title: Volumetric measurements in endotoxic shock using single photon emission tomography (SPET).
abstract: In 25 sheep organ volumes were determined using single photon emission tomography (SPET) prior to and during early endotoxic shock. The tracer used was in vitro 99Tcm-labelled red blood cells. The comparisons between the SPET volumes with the different lower threshold (LT) settings and the 'true' weighed organ volumes were done. The correlation coefficient of -0.87 was found between the LT and the 'true' liver volume and same for the spleen was -0.87. The LT-volume correction curves were used to determine the correct SPET volumes. Thus the accuracy of the liver volume lies within +/- 8%, the splenic volume within +/- 13% and that for the kidney volume +/- 19%. A highly significant decrease of the splenic volume was found 1 h after the induction of endotoxic shock, from 178 +/- 55 ml (mean +/- S.D.) to 101 +/- 25 ml. The kidney volume also decreased from 102 +/- 28 to 78 +/- 19 ml (p less than 0.05), whereas the liver volume remained nearly unchanged (796 +/- 219 versus 761 +/- 165 ml). The SPET study allows measurement of the organ volumes in vivo and the results are reliable when compared to the 'true' volumes. However, the proper LT-settings for organ contour are volume dependent and must be taken into account.
mesh_terms: D000818:Animals; D007668:Kidney / Q000000981:diagnostic imaging* / Q000473:pathology; D008099:Liver / Q000000981:diagnostic imaging* / Q000473:pathology; D012756:Sheep; D012772:Shock, Septic / Q000000981:diagnostic imaging* / Q000473:pathology; D013154:Spleen / Q000000981:diagnostic imaging* / Q000473:pathology; D014055:Tomography, Emission-Computed