Aim of the study was to determine the time needed for establishing maximal labelled red blood cell concentration in hemangioma by scintigraphic semiquantitative blood pool estimation as a function of time.
Patients and methods: Eleven patients (eight females and three males) with total number of fourteen liver hemangiomas have been examined. Nine of them had solitary lesions and remaininig two patients had two and three liver hemangiomas, respectively. All patients underwent blood pool scintigraphy 40, 60, 120 and 180 minutes after in vivo labelling of autologous red blood cells using 740 MBq of 99mTc. After correction for radioactive decay of 99mTc and back-ground correction blood pool indexes, as hemangioma/heart and liver/heart counting rate ratios, have been calculated.
Results: Mean blood pool indexes obtained 40-180 minutes after in vivo red blood cell labelling did not differ significantly (p > 0.05) neither in hemangioma (0.84-0.86) nor in liver tissue (0.55-0.58). In every acquisition time hemangioma blood pool index was substantialy higher than that of liver tissue (p < 0.01).
Conclusion: The results of the study indicates that labelled red blood cells concentration reaches its plateau before 40th minute following in vivo labelling. The concentration difference between hemangioma and liver tissue also does not differ significantly after 40th minute of blood pool examination. In most patients blood pool scintigrams taken 60, 120 and 180 minutes following in vivo RBC labelling do not contribute to diagnostic value of the method.