The 2024 National Diagnostic Reference Levels for Nuclear Medicine Imaging in Korea.

Purpose: The Korean Society of Nuclear Medicine (KSNM) established the first diagnostic reference levels (DRLs) in Korea in 2019. Over the past five years, the need to update the DRLs has emerged for adult nuclear medicine imaging in Korea. The KSNM therefore conducted a nationwide survey and updated the DRLs for adult nuclear medicine examinations. Methods: A national DRL survey was conducted from March 2024 to April 2024 to investigate the administered activities of radiopharmaceuticals and the radiation doses from hybrid CT associated with PET/CT and SPECT/CT. Compared with the 2019 DRLs, the updated DRLs reflect newly approved radiopharmaceuticals in Korea, the introduction of SiPM-based PET/CT scanners, and expanded data on hybrid CT radiation exposure. The DRL survey team performed data collection and cleaning, while the DRL Task Force under the Radiation Safety Committee reviewed the draft. The 2024 DRLs were subsequently approved by the Radiation Safety Committee. Results: The current updated DRLs include 41 nuclear medicine imaging studies and nine hybrid CT studies. For PET radiopharmaceuticals, new DRLs were established for 18F-FDG in the purpose of myocardial viability assessment, infection/inflammation, and screening. Additionally, DRLs for 18F-Florbetaben, 18F-Flutemetamol and 18F-Florapronol for brain amyloid imaging were newly introduced. For SPECT radiopharmaceuticals, new DRLs were established for cardiac scintigraphy using 99mTc-DPD, HDP, or PYP, and for cardiac sympathetic nerve imaging with 123I-MIBG. The DRLs for hybrid CT doses (three PET/CT and six SPECT/CT studies) represent a novel addition in the 2024 nationwide survey. Furthermore, administered doses of radiopharmaceuticals and hybrid CT radiation doses were compared between conventional and SiPM-based PET/CT scanners. Conclusions: The DRLs for nuclear medicine imaging in Korean were updated. The 2024 DRLs will support the optimization of medical exposure to ionizing radiation in nuclear medicine imaging practice in Korea.