National diagnostic reference levels for nuclear medicine in Qatar

Abstract

Nuclear medicine (NM) started in Qatar in mid 1980s with a one head gamma camera in Hamad General Hospital (HGH). However, Qatar is expanding and now Hamad Medical Corporation (HMC) has two NM departments and one Positron Emission Tomography (PET)/CT Center for Diagnosis and Research with several hybrid single photon emission computed tomography (SPECT)/CT and PET/CT. Furthermore, two new NM departments will be established in Qatar in the coming three years. Therefore, there is a need for optimizing radiation protection in NM imaging and establishing diagnostic reference levels (DRLs) for the first time in Qatar. This need, is not only for the NM part of the examination but also for the computed tomography (CT) part especially in hybrid SPECT/CT and PET/CT. Methods: Data was collected for adult patients from the 3 SPECT/CT machines in the two NM facilities and from the 2 PET/CT machines in the PET/CT Center. The 75th percentile values (also known as the third quartile Q3) were considered as preliminary DRL values and they were consistent with the most commonly administered activities. DRL results for NM imaging in Qatar adults are described including various general NM protocols especially Technetium-99m (^99mTc) based radiopharmaceuticals and PET/CT protocols including mainly oncology applications. Results: First DRLs for NM imaging in Qatar adults were established; values are in agreement with other published DRLs as it is the case for example for PET Oncology using ¹⁸F- fluorodeoxyglucose (FDG) with DRLs of 258, 230, 370, 400 and 461–710 MBq for Qatar, Kuwait, Korea, UK and USA, respectively. Similarly, for NM Cardiac Stress or Rest Myocardial Perfusion imaging using^99mTc Methoxy Isobutyl Isonitrile (MIBI), DRLs were 926, 976, 1110, 800 and 945-1402 MBq for Qatar, Kuwait, Korea, UK and USA, respectively. Conclusion: This study will enable administrated activity optimization for NM procedures in Qatar and this will be of great value especially for the new departments that will adhere to these DRLs.