Objective
The present study aimed at establishing a new protocol using both ^99mTc-Tetrofosmin (TF) and ¹²³I-BMIPP SPECT to detect myocardial damage within one hour.
Methods
Initial ¹²³I-BMIPP SPECT was immediately followed by ^99mTc-TF SPECT. The influence of ¹²³I scattered rays on ^99mTc energy windows set at 15% and 10% were measured using an RH-2 phantom. Participants in the study were patients with heart diseases who had provided written informed consent to undergo the new protocol. The patients maintained the MONZEN position throughout the procedure and an injection syringe was attached to the left arm for ^99mTc-TF injection during¹²³I-BMIPP SPECT.
Results & Discussion
The phantom study showed only slight ¹²³I contamination of ^99mTc at the 10% window setting. The new method separated the ¹²³I and ^99mTc energy windows well and neither crosstalk nor scatter correction were needed. Images obtained from dual (simultaneous) acquisition were contaminated, whereas contamination and influence of scattered rays were absent in images obtained by use of the new protocol. These images were thus useful for clinical diagnosis.
Conclusion
The new protocol is more convenient for patients and might improve the efficiency of detecting myocardial damage.

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The postal dose audit using radio-photoluminescence glass dosimeters was begun in November 2007 in order to improve the quality of radiotherapy in Japan. However, the irradiation conditions are now limited to the reference conditions which are 10×10 cm² field and 10 cm depth. The application of the glass dosimeters to non-reference conditions is strongly desired. This study dealt with the field-size dependence of the glass dosimeter outputs in the 6 MV photon beams of a medical linear accelerator (Varian Clinac21EX). We irradiated glass dosimeters with square field sizes of 5, 7, 10, 13, 16, 20, 23 and 25 cm side lengths at the 10 cm depth of the water equivalent phantom (SSD＝90 cm). The outputs were compared with ionization chamber outputs. The ratio of the glass dosimeter outputs to the absorbed dose to water obtained with the ionization chamber increased approximately 1.5% between 5×5 cm² and 25×25 cm². We have to consider this field-size dependence when we apply the glass dosimeters to non-reference conditions.

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