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C J Bischof

Publications and source records attributed to C J Bischof.

4 recordsLinked to original sources
PubMed1981

Methods for measurement of cerebral blood flow.

Difficulties in measuring total and regional cerebral flow have hindered advances in knowledge concerning the regulation of the cerebral circulation. Now, however, we can accurately measure total and regional cerebral blood flow with the labeled microsphere method. With this method, flow to cerebral and non-cerebral tissues in the head can be completely separated, and by using microspheres labeled with different radionuclides, six measurements can be obtained in each experiment. A disadvantage of the microsphere method is that flow is not monitored continuously. Therefore, transient changes in flow (less than 20 seconds) cannot be measured accurately, and it is difficult to determine the time course of changes in cerebral blood flow in response to a given stimulus. A new method, simultaneous measurements of velocity and diameter in a pial artery, complements the microsphere approach. With this new method, nearly continuous, accurate measurements of cerebral blood flow are obtainable. Now that several methods for measuring cerebral blood flow are available and appear to be valid, knowledge concerning the regulation of cerebral blood flow should advance more rapidly.

Animals↗
PubMedDate not supplied

Modulation transfer function of the EMI CT head scanner.

The two-dimensional modulation transfer function [MTF(vx, vy)] has been determined for the EMI CT head scanner by measuring the point spread function (PSF) in different locations in the field of view. This PSF was obtained by scanning a fine wire supported perpendicular to the tomographic slice. Based on these MTFs, the resolving power of the EMI scanner was found to be 3.1 line pairs/cm. Our results also verify the symmetry of the system response and the uniformity of the system resolution.

Tomography, X-Ray Computed↗