Do Hemorheological Properties Influence Vasomotor Reactivity of the Brain Arteries? A Transcranial Doppler Study During Hypo-, Normo- and Hypercapnia

1987 ◽  
pp. 452-458 ◽  
Author(s):  
E. B. Ringelstein ◽  
W. Grosse ◽  
A. Mauckner ◽  
R. Schneider ◽  
W. M. Glöckner ◽  
...  
Keyword(s):  
Transcranial Doppler ◽  
Vasomotor Reactivity ◽  
Doppler Study ◽  
Brain Arteries ◽  
The Brain

Cerebral hemodynamics in angioma patients: an intraoperative study

1987 ◽  
Vol 67 (6) ◽  
pp. 822-831 ◽  
Author(s):  
Werner Hassler ◽  
Helmuth Steinmetz
Keyword(s):  
Doppler Sonography ◽  
Perfusion Pressure ◽  
Normal Brain ◽  
Content Type ◽  
Vasomotor Reactivity ◽  
Brain Arteries ◽  
Normal Perfusion Pressure Breakthrough ◽  
The Brain ◽  
Intravascular Pressure ◽  
Flow Velocities

✓ Local hemodynamics were investigated during 33 operations for cerebral arteriovenous malformation (AVM). In all cases, microvascular Doppler sonography was used to measure flow velocities and vasomotor reactivity to CO2 changes. Intravascular pressure recordings were performed in six patients. The AVM feeders had low intravascular pressure, high flow velocity, low peripheral stream resistance, and very poor vasomotor reactivity. Remote brain arteries showed no abnormalities. Doppler findings in arterial branches of AVM feeders that supplied normal brain indicated arteriolar dilation in their peripheral distribution. On removal of the angiomas, the arteries that formerly supplied them showed a return to normal intravascular pressure, whereas flow velocities dropped far below normal in these vessels. Remote arteries and branches of the former AVM feeders supplying the brain did not show any signs of impaired vasomotor reactivity following angioma removal. The results are in contrast to the normal perfusion pressure breakthrough theory.

A Transcranial Doppler Study of Vasomotor Reactivity in Symptomatic Carotid Occlusion

1993 ◽  
Vol 3 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Leandro Provinciali ◽  
Maria Gabriella Ceravolo ◽  
Paolo Minciotti
Keyword(s):  
Transcranial Doppler ◽  
Carotid Occlusion ◽  
Symptomatic Carotid ◽  
Vasomotor Reactivity ◽  
Doppler Study

scholarly journals Blood flow velocity and vasomotor reactivity in patients with arteriovenous malformations. A transcranial Doppler study.

Stroke ◽  
1994 ◽  
Vol 25 (8) ◽  
pp. 1574-1580 ◽  
Author(s):  
R R Diehl ◽  
H Henkes ◽  
H C Nahser ◽  
D Kühne ◽  
P Berlit
Keyword(s):  
Blood Flow ◽  
Flow Velocity ◽  
Transcranial Doppler ◽  
Blood Flow Velocity ◽  
Arteriovenous Malformations ◽  
Vasomotor Reactivity ◽  
Doppler Study

scholarly journals Cerebral vasomotor reactivity in border zone infarcts; a transcranial Doppler study

2019 ◽  
Vol 55 (1) ◽  
Author(s):  
Hossam Afify ◽  
Shahinaz M. Helmy ◽  
Lobna M. El-Nabil ◽  
Naglaa M. El-khayat ◽  
Nevine M. El Nahas ◽  
...  
Keyword(s):  
Transcranial Doppler ◽  
Border Zone ◽  
Vasomotor Reactivity ◽  
Doppler Study ◽  
Cerebral Vasomotor Reactivity

Microvascular features that suggest effectors of blood-flow regulation in the brain: Evidence by SEM of corrosion casts of intracerebral vessels

1990 ◽  
Vol 48 (3) ◽  
pp. 274-275
Author(s):  
Enrico D.F. Motti ◽  
Hans-Georg Imhof ◽  
Gazi M. Yasargil
Keyword(s):  
Blood Flow ◽  
Perfusion Pressure ◽  
Corrosion Casts ◽  
Cerebral Microcirculation ◽  
Pial Arteries ◽  
Random Occurrence ◽  
Brain Arteries ◽  
Homogeneous Network ◽  
The Brain

Physiologists have devoted most attention in the cerebrovascular tree to the arterial side of the circulation which has been subdivided in three levels: 1) major brain arteries which keep microcirculation constant despite changes in perfusion pressure; 2) pial arteries supposed to be effectors regulating microcirculation; 3) intracerebral arteries supposed to be deprived of active cerebral blood flow regulating devices.The morphological search for microvascular effectors in the cerebrovascular bed has been elusive. The opaque substance of the brain confines in vivo investigation to the superficial pial arteries. Most morphologists had to limit their observation to the random occurrence of a favorable site in the practically two-dimensional thickness of diaphanized histological sections. It is then not surprising most investigators of the cerebral microcirculation refer to an homogeneous network of microvessels interposed between arterioles and venules.We have taken advantage of the excellent depth of focus afforded by the scanning electron microscope (SEM) to investigate corrosion casts obtained injecting a range of experimental animals with a modified Batson's acrylic mixture.

Cerebrovascular reactivity in hypertensive patients: A transcranial doppler study

1997 ◽  
Vol 25 (7) ◽  
pp. 383-389 ◽  
Author(s):  
Andrea Ficzere ◽  
Attila Valikovics ◽  
Béla Fülesdi ◽  
Attila Juhász ◽  
István Czuriga ◽  
...  
Keyword(s):  
Transcranial Doppler ◽  
Cerebrovascular Reactivity ◽  
Hypertensive Patients ◽  
Doppler Study

THE EFFECT OF AGE ON THE ELASTICITY OF THE MAJOR BRAIN ARTERIES

1965 ◽  
Vol 43 (2) ◽  
pp. 185-202 ◽  
Author(s):  
Douglas E. Busby ◽  
Alan C. Burton
Keyword(s):  
High Pressures ◽  
Mean Value ◽  
Collagen Fibers ◽  
Peripheral Arteries ◽  
Volume Data ◽  
Maximum Slope ◽  
Brain Arteries ◽  
Autopsy Specimens ◽  
Collagenous Fibers ◽  
The Brain

In previous work on peripheral arteries the law of Laplace has been applied to the pressure–volume data to yield the elastic constants and interrelation of function of elastin and collagenous fibers in the wall, and the changes with age. Similar analysis of major brain arteries has been made on autopsy specimens, aged 2 to 90. Volume (micrometer syringe) and pressure (electromanometer) in arterial segments were accurately measured. Absolute volumes were obtained by collapsing the artery with negative pressure, and the "unstretched circumferences" of the vessel were deduced from the curves. Tension–circumference curves were constructed. These showed the characteristic increasing slope (increased "elastance" or "stiffness") with increasing degree of stretch, interpreted as successive "recruitment" of collagen fibers as they reach their unstretched length.Increases in arterial length with distension were very small and negligible in vessels older than 30 years. Maximum slope (stiffness) was reached at pressures in the physiological range. The maximal stretch was 26 to 38% for vessels aged 30 to 90 years. This is less than for peripheral arteries, except those over 80 years old.Ageing showed itself mainly in reduction of the stretch required to bring 50% of the collagen fibers to their unstretched length, i.e. in the "degree of slackness". This was 30% stretch for younger vessels, 20% for the older. Unlike the peripheral arteries, the brain arteries show no significant increase with age in the maximal stiffness (related to their total collagen content). The mean value of the Young's modulus of the wall at high pressures was 1.93 ± 0.67 × 107 dynes/sq.cm. No significant change in thickness of the wall or lumen diameter with age was found.It is concluded that the major brain arteries are less distensible than peripheral arteries of comparable diameter, particularly in youth. Distensibility decreases with age, mainly because the "degree of slackness" of the collagen fibers is reduced. At physiological pressures the major resistance to distension is due to the collagen fibers rather than to the elastin fibers, which appear histologically to be less abundant, except in the elastica interna, than in peripheral arteries.

Cerebral autoregulation is preserved in multiple system atrophy: A transcranial Doppler study

2006 ◽  
Vol 21 (12) ◽  
pp. 2122-2126 ◽  
Author(s):  
Anne Pavy-Le Traon ◽  
Richard L. Hughson ◽  
Claire Thalamas ◽  
Monique Galitsky ◽  
Nelly Fabre ◽  
...  
Keyword(s):  
Multiple System Atrophy ◽  
Transcranial Doppler ◽  
Cerebral Autoregulation ◽  
Doppler Study
Sign in / Sign up

Export Citation Format

Share Document