The Experts below are selected from a list of 30 Experts worldwide ranked by ideXlab platform
Werner G Daniel - One of the best experts on this subject based on the ideXlab platform.
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comparison of contrast enhanced breath hold and free breathing Respiratory Gated Imaging in three dimensional magnetic resonance coronary angiography
American Journal of Cardiology, 2002Co-Authors: Matthias Regenfus, Dieter Ropers, Stephan Achenbach, Christian Schlundt, Winfried Kessler, Gerhard Laub, Werner Moshage, Werner G DanielAbstract:Suppression of Respiratory motion is one of the major challenges of magnetic resonance (MR) coronary angiography. Two approaches to compensate for Respiratory motion have often been proposed: breath-hold (BH) and free-breathing Respiratory-Gated (FBRG) Imaging. So far, however, these approaches have never been directly compared. MR coronary angiography was performed in 32 patients with suspected coronary artery disease. MR data were acquired using contrast-enhanced BH and FBRG 3-dimensional MR coronary angiographic techniques. MR images were compared with regard to image quality using quantitative parameters and with regard to accuracy for stenosis detection in the proximal and mid-coronary segments in comparison to x-ray angiography. With regard to image quality, BH was superior to FBRG. Signal-to-noise ratio was 29.1 ± 10.7 for BH versus 18.8 ± 9.7 for FBRG (p <0.05) and contrast-to-noise was 18.0 ± 7.4 for BH versus 11.3 ± 7.9 for FBRG (p ≤0.05). One hundered seventy-one of 224 coronary artery segments (76%) were evaluable in BH compared with 155 of 224 in FBRG (69%). In the evaluable segments, BH demonstrated a sensitivity of 87% (26 of 30 stenoses detected) and specificity of 92% (129 of 141 nonstenotic segments correctly identified), whereas FBRG showed a sensitivity of 60% (15 of 25) and specificity of 89% (115 of 130). Overall accuracy was 91% (155 of 171) for BH and 84% (130 of 155) for FBRG. Sensitivity was significantly higher for BH (p = 0.0320), whereas specificity and overall accuracy were not significantly different. Thus, contrast-enhanced BH MR coronary angiography compares favorably to FBRG Imaging with regard to image quality and detection of coronary stenoses.
C Metreweli - One of the best experts on this subject based on the ideXlab platform.
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magnetic resonance coronary angiography with 3d truefisp breath hold versus Respiratory Gated Imaging
British Journal of Radiology, 2005Co-Authors: Wynnie W M Lam, A K Y Chan, J E Sanderson, C MetreweliAbstract:To compare the diagnostic accuracy of coronary magnetic resonance angiography with three-dimensional (3D) trueFISP breath-hold and Respiratory Gated techniques for the detection of significant coronary artery stenosis. 15 patients who recently underwent elective coronary angiogram were studied and a total of 60 arteries and 48 arteries were assessed by breath-hold and Respiratory Gated 3D trueFISP techniques, respectively. The image quality, length of artery visualized and the presence or absence of significant coronary artery stenosis were recorded. 83.3% and 81.7% of the arteries obtained with the Respiratory Gated and the breath-hold techniques, respectively, had an image quality suitable for further analysis. There was no significant difference in the length of artery visualized. Sensitivity and specificity of 80%, 100% and 75% and 100%, respectively, were obtained with the breath-hold and Respiratory Gated techniques in detecting significant stenosis in the coronary arteries. Both techniques have moderate sensitivity and high specificity in detection of significant stenosis in the visualized segments of the major coronary arteries. However, they cannot replace conventional coronary angiogram for diagnosing coronary artery disease at present. Further studies are required to evaluate whether breath-hold approach is more efficient, therefore should be performed first and Respiratory Gated approach reserved for those who cannot breath-hold.
Matthias Regenfus - One of the best experts on this subject based on the ideXlab platform.
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comparison of contrast enhanced breath hold and free breathing Respiratory Gated Imaging in three dimensional magnetic resonance coronary angiography
American Journal of Cardiology, 2002Co-Authors: Matthias Regenfus, Dieter Ropers, Stephan Achenbach, Christian Schlundt, Winfried Kessler, Gerhard Laub, Werner Moshage, Werner G DanielAbstract:Suppression of Respiratory motion is one of the major challenges of magnetic resonance (MR) coronary angiography. Two approaches to compensate for Respiratory motion have often been proposed: breath-hold (BH) and free-breathing Respiratory-Gated (FBRG) Imaging. So far, however, these approaches have never been directly compared. MR coronary angiography was performed in 32 patients with suspected coronary artery disease. MR data were acquired using contrast-enhanced BH and FBRG 3-dimensional MR coronary angiographic techniques. MR images were compared with regard to image quality using quantitative parameters and with regard to accuracy for stenosis detection in the proximal and mid-coronary segments in comparison to x-ray angiography. With regard to image quality, BH was superior to FBRG. Signal-to-noise ratio was 29.1 ± 10.7 for BH versus 18.8 ± 9.7 for FBRG (p <0.05) and contrast-to-noise was 18.0 ± 7.4 for BH versus 11.3 ± 7.9 for FBRG (p ≤0.05). One hundered seventy-one of 224 coronary artery segments (76%) were evaluable in BH compared with 155 of 224 in FBRG (69%). In the evaluable segments, BH demonstrated a sensitivity of 87% (26 of 30 stenoses detected) and specificity of 92% (129 of 141 nonstenotic segments correctly identified), whereas FBRG showed a sensitivity of 60% (15 of 25) and specificity of 89% (115 of 130). Overall accuracy was 91% (155 of 171) for BH and 84% (130 of 155) for FBRG. Sensitivity was significantly higher for BH (p = 0.0320), whereas specificity and overall accuracy were not significantly different. Thus, contrast-enhanced BH MR coronary angiography compares favorably to FBRG Imaging with regard to image quality and detection of coronary stenoses.
Wynnie W M Lam - One of the best experts on this subject based on the ideXlab platform.
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magnetic resonance coronary angiography with 3d truefisp breath hold versus Respiratory Gated Imaging
British Journal of Radiology, 2005Co-Authors: Wynnie W M Lam, A K Y Chan, J E Sanderson, C MetreweliAbstract:To compare the diagnostic accuracy of coronary magnetic resonance angiography with three-dimensional (3D) trueFISP breath-hold and Respiratory Gated techniques for the detection of significant coronary artery stenosis. 15 patients who recently underwent elective coronary angiogram were studied and a total of 60 arteries and 48 arteries were assessed by breath-hold and Respiratory Gated 3D trueFISP techniques, respectively. The image quality, length of artery visualized and the presence or absence of significant coronary artery stenosis were recorded. 83.3% and 81.7% of the arteries obtained with the Respiratory Gated and the breath-hold techniques, respectively, had an image quality suitable for further analysis. There was no significant difference in the length of artery visualized. Sensitivity and specificity of 80%, 100% and 75% and 100%, respectively, were obtained with the breath-hold and Respiratory Gated techniques in detecting significant stenosis in the coronary arteries. Both techniques have moderate sensitivity and high specificity in detection of significant stenosis in the visualized segments of the major coronary arteries. However, they cannot replace conventional coronary angiogram for diagnosing coronary artery disease at present. Further studies are required to evaluate whether breath-hold approach is more efficient, therefore should be performed first and Respiratory Gated approach reserved for those who cannot breath-hold.
Daniel Bucklan - One of the best experts on this subject based on the ideXlab platform.
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retrospective quantitative analysis comparing Respiratory Gated to non Respiratory Gated 18f fdg pet ct Imaging in patients undergoing evaluation for primary lung cancer
The Journal of Nuclear Medicine, 2019Co-Authors: Eric S Fair, R S Hellman, Daniel BucklanAbstract:1324 Objectives: In patients undergoing evaluation for primary lung cancer, 2-deoxy-2-(18F) fluoro-D-glucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) is a commonly used Imaging examination for staging and treatment evaluation. Maximum and mean standardized uptake values (SUV) are commonly reported for these patients in practice, and metabolic tumor volume (MTV) and total lesion glycolysis (TLG) may have prognostic and treatment-related implications. Respiratory motion can result in displacement of lesions and degrade images of the lower chest in these patients, potentially reducing sensitivity of lesion detection and affecting the quantitative values that may have an effect on disease staging and treatment. We aim to assess the differences in quantitative values on non-Respiratory Gated versus Respiratory Gated FDG PET/CT Imaging for discrete pulmonary lesions in patients undergoing evaluation for primary lung cancer. Methods: This study retrospectively reviewed 35 patients (13 males, 22 females, median age 69) evaluated for primary lung cancer with both non-Respiratory Gated and Respiratory Gated FDG PET/CT Imaging obtained, including 36 separate FDG PET/CT exams and 49 discrete pulmonary lesions. Standard non-Respiratory Gated whole body FDG PET/CT was obtained at multiple bed positions (2 min each) except for sequentially obtained Respiratory Gated PET Imaging at two bed positions (4 min each), encompassing the lower lung fields. An abdominal pressure sensor was used for Respiratory cycle gating from peak inspiration to peak inspiration with data gathered from mid-expiration to mid-inspiration. The mean SUV (SUVmean) metabolic tumor volume (MTV41%), and total lesion glycolysis (TLG41%) were segmented using the software default adaptive threshold of 41% from the maximum in the volume of interest. SUVmax, SUVmean, MTV41%, and TLG41% were measured for each discrete pulmonary lesion on both non-Respiratory Gated and Respiratory Gated Imaging utilizing automated software to calculate values within the volume of interest. Results: Data analysis demonstrates an increase in SUVmax in 81.6% of lesions, an increase in SUVmean in 87.7% of lesions, a decrease in MTV41% in 87.7% of lesions, and a decrease in TLG41% in 83.7% of lesions on Respiratory Gated FDG PET/CT Imaging when compared to non-Respiratory Gated Imaging. Utilizing a paired samples T-test, there was a significant difference between non-Respiratory Gated and Respiratory Gated Imaging, respectively, for SUVmax (mean=8.5, SD=6.7 and mean=9.2, SD=6.8, p= Conclusions: Overall, Respiratory Gated FDG PET/CT Imaging demonstrates a significant increase in SUVmax and SUVmean and a significant decrease in MTV and TLG when compared to non-Respiratory Gated PET/CT Imaging in patients undergoing evaluation for primary lung cancer. The decrease in TLG with Respiratory Gated PET/CT Imaging was an unexpected consequence. Further data analysis can evaluate the effect of lesion size, lesion location, and patient weight on these values.