Key Words

blood flow Fluorescent microspheres (FM) have become an attrac-tive alternative to radioactive microspheres (RM) for the measurement of regional blood flow (RBF). The aim of the present study was to investigate the comparability of both methods by measuring RBF with FM and RM. Eight anaesthetised pigs received simultaneous, left atrial in-jections of FM and RM with a diameter of 15 Ìm at six different time points. Blood reference samples were col-lected from the descending aorta. RBF was determined in tissue samples of the myocardium, spleen and kidneys of all 8 animals. After radioactivity of the tissue samples was determined, the samples were processed automati-cally for measuring fluorescence using a recently devel-oped filter device (SPU). RBF was calculated with both the isotope and spectrometric data of both methods for each sample resulting in a total of 10,512 blood flow val-ues. The comparison of the RBF values yielded high linear correlation (mean r2 = 0.95 B 0.03 to 0.97 B 0.02) and excellent agreement (bias 5.4–6.7%, precision 9.9– 16.5%) of both methods. Our results indicate the validity of MS and of the automated tissue processing technique by means of the SPU. Copyright © 2002 S. Karger AG, Base