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  • PATIENT  (7)
  • 1
    Keywords: measurement ; ANGIOGENESIS ; Germany ; PERFUSION ; CLASSIFICATION ; CT ; imaging ; INFORMATION ; QUANTIFICATION ; liver ; TISSUE ; TUMORS ; computed tomography ; PATIENT ; BLOOD-FLOW ; INDEX ; primary ; INJECTION ; SIGNAL ; LESIONS ; PATTERNS ; DIFFERENCE ; metastases ; US ; tomography ; COMPUTED-TOMOGRAPHY ; LIVER METASTASES ; POWER DOPPLER SONOGRAPHY ; VASCULARIZATION ; contrast-enhanced ultrasound,liver metastases,arterial perfusion,low-MI imaging,SonoVue ; MICROBUBBLE CONTRAST ; SHU 508A
    Abstract: Rationale and Objectives: We investigated whether observing the arterial vascularization of liver metastases by contrast-enhanced ultrasound with low mechanical index (low-MI) imaging offers additional diagnostic information for the characterization of the liver lesions.Methods: Twenty nine patients with untreated liver metastases of different primaries were examined. Measurements were performed using a low frame rate, low-MI pulse inversion technique after injection of 2.4 mL SonoVue. The relative maximum signal intensity of the liver lesions related to the normal liver tissue was quantified. Ultrasound findings were compared with contrast-enhanced, dual-phase computed tomography (CT) using a pattern-based classification scheme.Results: Compared with contrast-enhanced CT, this modality better detects arterial perfusion. Metastases, even those usually considered hypovascularized, often showed homogeneous enhancement (66%) and higher arterial vascularization than normal liver tissue. CT did not show a comparable vascularization pattern (P 〈 0.001) or any similarly early signal intensity (P 〈 0.001).Conclusions: Contrast-enhanced CT may not be able to visualize short-lasting but large differences of the arterial perfusion of liver metastases, as does contrast-enhanced low-MI ultrasound. This offers new methods for their characterization and for monitoring of therapeutic effects
    Type of Publication: Journal article published
    PubMed ID: 15021325
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  • 2
    Keywords: CANCER ; tumor ; carcinoma ; Germany ; LUNG ; PERFUSION ; THERAPY ; CT ; DENSITY ; LUNG-CANCER ; NEW-YORK ; TUMORS ; PATIENT ; CONTRAST ; INJECTION ; treatment ; DIFFERENCE ; REGION ; REGIONS ; LOCALIZATION ; PARAMETERS ; tomography ; CARCINOMAS ; COMPUTED-TOMOGRAPHY ; PET ; lung neoplasms ; PULMONARY ; DYNAMIC CT ; X-ray computed
    Abstract: Advanced bronchial carcinomas by means of perfusion and peak enhancement using dynamic contrast-enhanced multislice CT are characterized. Twenty-four patients with advanced bronchial carcinoma were examined. During breathhold, after injection of a contrast-medium (CM), 25 scans were performed (I scan/s) at a fixed table position. Density-time curves were evaluated from regions of interest of the whole tumor and high- and low-enhancing tumor areas. Perfusion and peak enhancement were calculated using the maximum-slope method of Miles and compared with size, localization (central or peripheral) and histology. Perfusion of large tumors (〉50 cm(3)) averaged over both the whole tumor (P=0.001) and the highest enhancing area (P=0.003) was significantly lower than that of smaller ones. Independent of size, central carcinomas had a significantly (P=0.04) lower perfusion (mean 27.9 ml/min/100 g) than peripheral ones (mean 66.5 ml/min/100 9). In contrast, peak enhancement of central and peripheral carcinomas was not significantly different. Between non-small-cell lung cancers and small-cell lung cancers, no significant differences were observed in both parameters. In seven tumors, density increase after CM administration started earlier than in the aorta, indicating considerable blood supply from pulmonary vessels. Tumor perfusion was dependent on tumor size and localization, but not on histology. Furthermore, perfusion CT disclosed blood supply from both pulmonary and/or bronchial vessels in some tumors
    Type of Publication: Journal article published
    PubMed ID: 15029450
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  • 3
    Keywords: Germany ; LUNG ; CT ; EMPHYSEMA ; HIGH-RESOLUTION CT ; QUANTIFICATION ; VOLUME ; PATIENT ; IMPACT ; REDUCTION ; SIMULATION ; PARAMETERS ; COMPUTED-TOMOGRAPHY ; OBSTRUCTIVE PULMONARY-DISEASE ; THIN-SECTION CT ; HELICAL CT ; RE ; multidetector CT ; LUNG-VOLUME ; low dose ; MULTISLICE CT ; 3-dimensional quantitative volumetric analysis ; ALPHA-1-ANTITRYPSIN DEFICIENCY ; dose simulation ; LUNG DENSITY-MEASUREMENTS ; MACROSCOPIC MORPHOMETRY ; multidetector computed tomography ; VOLUME REDUCTION
    Abstract: Purpose: Quantitative evaluation of the lung parenchyma might be impaired or unreliable by use of reduced-dose CT protocols. Aim of the study was to define the threshold where reduced dose has significant impact on quantitative emphysema parameters. Materials and Methods: Thirty patients with severe centrilobular emphysema underwent multidetector computed tomography (120 kV, 150 mAs). Original CT raw data were simulated using 10 mAs settings (10-100 SlMmAs). Quantitative analysis provided lung volume, emphysema volume, emphysema index, mean lung density, and 4 emphysema volume classes. Simulated low-dose results were compared with original acquisition. Results: Emphysema index showed no clinical relevant variation down to 30 SlMmAs. The large emphysema volume class was significantly different below 50 SlMmAs. The intermediate and small classes showed an overproportional variation below 50 SlMmAs. Conclusions: Dose reduction down to 30 SlMmAs is possible for clinical routine. Settings below 50 SlMmAs significantly alter the indetailed 3-dimensional emphysema quantification
    Type of Publication: Journal article published
    PubMed ID: 16778622
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  • 4
    Keywords: tumor ; COMBINATION ; evaluation ; Germany ; THERAPY ; CT ; FOLLOW-UP ; imaging ; VOLUME ; DISEASE ; NEW-YORK ; validation ; NUCLEAR-MEDICINE ; PATIENT ; MRI ; SEQUENCE ; SEQUENCES ; chemotherapy ; VARIABILITY ; FUNCTION TESTS ; MOTION ; nuclear medicine ; mesothelioma ; PLEURAL MESOTHELIOMA ; dynamic MRI ; radiology ; malignant pleural mesothelioma ; THERAPIES ; IMAGING TECHNIQUES ; WEIGHT ; breathing cycle ; NUCLEAR ; CRITERIA ; technique ; USA ; correlation ; MEDICINE ; comparison ; KAPPA ; VALUES ; INTEROBSERVER ; RECIST ; RECIST CRITERIA ; MPM ; tumour volumetry
    Abstract: To evaluate and compare early therapy response according to RECIST (response evaluation criteria in solid tumours) and modified RECIST criteria using MRI techniques in patients with malignant pleural mesothelioma (MPM) in comparison with CT. Fifty patients with MPM (32 male/18 female) were included in this study. Early therapy response was evaluated after 9 weeks [three of six chemotherapy (CHT)] cycles. Additionally patients were examined before chemotherapy, 4 weeks after early therapy response evaluation and after six cycles to evaluate diagnostic follow-up. RECIST and modified RECIST criteria were applied using CT and MRI (HASTE, VIBE, T2-TSE sequences). In MRI additionally a volumetric approach measuring tumour weight (overall segmented tumour volume) was applied. Additionally vital capacity (VC) was measured for correlation. Image interpretation was performed by three independent readers independently and in consensus. The 'gold standard' was follow-up examination. Twenty-eight patients showed partial response, 12 patients stable disease and 10 patients progressive disease at early therapy response evaluation. In the follow-up these results remained. For MRI, in 46 cases patients were identically classified using RECIST and modified RECIST criteria. Modified RECIST criteria were identically classified as gold standards in all cases, whereas using RECIST criteria in four cases there was a mismatch (partial response vs. stable disease). Modified RECIST kappa values showed better interobserver variability compared with RECIST criteria (kappa=0.9-1.0 vs. 0.7-1.0). For CT, in 44 cases patients were identically classified using RECIST and modified RECIST criteria. Modified RECIST criteria were identically classified as in gold standards in 48 out of 50 patients, whereas using RECIST criteria in 6 cases there was a mismatch (partial response vs. stable disease). Modified RECIST kappa values showed better interobserver variability compared with RECIST criteria (kappa=0.9-1.0 vs. 0.6-1.0). Modified RECIST criteria especially in combination with high-resolution MRI is a very accurate and reproducible technique to correctly evaluate early therapy response in MPM
    Type of Publication: Journal article published
    PubMed ID: 18369634
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  • 5
    Keywords: brain ; RECEPTOR ; CANCER ; EXPRESSION ; BLOOD ; Germany ; LUNG ; MODEL ; imaging ; lung cancer ; LUNG-CANCER ; POPULATION ; GENE ; GENE-EXPRESSION ; TISSUE ; PATIENT ; CONTRAST ; gene expression ; metastases ; PARAMETERS ; SCINTIGRAPHY ; PET ; SOMATOSTATIN ; QUANTITATIVE ASSESSMENT ; RE ; SOMATOSTATIN ANALOG ; GA-68-DOTATOC ; LOSSES ; uptake ; FDG ; viability ; DOTATOC ; EMISSION-TOMOGRAPHY ; F-18-FDG PET ; kinetic modelling ; kinetic parameters ; non-small cell lung tumours ; TC-99M DEPREOTIDE
    Abstract: Purpose: Dynamic PET studies with Ga-68-DOTATOC were performed in patients with non-small cell lung cancer (NSCLC) to assess the somatostatin receptor 2 (SSTR2) expression. Furthermore, dynamic F-18-fluorodeoxyglucose (FDG) studies were performed in the same patients to compare the SSTR2 expression with the tumour viability. Methods: The study population comprised nine patients, examined with both tracers on two different days within 1 week. Standardised uptake values (SUVs) were calculated and a two-tissue compartment model was applied to the data. Furthermore, a non-compartment model based on the fractal dimension (FD) was applied to the data. Results: The DOTATOC uptake was generally lower than the FDG uptake. Moderately enhanced DOTATOC uptake was noted in seven of the nine tumours. All kinetic parameters exceptk (4) were lower for DOTATOC than for FDG. The mean SUV was 2.018 for DOTATOC, in comparison to 5.683 for FDG. In particular,k (3) was highly variable for DOTATOC and showed an overlap with the normal lung tissue. The fractional blood volumeV (B) was relatively low for both tracers, not exceeding 0.3. The highest significant logarithmic correlation was found for the FD of the two tracers (r=0.764,p=0.017). The logarithmic correlation for SUVs was also significant (r=0.646,p=0.060), as was that forV (B) (r=0.629,p=0.069). In contrast, none of the eight metastases which were positive on FDG PET showed any DOTATOC uptake. Conclusion: The results demonstrated moderate Ga-68-DOTATOC uptake in primary NSCLC but did not provide any evidence for SSTR2 expression in metastases. This may be caused by loss of the gene expression in metastases as compared with the primary tumours
    Type of Publication: Journal article published
    PubMed ID: 16570185
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  • 6
    Keywords: Germany ; LUNG ; PERFUSION ; THERAPY ; FOLLOW-UP ; imaging ; VOLUME ; DISEASE ; PATIENT ; MRI ; CYCLE ; magnetic resonance imaging ; MOBILITY ; chemotherapy ; FUNCTION TESTS ; MOTION ; PLEURAL MESOTHELIOMA ; dynamic MRI ; 2D ; breathing cycle ; DIAPHRAGM ; HEALTHY-SUBJECTS ; SPIROMETRY ; volumetry ; LUNG-VOLUME ; therapy monitoring ; 3D volumetry
    Abstract: Purpose: To monitor lung motion in patients with malignant pleural mesothelioma (MPM) before and after chemotherapy (CHT) using 2-dimensional (2D) and 3-dimensional (3D) dynamic MRI (dMRI) in comparison with spirometry. Methods and Materials: Twenty-two patients with MPM were examined before CHT, as well as after 3 and 6 CHT cycles (3 months and 6 months) using 2D dMRI (trueFISP; 3 images/s) and 3D dMRI (FLASH 3D, I slab (52 slices)/s) using parallel imaging in combination with view-sharing technique. Maximum craniocaudal lung dimensions (2D) and lung volumes (3D) were monitored, separated into the tumor-bearing and nontumor-bearing hemithorax. Vital capacity (VC) was measured for comparison using spirometry. Results: Using 2D technique, there was a significant difference between the tumor-bearing and the nontumor-bearing hemithorax before CHT (P 〈 0.01) and after 3 CHT cycles (P 〈 0.05), whereas difference was not significant in the second control. In the tumor-bearing hemithorax, mobility increased significantly from the status before versus after 3 CHT cycles (4.1 +/- 1.1 cm vs. 4.8 +/- 1.4 cm, P 〈 0.05). Using 3D technique, at maximum inspiration, the volume of the tumor-bearing hemithorax was 0.6 +/- 0.4 L and of the nontumor-bearing hemithorax 1.25 +/- 0.4 L before CHT. In the follow-up exams, these volumes changed to 1.05 +/- 0.4 L (P 〈 0.05) and 1.4 +/- 0.5 L, respectively. Using spirometry, there was no significant change in VC (1.9 +/- 0.4 L vs. 2.2 +/- 0.7 L vs. 2.2 +/- 0.9 L). Conclusion: dMRI is capable of monitoring changes in lung, motion and volumetry in patients with MPM not detected by global spirornetry. Thus, dMRI is proposed for use as a further measure of therapy response
    Type of Publication: Journal article published
    PubMed ID: 16625107
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  • 7
    Keywords: CANCER ; radiotherapy ; carcinoma ; Germany ; LUNG ; imaging ; thorax ; RESOLUTION ; PATIENT ; tumour ; MRI ; CYCLE ; SEQUENCE ; SEQUENCES ; LESIONS ; MOBILITY ; MOTION ; QUANTITATIVE-ANALYSIS ; dynamic MRI ; STAGE-I ; TRUEFISP ; GRADIENT-ECHO ; breathing cycle ; DIAPHRAGM ; HEALTHY-SUBJECTS ; lung motion ; parallel imaging ; SENSE ; SMASH ; TEMPORAL RESOLUTION ; volumetry
    Abstract: The purpose of this study was to describe the use of parallel imaging technique (PAT) using dynamic MRI in lung and tumour-mobility during the breathing cycle. 20 patients with stage I non-small cell lung carcinoma were investigated using two dynamic gradient echo sequences with PAT (TrueFISP (fast imaging with steady precession), and fast low angle shot (FLASH). Craniocaudal distance from the apex to the diaphragm of the thorax and tumour mobility during the breathing cycle were measured. Signal-to-noise ratio (SNR) of the tumour was determined. In spite of the different temporal resolutions both trueFISP and FLASH sequence proved to be adequate to continuously measure lung motion and tumour mobility. SNR of the tumour was significantly higher using the trueFISP sequence than FLASH sequence (20.7 +/- 3.6 vs 5.8 +/- 2.3, p 〈 0.01). Mobility of the tumour bearing hemithorax was significantly lower compared with the non-tumour bearing hemithorax (p 〈 0.05). Dynamic MRI using PAT allows for continuous quantitative documentation of tumour mobility and lung motion. Because of the higher SNR, trueFISP sequence provides a better delineation of intrapulmonary lesions with a sufficient temporal resolution
    Type of Publication: Journal article published
    PubMed ID: 16110107
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