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Richard L Robertson - One of the best experts on this subject based on the ideXlab platform.
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comparison of cbf measured with combined velocity selective arterial spin labeling and pulsed arterial spin labeling to blood flow patterns assessed by Conventional Angiography in pediatric moyamoya
American Journal of Neuroradiology, 2019Co-Authors: Divya S Bolar, Darren B Orbach, Borjan Gagoski, Edward R Smith, Elfar Adalsteinsson, P E Grant, Bruce R. Rosen, Richard L RobertsonAbstract:BACKGROUND AND PURPOSE: Imaging CBF is important for managing pediatric moyamoya. Traditional arterial spin-labeling MR imaging detects delayed transit thorough diseased arteries but is inaccurate for measuring perfusion because of these delays. Velocity-selective arterial spin-labeling is insensitive to transit delay and well-suited for imaging Moyamoya perfusion. This study assesses the accuracy of a combined velocity-selective arterial spin-labeling and traditional pulsed arterial spin-labeling CBF approach in pediatric moyamoya, with comparison to blood flow patterns on Conventional Angiography. MATERIALS AND METHODS: Twenty-two neurologically stable pediatric patients with moyamoya and 5 asymptomatic siblings without frank moyamoya were imaged with velocity-selective arterial spin-labeling, pulsed arterial spin-labeling, and DSA (patients). Qualitative comparison was performed, followed by a systematic comparison using ASPECTS-based scoring. Quantitative pulsed arterial spin-labeling CBF and velocity-selective arterial spin-labeling CBF for the middle cerebral artery, anterior cerebral artery, and posterior cerebral artery territories were also compared. RESULTS: Qualitatively, velocity-selective arterial spin-labeling perfusion maps reflect the DSA parenchymal phase, regardless of postinjection timing. Conversely, pulsed arterial spin-labeling maps reflect the DSA appearance at postinjection times closer to the arterial spin-labeling postlabeling delay, regardless of vascular phase. ASPECTS comparison showed excellent agreement (88%, κ = 0.77, P CONCLUSIONS: Velocity-selective arterial spin-labeling offers a powerful approach to image perfusion in pediatric moyamoya due to transit delay insensitivity. Coupled with pulsed arterial spin-labeling for transit delay information, a volumetric MR imaging approach capturing key DSA information is introduced.
Divya S Bolar - One of the best experts on this subject based on the ideXlab platform.
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comparison of cbf measured with combined velocity selective arterial spin labeling and pulsed arterial spin labeling to blood flow patterns assessed by Conventional Angiography in pediatric moyamoya
American Journal of Neuroradiology, 2019Co-Authors: Divya S Bolar, Darren B Orbach, Borjan Gagoski, Edward R Smith, Elfar Adalsteinsson, P E Grant, Bruce R. Rosen, Richard L RobertsonAbstract:BACKGROUND AND PURPOSE: Imaging CBF is important for managing pediatric moyamoya. Traditional arterial spin-labeling MR imaging detects delayed transit thorough diseased arteries but is inaccurate for measuring perfusion because of these delays. Velocity-selective arterial spin-labeling is insensitive to transit delay and well-suited for imaging Moyamoya perfusion. This study assesses the accuracy of a combined velocity-selective arterial spin-labeling and traditional pulsed arterial spin-labeling CBF approach in pediatric moyamoya, with comparison to blood flow patterns on Conventional Angiography. MATERIALS AND METHODS: Twenty-two neurologically stable pediatric patients with moyamoya and 5 asymptomatic siblings without frank moyamoya were imaged with velocity-selective arterial spin-labeling, pulsed arterial spin-labeling, and DSA (patients). Qualitative comparison was performed, followed by a systematic comparison using ASPECTS-based scoring. Quantitative pulsed arterial spin-labeling CBF and velocity-selective arterial spin-labeling CBF for the middle cerebral artery, anterior cerebral artery, and posterior cerebral artery territories were also compared. RESULTS: Qualitatively, velocity-selective arterial spin-labeling perfusion maps reflect the DSA parenchymal phase, regardless of postinjection timing. Conversely, pulsed arterial spin-labeling maps reflect the DSA appearance at postinjection times closer to the arterial spin-labeling postlabeling delay, regardless of vascular phase. ASPECTS comparison showed excellent agreement (88%, κ = 0.77, P CONCLUSIONS: Velocity-selective arterial spin-labeling offers a powerful approach to image perfusion in pediatric moyamoya due to transit delay insensitivity. Coupled with pulsed arterial spin-labeling for transit delay information, a volumetric MR imaging approach capturing key DSA information is introduced.
Goetz M Richter - One of the best experts on this subject based on the ideXlab platform.
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Radiation Exposure During Uterine Fibroid Embolization (UFE): A Confounder-Controlled Comparison Between a State-of-the-Art Angiography Unit and a Conventional Angiography unit.
RoFo : Fortschritte auf dem Gebiete der Rontgenstrahlen und der Nuklearmedizin, 2017Co-Authors: Christof-matthias Sommer, Wieland Voigt, Michel Klapp Oliger, Christopher L Schlett, Stefan Erpenbach, Katrina Thomas, Andreas Hatopp, Patrick Kurz, Goetz M RichterAbstract:To compare radiation exposure of a state-of-the-art and a Conventional Angiography unit in patients undergoing uterine fibroid embolization (UFE). Between January 2009 and December 2016, 286 patients underwent UFE in our Interdisciplinary Fibroid Center. The inclusion criteria for this retrospective analysis were first-time transarterial embolization for symptomatic fibroids, bilateral embolization, procedures applying a state-of-the-art (Group 1) or a Conventional Angiography unit (Group 2), and bilateral technical success with an adequate embolization endpoint after the injection of microspheres. Study endpoints included radiation exposure, major complications, morphological success (MRI), and clinical success (questionnaire on quality-of-life). Propensity score matching controlled for confounders. The inclusion criteria were met by 58 (Group 1) and 177 (Group 2) patients. After propensity score matching, there was no significant difference between Group 1 (n = 46) and Group 2 (n = 92) regarding age, body-mass index, volume of the dominant fibroid and the uterus, fluoroscopy time, and amount of embolic agent (p ≥ 0.10 each). The dose-area product was significantly lower in Group 1 than in Group 2 (1159.0 cGycm2 vs. 3123.5 cGycm2; p < 0.001), while major complication rates (both groups 0 %) and dominant fibroid devascularization (both groups 100 %) were equal (p > 0.99). There were no significant differences between both groups regarding shrinkage of the dominant fibroid and the uterus and no relevant differences regarding patient-reported quality-of-life. A state-of-the-art Angiography unit has the potential to reduce radiation exposure in patients undergoing UFE without increasing the risk of major complications and with comparably high morphological and clinical success. · A state-of-the-art Angiography unit potentially reduces radiation exposure in patients undergoing UFE.. · Reduced radiation exposure does not seem to negatively influence the rate of major complications.. · Reduced exposure does not seem to negatively affect morphological and clinical success.. · Sommer C, Voigt W, Oliger MK et al. Radiation Exposure During Uterine Fibroid Embolization (UFE): A Confounder-Controlled Comparison Between a State-of-the-Art Angiography Unit and a Conventional Angiography unit. Fortschr Röntgenstr 2018; 190: 250 - 258. © Georg Thieme Verlag KG Stuttgart · New York.
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Radiation Exposure During Uterine Fibroid Embolization (UFE): A Confounder-Controlled Comparison Between a State-of-the-Art Angiography Unit and a Conventional Angiography unit.
Rofo-fortschritte Auf Dem Gebiet Der Rontgenstrahlen Und Der Bildgebenden Verfahren, 2017Co-Authors: Christof-matthias Sommer, Wieland Voigt, Christopher L Schlett, Stefan Erpenbach, Katrina Thomas, Andreas Hatopp, Patrick Kurz, Michel Klapp Oliger, Goetz M RichterAbstract:Purpose To compare radiation exposure of a state-of-the-art and a Conventional Angiography unit in patients undergoing uterine fibroid embolization (UFE). Materials and Methods Between January 2009 and December 2016, 286 patients underwent UFE in our Interdisciplinary Fibroid Center. The inclusion criteria for this retrospective analysis were first-time transarterial embolization for symptomatic fibroids, bilateral embolization, procedures applying a state-of-the-art (Group 1) or a Conventional Angiography unit (Group 2), and bilateral technical success with an adequate embolization endpoint after the injection of microspheres. Study endpoints included radiation exposure, major complications, morphological success (MRI), and clinical success (questionnaire on quality-of-life). Propensity score matching controlled for confounders. Results The inclusion criteria were met by 58 (Group 1) and 177 (Group 2) patients. After propensity score matching, there was no significant difference between Group 1 (n = 46) and Group 2 (n = 92) regarding age, body-mass index, volume of the dominant fibroid and the uterus, fluoroscopy time, and amount of embolic agent (p ≥ 0.10 each). The dose-area product was significantly lower in Group 1 than in Group 2 (1159.0 cGycm2 vs. 3123.5 cGycm2; p 0.99). There were no significant differences between both groups regarding shrinkage of the dominant fibroid and the uterus and no relevant differences regarding patient-reported quality-of-life. Conclusion A state-of-the-art Angiography unit has the potential to reduce radiation exposure in patients undergoing UFE without increasing the risk of major complications and with comparably high morphological and clinical success. Key Points Citation Format
Michael D Dake - One of the best experts on this subject based on the ideXlab platform.
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aortic aneurysmal disease assessment of stent graft treatment ct versus Conventional Angiography
Radiology, 2000Co-Authors: Mark D Armerding, Geoffrey D Rubin, Christopher F Beaulieu, Suzanne M Slonim, Eric W Olcott, Shaun Samuels, M J Jorgensen, Charles P Semba, R B Jeffrey, Michael D DakeAbstract:PURPOSE: To compare computed tomographic (CT) Angiography and Conventional Angiography for determining the success of endoluminal stent-graft treatment of aortic aneurysms. MATERIALS AND METHODS: Forty patients underwent Conventional Angiography and CT Angiography following treatment of aortoiliac aneurysms with endoluminal stent-grafts. Six additional sets of Conventional angiographic–CT angiographic examinations were performed in five patients after placement of additional stent-grafts or coil embolization to treat perigraft leakage. Three faculty CT radiologists who were blinded to patient clinical data and outcome independently interpreted the CT angiograms, and three faculty angiographers, who were not involved in the stent-graft deployment, interpreted the Conventional angiograms. Images were assessed for the presence of postdeployment complications. A reference standard was developed by experienced radiologists using all available images and clinical data. Sensitivities, specificities, and κ values...
Jerzy Szumowski - One of the best experts on this subject based on the ideXlab platform.
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aortic and lower extremity arterial disease evaluation with mr Angiography versus Conventional Angiography
Radiology, 1998Co-Authors: Stephen F. Quinn, Robert C Sheley, Kevin G Semonsen, V J Leonardo, K Y Kojima, Jerzy SzumowskiAbstract:PURPOSE: To compare magnetic resonance (MR) Angiography with Conventional Angiography in evaluation of the aorta and lower-extremity arterial system. MATERIALS AND METHODS: Fifty-seven patients were evaluated with femoral Conventional and MR Angiography. Iliac artery segments were evaluated with two-dimensional and contrast material-enhanced three-dimensional time-of-flight MR Angiography. Infrainguinal regions were evaluated with two-dimensional time-of-flight MR Angiography with a dedicated lower-extremity coil. Arteries depicted on femoral images were separately interpreted as 20 anatomic segments. Disease classification included normal to moderate disease (0%-50% stenosis), severe stenosis (> 50% stenosis), diffuse disease (more than one severe stenosis), and occlusion. Four readers interpreted the images and rendered treatment recommendations. RESULTS: Substantial to almost perfect interobserver agreement (kappa, 0.66-1.00) was achieved in most cases for MR angiogram interpretation. The three most ex...
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Femoral MR Angiography versus Conventional Angiography: preliminary results.
Radiology, 1993Co-Authors: Stephen F. Quinn, Thomas A. Demlow, R W Hallin, L R Eidemiller, Jerzy SzumowskiAbstract:PURPOSE: To develop a bilateral femoral magnetic resonance (MR) angiographic examination that would include the aortic bifurcation to the ankle. MATERIALS AND METHODS: Thirty-seven patients underwent Conventional Angiography and the bilateral femoral MR angiographic examination. Two-dimensional time-of-flight Angiography was used for all studies. RESULTS: The femoral MR angiogram could have replaced the Conventional angiogram in 57% of patients (21 of 37). In 43% of patients (16 of 37), the femoral MR angiogram could not have replaced the Conventional angiogram. Reasons for diagnostic failure with femoral MR Angiography included artifact from vascular clips (n = 8) or prosthetic joints (n = 3), overlooked distal aortic stenosis (n = 1), and suboptimal definition of vessels (usually trifurcation vessels) owing to various causes (n = 8). Seven of the patients in this group had bypass grafts. CONCLUSION: Some of the current limitations of femoral MR Angiography could be avoided by supplemental duplex sonogra...