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  • HEALTHY-VOLUNTEERS  (6)
  • 1
    Keywords: measurement ; tumor ; Germany ; LUNG ; CT ; IMAGES ; DISEASE ; NEW-YORK ; TUMORS ; PATIENT ; REDUCTION ; CONTRAST ; MRI ; CYCLE ; SEQUENCE ; NO ; DIFFERENCE ; REGION ; LOCALIZATION ; LENGTH ; COMPUTED-TOMOGRAPHY ; CURVES ; 3-DIMENSIONAL RECONSTRUCTION ; MOTION ; HEALTHY ; ORIENTATION ; LOCATION ; dynamic MRI ; ADULT ; ADULTS ; STRENGTH ; TRUEFISP ; HEALTHY-VOLUNTEERS ; PULMONARY-FUNCTION ; HEART-FAILURE ; EXPIRATION ; LUNG-VOLUMES ; breathing cycle ; diaphragmatic function
    Abstract: The purpose of this study was to assess diaphragmatic length and shortening during the breathing cycle in healthy volunteers and patients with a lung tumor using dynamic MRI (dMRI). In 15 healthy volunteers and 28 patients with a solitary lung tumor, diaphragmatic motion and length were measured during the breathing cycle using a trueFISP sequence (three images per second in the coronal and sagittal plane). Time-distance curves and maximal length reduction (= shortening) of the diaphragm were calculated. The influence of tumor localization on diaphragmatic shortening was examined. In healthy volunteers maximal diaphragmatic shortening was 30% in the coronal and 34% in the sagittal orientation, with no difference between both hemithoraces. Tumors of the upper and middle lung region did not affect diaphragmatic shortening. In contrast, tumors of the lower lung region changed shortening significantly (P〈0.05). In hemithoraces with a tumor in the lower region, shortening was 18% in the coronal and 19% in the sagittal plane. The ratio of diaphragmatic length change from inspiration to expiration changed significantly from healthy subjects (inspiration length &MGT; expiratory length, P〈0.05) to patients with a tumor in the lower lung region (inspiratory length = expiratory length). dMRI is a simple, non-invasive method to evaluate diaphragmatic motion and shortening in volunteers and patients during the breathing cycle. Tumors of the lower lung region have a significant influence on shortening of the diaphragm
    Type of Publication: Journal article published
    PubMed ID: 15127220
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  • 2
    Keywords: BLOOD ; Germany ; LUNG ; PERFUSION ; imaging ; QUANTIFICATION ; VOLUME ; TIME ; BLOOD-FLOW ; blood flow ; FLOW ; HIGH-RESOLUTION MEASUREMENT ; MRI ; TRACER BOLUS PASSAGES ; MAGNETIC-RESONANCE ; magnetic resonance imaging ; AGE ; PARAMETERS ; SCINTIGRAPHY ; CONTRAST-ENHANCED MRI ; magnetic resonance imaging (MRI) ; QUANTITATIVE-ANALYSIS ; HEALTHY ; LUNG PERFUSION ; TRANSIT-TIME ; HEALTHY-VOLUNTEERS ; ARTERIAL ; INFLATION ; contrast-enhanced
    Abstract: Rationale and Objectives: The effect of breathholding on pulmonary perfusion remains largely unknown. The aim of this study was to assess the effect of inspiratory and expiratory breathhold on pulmonary perfusion using quantitative pulmonary perfusion magnetic resonance imaging (MRI). Methods and Results: Nine healthy volunteers (median age, 28 years; range, 20-45 years) were examined with contrast-enhanced time-resolved 3-dimensional pulmonary perfusion MRI (FLASH 313, TR/TE: 1.9/0.8 ms; flip angle: 40degrees; GRAPPA) during end-inspiratory and expiratory breathholds. The perfusion parameters pulmonary blood flow (PBF), pulmonary blood volume (PBV), and mean transit time (MTT) were calculated using the indicator dilution theory. As a reference method, end-inspiratory and expiratory phase-contrast (PC) MRI of the pulmonary arterial blood flow (PABF) was performed. Results: There was a statistically significant increase of the PBF (Delta = 182 mL/100mL/min), PBV (Delta = 12 mL/100 mL), and PABF (Delta = 0.5 L/min) between inspiratory and expiratory breathhold measurements (P 〈 0.0001). Also, the MTT was significantly shorter (Delta = -0.5 sec) at expiratory breathhold (P = 0.03). Inspiratory PBF and PBV showed a moderate correlation (r = 0.72 and 0.61, P less than or equal to0.008) with inspiratory PABF. Conclusion: Pulmonary perfusion during breathhold depends on the inspiratory level. Higher perfusion is observed at expiratory breathhold
    Type of Publication: Journal article published
    PubMed ID: 15654250
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  • 3
    Keywords: BLOOD ; Germany ; LUNG ; QUANTIFICATION ; TIME ; BLOOD-FLOW ; blood flow ; FLOW ; MRI ; PATTERNS ; PARAMETERS ; HYPERTENSION ; BLOOD-FLOW MEASUREMENTS ; BREATH-HOLD ; ENCODED CINE MRI ; HEMODYNAMICS ; RE ; HEALTHY-VOLUNTEERS ; phase-contrast MRI ; pulmonary circulation ; systemic circulation ; VENTRICULAR STROKE VOLUME
    Abstract: OBJECTIVE. The purpose of this study was to use phase-contrast MRI to evaluate the influence of various breathing maneuvers on the hemodynamics of the pulmonary and systemic arterial circulation. SUBJECTS AND METHODS. Twenty-five volunteers were examined with phase-contrast MRI. Flow measurements were acquired in the aorta, pulmonary trunk, and left and right pulmonary arteries during deep, large-volume inspiratory breath-hold, expiratory breath-hold, and smooth respiration (no breath-hold). Parameters assessed were peak velocity, blood flow, velocity gradient, and acceleration time. RESULTS. Pulmonary blood flow and peak velocity were significantly reduced during inspiratory breath-hold and expiratory breath-hold compared with no breath-hold (p 〈 0.01). Pulmonary velocity gradient in inspiratory breath-hold was significantly (p:! 0.01) lower than in expiratory breath-hold and no breath-hold. There was no difference in velocity gradient between expiratory breath-hold and no breath-hold. Peak velocity in the aorta was lowest with no breath-hold. Velocity gradient was highest in expiratory breath-hold, and no breath-hold had the smallest SD. Acceleration time in the pulmonary trunk showed no difference between inspiratory breath-hold, expiratory breath-hold, and no breath-hold. Blood flow distribution to the left (45-47%) and to the right (53-55%) lung was not influenced by breathing maneuver. CONCLUSION. Measurements during smooth respiration showed the smallest SD. Therefore, no-breath-hold measurements should be considered for assessment of hemodynamics in clinical practice
    Type of Publication: Journal article published
    PubMed ID: 16861549
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  • 4
    Keywords: CANCER ; tumor ; carcinoma ; Germany ; LUNG ; imaging ; lung cancer ; LUNG-CANCER ; VOLUME ; TUMORS ; RESOLUTION ; PATIENT ; MRI ; SEQUENCE ; MAGNETIC-RESONANCE ; magnetic resonance imaging ; REGION ; LOCALIZATION ; LENGTH ; PARAMETERS ; FUNCTION TESTS ; 3-DIMENSIONAL RECONSTRUCTION ; MOTION ; HEALTHY ; COMPLICATIONS ; dynamic MRI ; STAGE-I ; HEALTHY-VOLUNTEERS ; PULMONARY-FUNCTION ; HUMAN DIAPHRAGM SHAPE ; breathing cycle ; HEALTHY-SUBJECTS ; SPIROMETRY ; parallel imaging ; TEMPORAL RESOLUTION ; IA ; FEV1 /VC ; INTRATHORACIC TUMOR
    Abstract: Purpose: To assess relative forced expiratory volume in one second (FEV1/vital capacity (VQ in healthy subjects and patients with a lung tumor using dynamic magnetic resonance imaging (dMRI) parameters. Materials and Methods: In 15 healthy volunteers and 31 patients with a non-small-cell lung carcinoma stage I (NSCLC 1), diaphragmatic length change (LEI) and craniocaudal (CC) intrathoracic distance change within one second; from maximal inspiration (DEI) were divided by total length change (LEtotal, DEtotal) as a surrogate of spirometric FEV 1 /VC using a true fast imaging with steady-state precession (trueFISP) sequence TE/TR = 1.7/37.3 msec, temporal resolution = 3 images/second). Influence of tumor localization was examined. Results: In healthy volunteers FEV I /VC showed a highly significant correlation with LE1/LEtotal and DE1/DEtotal (r 〉 0.9. P 〈 0.01). In stage IB tumor patients, comparing tumor-bearing with the non-tumor-bearing hemithorax, there,was a significant difference in tumors of the middle (LE1 /LEtotal= 0.63 +/- 0.05 vs. 0. 73 +/- 0.04, DE1/DEtotal= 0.66 +/- 0.05 vs. 0.72 +/- 0.04; P 〈 0.05) and lower (P 〈 0.05) lung region. Stage IA tumor patients showed no significant differences with regard to healthy subjects. Conclusion: dMRI is a simple noninvasive method to locally determine LE1 /LEtotal and DE1 /DEtotal as a surrogate of FEV1/VC in volunteers and patients. Tumors of the middle and lower lung regions have a significant influence on these MRI parameters
    Type of Publication: Journal article published
    PubMed ID: 15723381
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  • 5
    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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  • 6
    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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