The Experts below are selected from a list of 93 Experts worldwide ranked by ideXlab platform
Benedicte Dupas - One of the best experts on this subject based on the ideXlab platform.
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ORIGINAL RESEARCH CT Angiography for Brain Death Diagnosis
2015Co-Authors: E. Frampas, M. Videcoq, E. De Kerviler, F. Ricolfi, V. Kuoch, F. Mourey, A. Tenaillon, Benedicte DupasAbstract:BACKGROUND AND PURPOSE: Lack of Cerebral circulation is an important confirmatory test for brain death (BD). Conventional angiography remains the standard imaging method, but CT angiography (CTA) is emerging as an alternative. France accepts BD diagnoses relying on a score based on lack of opacification of 7 intraCerebral vessels in CTA images. The purpose of this study was to validate the efficiency of this score and to evaluate the sensitivity of a novel 4-point CTA score in confirming BD. MATERIALS AND METHODS: A prospective multicentric study was conducted during 12 months with 105 patients referred for CTA to confirm a clinical diagnosis of BD. Clinical data were recorded. CTA images were interpreted first by local radiologists at the referent center, resulting in a 7-point score based on lack of opacification of the pericallosal and cortical segments of the middle Cerebral arteries (MCAs), internal Cerebral Veins (ICVs), and 1 Great Cerebral Vein per patient and, second, by a consensus panel of 3 expert radiologists, blinded to the initial scores, resulting in novel 4-point scores based on the lack of opacification of the cortical segments of the MCAs and ICVs. RESULTS: Injection of contrast medium did not alter renal function. With the initial 7-point score, sensitivity was 62.8%. With the simplified 4-point score, sensitivity was 85.7 % and specificity was 100%. Opacification of ICVs was absent in 98.1 % of patients
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ct angiography for brain death diagnosis
American Journal of Neuroradiology, 2009Co-Authors: E. Frampas, M. Videcoq, E. De Kerviler, F. Ricolfi, V. Kuoch, F. Mourey, A. Tenaillon, Benedicte DupasAbstract:BACKGROUND AND PURPOSE: Lack of Cerebral circulation is an important confirmatory test for brain death (BD). Conventional angiography remains the standard imaging method, but CT angiography (CTA) is emerging as an alternative. France accepts BD diagnoses relying on a score based on lack of opacification of 7 intraCerebral vessels in CTA images. The purpose of this study was to validate the efficiency of this score and to evaluate the sensitivity of a novel 4-point CTA score in confirming BD. MATERIALS AND METHODS: A prospective multicentric study was conducted during 12 months with 105 patients referred for CTA to confirm a clinical diagnosis of BD. Clinical data were recorded. CTA images were interpreted first by local radiologists at the referent center, resulting in a 7-point score based on lack of opacification of the pericallosal and cortical segments of the middle Cerebral arteries (MCAs), internal Cerebral Veins (ICVs), and 1 Great Cerebral Vein per patient and, second, by a consensus panel of 3 expert radiologists, blinded to the initial scores, resulting in novel 4-point scores based on the lack of opacification of the cortical segments of the MCAs and ICVs. RESULTS: Injection of contrast medium did not alter renal function. With the initial 7-point score, sensitivity was 62.8%. With the simplified 4-point score, sensitivity was 85.7% and specificity was 100%. Opacification of ICVs was absent in 98.1% of patients. CONCLUSIONS: Lack of opacification in the cortical segments of the MCAs and internal Veins in CTA is efficient and reliable for confirming BD.
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diagnosis of brain death using two phase spiral ct
American Journal of Neuroradiology, 1998Co-Authors: Benedicte Dupas, M Gayetdelacroix, Daniele Antonioli, M F Veccherini, Daniel Villers, Jean Paul SoulillouAbstract:PURPOSE The purpose of this study was to determine the utility of spiral CT in the diagnosis of brain death. METHODS Spiral CT was evaluated prospectively in 14 brain-dead patients and in 11 healthy subjects. A two-phase protocol was used. Twenty seconds after intravenous injection of a nonionic iodinized contrast medium, the CT table was drawn through the gantry at a rate of 10 mm/s while scanning was in progress. The second scanning phase was started automatically a mean of 54 seconds later, using the same parameters. Opacification or absence of opacification of carotid, vertebral, and basilar arteries and intraCerebral Veins was ascertained for each image in both phases. The diagnosis of brain death was confirmed by elecroencephalography (n = 7), angiography (n = 5), or both (n = 2). Statistical analysis with the Fisher exact test enabled us to compare the brain-dead patients with the healthy control subjects. RESULTS In brain death, the pericallosal and terminal arteries of the cortex did not opacify during the two phases of spiral CT, whereas the superficial temporal arteries were always visible. The internal Cerebral Veins, the Great Cerebral Vein, and the straight sinus did not opacify, whereas the superior ophthalmic Veins were visible on both sides 13 times. For each vessel type, specificity was 100% for nonvascular opacification criteria on the right and left sides. CONCLUSION Two-phase spiral CT can demonstrate the absence of intraCerebral blood flow in brain death.
Irina Mader - One of the best experts on this subject based on the ideXlab platform.
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hemodynamics of Cerebral Veins analyzed by 2d and 4d flow mri and ultrasound in healthy volunteers and patients with multiple sclerosis
Journal of Magnetic Resonance Imaging, 2020Co-Authors: Florian Schuchardt, Christoph Strecker, Johann Lambeck, Thomas Wehrum, Anja Hennemuth, Constantinos Anastasopoulos, Christoph P. Kaller, Irina MaderAbstract:BACKGROUND: Hemodynamic alterations of extracranial Veins are considered an etiologic factor in multiple sclerosis (MS). However, ultrasound and MRI studies could not confirm a pathophysiological link. Because of technical challenges using standard diagnostics, information about the involvement of superficial intracranial Veins in proximity to the affected brain in MS is scarce. PURPOSE: To comprehensively investigate the hemodynamics of intracranial Veins and of the venous outflow tract in MS patients and controls. STUDY TYPE: Prospective. POPULATION: Twenty-eight patients with relapsing-remitting MS (EDSS1.9 ± 1.1; range 0-3) and 41 healthy controls. FIELD STRENGTH/SEQUENCE: 3T/2D phase-contrast and time-resolved 4D flow MRI, extra- and transcranial sonography. ASSESSMENT: Hemodynamics within the superficial and deep intracranial venous system and outflow tract including the internal, basal, and Great Cerebral Vein, straight, superior sagittal, and transverse sinuses, internal jugular and vertebral Veins. Sonography adhered to the chronic cerebrospinal venous insufficiency (CCSVI) criteria. STATISTICAL TESTS: Multivariate repeated measure analysis of variance, Student's two-sample t-test, chi-square, Fisher's exact test; separate analysis of the entire cohort and 32 age- and sex-matched participants. RESULTS: Multi- and univariate main effects of the factor group (MS patient vs. control) and its interactions with the factor vessel position (lower flow within dorsal superior sagittal sinus in MS, 3 ± 1 ml/s vs. 3.8 ± 1 ml/s; P < 0.05) in the uncontrolled cohort were attributable to age-related differences. Age- and sex-matched pairs showed a different velocity gradient in a single segment within the deep Cerebral Veins (Great Cerebral Vein, vena cerebri magna [VCM] 7.6 ± 1.7 cm/s; straight sinus [StS] 10.5 ± 2.2 cm/s vs. volunteers: VCM 9.2 ± 2.3 cm/s; StS 10.2 ± 2.3 cm/s; P = 0.01), reaching comparable velocities instantaneously downstream. Sonography was not statistically different between groups. DATA CONCLUSION: Consistent with previous studies focusing on extracranial hemodynamics, our comprehensive analysis of intraCerebral venous blood flow did not reveal relevant differences between MS patients and controls. Level of Evidence 1. Technical Efficacy Stage 3. J. Magn. Reson. Imaging 2020;51:205-217.
Anja Hennemuth - One of the best experts on this subject based on the ideXlab platform.
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hemodynamics of Cerebral Veins analyzed by 2d and 4d flow mri and ultrasound in healthy volunteers and patients with multiple sclerosis
Journal of Magnetic Resonance Imaging, 2020Co-Authors: Florian Schuchardt, Christoph Strecker, Johann Lambeck, Thomas Wehrum, Anja Hennemuth, Constantinos Anastasopoulos, Christoph P. Kaller, Irina MaderAbstract:BACKGROUND: Hemodynamic alterations of extracranial Veins are considered an etiologic factor in multiple sclerosis (MS). However, ultrasound and MRI studies could not confirm a pathophysiological link. Because of technical challenges using standard diagnostics, information about the involvement of superficial intracranial Veins in proximity to the affected brain in MS is scarce. PURPOSE: To comprehensively investigate the hemodynamics of intracranial Veins and of the venous outflow tract in MS patients and controls. STUDY TYPE: Prospective. POPULATION: Twenty-eight patients with relapsing-remitting MS (EDSS1.9 ± 1.1; range 0-3) and 41 healthy controls. FIELD STRENGTH/SEQUENCE: 3T/2D phase-contrast and time-resolved 4D flow MRI, extra- and transcranial sonography. ASSESSMENT: Hemodynamics within the superficial and deep intracranial venous system and outflow tract including the internal, basal, and Great Cerebral Vein, straight, superior sagittal, and transverse sinuses, internal jugular and vertebral Veins. Sonography adhered to the chronic cerebrospinal venous insufficiency (CCSVI) criteria. STATISTICAL TESTS: Multivariate repeated measure analysis of variance, Student's two-sample t-test, chi-square, Fisher's exact test; separate analysis of the entire cohort and 32 age- and sex-matched participants. RESULTS: Multi- and univariate main effects of the factor group (MS patient vs. control) and its interactions with the factor vessel position (lower flow within dorsal superior sagittal sinus in MS, 3 ± 1 ml/s vs. 3.8 ± 1 ml/s; P < 0.05) in the uncontrolled cohort were attributable to age-related differences. Age- and sex-matched pairs showed a different velocity gradient in a single segment within the deep Cerebral Veins (Great Cerebral Vein, vena cerebri magna [VCM] 7.6 ± 1.7 cm/s; straight sinus [StS] 10.5 ± 2.2 cm/s vs. volunteers: VCM 9.2 ± 2.3 cm/s; StS 10.2 ± 2.3 cm/s; P = 0.01), reaching comparable velocities instantaneously downstream. Sonography was not statistically different between groups. DATA CONCLUSION: Consistent with previous studies focusing on extracranial hemodynamics, our comprehensive analysis of intraCerebral venous blood flow did not reveal relevant differences between MS patients and controls. Level of Evidence 1. Technical Efficacy Stage 3. J. Magn. Reson. Imaging 2020;51:205-217.
Constantinos Anastasopoulos - One of the best experts on this subject based on the ideXlab platform.
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hemodynamics of Cerebral Veins analyzed by 2d and 4d flow mri and ultrasound in healthy volunteers and patients with multiple sclerosis
Journal of Magnetic Resonance Imaging, 2020Co-Authors: Florian Schuchardt, Christoph Strecker, Johann Lambeck, Thomas Wehrum, Anja Hennemuth, Constantinos Anastasopoulos, Christoph P. Kaller, Irina MaderAbstract:BACKGROUND: Hemodynamic alterations of extracranial Veins are considered an etiologic factor in multiple sclerosis (MS). However, ultrasound and MRI studies could not confirm a pathophysiological link. Because of technical challenges using standard diagnostics, information about the involvement of superficial intracranial Veins in proximity to the affected brain in MS is scarce. PURPOSE: To comprehensively investigate the hemodynamics of intracranial Veins and of the venous outflow tract in MS patients and controls. STUDY TYPE: Prospective. POPULATION: Twenty-eight patients with relapsing-remitting MS (EDSS1.9 ± 1.1; range 0-3) and 41 healthy controls. FIELD STRENGTH/SEQUENCE: 3T/2D phase-contrast and time-resolved 4D flow MRI, extra- and transcranial sonography. ASSESSMENT: Hemodynamics within the superficial and deep intracranial venous system and outflow tract including the internal, basal, and Great Cerebral Vein, straight, superior sagittal, and transverse sinuses, internal jugular and vertebral Veins. Sonography adhered to the chronic cerebrospinal venous insufficiency (CCSVI) criteria. STATISTICAL TESTS: Multivariate repeated measure analysis of variance, Student's two-sample t-test, chi-square, Fisher's exact test; separate analysis of the entire cohort and 32 age- and sex-matched participants. RESULTS: Multi- and univariate main effects of the factor group (MS patient vs. control) and its interactions with the factor vessel position (lower flow within dorsal superior sagittal sinus in MS, 3 ± 1 ml/s vs. 3.8 ± 1 ml/s; P < 0.05) in the uncontrolled cohort were attributable to age-related differences. Age- and sex-matched pairs showed a different velocity gradient in a single segment within the deep Cerebral Veins (Great Cerebral Vein, vena cerebri magna [VCM] 7.6 ± 1.7 cm/s; straight sinus [StS] 10.5 ± 2.2 cm/s vs. volunteers: VCM 9.2 ± 2.3 cm/s; StS 10.2 ± 2.3 cm/s; P = 0.01), reaching comparable velocities instantaneously downstream. Sonography was not statistically different between groups. DATA CONCLUSION: Consistent with previous studies focusing on extracranial hemodynamics, our comprehensive analysis of intraCerebral venous blood flow did not reveal relevant differences between MS patients and controls. Level of Evidence 1. Technical Efficacy Stage 3. J. Magn. Reson. Imaging 2020;51:205-217.
Malgorzata Burzynska - One of the best experts on this subject based on the ideXlab platform.
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computed tomographic angiography criteria in the diagnosis of brain death comparison of sensitivity and interobserver reliability of different evaluation scales
Neuroradiology, 2014Co-Authors: Marcin Sawicki, R Bohatyrewicz, Krzysztof Safranow, Anna Walecka, Jerzy Walecki, Olgierd Rowinski, Joanna Solekpastuszka, Z Czajkowski, Maciej Guzinski, Malgorzata BurzynskaAbstract:The standardized diagnostic criteria for computed tomographic angiography (CTA) in diagnosis of brain death (BD) are not yet established. The aim of the study was to compare the sensitivity and interobserver agreement of the three previously used scales of CTA for the diagnosis of BD. Eighty-two clinically brain-dead patients underwent CTA with a delay of 40 s after contrast injection. Catheter angiography was used as the reference standard. CTA results were assessed by two radiologists, and the diagnosis of BD was established according to 10-, 7-, and 4-point scales. Catheter angiography confirmed the diagnosis of BD in all cases. Opacification of certain Cerebral vessels as indicator of BD was highly sensitive: cortical segments of the middle Cerebral artery (96.3 %), the internal Cerebral Vein (98.8 %), and the Great Cerebral Vein (98.8 %). Other vessels were less sensitive: the pericallosal artery (74.4 %), cortical segments of the posterior Cerebral artery (79.3 %), and the basilar artery (82.9 %). The sensitivities of the 10-, 7-, and 4-point scales were 67.1, 74.4, and 96.3 %, respectively (p < 0.001). Percentage interobserver agreement in diagnosis of BD reached 93 % for the 10-point scale, 89 % for the 7-point scale, and 95 % for the 4-point scale (p = 0.37). In the application of CTA to the diagnosis of BD, reducing the assessment of vascular opacification scale from a 10- to a 4-point scale significantly increases the sensitivity and maintains high interobserver reliability.
