A New Technique for the Measurement of Cerebral Blood Volume Using 3 μ m Microspheres
Our laboratory has developed a new technique for the measurement of cerebral blood volume (CBV) utilizing 3 μ m radionuclide labeled polystyrene microspheres (RMS). RMS are attractive tracers in view of the variety of gamma emitting labels that are readily available, the simplicity of their application, and the safety afforded by the encasement of the isotope within the spheres. In addition, possible applications of 3 μ m RMS include simultaneous 15 m RMS blood flow determinations and their use with soluble beta emitting isotopes from which they may be physically separated1. Experiments were designed to validate the 3μ m RMS method according to the following criteria: 1) 3 μ m RMS are not extracted by the brain, 2) systemic clearance of 3 μ m RMS is predictable, 3) CBV measurements are similar to those obtained using currently available techniques, 4) the method is sensitive to changes in cerebral blood volume, and 5) the tracer does not alter the animal’s physiologic status.
KeywordsCerebral Blood Volume Systemic Clearance Liquid Nitrogen Freezing Regional Blood Volume Reference Blood Sample
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- 1.DeWitt DS, Rosner MJ, Becker DP, Hayes RL: Measurement of local blood flow and glucose metabolism within the same tissue samples in the feline CNS. Soc Neurosci Abstr 7: 376 (1981).Google Scholar
- 6.Phelps ME, Grubb RL, Ter-Pogossian MM: Correlation between PaCO2 and regional blood volume by x-ray fluorence. J Appl Physiol 35: 274–280 (1973).Google Scholar
- 7.Sklar FH, Burke EF, Langfitt TW: Cerebral blood volume: Values obtained with Cr-labelled red blood cells and RISA. J Appl Physiol: 79–82 (1968).Google Scholar
- 8.Smith AL, Newfeld GR, Uminsky AJ, Wollman H: The effect of arterial CO2 tension on cerebral blood flow, mean transit time, and vascular volume. J Appl Physiol 31: 701–707 (1974).Google Scholar