Akihisa Akamune

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Cerebral blood flow (CBF) has been quantified non-invasively using the brain perfusion index (BPI) determined from radionuclide angiographic data generated by technetium-99m hexamethylpropylene amine oxime(99mTc-HMPAO) or technetium-99m ethyl cysteinate dimer(99mTc-ECD). The BPI is generally calculated using graphical analysis (GA). In the present study,(More)
We have proposed a modified early method, which can shorten the total time required for the quantitative regional cerebral blood flow (rCBF) measurement with N-isopropyl-p(-)[123I]iodoamphetamine (123I-IMP) using single-head rotating gamma-camera and the continuous arterial sampling method. Between 7 to 25 minutes after the intravenous injection of(More)
We previously developed an alternative method for estimating the brain perfusion index (BPI) using technetium-99m compounds and spectral analysis (SA) for quantification of cerebral blood flow (CBF). In this study, we investigated the reproducibility of the BPI values obtained by SA (BPIS) using a double injection of technetium-99m ethyl cysteinate dimer(More)
OBJECTIVE This study was designed to determine whether gamma cameras can be substituted for well-type scintillation counters in measuring blood radioactivity counts to be used as an input function for the quantitative measurement of cerebral blood flow (CBF). METHODS Twelve different aqueous 123I solutions were prepared by serial dilution of the original(More)
We devised a method which allowed the triple energy window (TEW) method to be applied for Compton-scatter correction in conventional single photon emission computed tomography (SPECT) systems without any hardware for TEW acquisition. In this method, the data within two subwindows located at both sides of the main window were acquired together. The(More)
We have developed a new method to replace the conventional method of quantitatively measuring cerebral blood flow (CBF), in which octanol-extracted radioactivity counts are measured in continuous arterial blood samples. With the new method, the whole-brain time-activity curves early after the intravenous injection of N-isopropyl-p-[123I]iodoamphetamine were(More)
The present study was designed to investigate a possibility of substitution of the venous blood radioactivity counts sampled 26 min post injection for the octanol-extracted arterial blood radioactivity counts obtained at 5 min after the injection of N-isopropyl-p-[123I]iodoamphetamine (123I-IMP). Furthermore, we investigated whether the integral of input(More)
Studies on application of diethylenetriamine-pentaacetic acid (DTPA) to decrease the non-specific localization of 111In-labeled antibodies (111In-MoAb) to the liver were performed. The transchelation of 111In to the molecule of M.W. 70,000-90,000 by the incubation of 111In-MoAb in human serum was inhibited by adding DTPA. These in vitro findings were also(More)
We developed a new microsphere method using 123I-IMP in which arterial blood is collected at one time point early after 123I-IMP injection instead of conventional continuous arterial blood sampling, and the input count is estimated using a whole brain time-activity curve until that time point. The differential curve dCb(t)/dt of the brain time-activity(More)
From May 1978 to December 1989, 54 patients with pancreatic carcinoma underwent electron beam intraoperative radiotherapy (IORT). Three died of preoperative complications within a month. In 19 patients, liver metastasis and/or peritoneal dissemination became obvious at laparotomy. They therefore underwent IORT with palliative intent. Relief of pain was(More)