The diagnostic usefulness of thrombus imaging scintigraphy for blood coagulopathy in the patients with aortic aneurysm

Eighteen patients with aortic aneurysm were studied to identify intraluminal thrombi using 111In-oxine labelled platelet and sup(99m)Tc-fibrinogen scintigraphy. Reliability in the detection of thrombi with 111In-oxine labelled platelet scintigraphy was higher than that with sup(99m)Tc-fibrinogen scintigraphy (94.1% vs 76.9%, respectively). Measurement of mean platelet survival time with 111In-oxine labelled autologous platelets were carried out in eight patients. Seven of them showed focal accumulation of the labelled platelets at the site of aortic aneurysm and mean platelet survival time (6.64 + 1.46 days) was shorter than normal. In the case of abdominal aneurysm, thrombocytopenia was present, his mean platelet survival time was 4.01 days and RI was accumulated at the site of aneurysm. So we could explain his hematological pathophysiology as consumption coagulopathy in the abdominal aneurysm. Using scanning electron-microscopy, we found entrapped platelet with fine fibrin network. That was a favourable coincidence indicating platelet consumption at the site of intraluminal thrombi. We concluded that these immaging techniques using radioisotopes were very useful not only for detecting intraluminal thrombi but for diagnosing consumption coagulopathy and disseminated intravascular coagulation even in the case of without clinical manifestation. (author)