Congress:
EuroSafe Imaging 2020
Keywords:
Performed at one institution, Experimental, Prospective, Dosimetric comparison, Dosimetry, CT, Radioprotection / Radiation dose, Radiographers, Head and neck, Head and Neck
Authors:
T. Oku, T. Masuda, T. Yoshiura, Y. Matsumoto, Y. yamashita, M. yoshida
DOI:
10.26044/esi2020/ESI-09108
Conclusion and recommendations
As we know, optimal protection is needed to reduce radiation exposure. Also, The ICRP at 2011 recommended that the tissue weighting factor in mammary gland should be raised to 0.12 7). Therefore, we will make educational materials for the patient to reduce exposure dose. This result will be useful for exposure dose protection of the patients. If the staff had known of the outside dose of the examination, protection during the positioning of the patient in a CT scan would keep the patient's exposure as low as possible. We have to understand the outside exposure dose in the CT examination.
It is necessary to select the optimal radiation protection to maintain the image quality. And the scattered exposure dose decreased by using the RPS. Our results show that the radiation dose without RPS was significantly higher than with RPS. Many researchers (in the world) have reported that the use of RPS in CT examinations can reduce radiation doses 8) 9)10). We therefore assure that it is necessary to check the outside radiation dose for the patients care.
The radiation dose reduction rate of mammary gland was higher than radiation dose reduction rate of thyroid gland. This is because the energy of outside X-rays decreases as the distance from the scanning site increases, and RPS greatly depends on the X-ray energy. In addition, the closer to the scan site, the more the influence of internal scattering is. Therefore, we believe that the RPS is useful for more outside radiation dose protection.
It is easy to use the RPS during the Head CT examination. The use of RPS in CT scans involves laying the RPS on a bed and then wrapping the RPS around the patient. It will be very easy and clinically useful for the patients care.
Our study however has several limitations. Firstly, this study is a phantom experiment and it has not been verified by patient study. Secondly, our studies were performed on a single CT scanner model from a single manufacturer. The relationship among the tube voltage, bowtie filters, and radiation dose may depend to some degree on the CT scanner specifications that may vary among manufacturers.
In conclusion, we clarified that using an RPS during head CT examination is useful for reducing radiation dose outside the scan range.