Abstract:
Objective To estimate the effective dose of 68Ga-Octreotide PET/CT imaging patients to the surrounding population.
Methods Twenty patients (15 males and 5 females, aged 30–68 (49.0±12.2) years) who received 68Ga-Octreotide PET/CT imaging at Peking University Cancer Hospital from October 2021 to December 2021 were randomly selected. After intravenous injection of 68Ga-Octreotide, the air absorbed dose rate at 1 m away from the patient was measured by radiation monitoring dosimeter 0 h later, at 0.3 m away from the patient 1.0 h later, and at 0.3, 0.5, 1.0, and 1.5 m away from the patient 1.5 h later. Based on the patterns of human social activity proposed by the National Commission for Radiological Protection and Measurement No.155 report, integral method was used to estimate the effective dose of 8Ga-Octreotide PET/CT imaging patients to the surrounding population.
Results Immediately after the injection of 68Ga-Octreotide, the air absorbed dose rate at 1.0 m away from the patient was 12.97–33.67 (20.24±6.57) μSv/h. At 1.0 h later, the air absorbed dose rate at 0.3 m away from the patient was 32.73–57.69(48.98±6.20) μSv/h. At 1.5 h later, the air absorbed dose rates at 0.3, 0.5, 1.0, and 1.5 m away from the patient were 24.04–42.39 (35.98±4.56), 11.83–28.83 (20.70±4.55), 5.17–13.42 (8.07±2.61), and 1.51–7.01 (3.75±1.72) μSv/h, respectively. The estimated effective doses were as follows: 8.22–21.33 (12.83±4.15) μSv to a family member exposed to the patients at the daytime; 38.92–68.62 (58.25±7.38) μSv to a family member who shared a bed at night with the patients; 8.37–21.73 (13.06±4.23) μSv to a colleague; and 32.97–58.15 (49.36±6.26) μSv to an adjacent passenger. The radiation doses per 68Ga-Octreotide PET/CT imaging patients was estimated to be 2.66–4.69 (3.98±0.50) μSv to the operator and 9.70–25.17(15.13±4.90) μSv to the attending nurses.
Conclusion The effective dose of 68Ga Octreotide PET/CT imaging patients to the surrounding population is far lower than the effective dose limit specified in the national standard.