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The Patlak-plot and conventional methods of determining brain uptake ratio (BUR) have some problems with reproducibility. We formulated a method of determining BUR using anatomic standardization (BUR-AS) in a statistical parametric mapping algorithm to improve reproducibility. The objective of this study was to demonstrate the inter- and intraoperator reproducibility of mean cerebral blood flow as determined using BUR-AS in comparison to the conventional-BUR (BUR-C) and Patlak-plot methods. Methods: The images of 30 patients who underwent brain perfusion SPECT were retrospectively used in this study. The images were reconstructed using ordered-subset expectation maximization and processed using an automatic quantitative analysis for cerebral blood flow of ECD tool. The mean SPECT count was calculated from axial basal ganglia slices of the normal side (slices 31–40) drawn using a 3-dimensional stereotactic region-of-interest template after anatomic standardization. The mean cerebral blood flow was calculated from the mean SPECT count. Reproducibility was evaluated using coefficient of variation and Bland–Altman plotting. Results: For both inter- and intraoperator reproducibility, the BUR-AS method had the lowest coefficient of variation and smallest error range about the Bland–Altman plot. Mean CBF obtained using the BUR-AS method had the highest reproducibility. Conclusion: Compared with the Patlak-plot and BUR-C methods, the BUR-AS method provides greater inter- and intraoperator reproducibility of cerebral blood flow measurement.

(131)I-metaiodobenzylguanidine (MIBG) has been used as a therapeutic agent for pheochromocytoma. Tumor localization and precise staging are essential for therapy with high-dose (131)I-MIBG. The sites and extent of (123)I-MIBG uptake are usually estimated to predict the effectiveness of therapy before administration. However, conventional scintigraphic images provide insufficient anatomic information. Therefore, we tried to manually superimpose (123)I-MIBG SPECT and CT images using free software.

This study was performed to investigate the usefulness of a general-purpose medium-energy (ME) collimator for the accurate localization of the sentinel lymph node (SLN) in breast cancer patients.We compared phantom images and lymphoscintigraphy images obtained under different conditions for a patient with breast cancer. Comparisons were performed between 2 cameras, between a low-energy high-resolution (LEHR) collimator and a general-purpose ME collimator, and between energy windows centered at 141 keV and at 146 keV. Profile curves and image contrast were evaluated along with the visual interpretation of images. The most suitable imaging time was selected from the relationship between contrast and the data acquisition time.The images obtained with the general-purpose ME collimator and the energy window centered at 141 keV were of poorer quality than those obtained with the LEHR collimator and the same energy window. However, the quality of the images obtained with the general-purpose ME collimator improved when the energy window was centered at 146 keV. The method involving the general-purpose ME collimator and the energy window centered at 146 keV showed excellent image quality similar to that obtained with the LEHR collimator. The enhancement of contrast was confirmed at more than 3 cm away from the center of the injection site. Stable contrast was obtained with a data acquisition time of 5 min, with the general-purpose ME collimator, and with the energy window centered at 146 keV.The method involving the general-purpose ME collimator and the energy window centered at 146 keV has the merit of the lymph node not being concealed by a lead shield. This new method is expected to improve the rate of detection of SLN and has the potential for shortening the acquisition time.