An evaluation of the use of cerebral blood volume measurements as an index of change in cerebral blood flow

To evaluate changes in cerebral hemodynamics and metabolism induced by acetazolamide in healthy subjects, positron emission tomography studies for measurement of cerebral perfusion and oxygen consumption were performed. Sixteen healthy volunteers underwent positron emission tomography studies with15O-gas and water before and after intravenous administration of acetazolamide. Dynamic positron emission tomography data were acquired after bolus injection of H215O and bolus inhalation of15O2. Cerebral blood flow, metabolic rate of oxygen, and arterial-to-capillary blood volume images were calculated using the three-weighted integral method. The images of cerebral blood volume were calculated using the bolus inhalation technique of C15O. The scans for cerebral blood flow and volume and metabolic rate of oxygen after acetazolamide challenge were performed at 10, 20, and 30 minutes after drug injection. The parametric images obtained under the two conditions at baseline and after acetazolamide administration were compared. The global and regional values for cerebral blood flow and volume and arterial-to-capillary blood volume increased significantly after acetazolamide administration compared with the baseline condition, whereas no difference in metabolic rate of oxygen was observed. Acetazolamide-induced increases in both blood flow and volume in the normal brain occurred as a vasodilatory reaction of functioning vessels. The increase in arterial-to-capillary blood volume made the major contribution to the cerebral blood volume increase, indicating that the raise in cerebral blood flow during the acetazolamide challenge is closely related to arterial-to-capillary vasomotor responsiveness.

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Early changes measured by magnetic resonance imaging in cerebral blood flow, blood volume, and blood-brain barrier permeability following dexamethasone treatment in patients with brain tumors

Journal of Neurosurgery ◽

10.3171/jns.1999.90.2.0300 ◽

1999 ◽

Vol 90 (2) ◽

pp. 300-305 ◽

Cited By ~ 127

Author(s):

Leif Østergaard ◽

Fred H. Hochberg ◽

James D. Rabinov ◽

A. Gregory Sorensen ◽

Michael Lev ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Magnetic Resonance ◽

Brain Tumors ◽

Mr Imaging ◽

Blood Volume ◽

Cerebral Blood Volume ◽

Clinical Effects ◽

Content Type ◽

Fine Print

Object. In this study the authors assessed the early changes in brain tumor physiology associated with glucocorticoid administration. Glucocorticoids have a dramatic effect on symptoms in patients with brain tumors over a time scale ranging from minutes to a few hours. Previous studies have indicated that glucocorticoids may act either by decreasing cerebral blood volume (CBV) or blood-tumor barrier (BTB) permeability and thereby the degree of vasogenic edema.Methods. Using magnetic resonance (MR) imaging, the authors examined the acute changes in CBV, cerebral blood flow (CBF), and BTB permeability to gadolinium-diethylenetriamine pentaacetic acid after administration of dexamethasone in six patients with brain tumors. In patients with acute decreases in BTB permeability after dexamethasone administration, changes in the degree of edema were assessed using the apparent diffusion coefficient of water.Conclusions. Dexamethasone was found to cause a dramatic decrease in BTB permeability and regional CBV but no significant changes in CBF or the degree of edema. The authors found that MR imaging provides a powerful tool for investigating the pathophysiological changes associated with the clinical effects of glucocorticoids.

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Ultrasonographic measurement of cerebral blood flow, cerebral circulation time and cerebral blood volume in vascular and Alzheimer’s dementia

Journal of Neurology ◽

10.1007/s00415-005-0826-8 ◽

2005 ◽

Vol 252 (10) ◽

pp. 1171-1177 ◽

Cited By ~ 15

Author(s):

S. J. Schreiber ◽

F. Doepp ◽

E. Spruth ◽

U. A. Kopp ◽

J. M. Valdueza

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Blood Volume ◽

Cerebral Circulation ◽

Cerebral Blood Volume ◽

Alzheimer’S Dementia ◽

Circulation Time ◽

Alzheimer's Dementia ◽

Cerebral Circulation Time

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Can Cerebral Blood Volume Be Measured Reproducibly with an Improved near Infrared Spectroscopy System?

Journal of Cerebral Blood Flow & Metabolism ◽

10.1097/00004647-200102000-00002 ◽

2001 ◽

Vol 21 (2) ◽

pp. 110-113 ◽

Cited By ~ 15

Author(s):

Marjo J. T. Van de Ven ◽

Willy N. J. M. Colier ◽

Marco C. van der Sluijs ◽

Diederik Walraven ◽

Berend Oeseburg ◽

...

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Infrared Spectroscopy ◽

Blood Volume ◽

Near Infrared Spectroscopy ◽

Healthy Subjects ◽

Baseline Level ◽

Near Infrared ◽

Cerebral Blood Volume ◽

Spectroscopy System

In some circumstances, cerebral blood volume (CBV) can be used as a measure for cerebral blood flow. A new near infrared spectroscope was used for determining the reproducibility of CBV measurements assessed by the O2-method. Twenty-seven healthy subjects were investigated. An intrasubject coefficient of variation (CV) was calculated, based on four identical episodes of desaturation–resaturation (O2-method) procedures for CBV measurements. Two trials were performed, with (trial 1) and without (trial 2) disconnecting the equipment. A mean CV of 12.6% and 10.0% was found in trial 1 and 2, respectively. Cerebral blood volume values yield 3.60 ± 0.82 mL 100 g−1. Cerebral blood volume could be measured reproducible in adults using near infrared spectroscopy, if the arterial desaturation is limited to approximately 5% from baseline level.

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159. Perfusion computed tomography of human brain tumors: Quantitative assessment of cerebral blood flow, cerebral blood volume, time-to-peak and microvascular permeability: Report of four cases

Clinical Neurophysiology ◽

10.1016/j.clinph.2008.04.175 ◽

2008 ◽

Vol 119 (9) ◽

pp. e138

Author(s):

J. Bouza Domínguez ◽

K. Rodríguez Gutiérrez ◽

Z. Aparicio Arias ◽

J.A. Jordán González ◽

E. Fermín ◽

...

Keyword(s):

Computed Tomography ◽

Blood Flow ◽

Cerebral Blood Flow ◽

Brain Tumors ◽

Human Brain ◽

Blood Volume ◽

Quantitative Assessment ◽

Cerebral Blood Volume ◽

Perfusion Computed Tomography ◽

Time To Peak

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Effects of graded hypotension on cerebral blood flow, blood volume, and mean transit time in dogs

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1992.262.6.h1908 ◽

1992 ◽

Vol 262 (6) ◽

pp. H1908-H1914 ◽

Cited By ~ 2

Author(s):

M. Ferrari ◽

D. A. Wilson ◽

D. F. Hanley ◽

R. J. Traystman

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Cerebral Perfusion Pressure ◽

Blood Volume ◽

Transit Time ◽

Cerebral Perfusion ◽

Pressure Range ◽

Cerebral Blood Volume ◽

Perfusion Pressure ◽

Mean Transit Time

This study tested the hypothesis that cerebral blood flow (CBF) is maintained by vasodilation, which manifests itself as a progressive increase in mean transit time (MTT) and cerebral blood volume (CBV) when cerebral perfusion pressure is reduced. Cerebral perfusion pressure was decreased in 10 pentobarbital-anesthetized dogs by controlled hemorrhage. Microsphere-determined CBF was autoregulated in all tested cerebral regions over the 40- to 130-mmHg cerebral perfusion pressure range but decreased by 50% at approximately 30 mmHg. MTT and CBV progressively and proportionately increased in the right parietal cerebral cortex over the 40- to 130-mmHg cerebral perfusion pressure range. Total hemoglobin content (Hb1), measured in the same area by an optical method, increased in parallel with the increases in CBV computed as the (CBF.MTT) product. At 30 mmHg cerebral perfusion pressure, CBV and Hb were still increased and MTT was disproportionately lengthened (690% of control). We conclude that within the autoregulatory range, CBF constancy is maintained by both increased CBV and MTT. Outside the autoregulatory range, substantial prolongation of the MTT occurs. When CBV is maximal, further reductions in cerebral perfusion pressure produce disproportionate increases in MTT that signal the loss of cerebral vascular dilatory hemodynamic reserve.

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