Hosang Jeon

Background/Objectives: Fluoroscopy has been widely adopted in interventional pulmonology, as it facilitates real-time visualization of the bronchoscope, endobronchial ultrasound, and biopsy tools during procedures. The purpose of this study was to evaluate the effectiveness of radiation shields in minimizing scattered X-ray dose to the bronchoscopist in a phantom study and to determine the dose of scattered X-ray dose to medical staff with radiation shields in clinical application. Methods: An anthropomorphic torso phantom was positioned on the fluoroscopic table between the C-arm X-ray tube and the image detector to mimic bronchoscopic operations. Upper and lower body lead shields were used to examine the effectiveness of radiation shielding. Scatter radiation rates were assessed at a first operator location using real-time dosimeters with and without protective devices. In clinical application, the scattered X-ray dose of the first operator and main assistant was measured using wearable radiation dosimeters during 20 procedures. Results: In the phantom study, scattered radiation without shielding was 266.34 ± 8.86 μSv/h (glabella), 483.90 ± 8.01 μSv/h (upper thorax), 143.97 ± 8.20 μSv/h (hypogastrium), and 7.22 ± 0.28 μSv/h (ankle). The combination of upper and lower body lead shields reduced the scattered X-ray dose by 98.7%, 98.3%, 66.2%, and 79.9% at these levels, respectively. In clinical application, mean scattered X-ray dose rates were 0.14 ± 0.05 μSv/procedure (eye), 0.46 ± 0.51 μSv/procedure (chest), 0.67 ± 0.50 μSv/procedure (hypogastrium), and 1.57 ± 2.84 μSv/procedure (assistant’s wrist). Conclusions: The combination of radiation shields significantly reduced the scattered X-ray dose at the operator site in the phantom study. The scattered X-ray dose to medical staff during bronchoscopy can be kept at a low level with the aid of a shielding system.

Hojeong Lee, Dong Woon Kim, Ji Hyeon Joo, Yongkan Ki, Wontaek Kim, Dahl Park, Jiho Nam, Dong Hyeon Kim, Hosang Jeon. Progress in Medical Physics 2024;35:52-7. https://doi.org/10.14316/pmp.2024.35.2.52

전호상, et al. J Korean Fract Soc. 2023 Oct;36(4):111-117. https://doi.org/10.12671/jkfs.2023.36.4.111

Hojeong Lee, Dong Woon Kim, Ji Hyeon Joo, Yongkan Ki, Wontaek Kim , Dahl Park, Jiho Nam, Dong Hyeon Kim, Hosang Jeon. Progress in Medical Physics 2022;33:101-7. https://doi.org/10.14316/pmp.2022.33.4.101

Background/aim This study aimed to compare the dosimetric consequences of respiratory movement in volumetric-modulated arc therapy (VMAT) and three-dimensional conformal radiation therapy (3D-CRT) during postmastectomy radiation therapy, including internal mammary nodes (IMNs). Materials and methods Respiratory motion was implemented to a phantom using a dynamic device. The plans were delivered during cranial-caudal and ventral-dorsal movement in 5-mm (R05) and 10-mm (R10) amplitudes. Results At the IMN, the dose errors were -2.8% (R05) and -6.2% (R10) for 3D-CRT and -4.9% (R05) and -8.5% (R10) for VMAT. The dose errors in chest wall were -.5% (R05) and -6.0% (R10) for 3D-CRT and -1.9% (R05) and -5.3% (R10) for VMAT. The left anterior descending doses showed significantly small absolute values. The gamma pass rates of VMAT were higher than those of 3D-CRT. Conclusions The benefit of VMAT technique in dose distribution was maintained, except in occasional instances of large breathing motion.

김빛별, et al. J Korean Soc Radiol. 2021 Nov;82(6):1477-1492. https://doi.org/10.3348/jksr.2020.0191

Hosang Jeon , Dong Woon Kim , Ji Hyeon Joo , Yongkan Ki , Wontaek Kim , Dahl Park, Jiho Nam , Dong Hyeon Kim. Progress in Medical Physics 2021;32:18-24. https://doi.org/10.14316/pmp.2021.32.1.18