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  • CANCER  (6)
  • DIAGNOSIS  (6)
  • RESOLUTION  (6)
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  • 1
    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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  • 2
    Keywords: CANCER ; COMPUTED-TOMOGRAPHY ; HELICAL CT ; MANAGEMENT ; GUIDELINES ; IMAGE QUALITY ; CHEST CT ; STATEMENT ; SCREENING TRIAL ; LOW-DOSE CT
    Abstract: OBJECTIVES: To evaluate the influence of exposure parameters and raw-data based iterative reconstruction (IR) on the measurement variability of computer-aided nodule volumetry on chest multidetector computed tomography (MDCT). MATERIALS AND METHODS: N=7 porcine lung explants were inflated in a dedicated ex vivo phantom and prepared with n=162 artificial nodules. MDCT was performed eight consecutive times (combinations of 120 and 80 kV with 120, 60, 30 and 12 mAs), and reconstructed with filtered back projection (FBP) and IR. Nodule volume and diameter were measured semi-automatically with dedicated software. The absolute percentage measurement error (APE) was computed in relation to the 120 kV 120 mAs acquisition. Noise was recorded for each nodule in every dataset. RESULTS: Mean nodule volume and diameter were 0.32 +/- 0.15 ml and 12.0 +/- 2.6mm, respectively. Although IR reduced noise by 24.9% on average compared to FBP (p〈0.007), APE with IR was equal to or slightly higher than with FBP. Mean APE for volume increased significantly below a volume computed tomography dose index (CTDI) of 1.0 mGy: for 120 kV 12 mAs APE was 3.8 +/- 6.2% (FBP) vs. 4.0 +/- 5.2% (IR) (p〈0.007); for 80 kV 12 mAs APE was 8.0 +/- 13.0% vs. 9.3 +/- 15.8% (n.s.), respectively. Correlating APE with image noise revealed that at identical noise APE was higher with IR than with FBP (p〈0.05). CONCLUSIONS: Computer-aided volumetry is robust in a wide range of exposure settings, and reproducibility is reduced at a CTDI below 1.0 mGy only, but the error rate remains clinically irrelevant. Noise reduction by IR is not detrimental for measurement error in the setting of semi-automatic nodule volumetry on chest MDCT.
    Type of Publication: Journal article published
    PubMed ID: 23727376
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  • 3
    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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  • 4
    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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  • 5
    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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  • 6
    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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  • 7
    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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  • 8
  • 9
    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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  • 10
    Keywords: Germany ; LUNG ; chest ; CT ; FOLLOW-UP ; imaging ; INFORMATION ; SYSTEM ; TOOL ; DEATH ; POPULATION ; computed tomography ; RESOLUTION ; PATIENT ; IMPACT ; CONTRAST ; MRI ; MAGNETIC-RESONANCE ; magnetic resonance imaging ; COMPUTED-TOMOGRAPHY ; CHILDREN ; LUNG PERFUSION ; ADULTS ; PHASE ; cystic fibrosis
    Abstract: Cystic fibrosis (CF) is the most frequent inherited disorder leading to premature death in the Caucasian population. As life expectancy is limited by pulmonary complications, repeated imaging [chest X-ray, multislice high-resolution computed tomography (MS-HRCT)] is required in the follow-up. Magnetic resonance imaging (MRI) of the lung parenchyma is a promising new diagnostic tool. Its value for imaging lung changes caused by CF compared with CT is demonstrated. MRI performs well when compared with CT, which serves as the gold standard. Its lack in spatial resolution is obvious, but advantages in contrast and functional assessment compensate for this limitation. Thus, MRI is a reasonable alternative for imaging the CF lung and should be introduced as a radiation-free modality for follow-up studies in CF patients. For further evaluation of the impact of MRI, systematic studies comparing MRI and conventional imaging modalities are necessary. Furthermore, the value of the additional functional MRI (fMRI) information has to be studied, and a scoring system for the morphological and functional aspect of MRI has to be established
    Type of Publication: Journal article published
    PubMed ID: 16941092
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