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

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

In Vivo Tracking of the Human Patella Using Cine Phase Contrast Magnetic Resonance Imaging

1999 ◽  
Vol 121 (6) ◽  
pp. 650-656 ◽  
Author(s):  
F. T. Sheehan ◽  
F. E. Zajac ◽  
J. E. Drace
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Knee Joint ◽  
Phase Contrast ◽  
Three Dimensional ◽  
Resonance Imaging ◽  
Contrast Magnetic Resonance ◽  
Knee Joint Kinematics ◽  
Cine Phase Contrast

Improper patellar tracking is often considered to be the cause of patellar-femoral pain. Unfortunately, our knowledge of patellar-femoral-tibial (knee) joint kinematics is severely limited due to a lack of three-dimensional, noninvasive, in vivo measurement techniques. This study presents the first large-scale, dynamic, three-dimensional, noninvasive, in vivo study of nonimpaired knee joint kinematics during volitional leg extensions. Cine-phase contrast magnetic resonance imaging was used to measure the velocity profiles of the patella, femur, and tibia in 18 unimpaired knees during leg extensions, resisted by a 34 N weight. Bone displacements were calculated through integration and then converted into three-dimensional orientation angles. We found that the patella displaced laterally, superiorly, and anteriorly as the knee extended. Further, patellar flexion lagged knee flexion, patellar tilt was variable, and patellar rotation was fairly constant throughout extension.

scholarly journals Aging Effects on Cerebral Blood and Cerebrospinal Fluid Flows

2007 ◽  
Vol 27 (9) ◽  
pp. 1563-1572 ◽  
Author(s):  
Souraya Stoquart-ElSankari ◽  
Olivier Balédent ◽  
Catherine Gondry-Jouet ◽  
Malek Makki ◽  
Olivier Godefroy ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Blood Flow ◽  
Cerebrospinal Fluid ◽  
Magnetic Resonance ◽  
Phase Contrast ◽  
The Elderly ◽  
Elderly Group ◽  
Resonance Imaging ◽  
Aging Effects ◽  
Contrast Magnetic Resonance

Phase-contrast magnetic resonance imaging (PC-MRI) is a noninvasive reliable technique, which enables quantification of cerebrospinal fluid (CSF) and total cerebral blood flows (tCBF). Although it is used to study hydrodynamic cerebral disorders in the elderly group (hydrocephalus), there is no published evaluation of aging effects on both tCBF and CSF flows, and on their mechanical coupling. Nineteen young (mean age 27 ± 4 years) and 12 elderly (71 ± 9 years) healthy volunteers underwent cerebral MRI using 1.5 T scanner. Phase-contrast magnetic resonance imaging pulse sequence was performed at the aqueductal and cervical levels. Cerebrospinal fluid and blood flow curves were then calculated over the cardiac cycle, to extract the characteristic parameters: mean and peak flows, their latencies, and stroke volumes for CSF (cervical and aqueductal) and vascular flows. Total cerebral blood flow was ( P < 0.01) decreased significantly in the elderly group when compared with the young subjects with a linear correlation with age observed only in the elderly group ( R2 = 0.7; P = 0.05). Arteriovenous delay was preserved with aging. The CSF stroke volumes were significantly reduced in the elderly, at both aqueductal ( P < 0.01) and cervical ( P < 0.05) levels, whereas aqueduct/cervical proportion ( P = 0.9) was preserved. This is the first work to study aging effects on both CSF and vascular cerebral flows. Data showed (1) tCBF decrease, (2) proportional aqueductal and cervical CSF pulsations reduction as a result of arterial loss of pulsatility, and (3) preserved intracerebral compliance with aging. These results should be used as reference values, to help understand the pathophysiology of degenerative dementia and cerebral hydrodynamic disorders as hydrocephalus.

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