[Dynamic local cerebral circulation study in patients with cerebral diseases--using 99mTc-HSA-D mainly compared with...

We have been using 99mTc-RBC and 99mTc-HSA for cerebral angiography and measurement of the local cerebral blood volume (LCBV) and cerebral/peripheral hematocrit ratio (alpha). 99mTc-HSA, however, has a problem of poor stability in the blood. We conducted basic and clinical studies on 99mTc-HSA-D, a ready-to-use preparation with good stability in the blood. We measured the regional cerebral circulation dynamics in patients with cerebral diseases in comparison with 99mTc-RBC and 99mTc-HSA. 99mTc-HSA-D and 99mTc-RBC showed more than a 90% retention ratio in the blood 60 min after administration, and good SPECT images were obtained using these two pharmaceuticals. On the contrary, 99mTc-HSA was unstable and its retention ratio was 60s% 60 min after administration. 99mTc-HSA does not provide good SPECT images due to free 99mTcO4- which seems to be liberated from 99mTc-HSA in the body, etc. There were no adverse reactions or abnormal laboratory findings caused by the 99mTc-HSA-D administration in any of the patients. Based on these results, it is surmised that 99mTc-HSA-D is clinically useful for measurement of the cerebral blood volume and cerebral/peripheral hematocrit ratio (alpha).