ESTIMATION OF ORGAN ABSORBED DOSES IN MICE FROM 99MTC-MIBI USING MYOCARDIAL PERFUSION IMAGING

MONIRA M. RAGEH*#, REEM H. EL-GEBALY*, I. MAAMOUN**
*Department of Biophysics, Faculty of Science, Cairo University, Giza, Egypt
**Intensive Care Unit, Faculty of Medicine, Cairo University, Giza, Egypt

In nuclear medicine, the absorbed dose for target organs in myocardial perfusion imaging (MPI) has a critical role in assessment of radiation risk. Estimation of heart, liver and kidney absorbed doses of 99mTc-MIBI (Technetium sestamibi methoxyisobutyle isonutrile) in mice following myocardial perfusion imaging is important. In this study, the disintegration of administered radionuclides in heart, liver and kidney of mice was estimated. Diagnostic amounts of 99mTc-MIBI were counted by dose calibrator at different time intervals (10 min, 120 min and 240 min). Finally, organs’ activity, residence time and absorbed dose were calculated. The results show that the absorbed doses for heart, liver and kidneys were 1.56, 0.53 and 0.51 mGy respectively and the residence times were 0.0568, 0.158 and 0.0938 h correspondingly. In conclusion, this study may be useful to demonstrate the target organs (heart) in myocardial perfusion imaging compared to other organs and assessment the risk of radiation.
Key words: 99mTc-MIBI, MPI, absorbed dose, heart.

Corresponding author’s e-mail: monirarageh@yahoo.com

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