Cerebral blood volume

Hamberg LM, Hunter GJ, Kierstead D, Lo EH, Gilberto Gonzalez R, Wolf GL. Measurement of cerebral blood volume with subtraction three-dimensional functional CT. Am J Neuroradiol 1996 17 1861-1869. 

Sorensen AG, Copen WA, 0stergaard L, Buonanno FS, Gonzalez RG, Rordorf G, Rosen BR, Schwamm LH, Weisskoff RM, Koroshetz WJ. Hyperacute stroke simultaneous measurement of relative cerebral blood volume, relative cerebral blood flow, and mean tissue transit time. Radiology 1999 210 519-527. 

Grubb RL, Jr., Phelps ME, Ter-Pogossian MM. Regional cerebral blood volume in humans. X-ray fluorescence studies. Arch Neurol 1973 28 38-44. 

Sakai F, Nakazawa K, Tazaki Y, Ishii K, Hino H, Igarashi H, Kanda T. Regional cerebral blood volume and hematocrit measured in normal human volunteers hy single-photon emission computed tomography. J Cereb Blood Flow Metab 1985 5 207-213. 

Donahue KM, Krouwer HG, Rand SD, Pathak AP, Marszalkowski CS, Censky SC, Pros RW. Utility of simultaneously acquired gradient-echo and spin-echo cerebral blood volume and morphology maps in brain tumor patients. Magn Reson Med 2000 43 845-853. 

Hunter GJ, Silvennoinen HM, Hamberg LM, Koroshetz WJ, Buonanno FS, Schwamm LH, Rordorf GA, Gonzalez RG. Whole-brain CT perfusion measurement of perfused cerebral blood volume in acute ischemic stroke probability curve for regional infarction. 

A molecule is commonly deemed brain penetrant if its brain-to-plasma concentration ratio (Cb Cp) is >0.04 using nonperfused brain tissue, as cerebral blood volume approximates 4% of total brain volume [6]. Though this ratio determines technically if a compound enters brain tissue, it is treacherous in early discovery to use this single parameter to select one brain-penetrant compound over another as this value alone by... 

Contrast-enhanced MRI with Gd-DTPA has been applied to the evaluation of several compounds in man, some focusing on the hemodynamic effects of the drugs on cerebral blood volumes. Kolbtisch and others compared the anesthetic agents nitrous oxide and sevofhirane, noting them to produce compound-specific patterns of diffuse increases in cerebral blood volume (Kolbitsch et al., 2001). Intravenous cocaine, on the other hand, was observed to produce dose-dependent vasoconstriction of cerebral blood vessels (Kaufman et ul., 1998). 

Kaufman, M.J., Levin. J.M., Maas, L.C., et. al. Cocaine decreases relative cerebral blood volume in humans a dynamic susceptibility contrast magnetic resonance imaging study. Psychopharmacology 138(1), 76-81, 1998. 

Kolbitsch. C., Lorenz, LH., Hoermann, C., et al. Sevoflurane and nitrons oxide increase regional blood-flow (rCBF) and regional cerebral blood volume (rCBV) in a drug-specific manner in human volunteers. Alagn. Resort. Imag. 19,1253 1260, 2001. 

Inhaled anesthetics decrease the metabolic rate of the brain. Nevertheless, the more soluble volatile agents increase cerebral blood flow because they decrease cerebral vascular resistance. The increase in cerebral blood flow is clinically undesirable in patients who have increased intracranial pressure because of a brain tumor or head injury. Volatile anesthetic-induced increases in cerebral blood flow increase cerebral blood volume and further increase intracranial pressure. 

Neuroimaging technique for measuring cerebral blood flow, cerebral blood volume, metabolic rate, oxygen utilization and the oxygen extraction volume. 

Van Lookeren Campagne M, Thomas GR, Thibodeaux H, Palmer JT, Williams SP, Lowe DG, van Bruggen N (1999) Secondary reduction in the apparent diffusion coefficient of water, increase in cerebral blood volume, and delayed neuronal death after middle cerebral artery occlusion and early reperfusion in the rat. J Cereb Blood Flow Metab 19 1354-1364... 

Indicator-dilution theory (Axel 1980 Rosen et al. 1989) leads to the formula for calculation of the relative regional cerebral blood volume (rrCBV)... 

Brain perfusion refers to the microcirculation of the brain (see Chap. 6). Microcirculation comprises the blood circulation in capillary networks and the exchange of oxygen and nutrients between the blood and the brain tissue. The effectiveness of brain perfusion depends on blood pressure, blood velocity, characteristics of the capillary network, capillary wall permeability, and diffusion rates of oxygen and nutrients. In the healthy brain, perfusion is symmetrical, and is substantially higher in the CM than in the WM. It has been approximated that the CBF is about 80 ml/100 g/min in the CM, and 20 ml/100 g/ min in the WM. Brain perfusion is usually quantified in terms of ml/100 g (cerebral blood volume,... 

The longer the neurological deficit lasts and the later in the course of the stroke symptoms CT or DWI are performed, the higher the likelihood of a positive finding. Moderate decreases of cerebral perfusion as defined by increased relative mean transit times (rMTT), decreased relative cerebral blood flow (rCBF) but normal relative cerebral blood volume (rCBV) are typically found in DWI negative TIA or stroke patients (Ay et al. 1999b). 

It follows from the above that the ratio of cerebral blood flow to cerebral blood volume is a measure of cerebral perfusion reserve (Schumann et al. 1998). Below a ratio of approximately 6.0, even if cerebral blood flow is still normal, vasodilatation and cerebral blood volume are maximal and the reserve is exhausted, as shown by a rising oxygen extraction fraction on PET. 

Schumann P, Touzani O, Young AR et al. (1998). Evaluation of the ratio of cerebral blood flow to cerebral blood volume as an index of local cerebral perfusion pressure. Brain 121 1369-1379... 

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