503 Velocity profile of blood flow in the ascending aorta : Measurement with cine phase-contrast MR imaging

This prospective study investigated the effects of fold-over oversampling on phase-offset background errors with 2D-Cine phase contrast (Cine-PC) magnetic resonance imaging (MRI). It was performed on brain MRI and compared to conventional Full-field of view FOV coverage and it was tested with two different velocity encoding (Venc) values. We chose Venc = 100 mm/s to encode cerebrospinal fluid (CSF) flows in the aqueduct and 600 mm/s to encode blood flow in the carotid artery. Cine-PC was carried out on 10 healthy adult volunteers followed simultaneously by an acquisition on static agar-gel phantom to measure the phase-offset background errors. Pixel-wise correction of both the CSF and the blood flows was calculated through 32 points of the cardiac-cycle. We compared the velocity-to-noise ratio, the section area, the absolute and the corrected velocity (peak; mean and minimum), the net flow, and the stroke volume before and after correction. We performed the statistical T-test to compare Full-FOV and fold-over and Bland–Altman plots to analyze their differences. Our results showed that following phase-offset error correction, the blood stroke-volume was significantly higher with Full-FOV compared to fold-over. We observed a significantly higher CSF mean velocity and net flow values in the fold-over option. Compared to Full-FOV, fold-over provides a significantly larger section area and significantly lower peak velocity-offset in the aqueduct. No significant difference between the two coverages was reported before and after phase-offset in blood flow measurements. In conclusion, fold-over oversampling can be chosen as an alternative to increase spatial resolution and accurate cerebral flow quantification in Cine-PC.

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Portal blood flow in the presence or absence of diffuse liver disease: measurement by phase contrast MR imaging

Abdominal Imaging ◽

10.1007/bf00200392 ◽

1995 ◽

Vol 20 (3) ◽

pp. 197-200 ◽

Cited By ~ 15

Author(s):

N. Kashitani ◽

S. Kimoto ◽

M. Tsunoda ◽

T. Ito ◽

T. Tsuji ◽

...

Keyword(s):

Blood Flow ◽

Liver Disease ◽

Mr Imaging ◽

Phase Contrast ◽

Portal Blood Flow ◽

Portal Blood ◽

Diffuse Liver Disease

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Phase-Contrast Cine Mr Imaging of Normal Aqueductal CSF Flow

Acta Radiologica ◽

10.1177/028418519403500204 ◽

1994 ◽

Vol 35 (2) ◽

pp. 123-130 ◽

Cited By ~ 51

Author(s):

F. Barkhof ◽

M. Kouwenhoven ◽

P. Scheltens ◽

M. Sprenger ◽

P. Algra ◽

...

Keyword(s):

Mr Imaging ◽

Phase Contrast ◽

Volume Averaging ◽

Cortical Atrophy ◽

Csf Flow ◽

Caudal Direction ◽

Cine Mr ◽

Flow Void ◽

Phantom Studies ◽

Cine Phase Contrast

Cine phase-contrast MR imaging was used to study pulsatile CSF flow in the aqueduct in 11 young controls (mean age 30 years) and 9 old controls (mean age 69 years). A high-resolution gradient echo technique and an oblique imaging plane, perpendicular to the aqueduct, was used to avoid volume averaging. Phantom studies confirmed that the technique was accurate. Aqueductal velocity and flux in old controls was higher than in young controls, but the differences were not significant. For all controls together, the averaged peak velocity was 4.2 ± 1.5 cm/s in rostral and −7.8 ± 4.9 cm/s in caudal direction; for the flux it was 0.16 ± 0.10 cm3/s in rostral and −0.29 ± 0.19 cm3/s in caudal direction. Phase-contrast measurements were significantly related to flow-void on modulus MR images, but not with ventricular size or cortical atrophy. The present technique avoids underestimation of aqueductal flow, and therefore reveals higher aqueductal velocity and flux values than previous studies. Factors other than age or atrophy seem to determine aqueductal CSF flow.

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Prospective assessment of decreased azygos blood flow after oral administration of non-selective beta-blocker, quantified by 2D cine phase-contrast magnetic resonance imaging.

10.26226/morressier.5b040f11d64f25001b0ecd04 ◽

2018 ◽

Author(s):

Paul Bazeries

Keyword(s):

Magnetic Resonance Imaging ◽

Blood Flow ◽

Magnetic Resonance ◽

Oral Administration ◽

Beta Blocker ◽

Phase Contrast ◽

Resonance Imaging ◽

Contrast Magnetic Resonance ◽

Prospective Assessment ◽

Cine Phase Contrast

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Phase-Contrast MRI Indices can Reflect Intracranial Compliance Deterioration Induced by Intra-Abdominal/ Thoracic Hypertension

10.21203/rs.3.rs-150802/v1 ◽

2021 ◽

Author(s):

Jie Feng ◽

Xiao Yu ◽

Jie Liu ◽

Wenjia Liu ◽

Lin Ma

Keyword(s):

Blood Flow ◽

Phase Contrast ◽

Trauma Patients ◽

Phase Contrast Mri ◽

Time To Peak ◽

Intracranial Compliance ◽

Cross Section Area ◽

Section Area ◽

Abdominal Hypertension ◽

Cine Phase Contrast

Abstract BackgroundIdentifying elevated intracranial pressure (ICP) and decreased intracranial compliance (ICC) is imperative for optimizing patient management in neurocritical care settings. Intra-abdominal hypertension (IAH) and intrathoracic hypertension (ITH) is common in trauma patients, which affects homeostasis of ICP/ICC. Knowledge of this effects is little and monitoring this effect is difficult. In the current study, we examined whether the indices generated from 2D cine phase contrast MRI (2D cine PC-MRI) could reflect ICC/ICP alterations induced by elevated IAH/ITH during VM.MethodsA total of 50 healthy young volunteers participated in this study (male: female = 24:26), and took a 2D cine PC-MRI during normal breath and VM respectively. Cross-section area (CSA) of dominant IJV and ipsilateral ICA, the maximum blood flow (Fmax), minimum blood flow (Fmin), mean blood flow (MBF), pulsatility index (PI), arteriovenous delay (AVD) and time to peak of arterial pulse (TTP) were gauged from images or calculated from the blood flow curves generated from 2D cine PC-MRI. ResultsDuring VM state, in comparison to NB, CSAIJV increased significantly (p<0.0001), indicating an elevation of cerebral venous outflow resistance; Fmax_ICA, Fmax_IJV, Fmean_ICA and Fmean_IJV decreased significantly (p<0.0001, p<0.0001, p<0.001, p<0.0001, respectively); PI_ICA and PI_IJV decreased significantly (p<0.0001, p<0.0001); both absolute and normalized AVD decreased significantly (p<0.0001, p<0.0001), while absolute and normalized TTP increased significantly (p=0.0329, p=0.0376).Conclusions Indices generated from 2D cine PC-MRI, especially AVD and TTP, can reveal the ICC/ICP dynamics induced by elevated IAP/ITP. These indices have potential clinical application in ICC/ICP monitoring in patients who was speculated with an IAH or ITH.

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