To avoid the influence of cross-talk photons, we developed a new scanning method of123I-BMIPP and201TlCl myocardial SPECT named“serial dual isotope SPECT”and estimated the usefulness and accuracy of the cross-talk correction. This imaging method consisted of the two serial SPECT : the routine123I-BMIPP SPECT started at 30 min after the injection of123I-BMIPP and the dual isotope SPECT started sequentially at 10 min after the injection of201TlCl. The second SPECT provided the201TlCl image (71±7 keV) with scattering photons from123I-BMIPP. The real201TlCl image without scattering photons was obtained by subtracting the scattering image of the first SPECT from the201TlCl image with scattering photons. To evaluate the accuracy and the usefulness of this method, we carried out a fundamental experiment using filter papers soaked with the individual radiopharmaceutical and an acrylic phantom as a scattering material with the same process. The result showed that the corrected201TlCl image was almost equal to the real201TlCl image in terms of image counts and image profiles. In the myocardial phantom and the clinical study, the correction images showed good agreements with the real201TlCl images of the patient in count profile, polar map, image-contrast and background level. In the phantom study, less than three pixels (about 1.5cm) differences between the first SPECT and the second SPECT were permitted to generate the reliable corrected201TlCl SPECT. The most important advantage of this method is that the difference of photon scattering in individual patients can be corrected perfectly.
This paper describes software developed for personal computer in order to manage the international controlled materials, Th and U, based on the law and regulations. The software was programmed by using commercially available data base software. The materials are managed so that the amount of each meterial is less than the legal limit. The history concerning receipt, transfer, use, storage, and disposal of the material in each container was recorded, and printed out as a book or a legal report. Tests with dummy data confirmed that the software displayed expected performance.