18FDG positron emission tomography coupled with CT

Fluorine-18 FluoroDesoxyGlucose (18FDG) positron emission tomography (PET/CT) plays an important role in cancer management. Despite the fact that the hybrid camera uses a non-diagnostic scanner, it contributes to additional patient irradiation. The aim was to evaluate the additional effective dose delivered by CT to 18 FDG PET in an adult population who received this examination. This prospective study included 35 patients aged from 19 to 81 years, with a sex ratio of 1.69 F/H. The mean effective dose of the PET part was 4.560 mSv, with extremes ranging from 2.263 to 7.44 mSv. The mean effective dose of the CT was 12.024 mSv, with extremes ranging from 3.996 to 21.744 mSv. The total mean effective dose was 16.586 mSv, with extremes ranging from 7.166 to 26.299 mSv. The percentage of effective dose from CT to total dose from hybrid imaging ranged from 56% to 95%, with a mean of 71.35%. This dose is not negligible. However, taking into account the benefit of hybrid imaging, this additional radiation is justifiable.