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  • MAGNETIC-RESONANCE  (13)
  • MOTION  (8)
  • AGE  (6)
  • DIAGNOSIS  (6)
  • RESOLUTION  (6)
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  • 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: measurement ; CANCER ; radiotherapy ; tumor ; Germany ; LUNG ; IMAGES ; lung cancer ; LUNG-CANCER ; TISSUE ; TUMORS ; PATIENT ; MRI ; CYCLE ; SEQUENCE ; STAGE ; RADIATION-THERAPY ; MOBILITY ; REGION ; REGIONS ; WALL ; CURVES ; MOTION ; FUTURE ; LINEAR-ACCELERATOR ; LOCATION ; dynamic MRI ; TRUEFISP ; PULMONARY-FUNCTION ; EXTERNAL-BEAM RADIOTHERAPY ; breathing cycle ; CT SCANS ; DIAPHRAGM ; HEALTHY-SUBJECTS ; lung MRL radiotherapy ; tumor diameter
    Abstract: Background and purpose: To assess the influence of tumor diameter on tumor mobility and motion of the tumor bearing hemithorax during the whole breathing cycle in patients with stage I non-small-cell lung cancer (NSCLC) using dynamic MRI. Patients and methods: Breathing cycles of thirty-nine patients with solitary NSCLCs were examined using a trueFISP sequence (three images per second). Patients were divided into three groups according to the maximal tumor diameter in the transverse plane ( 〈3, 3-5 and 〉5 cm). Continuous time-distance curves and deep inspiratory and expiratory positions of the chest wall, the diaphragm and the tumor were measured in three planes. Motion of tumor-bearing and corresponding contralateral non-tumor bearing regions was compared. Results: Patients with a tumor 〉3 cm showed a significantly lower diaphragmatic motion of the tumor bearing compared with the non-tumor bearing hemithorax in the craniocaudal (CC) directions (tumors 3-5 cm: 23.4 +/- 1.2 vs 21.1 +/- 1.5 cm (P 〈0.05); tumors 〉5 cm: 23.4 +/- 1.2 vs 20.1 +/- 1.6 cm (P 〈0.01). Tumors 〉5 cm in the lower lung region showed a significantly lower mobility compared with tumors 〈3 cm (1.8 +/- 1.0 vs 3.8 +/- 0.7 cm, P 〈0.01) in the CC directions. Conclusions: Dynamic MRI is a simple non-invasive method to differentiate mobility of tumors with different diameters and its influence on the surrounding tissue. Tumor diameter has a significant influence on tumor mobility and this might be taken into account in future radiotherapy planning, (C) 2004 Elsevier Ireland Ltd. All rights reserved
    Type of Publication: Journal article published
    PubMed ID: 15588881
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  • 3
    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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  • 4
    Keywords: CANCER ; DIAGNOSIS ; PERFORMANCE ; REPRODUCIBILITY ; HELICAL CT ; IMAGE QUALITY ; volumetry ; CHEST CT ; RADIOLOGISTS DETECTION ; CAD SOFTWARE
    Abstract: OBJECTIVES: To evaluate the influence of exposure parameters and raw-data based iterative reconstruction (IR) on the performance of computer-aided detection (CAD) of pulmonary nodules on chest multidetector computed tomography (MDCT). MATERIAL AND METHODS: Seven porcine lung explants were inflated in a dedicated ex vivo phantom shell and prepared with n=162 artificial nodules of a clinically relevant volume and maximum diameter (46-1063mul, and 6.2-21.5mm). n=118 nodules were solid and n=44 part-solid. MDCT was performed with different combinations of 120 and 80kV with 120, 60, 30 and 12mA*s, and reconstructed with both filtered back projection (FBP) and IR. Subsequently, 16 datasets per lung were subjected to dedicated CAD software. The rate of true positive, false negative and false positive CAD marks was measured for each reconstruction. RESULTS: The rate of true positive findings ranged between 88.9-91.4% for FBP and 88.3-90.1% for IR (n.s.) with most exposure settings, but was significantly lower with the combination of 80kV and 12mA*s (80.9% and 81.5%, respectively, p〈0.05). False positive findings ranged between 2.3 - 8.1 annotations per lung. For nodule volumes 〈200mul the rate of true positives was significantly lower than for 〉300mul (p〈0.05). Similarly, it was significantly lower for diameters 〈12mm compared to 〉/=12mm (p〈0.05). The rate of true positives for solid and part-solid nodules was similar. CONCLUSIONS: Nodule CAD on chest MDCT is robust over a wide range of exposure settings. Noise reduction by IR is not detrimental for CAD, and may be used to improve image quality in the setting of low-dose MDCT for lung cancer screening.
    Type of Publication: Journal article published
    PubMed ID: 25740701
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  • 5
    Keywords: Germany ; LUNG ; imaging ; SYSTEM ; SYSTEMS ; VOLUME ; SAMPLE ; COMPONENTS ; ACCURACY ; MR ; magnetic resonance ; MAGNETIC-RESONANCE ; magnetic resonance imaging ; DIFFERENCE ; AGE ; COMPONENT ; PARAMETERS ; COMPUTED-TOMOGRAPHY ; BODY ; MR imaging ; dynamic magnetic resonance imaging ; BODIES ; CAPACITY ; OBSTRUCTION ; PULMONARY-FUNCTION TESTS ; development ; DIAPHRAGM ; HEALTHY-SUBJECTS ; CYSTIC-FIBROSIS ; SPIROMETRY ; INTERVAL ; analysis ; function ; LUNG-VOLUME ; female ; Male ; AGREEMENT ; RESONANCE ; body posture ; lung function tests ; magnetic resonance-compatible-spirometry ; nonsmokers ; pulmonary mechanics
    Abstract: The aim of this study was to assess the feasibility and accuracy of a novel magnetic resonance-compatible (MRc)-spirometer. The influence of body posture, magnetic resonance (MR)-setting and image acquisition on lung function was evaluated. Dynamic MR imaging (dMRI) was compared with simultaneously measured lung function. The development of the MRc-spirometer was based on a commercial spirometer and evaluated by flow-generator measurements and forced expiratory manoeuvres in 34 healthy nonsmokers (17 females and 17 males, mean age 32.9 yrs). Mean differences between forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were calculated and a sample paired t-test and Bland-Altman plots were generated. A total of I I subjects underwent different subsequent MRc-spirometric measurements to assess the influence of the components of the MR system on lung function. The mean (95% confidence interval) difference of FEV1 and FVC between the two systems was 0.004 (-0.04-0.04) L and 0.018 (-0.05-0.09) L, respectively. In the subgroup analysis, an influence of the MR-system on FEV1 was found. FEV1 correlated well with the dMRI measurement of the apico-diaphragmatic distance-change after the first second of forced expiration (r=0.72). In conclusion, magnetic resonance-compatible-spirometry is feasible, reliable and safe. The magnetic resonance-setting only has a small influence on simultaneously measured forced expiratory volume in one second. Dynamic magnetic resonance imaging measurements correlate well with simultaneously acquired lung function parameters
    Type of Publication: Journal article published
    PubMed ID: 17715166
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  • 6
    Keywords: LUNG ; PERFUSION ; imaging ; SYSTEM ; SYSTEMS ; VENTILATION ; NUCLEAR-MEDICINE ; TIME ; AIR ; MRI ; SIGNAL ; MAGNETIC-RESONANCE ; magnetic resonance imaging ; DIFFERENCE ; NUMBER ; AGE ; WOMEN ; MEN ; DELIVERY ; motion correction ; nuclear medicine ; OXYGEN ; PULMONARY BLOOD-FLOW ; FEASIBILITY ; radiology ; methods ; NUCLEAR ; technique ; USA ; THICKNESS ; DIFFUSING-CAPACITY ; MEDICINE ; VALUES ; SECONDS ; RESPIRATORY SYNCHRONIZATION
    Abstract: Objective: The clinical feasibility of oxygen-enhanced magnetic resonance imaging (MRI) of the lung may benefit from the use of a simple gas delivery method. In this study, the oxygen-induced T1 change of the lung obtained using a closed O-2 delivery system was compared with that obtained by a conventional nontight face mask. Material and Methods: Twenty-three healthy subjects (15 men, 8 women, mean age = 25 years, age range = 20-35 years) underwent oxygen-enhanced MRI of the lung using a closed 02 delivery system composed by a tightly fitting face mask and a 60-L reservoir bag (equipment type A: n = 13, 9 men, 4 women, mean age = 24.4 years, age range = 20-32 years), or a clinically available nontight face mask (equipment type B: n = 10; 6 men, 4 women, mean age = 25.8 years, age range = 20-35 years). The effect of 100%-oxygen inhalation was assessed using a Snapshot FLASH T1-mapping technique (repetition time/echo time 1.5-1.6/0.56 milliseconds; matrix 128 X 90; acquisition time 3.3-3.7 seconds; slice thickness 15-20 mm; number of images = 40). By nonlinear curve fitting, the mean T1 values of the left and right lung at room air and 100%-oxygen ventilation were calculated (T1(room air, right); T1(oxygen, right); T1(room air, left); T1(oxygen, left)). The average T1 differences (Delta T1 = T1(room air) - T1(oxygen)) of the 2 volunteer groups were compared (Wilcoxon signed rank test, Mann-Whimey U test). Results: The mean T1 values obtained using the 2 respiratory equipments at room air or oxygen ventilation were not significantly different (A vs. B at room air ventilation: P = 0.85 for the right lung, P = 0.27 for the left lung; A vs. B at oxygen ventilation: P = 0.55 for the left lung, P = 0.29 for the right lung). With both systems, the mean T1 values decreased significantly after oxygen inhalation (P = 0.03-0.0002). For both lungs, the AT I obtained using the equipment type A was statistically equivalent to that obtained using the equipment type B: Delta T1(A), (right) = 96 +/- 19 milliseconds versus Delta T1(B), (right) = 97 +/- 34 milliseconds (P = 0.82); Delta T1(A), (left) = 74 +/- 47 milliseconds versus Delta T1(B), (left) = 68 +/- 63 milliseconds (P = 0.85). Conclusion: Gas delivery in oxygen-enhanced MRI of the lung can be performed with a clinically available standard face mask, without the need for closed sophisticated equipments
    Type of Publication: Journal article published
    PubMed ID: 18496048
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  • 7
    Keywords: DIAGNOSIS ; SYSTEMS ; TIME ; REPRODUCIBILITY ; COMPUTED-TOMOGRAPHY ; THIN-SECTION CT ; magnetic resonance imaging (MRI) ; CHILDREN ; ADULTS ; cystic fibrosis ; Lung disease ; Scoring system
    Abstract: Magnetic resonance imaging (MRI) gains increasing importance in the assessment of cystic fibrosis (CF) lung disease. The aim of this study was to develop a morpho-functional MR-scoring-system and to evaluate its intra- and inter-observer reproducibility and clinical practicability to monitor CF lung disease over a broad severity range from infancy to adulthood. 35 CF patients with broad age range (mean 15.3years; range 0.5-42) were examined by morphological and functional MRI. Lobe based analysis was performed for parameters bronchiectasis/bronchial-wall-thickening, mucus plugging, abscesses/sacculations, consolidations, special findings and perfusion defects. The maximum global score was 72. Two experienced radiologists scored the images at two time points (interval 10weeks). Upper and lower limits of agreement, concordance correlation coefficients (CCC), total deviation index and coverage probability were calculated for global, morphology, function, component and lobar scores. Global scores ranged from 6 to 47. Intra- and inter-reader agreement for global scores were good (CCC: 0.98 (R1), 0.94 (R2), 0.97 (R1/R2)) and were comparable between high and low scores. Our results indicate that the proposed morpho-functional MR-scoring-system is reproducible and applicable for semi-quantitative evaluation of a large spectrum of CF lung disease severity. This scoring-system can be applied for the routine assessment of CF lung disease and maybe as endpoint for clinical trials.
    Type of Publication: Journal article published
    PubMed ID: 21429685
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  • 8
    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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  • 9
    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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  • 10
    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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