Comparison of 133xenon and 123I-isopropylamphetamine for measuring regional cerebral circulation

In 26 patients the regional cerebral blood flow was measured using 123I-isopropyl-amphetamine. The measurement was performed with a dynamic single photon emission tomograph. In 16 patients we compared the findings with the results of the tomographic 133Xe-Clearance. Both methods seem to be suitable for the measurement of the effective perfusion and gave similar results. In the case of the tomographic 133Xe-clearance we need a more specialized technical equipment whereas the permanent costs are lower and the performance less complicated. Besides the applicability of this method is more universal. On the contrary the use of 123I-isopropyl-amphetamine makes a higher resolution possible depending on the available equipment and does not need an ability to cooperation of the patient. With the presently disposable radionuclides the hope was not yet adequately accomplished, to get a tomographic in-vivo-information of cerebral metabolic and receptor-functions by means of SPECT.