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Nader Sourour - One of the best experts on this subject based on the ideXlab platform.
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Reliability and Accuracy of Time Resolved Contrast Enhanced Magnetic Resonance Angiography in Hypervascular Spinal Metastases prior Embolization
European Radiology, 2021Co-Authors: Kevin Premat, Eimad Shotar, Robert Burns, Natalia Shor, Gauthier Eloy, Evelyne Cormier, Mehdi Drir, Laetitia Morardet, Stéphanie Lenck, Nader SourourAbstract:Objectives Preoperative embolization of hypervascular spinal metastases (HSM) is efficient to reduce perioperative bleeding. However, intra-arterial digital subtraction angiography (IA-DSA) must confirm the hypervascular nature and rule out spinal cord arterial feeders. This study aimed to evaluate the reliability and accuracy of time-resolved contrast-enhanced magnetic resonance angiography (TR-CE-MRA) in assessing HSM prior to embolization. Methods All consecutive patients referred for preoperative embolization of an HSM were prospectively included. TR-CE-MRA sequences and selective IA-DSA were performed prior to embolization. Two readers independently reviewed imaging data to grade tumor vascularity (using a 3-grade and a dichotomized “yes vs no” scale) and identify the arterial supply of the spinal cord. Interobserver and Intermodality agreements were estimated using kappa statistics. Results Thirty patients included between 2016 and 2019 were assessed for 55 levels. Interobserver agreement was moderate (κ = 0.52; 95% CI [0.09–0.81]) for TR-CE-MRA. Intermodality agreement between TR-CE-MRA and IA-DSA was good (κ = 0.74; 95% CI [0.37–1.00]). TR-CE-MRA had a sensitivity of 97.9%, a specificity of 71.4%, a positive predictive value of 95.9%, a negative predictive value of 83.3%, and an overall accuracy of 94.6%, for differentiating hypervascular from non-hypervascular SM. The arterial supply of the spine was assessable in 2/30 (6.7%) cases with no interobserver agreement (κ < 0). Conclusions TR-CE-MRA can reliably differentiate hypervascular from non-hypervascular SM and thereby avoid futile IA-DSAs. However, TR-CE-MRA was not able to evaluate the vascular supply of the spinal cord at the target levels, thus limiting its scope as a pretherapeutic assessment tool.
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Reliability and accuracy of time-resolved contrast-enhanced magnetic resonance angiography in hypervascular spinal metastases prior embolization
European Radiology, 2021Co-Authors: Kevin Premat, Eimad Shotar, Robert Burns, Natalia Shor, Gauthier Eloy, Evelyne Cormier, Mehdi Drir, Laetitia Morardet, Stéphanie Lenck, Nader SourourAbstract:Objectives Preoperative embolization of hypervascular spinal metastases (HSM) is efficient to reduce perioperative bleeding. However, intra-arterial digital subtraction angiography (IA-DSA) must confirm the hypervascular nature and rule out spinal cord arterial feeders. This study aimed to evaluate the reliability and accuracy of time-resolved contrast-enhanced magnetic resonance angiography (TR-CE-MRA) in assessing HSM prior to embolization. Methods All consecutive patients referred for preoperative embolization of an HSM were prospectively included. TR-CE-MRA sequences and selective IA-DSA were performed prior to embolization. Two readers independently reviewed imaging data to grade tumor vascularity (using a 3-grade and a dichotomized “yes vs no” scale) and identify the arterial supply of the spinal cord. Interobserver and Intermodality agreements were estimated using kappa statistics. Results Thirty patients included between 2016 and 2019 were assessed for 55 levels. Interobserver agreement was moderate (κ = 0.52; 95% CI [0.09–0.81]) for TR-CE-MRA. Intermodality agreement between TR-CE-MRA and IA-DSA was good (κ = 0.74; 95% CI [0.37–1.00]). TR-CE-MRA had a sensitivity of 97.9%, a specificity of 71.4%, a positive predictive value of 95.9%, a negative predictive value of 83.3%, and an overall accuracy of 94.6%, for differentiating hypervascular from non-hypervascular SM. The arterial supply of the spine was assessable in 2/30 (6.7%) cases with no interobserver agreement (κ < 0). Conclusions TR-CE-MRA can reliably differentiate hypervascular from non-hypervascular SM and thereby avoid futile IA-DSAs. However, TR-CE-MRA was not able to evaluate the vascular supply of the spinal cord at the target levels, thus limiting its scope as a pretherapeutic assessment tool. Key Points • TR-CE-MRA aids in distinguishing hypervascular from non-hypervascular spinal metastases. • TR-CE-MRA could avoid one-quarter of patients referred for HSM embolization to undergo futile conventional angiography. • TR-CE-MRA’s spatial resolution is insufficient to replace IA-DSA in the pretherapeutic assessment of the spinal cord vascular anatomy.
Kevin Premat - One of the best experts on this subject based on the ideXlab platform.
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Reliability and Accuracy of Time Resolved Contrast Enhanced Magnetic Resonance Angiography in Hypervascular Spinal Metastases prior Embolization
European Radiology, 2021Co-Authors: Kevin Premat, Eimad Shotar, Robert Burns, Natalia Shor, Gauthier Eloy, Evelyne Cormier, Mehdi Drir, Laetitia Morardet, Stéphanie Lenck, Nader SourourAbstract:Objectives Preoperative embolization of hypervascular spinal metastases (HSM) is efficient to reduce perioperative bleeding. However, intra-arterial digital subtraction angiography (IA-DSA) must confirm the hypervascular nature and rule out spinal cord arterial feeders. This study aimed to evaluate the reliability and accuracy of time-resolved contrast-enhanced magnetic resonance angiography (TR-CE-MRA) in assessing HSM prior to embolization. Methods All consecutive patients referred for preoperative embolization of an HSM were prospectively included. TR-CE-MRA sequences and selective IA-DSA were performed prior to embolization. Two readers independently reviewed imaging data to grade tumor vascularity (using a 3-grade and a dichotomized “yes vs no” scale) and identify the arterial supply of the spinal cord. Interobserver and Intermodality agreements were estimated using kappa statistics. Results Thirty patients included between 2016 and 2019 were assessed for 55 levels. Interobserver agreement was moderate (κ = 0.52; 95% CI [0.09–0.81]) for TR-CE-MRA. Intermodality agreement between TR-CE-MRA and IA-DSA was good (κ = 0.74; 95% CI [0.37–1.00]). TR-CE-MRA had a sensitivity of 97.9%, a specificity of 71.4%, a positive predictive value of 95.9%, a negative predictive value of 83.3%, and an overall accuracy of 94.6%, for differentiating hypervascular from non-hypervascular SM. The arterial supply of the spine was assessable in 2/30 (6.7%) cases with no interobserver agreement (κ < 0). Conclusions TR-CE-MRA can reliably differentiate hypervascular from non-hypervascular SM and thereby avoid futile IA-DSAs. However, TR-CE-MRA was not able to evaluate the vascular supply of the spinal cord at the target levels, thus limiting its scope as a pretherapeutic assessment tool.
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Reliability and accuracy of time-resolved contrast-enhanced magnetic resonance angiography in hypervascular spinal metastases prior embolization
European Radiology, 2021Co-Authors: Kevin Premat, Eimad Shotar, Robert Burns, Natalia Shor, Gauthier Eloy, Evelyne Cormier, Mehdi Drir, Laetitia Morardet, Stéphanie Lenck, Nader SourourAbstract:Objectives Preoperative embolization of hypervascular spinal metastases (HSM) is efficient to reduce perioperative bleeding. However, intra-arterial digital subtraction angiography (IA-DSA) must confirm the hypervascular nature and rule out spinal cord arterial feeders. This study aimed to evaluate the reliability and accuracy of time-resolved contrast-enhanced magnetic resonance angiography (TR-CE-MRA) in assessing HSM prior to embolization. Methods All consecutive patients referred for preoperative embolization of an HSM were prospectively included. TR-CE-MRA sequences and selective IA-DSA were performed prior to embolization. Two readers independently reviewed imaging data to grade tumor vascularity (using a 3-grade and a dichotomized “yes vs no” scale) and identify the arterial supply of the spinal cord. Interobserver and Intermodality agreements were estimated using kappa statistics. Results Thirty patients included between 2016 and 2019 were assessed for 55 levels. Interobserver agreement was moderate (κ = 0.52; 95% CI [0.09–0.81]) for TR-CE-MRA. Intermodality agreement between TR-CE-MRA and IA-DSA was good (κ = 0.74; 95% CI [0.37–1.00]). TR-CE-MRA had a sensitivity of 97.9%, a specificity of 71.4%, a positive predictive value of 95.9%, a negative predictive value of 83.3%, and an overall accuracy of 94.6%, for differentiating hypervascular from non-hypervascular SM. The arterial supply of the spine was assessable in 2/30 (6.7%) cases with no interobserver agreement (κ < 0). Conclusions TR-CE-MRA can reliably differentiate hypervascular from non-hypervascular SM and thereby avoid futile IA-DSAs. However, TR-CE-MRA was not able to evaluate the vascular supply of the spinal cord at the target levels, thus limiting its scope as a pretherapeutic assessment tool. Key Points • TR-CE-MRA aids in distinguishing hypervascular from non-hypervascular spinal metastases. • TR-CE-MRA could avoid one-quarter of patients referred for HSM embolization to undergo futile conventional angiography. • TR-CE-MRA’s spatial resolution is insufficient to replace IA-DSA in the pretherapeutic assessment of the spinal cord vascular anatomy.
Katsuaki Tanaka - One of the best experts on this subject based on the ideXlab platform.
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focal liver tumors characterization with 3d perflubutane microbubble contrast agent enhanced us versus 3d contrast enhanced multidetector ct
Radiology, 2009Co-Authors: Wen Luo, Kazushi Numata, Manabu Morimoto, Masaaki Kondo, Satoshi Morita, Shigeo Takebayashi, Masahiro Okada, Katsuaki TanakaAbstract:Purpose: To investigate the potential application of contrast material–enhanced three-dimensional (3D) ultrasonography (US), as compared with contrast-enhanced 3D computed tomography (CT), for characterization of focal liver tumors. Materials and Methods: Institutional review board approval and informed patient consent were obtained. One hundred thirty-nine patients with focal liver tumors—77 hepatocellular carcinomas (HCCs), 33 metastases, 23 hemangiomas, and six focal nodular hyperplasias (FNHs)—who were examined at 3D US enhanced with a perflubutane microbubble contrast agent and at 3D contrast-enhanced multidetector CT were retrospectively identified. Two readers blindly reviewed the multiplanar images and angiograms reconstructed with both modalities and classified the depicted lesions according to diagnostic criteria based on their experience and published findings. Sensitivity, specificity, positive predictive value (PPV), area under the receiver operating characteristic curve (Az), Intermodality a...
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Focal Liver Tumors: Characterization with 3D Perflubutane Microbubble Contrast Agent–enhanced US versus 3D Contrast-enhanced Multidetector CT
Radiology, 2009Co-Authors: Wen Luo, Kazushi Numata, Manabu Morimoto, Masaaki Kondo, Satoshi Morita, Shigeo Takebayashi, Masahiro Okada, Katsuaki TanakaAbstract:Purpose: To investigate the potential application of contrast material–enhanced three-dimensional (3D) ultrasonography (US), as compared with contrast-enhanced 3D computed tomography (CT), for characterization of focal liver tumors. Materials and Methods: Institutional review board approval and informed patient consent were obtained. One hundred thirty-nine patients with focal liver tumors—77 hepatocellular carcinomas (HCCs), 33 metastases, 23 hemangiomas, and six focal nodular hyperplasias (FNHs)—who were examined at 3D US enhanced with a perflubutane microbubble contrast agent and at 3D contrast-enhanced multidetector CT were retrospectively identified. Two readers blindly reviewed the multiplanar images and angiograms reconstructed with both modalities and classified the depicted lesions according to diagnostic criteria based on their experience and published findings. Sensitivity, specificity, positive predictive value (PPV), area under the receiver operating characteristic curve (Az), Intermodality a...
L. Pierot - One of the best experts on this subject based on the ideXlab platform.
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Contrast-Enhanced and Time-of-Flight MRA at 3T Compared with DSA for the Follow-Up of Intracranial Aneurysms Treated with the WEB Device
American Journal of Neuroradiology, 2016Co-Authors: C. Timsit, C. Portefaix, S. Soize, A. Benaissa, J.-y. Gauvrit, L. PierotAbstract:BACKGROUND AND PURPOSE: Imaging follow-up at 3T of intracranial aneurysms treated with the WEB Device has not been evaluated yet. Our aim was to assess the diagnostic accuracy of 3D-time-of-flight MRA and contrast-enhanced MRA at 3T against DSA, as the criterion standard, for the follow-up of aneurysms treated with the Woven EndoBridge (WEB) system. MATERIALS AND METHODS: From June 2011 to December 2014, patients treated with the WEB in our institution, then followed for ≥6 months after treatment by MRA at 3T (3D-TOF-MRA and contrast-enhanced MRA) and DSA within 48 hours were included. Aneurysm occlusion was assessed with a simplified 2-grade scale (adequate occlusion [total occlusion + neck remnant] versus aneurysm remnant). Interobserver and Intermodality agreement was evaluated by calculating the linear weighted κ. MRA test characteristics and predictive values were calculated from a 2 × 2 contingency table, by using DSA data as the standard of reference. RESULTS: Twenty-six patients with 26 WEB-treated aneurysms were included. The interobserver reproducibility was good with DSA (κ = 0.71) and contrast-enhanced-MRA (κ = 0.65) compared with moderate with 3D-TOF-MRA (κ = 0.47). Intermodality agreement with DSA was fair with both contrast-enhanced MRA (κ = 0.36) and 3D-TOF-MRA (κ = 0.36) for the evaluation of total occlusion. For aneurysm remnant detection, the prevalence was low (15%), on the basis of DSA, and both MRA techniques showed low sensitivity (25%), high specificity (100%), very good positive predictive value (100%), and very good negative predictive value (88%). CONCLUSIONS: Despite acceptable interobserver reproducibility and predictive values, the low sensitivity of contrast-enhanced MRA and 3D-TOF-MRA for aneurysm remnant detection suggests that MRA is a useful screening procedure for WEB-treated aneurysms, but similar to stents and flow diverters, DSA remains the criterion standard for follow-up.
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Brain arteriovenous malformation diagnosis: value of time-resolved contrast-enhanced MR angiography at 3.0T compared to DSA
Neuroradiology, 2012Co-Authors: A. Machet, C. Portefaix, K. Kadziolka, G. Robin, O. Lanoix, L. PierotAbstract:Introduction This study was conducted in order to evaluate the value of time-resolved contrast-enhanced magnetic resonance angiography (TR-CE-MRA) with a 3.0-T magnetic field compared to digital subtraction angiography (DSA) as the reference standard for the diagnosis of brain arteriovenous malformation (bAVM). Methods Nineteen patients with 19 angiographically confirmed untreated bAVM were investigated with both DSA and TR-CE-MRA for the initial diagnosis. Examinations were compared by two independent readers. Interobserver agreement and Intermodality agreement with respect to nidus size, arterial feeders, and venous drainage were determined using the K statistic test. Also, the quality of the TR-CE-MRA images was evaluated. Results Seventeen of the 19 bAVM (89.5%) detected with DSA were diagnosed with TR-CE-MRA. Interobserver agreement for TR-CE-MRA was good for nidus size, venous drainage, and arterial feeders ( K = 0.75, 95% CI 0.50–1.00; K = 0.77, 95% CI 0.54–1.00; and K = 0.80, 95% CI 0.59–1.00 respectively). Intermodality agreement was good for nidus size and venous drainage ( K = 0.75, 95% CI 0.49–1.00 and K = 0.77, 95% CI 0.54–1.00, respectively) and moderate for arterial feeders ( K = 0.44, 95% CI 0.17–0.70). Conclusion TR-CE-MRA at 3.0 T has a good sensitivity for bAVM detection and good agreement with DSA for determining nidus size and the type of venous drainage, suggesting that TR-CE-MRA is potentially a reliable tool for the diagnosis and assessment of bAVMs. However, it still suffers from low spatial resolution and vessel superposition, making differentiation of the arterial feeders of the nidus difficult at times.
Robert Burns - One of the best experts on this subject based on the ideXlab platform.
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Reliability and Accuracy of Time Resolved Contrast Enhanced Magnetic Resonance Angiography in Hypervascular Spinal Metastases prior Embolization
European Radiology, 2021Co-Authors: Kevin Premat, Eimad Shotar, Robert Burns, Natalia Shor, Gauthier Eloy, Evelyne Cormier, Mehdi Drir, Laetitia Morardet, Stéphanie Lenck, Nader SourourAbstract:Objectives Preoperative embolization of hypervascular spinal metastases (HSM) is efficient to reduce perioperative bleeding. However, intra-arterial digital subtraction angiography (IA-DSA) must confirm the hypervascular nature and rule out spinal cord arterial feeders. This study aimed to evaluate the reliability and accuracy of time-resolved contrast-enhanced magnetic resonance angiography (TR-CE-MRA) in assessing HSM prior to embolization. Methods All consecutive patients referred for preoperative embolization of an HSM were prospectively included. TR-CE-MRA sequences and selective IA-DSA were performed prior to embolization. Two readers independently reviewed imaging data to grade tumor vascularity (using a 3-grade and a dichotomized “yes vs no” scale) and identify the arterial supply of the spinal cord. Interobserver and Intermodality agreements were estimated using kappa statistics. Results Thirty patients included between 2016 and 2019 were assessed for 55 levels. Interobserver agreement was moderate (κ = 0.52; 95% CI [0.09–0.81]) for TR-CE-MRA. Intermodality agreement between TR-CE-MRA and IA-DSA was good (κ = 0.74; 95% CI [0.37–1.00]). TR-CE-MRA had a sensitivity of 97.9%, a specificity of 71.4%, a positive predictive value of 95.9%, a negative predictive value of 83.3%, and an overall accuracy of 94.6%, for differentiating hypervascular from non-hypervascular SM. The arterial supply of the spine was assessable in 2/30 (6.7%) cases with no interobserver agreement (κ < 0). Conclusions TR-CE-MRA can reliably differentiate hypervascular from non-hypervascular SM and thereby avoid futile IA-DSAs. However, TR-CE-MRA was not able to evaluate the vascular supply of the spinal cord at the target levels, thus limiting its scope as a pretherapeutic assessment tool.
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Reliability and accuracy of time-resolved contrast-enhanced magnetic resonance angiography in hypervascular spinal metastases prior embolization
European Radiology, 2021Co-Authors: Kevin Premat, Eimad Shotar, Robert Burns, Natalia Shor, Gauthier Eloy, Evelyne Cormier, Mehdi Drir, Laetitia Morardet, Stéphanie Lenck, Nader SourourAbstract:Objectives Preoperative embolization of hypervascular spinal metastases (HSM) is efficient to reduce perioperative bleeding. However, intra-arterial digital subtraction angiography (IA-DSA) must confirm the hypervascular nature and rule out spinal cord arterial feeders. This study aimed to evaluate the reliability and accuracy of time-resolved contrast-enhanced magnetic resonance angiography (TR-CE-MRA) in assessing HSM prior to embolization. Methods All consecutive patients referred for preoperative embolization of an HSM were prospectively included. TR-CE-MRA sequences and selective IA-DSA were performed prior to embolization. Two readers independently reviewed imaging data to grade tumor vascularity (using a 3-grade and a dichotomized “yes vs no” scale) and identify the arterial supply of the spinal cord. Interobserver and Intermodality agreements were estimated using kappa statistics. Results Thirty patients included between 2016 and 2019 were assessed for 55 levels. Interobserver agreement was moderate (κ = 0.52; 95% CI [0.09–0.81]) for TR-CE-MRA. Intermodality agreement between TR-CE-MRA and IA-DSA was good (κ = 0.74; 95% CI [0.37–1.00]). TR-CE-MRA had a sensitivity of 97.9%, a specificity of 71.4%, a positive predictive value of 95.9%, a negative predictive value of 83.3%, and an overall accuracy of 94.6%, for differentiating hypervascular from non-hypervascular SM. The arterial supply of the spine was assessable in 2/30 (6.7%) cases with no interobserver agreement (κ < 0). Conclusions TR-CE-MRA can reliably differentiate hypervascular from non-hypervascular SM and thereby avoid futile IA-DSAs. However, TR-CE-MRA was not able to evaluate the vascular supply of the spinal cord at the target levels, thus limiting its scope as a pretherapeutic assessment tool. Key Points • TR-CE-MRA aids in distinguishing hypervascular from non-hypervascular spinal metastases. • TR-CE-MRA could avoid one-quarter of patients referred for HSM embolization to undergo futile conventional angiography. • TR-CE-MRA’s spatial resolution is insufficient to replace IA-DSA in the pretherapeutic assessment of the spinal cord vascular anatomy.