Room: Exhibit Hall | Forum 9
Purpose: Medical staffs like radiological technologists, doctors, and nurses are at an increased risk of exposure to radiation while assisting the patient in a position or monitor contrast medium injection during computed tomography (CT). We evaluate the spatial dose distribution at the time of CT examination for each category using Monte Carlo simulation. From the viewpoint of radiation protection, we will examine the effective position of staffs for each category.
Methods: Particle Heavy Iron Transport cord system (PHITS) was used for Monte Carlo code. A single rotation source data was created by Dump file. ICRP 110 voxel male phantom was used for patient model. The dose distribution in the CT room was simulated when scanning the bed from the head to the pelvic part by shifting the bed 1 cm each.
Results: In head scan, the dose on the head side of the patient was high and in the abdominal scan the dose on the foot side of the patient was high. The point at 0.5 m from the isocenter was higher than the 1 m point by about 7.2 times for the head scan, about 4.7 times for the chest scan and about 4.0 times for the abdomen-pelvic scan.
Conclusion: The dose distribution in the CT room varies for each category. The position and distance with the gantry affect the exposure. The staffs should consider the examination and the positional relationship with the gantry when assisting.