Doppler-Assessed Cerebral Blood Flow Velocity in the Neonate as Estimator of Global Cerebral Blood Volume Flow Measured Using Phase-Contrast Magnetic Resonance Angiography

Neonatology ◽  
2013 ◽  
Vol 103 (1) ◽  
pp. 21-26 ◽  
Author(s):  
Manon J.N.L. Benders ◽  
Jeroen Hendrikse ◽  
Linda de Vries ◽  
Floris Groenendaal ◽  
Frank van Bel
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Magnetic Resonance ◽  
Magnetic Resonance Angiography ◽  
Blood Flow Velocity ◽  
Phase Contrast ◽  
Cerebral Blood Volume ◽  
Cerebral Blood Flow Velocity ◽  
Volume Flow ◽  
Contrast Magnetic Resonance

Cerebral blood flow velocity underestimates cerebral blood flow during modest hypercapnia and hypocapnia

2014 ◽  
Vol 117 (10) ◽  
pp. 1090-1096 ◽  
Author(s):  
Nicole S. Coverdale ◽  
Joseph S. Gati ◽  
Oksana Opalevych ◽  
Amanda Perrotta ◽  
J. Kevin Shoemaker
Keyword(s):  
Carbon Dioxide ◽  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Magnetic Resonance ◽  
Flow Velocity ◽  
Blood Flow Velocity ◽  
Cerebral Blood Flow Velocity ◽  
Intraclass Correlation ◽  
Magnetic Resonance Images ◽  
Carbon Dioxide Partial Pressure

To establish the accuracy of transcranial Doppler ultrasound (TCD) measures of middle cerebral artery (MCA) cerebral blood flow velocity (CBFV) as a surrogate of cerebral blood flow (CBF) during hypercapnia (HC) and hypocapnia (HO), we examined whether the cross-sectional area (CSA) of the MCA changed during HC or HO and whether TCD-based estimates of CBFV were equivalent to estimates from phase contrast (PC) magnetic resonance imaging. MCA CSA was measured from 3T magnetic resonance images during baseline, HO (hyperventilation at 30 breaths/min), and HC (6% carbon dioxide). PC and TCD measures of CBFV were measured during these protocols on separate days. CSA and TCD CBFV were used to calculate CBF. During HC, CSA increased from 5.6 ± 0.8 to 6.5 ± 1.0 mm2 ( P < 0.001, n = 13), while end-tidal carbon dioxide partial pressure (PetCO2) increased from 37 ± 3 to 46 ± 5 Torr ( P < 0.001). During HO, CSA decreased from 5.8 ± 0.9 to 5.3 ± 0.9 mm2 ( P < 0.001, n = 15), while PetCO2 decreased from 36 ± 4 to 23 ± 3 Torr ( P < 0.001). CBFVs during baseline, HO, and HC were compared between PC and TCD, and the intraclass correlation coefficient was 0.83 ( P < 0.001). The relative increase from baseline was 18 ± 8% greater ( P < 0.001) for CBF than TCD CBFV during HC, and the relative decrease of CBF during HO was 7 ± 4% greater than the change in TCD CBFV ( P < 0.001). These findings challenge the assumption that the CSA of the MCA does not change over modest changes in PetCO2.

scholarly journals Inter- and Intra-Rater Reliability of Individual Cerebral Blood Flow Measured by Quantitative Vessel-Flow Phase-Contrast MRI

2020 ◽  
Vol 9 (10) ◽  
pp. 3099
Author(s):  
Kwang-Hwa Chang ◽  
Yuan-Hao Lee ◽  
Chia-Yuen Chen ◽  
Ming-Fang Lin ◽  
Ying Chin Lin ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Magnetic Resonance ◽  
Magnetic Resonance Angiography ◽  
Correlation Coefficient ◽  
Cerebral Artery ◽  
Phase Contrast ◽  
Cerebral Arteries ◽  
Intraclass Correlation ◽  
Vessel Flow

Vessel flow quantification by two-dimensional (2D) phase-contrast magnetic resonance imaging (PC-MRI) using a three-dimensional (3D) magnetic resonance angiography (MRA) model to measure cerebral blood flow has unclear analytical reliability. The present study aimed to determine the inter- and intra-rater reliability of quantitative vessel-flow PC-MRI and potential factors influencing its consistency. We prospectively recruited 30 Asian participants (aged 20–90 years; 16 women; 22 healthy and 8 stroke patients) for performing 1.5-T MR equipped with a head coil. Each participant was first scanned for time-of-flight magnetic resonance angiography (TOF-MRA) images for localization of intracranial arteries. The 2D PC-MRI for each cerebral artery (total 13 arteries in fixed order) was performed twice by two well-trained operators in optimal position. Using the same 3D MRA as a map and facilitated with the non-invasive optimal vessel analysis (NOVA) system, each scan was taken on a plane perpendicular to the target artery. Two consecutive full 13-artery scans were performed at least 15 min apart after participants were removed from the scanner table and then repositioned. A total of four PC flow images obtained from each target artery were transmitted to a workstation facilitated with the NOVA system. Flow data were calculated semi-automatically by the NOVA system after a few simple steps. Two-way mixed-effect models and standard errors of measurements were used. In 13 cerebral arteries, repeatability, using the intra-rater estimate expressed as the average-measures intraclass correlation coefficient, ranged from 0.641 to 0.954, and reproducibility, using the inter-rater estimate, ranged from 0.672 to 0.977. Except in the middle cerebral artery and the distal segment of the anterior cerebral artery, repeatability and reproducibility were excellent (intraclass correlation coefficient exceeded 0.8). The use of quantitative vessel-flow PC-MRI is a precise means to measure blood flow in most target cerebral arteries. This was evidenced by inter-rater and intra-rater correlations that were good/excellent, indicating good reproducibility and repeatability.

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