99Tcm-AnnexinⅤScintigraphy of Inferior Vena Cava Thrombus in Rabbits / 中国医学影像学杂志

ABSTRACT

Purpose To explore the features of 99Tcm-AnnexinⅤscintigraphy of venous thrombus and its feasibility of discriminating fresh venous thrombus from old one. Materials and Methods The rabbits (n=15) were randomly divided into three groups (fresh thrombus group, old thrombus group and control group). The inferior vena cava thrombus models were developed in the rabbits of thrombus groups by inserting screw cooper wire into inferior vena cava. The rabbits of control group received sham operation. 99Tcm-AnnexinⅤwas injected in the rabbits of fresh thrombus group and control group one day after operation;the same was done in the rabbits of old thrombus group 14 days after operation. Planar anterior abdominal images were obtained at 30, 60, 90 and 120 min after 99Tcm-AnnexinⅤinjection in all groups respectively. The ratios of thrombus to background of the two thrombus groups and the ratios of the area correspondent to the thrombus groups to background of the control group were calculated by ROIs counts. Then rabbits were executed, and thrombus was used for pathology examination. Results 99Tcm-AnnexinⅤuptake in thrombi was clearly visualized in all rabbits of the fresh thrombus group;whilst negative images showed in all rabbits of the old thrombus group and control group. The thrombus to background ratios of the fresh thrombus group (4.06±0.49) were higher than that of the old thrombus group (2.46±0.38), and also higher than the inferior vena cava below inferior pole of right kidney level to background ratios (2.27±0.24) of the control group (t=5.746, 7.318;P<0.05). All the thrombi of the fresh thrombus group were confirmed as fresh mixed thrombi by HE staining, and those of the old thrombus group were confirmed as old mixed organized thrombi. Conclusion 99Tcm-AnnexinⅤmay become a new acute venous thrombus imaging tracer used to discriminate fresh venous thrombus from old one.