY ; BREATH-HOLD ; LUNG PERFUSION ; fibrosis ; WEIGHT ; IMPAIRMENT ; CYSTIC-FIBROSIS ; cystic fibrosis ; SMALL AIRWAYS ; DEFECT ; GRAPPA ; CIRCULATION ; lung morphology
    Abstract: This paper is a feasibility study of magnetic resonance imaging (MRI) of lung perfusion in children with cystic fibrosis (CF) using contrast-enhanced 3D MRI. Correlation assessment of perfusion changes with structural abnormalities. Eleven CF patients (9 f, 2 m; median age 16 years) were examined at 1.5 T. Morphology: HASTE coronal, transversal (TR/TE/alpha/ST: 600 ms/28 ms/180 degrees/6 mm), breath-hold 18 s. Perfusion: Time-resolved 3D GRE pulse sequence (FLASH, TE/TR/alpha: 0.8/1.9 ms/40 degrees), parallel imaging (GRAPPA, PAT 2). Twenty-five data sets were acquired after intravenous injection of 0.1 mmol/kg body weight of gadodiamide, 3-5 ml/s. A total of 198 lung segments were analyzed by two radiologists in consensus and scored for morphological and perfusion changes. Statistical analysis was performed by Mantel-Haenszel chi-square test. Results showed that perfusion defects were observed in all patients and present in 80% of upper, and 39% of lower lobes. Normal lung parenchyma showed homogeneous perfusion (86%, P 〈 0.0001). Severe morphological changes led to perfusion defects (97%, P 〈 0.0001). Segments with moderate morphological changes showed normal (53%) or impaired perfusion (47%). In conclusion, pulmonary perfusion is easy to judge in segments with normal parenchyma or severe changes. In moderately damaged segments, MRI of lung perfusion may help to better assess actual functional impairment. Contrast-enhanced 3D MRI of lung perfusion has the potential for early vascular functional assessment and therapy control in CF patients
    Type of Publication: Journal article published
    PubMed ID: 16673092
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  • 12
    Keywords: Germany ; LUNG ; chest ; CT ; DIAGNOSIS ; FOLLOW-UP ; imaging ; DISEASE ; EXPOSURE ; RESOLUTION ; radiation ; PATIENT ; IMPACT ; prognosis ; MRI ; MAGNETIC-RESONANCE ; magnetic resonance imaging ; MORPHOLOGY ; COMPUTED-TOMOGRAPHY ; FUNCTION TESTS ; magnetic resonance imaging (MRI) ; CHILDREN ; HRCT ; fibrosis ; ADULTS ; LIFE ; CYSTIC-FIBROSIS ; TESTS ; technique ; function ; cystic fibrosis ; RADIATION EXPOSURE ; lungs ; improvement of ; gold ; mucoviscidosis
    Abstract: Cystic fibrosis (CF) is a multi-systemic disease with major impact on the lungs. Pulmonary manifestation is crucial for the prognosis and life expectancy of patients. Imaging modalities and lung function tests reflect the pulmonary status in these patients. The standard imaging modality for diagnosis and follow-up of pulmonary changes is chest x-ray. The gold standard for the detection of parenchymal lung changes remains high resolution computed tomography (HRCT), but this is not used routinely for CF-patients due to radiation exposure. Magnetic resonance imaging (MRI) used to be of no importance in monitoring cystic fibrosis lung disease, as shown in studies from the 1980s and early 1990s. The continuing improvement of MRI techniques, however, has allowed for an adequate application of this non-radiation method in diagnosing the major pulmonary findings in CF, in addition to the assessment of lung function
    Type of Publication: Journal article published
    PubMed ID: 16437239
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  • 13
  • 14
    Keywords: Germany ; LUNG ; DIAGNOSIS ; segmentation ; DISEASE ; RESOLUTION ; TRANSPLANTATION ; MRI ; MAGNETIC-RESONANCE ; magnetic resonance imaging ; prevention ; MOTION ; dynamic MRI ; MANAGEMENT ; MOVEMENT ; SCIENCE ; breathing cycle ; HEALTHY-SUBJECTS ; SPIROMETRY ; volumetry ; RESPIRATORY MOTION ; MR-compatible spirometry ; respiratory mechanics ; GLOBAL STRATEGY
    Abstract: Rationale and Objectives: Most lung disease is inhomogeneously distributed but diagnosed by global spirometry. Regional lung function might allow for earlier diagnosis. Dynamic two-dimensional magnetic resonance imaging (2D-MRI) can depict lung motion with high temporal resolution. We evaluated whether measurement of lung area on dynamic 2D-MRI has sufficient agreement with spirometry to allow for lung function testing of single lungs. Material and Methods: Ten healthy volunteers were examined in a 1.5 T MRI scanner with a Flash 2D-sequence (8.5 images per second, sagittal and coronal orientation) with simultaneous spirometry. The lung area was segmented semiautomatically and the area changes were compared with spirometric volume changes. Results: Segmentation of one time series took 191 seconds on average. Volume-time and flow-volume curves from MRI data were almost congruent with spirometric curves. Pearson correlation of MRI area with spirometry was very high (mean correlation coefficients 〉0.97). Bland-Altman plots showed good agreement of lung area with spirometry (95% limits of agreement below 11% in each direction). Differences between lung area and spirometry were significantly smaller for sagittal measurement of the right lung than sagittal measurement of the left lung and coronal measurement. The relative forced expiratory volume in the first second differed less than 5% between MRI and spirometry in all but one volunteer. Conclusions: Measurement of lung area on 2D-MRI allows for functional measurement of single lungs with good agreement to spirometry. Postprocessing is fast enough for application in a clinical context and possibly provides increased sensitivity for lung functional measurement of inhomogeneously distributed lung disease
    Type of Publication: Journal article published
    PubMed ID: 20138554
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  • 15
    Keywords: radiotherapy ; EXPERIENCE ; POSITRON-EMISSION-TOMOGRAPHY ; HEAD ; MOTION ; CONTRAST-ENHANCED MRI ; NECK-CANCER ; TUMOR HYPOXIA ; F-18 FLUOROMISONIDAZOLE ; TERM SURVIVAL
    Abstract: ABSTRACT: BACKGROUND: Radiotherapy, preferably combined with chemotherapy, is the treatment standard for locally advanced, unresectable non-small cell lung cancer (NSCLC). The tumor response to different therapy protocols is variable, with hypoxia known to be a major factor that negatively influences treatment effectiveness. Visualisation of tumor hypoxia prior to the use of modern radiation therapy strategies, such as intensity modulated radiation therapy (IMRT), might allow optimized dose applications to the target volume, leading to improvement of therapy outcome. 18 F-fluoromisonidazole dynamic positron emission tomography and computed tomography (18 F-FMISO dPET-CT) and functional magnetic resonance imaging (functional MRI) are attractive options for imaging tumor hypoxia.Methods/designThe HIL trial is a single centre study combining multimodal hypoxia imaging with 18 F-FMISO dPET-CT and functional MRI, with intensity modulated radiation therapy (IMRT) in patients with inoperable stage III NSCLC. 15 patients will be recruited in the study. All patients undergo initial FDG PET-CT and serial 18 F-FMISO dPET-CT and functional MRI before treatment, at week 5 of radiotherapy and 6 weeks post treatment. Radiation therapy is performed as inversely planned IMRT based on 4D-CT. DISCUSSION: Primary objectives of the trial are to characterize the correlation of 18 F-FMISO dPET-CT and functional MRI for tumor hypoxia imaging in NSCLC and evaluate possible effects of radiation therapy on tumor re-oxygenation. Further objectives include the generation of data regarding the prognostic value of 18 F-FMISO dPET-CT and functional MRI for locoregional control, progression free survival and overall survival of NSCLC treated with IMRT, which will form the basis for larger clinical trials focusing on possible interactions between tumor oxygenation and radiotherapy outcome.Trial registrationThe ClinicalTrials.gov protocol ID is NCT01617980.
    Type of Publication: Journal article published
    PubMed ID: 22974533
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  • 16
  • 17
    Keywords: Germany ; LUNG ; PERFUSION ; CT ; DIAGNOSIS ; IMAGES ; VISUALIZATION ; DISEASE ; DIFFERENTIATION ; RESOLUTION ; TIME ; PATIENT ; MR ; MRI ; MAGNETIC-RESONANCE ; arteries ; EMBOLISM ; MR-ANGIOGRAPHY ; magnetic resonance angiography ; pathology ; ANGIOGRAPHY ; HYPERTENSION ; contrast media ; MANAGEMENT ; PULMONARY ; PH ; ARTERIAL-HYPERTENSION ; ARTERIAL ; LEVEL ; IMAGE QUALITY ; CONSENSUS ; PULMONARY-ARTERIES ; TEMPORAL RESOLUTION ; HIGH-SPATIAL-RESOLUTION ; CTEPH ; IPAH
    Abstract: Differentiation between different forms of pulmonary hypertension (PH) is essential for correct disease management. The goal of this study was to elucidate the clinical impact of high spatial resolution MR angiography (SR-MRA) and time-resolved MRA (TR-MRA) to differentiate between patients with chronic thromboembolic PH (CTEPH) and idiopathic pulmonary arterial hypertension (IPAH). Ten PH patients and five volunteers were examined. Twenty TR-MRA data sets (TA 1.5 s) and SR-MRA (TA 23 s) were acquired. TR-MRA data sets were subtracted as angiography and perfusion images. Evaluation comprised analysis of vascular pathologies on a segmental basis, detection of perfusion defects, and bronchial arteries by two readers in consensus. Technical evaluation comprised evaluation of image quality, signal-to-noise ratio (SNR) measurements, and contrast-media passage time. Visualization of the pulmonary arteries was possible down to a subsegmental (SR-MRA) and to a segmental (TR-MRA) level. SR-MRA outperformed TR-MRA in direct visualization of intravascular changes. Patients with IPAH predominantly showed tortuous pulmonary arteries while in CTEPH wall irregularities and abnormal proximal-to-distal tapering was found. Perfusion images showed a diffuse pattern in IPAH and focal defects in CTEPH. TR-MRA and SR-MRA resulted in the same final diagnosis. Both MRA techniques allowed for differentiation between IPAH and CTEPH. Therefore, TR-MRA can be used in the clinical setting, especially in dyspneic patients
    Type of Publication: Journal article published
    PubMed ID: 16041529
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  • 18
    Keywords: BLOOD ; Germany ; LUNG ; SPIRAL CT ; VOLUME ; DISEASE ; POPULATION ; HEART ; TIME ; PATIENT ; BLOOD-FLOW ; blood flow ; FLOW ; MRI ; MAGNETIC-RESONANCE ; magnetic resonance imaging ; AGE ; arteries ; PARAMETERS ; HYPERTENSION ; HEALTHY ; PULMONARY ; VELOCITY ; fibrosis ; PH ; HEALTHY-VOLUNTEERS ; CHRONIC THROMBOEMBOLISM ; CYSTIC-FIBROSIS ; ARTERIAL ; PULMONARY-ARTERIES ; early development ; bronchosystemic shunt ; cystic fibrosis
    Abstract: Cystic fibrosis (CF) leads to disabling lung disease and pulmonary hypertension (PH). The goal of this study was to assess the hemodynamics in the systemic and pulmonary arterial circulation of patients with CF using MRI. Ten patients with CF and 15 healthy volunteers were examined (1.5-T MRI). Phase-contrast flow measurements were assessed in the ascending aorta, pulmonary trunc, and the left and right pulmonary arteries (PA), resulting in the following parameters: peak velocity (PV) (centimeters per second) velocity rise gradient (VRG), time to PV (milliseconds), and the average area (centimeters squared). The blood flow ratio between the right and left lungs and the bronchosystemic shunt were calculated. For the ascending aorta and pulmonary trunc no parameter was significantly different between both populations. In the right PA a significantly lower PV (p=0.001) and VRG (p=0.02) was found. In the left PA there was a significantly (p=0.007) lower PV but no significant (p=0.07) difference between the VRG. The areas of the right (p=0.08) and left (p=0.5) PA were not significantly enlarged. For the volunteers a linear increase of PV in both PA was found with age, while it decreased in patients with CF. The blood flow distribution (right/left lung) showed no significant (p=0.7) difference between the groups. There was a significantly (p 〈 0.001) higher bronchosystemic shunt volume in patients with CF (1.3 l/min) than in volunteers (0.1 l/min). Magnetic resonance based flow measurements in the right and left PA showed first indications for early development of PH. The significant increase in bronchosystemic shunt volume might be indicative fo the extent of parenchymal changes
    Type of Publication: Journal article published
    PubMed ID: 15761712
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  • 19
    Keywords: COMBINATION ; Germany ; LUNG ; MODEL ; PERFUSION ; EMPHYSEMA ; IMAGES ; imaging ; TOOL ; VOLUME ; DISEASE ; MRI ; CYCLE ; SEQUENCE ; MAGNETIC-RESONANCE ; magnetic resonance imaging ; REGION ; COMPUTED-TOMOGRAPHY ; MOTION ; HEALTHY ; RE ; HEALTHY-VOLUNTEERS ; CHEST-WALL ; PULMONARY-FUNCTION TESTS ; HUMAN DIAPHRAGM SHAPE ; breathing cycle ; HEALTHY-SUBJECTS ; lung motion ; SPIROMETRY ; view sharing ; volumetry ; dynamic 3D MRI ; respiration
    Abstract: Rationale and Objectives: We sought to investigate lung volume and surface measurements during the breathing cycle using dynamic three-dimensional magnetic resonance imaging (3D MRI). Materials and Methods: Breathing cycles of 20 healthy volunteers were examined using a 2D trueFISP sequence (3 images/second) in combination with a model and segmented 3D FLASH sequence (1 image/second) MR images using view sharing. Segmentation was performed semiautomatically using an interactive region growing technique. Vital capacity (VC) was calculated from MRI using the model (2D) and counting the voxels (3D) and was compared with spirometry. Results: VC from spirometry was 4.9 +/- 0.9 L, 4.4 +/- 1.2 L from 2D MRI measurement, and 4.7 +/- 0.9 L for 3D MRI. Using the 3D technique, correlation to spirometry was higher than using the 2D technique (r 〉 0.95 vs. r 〉 0.83). Using the 3D technique, split lung volumes and lung surface could be calculated. There was a significant difference between the left and right lung volume in expiration (P 〈 0.05). Conclusions: Dynamic 3D MRI is a noninvasive tool to evaluate split lung volumes and lung surfaces during the breathing cycle with a high correlation to spirometry
    Type of Publication: Journal article published
    PubMed ID: 15714092
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  • 20
    Keywords: Germany ; DISEASE ; PATIENT ; MRI ; CYCLE ; MOBILITY ; REPRODUCIBILITY ; FUNCTION TESTS ; THIN-SECTION CT ; MOTION ; HYPERTENSION ; dynamic MRI ; BREATH-HOLD ; DIAPHRAGM ; LEVEL ; INTERVAL ; INTRATHORACIC TUMOR ; healthy subjects ; LUNG-VOLUME ; primary pulmonary hypertension
    Abstract: To assess the stability and reproducibility of different breath-hold levels in healthy volunteers and patients using dynamic MRI (dMRI). In ten healthy volunteers and ten patients with pulmonary hypertension (PH) and normal lung function craniocaudal intrathoracic distances (CCD) were measured during inspiratory and expiratory breath-hold (15 s) (in healthy volunteers additionally at a self-chosen mid-inspiratory breath-hold) using dMRI (trueFISP, three images/s). To evaluate stability and intraobserver reproducibility of the different breath-hold levels, CCDs, time-distance curves, confidence intervals (CIs), Mann-Witney U test and regression equations were calculated. In healthy volunteers there was a substantial decrease of the CCD during the inspiratory breath-hold in contrast to the expiratory breath-hold. The CI at inspiration was 2.84 +/- 1.28 in the right and 2.1 +/- 0.68 in the left hemithorax. At expiration the CI was 2.54 +/- 1.18 and 2.8 +/- 1.48. Patients were significantly less able to hold their breath at inspiration than controls (P 〈 0.05). In patients CI was 4.53 +/- 4.06 and 3.46 +/- 2.21 at inspiration and 4.45 +/- 4.23 and 4.76 +/- 3.73 at expiration. Intraobserver variability showed no significant differences either in patients or in healthy subjects. Reproducibility was significantly lower at a self-chosen breath-hold level of the healthy volunteers. DMRI is able to differentiate stability and reproducibility of different breath-hold levels. Expiratory breath-hold proved to be more stable than inspiratory breath-hold in healthy volunteers and patients
    Type of Publication: Journal article published
    PubMed ID: 15968516
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