TY - JOUR
T1 - Effect of protective glasses on radiation dose to eye lenses during whole breast irradiation
AU - Nakamura, Tokiko
AU - Suzuki, Shoichi
AU - Kato, Kyoichi
AU - Pongnapang, Napapong
AU - Hayashi, Naoki
AU - Kurokawa, Chie
AU - Kobayashi, Ikuo
AU - Negishi, Toru
AU - Matsunami, Tamaki
N1 - Funding Information:
We gratefully acknowledge the work of the past and present members of our hospital. Following authors were contributed to this study in each work. Tokiko Nakamura: Authorize this study. Shouichi Suzuki: Data acquisition and analysis. Kyoichi Kato: Radioprotective glass designer. Napapong Pongnapang: Data analyze and comments for discussion. Naoki Hayashi: Study design and data analyze. Chie Kurokawa: Data acquisition and comments for discussion. Ikuo Kobayashi: Technical advisor to measure radiation by OSLD. Toru Negishi: Mentor of first author and comments for discussion. Tamaki Matsunami: Data acquisition and operated the machine. Other members in past and present hospitals took cooperating in measurement even though they are excluded.
PY - 2020/11
Y1 - 2020/11
N2 - Objectives: The efficacy of radiotherapy for breast cancer has greatly improved owing to better irradiation methods. Radiotherapy aims to deliver therapeutic doses to predetermined target volumes while sparing surrounding healthy tissues. However, there are few reports on radiation exposure to eye lenses, and the recommended exposure limits to ocular lens have been substantially reduced in recent years. This study aimed to investigate the amount of radiation exposure to eye lenses using optically stimulated luminescence dosimeters (OSLDs) and determine whether wearing special protective devices to protect the eyes, as an organ at risk, during whole breast irradiation, is necessary. Methods: This experiment used OSLDs on water-equivalent phantom to measure the change in scattered radiation dose due to the difference of irradiation field while using 4- and 6-MV photons of TrueBeam linear accelerator. Using a total treatment dose of 50 Gy, a target was positioned to approximate the breast, and a plan was formulated to deliver 2 Gy per treatment by tangential irradiation. The mean (SD) irradiation dose at the lens position outside the irradiation field was reported. Results: The scattered radiation dose outside the irradiation field was more affected by the irradiation field size than by the radiation energy. The out-of-field irradiation dose with a larger field of view was higher than that with a smaller field of view. The use of 0.07- and 0.83-mm-thick lead shield protective glasses reduced the radiation dose by 56.1% (P <.001) and 55.6% (P <.001), respectively. Conclusions: In this experimental model, the amount of radiation the eye was exposed to during whole breast irradiation was determined by the distance of the eye from the radiation field edge and by wearing protective glasses. In clinical practice, the protection offered by eyeglasses may reduce the risk of long-term side effects and allow the use of higher intensive radiotherapy.
AB - Objectives: The efficacy of radiotherapy for breast cancer has greatly improved owing to better irradiation methods. Radiotherapy aims to deliver therapeutic doses to predetermined target volumes while sparing surrounding healthy tissues. However, there are few reports on radiation exposure to eye lenses, and the recommended exposure limits to ocular lens have been substantially reduced in recent years. This study aimed to investigate the amount of radiation exposure to eye lenses using optically stimulated luminescence dosimeters (OSLDs) and determine whether wearing special protective devices to protect the eyes, as an organ at risk, during whole breast irradiation, is necessary. Methods: This experiment used OSLDs on water-equivalent phantom to measure the change in scattered radiation dose due to the difference of irradiation field while using 4- and 6-MV photons of TrueBeam linear accelerator. Using a total treatment dose of 50 Gy, a target was positioned to approximate the breast, and a plan was formulated to deliver 2 Gy per treatment by tangential irradiation. The mean (SD) irradiation dose at the lens position outside the irradiation field was reported. Results: The scattered radiation dose outside the irradiation field was more affected by the irradiation field size than by the radiation energy. The out-of-field irradiation dose with a larger field of view was higher than that with a smaller field of view. The use of 0.07- and 0.83-mm-thick lead shield protective glasses reduced the radiation dose by 56.1% (P <.001) and 55.6% (P <.001), respectively. Conclusions: In this experimental model, the amount of radiation the eye was exposed to during whole breast irradiation was determined by the distance of the eye from the radiation field edge and by wearing protective glasses. In clinical practice, the protection offered by eyeglasses may reduce the risk of long-term side effects and allow the use of higher intensive radiotherapy.
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U2 - 10.1002/acm2.13073
DO - 10.1002/acm2.13073
M3 - Article
AN - SCOPUS:85094671279
VL - 21
SP - 272
EP - 277
JO - Journal of Applied Clinical Medical Physics
JF - Journal of Applied Clinical Medical Physics
SN - 1526-9914
IS - 11
ER -