Quantitative cerebral circulation studies with sodium pertechnetate.

A small general-purpose computer interfaced with a gamma scintillation camera was used to compare the integrated counting rates measured over specific regions of the cerebral cortex from the time of intravenous injection of technetate up to the time of peak radioactivity. The initial slope describing the rate of arrival of the tracer at various regions of the cortex was also measured, and comparisons were made between corresponding regions over each cere-@ bral hemisphere. In 50 persons sensitivity method abstracts of exhibits are reviewed the 20th Annual Meeting. Abstracts of exhibits, large or small, are welcomed from members, nonmembers, and organizations. Exhibits supporting scientific papers are encouraged. View boxes for transilluminated material will be available. Abstract Format: Abstracts must be submitted on a special abstract form for scientific exhibits which is available from the Society of Nuclear Medicine, 21 1 E. 43rd Street, New York, New York 10017. Scientific Exhibit Awards: The Society is pleased to announce the presentation of Gold Medal, Silver Medal, and Bronze Medal awards for outstanding exhibits in each of the following categories: Clinical Nu clear Medicine; Instructional; and Biophysicsand Instrumentation. Judging is based on scientific merit, orig inality, display format, and appearance. Judging on the first full meeting day.