Skip Navigation
Skip to contents

JYMS : Journal of Yeungnam Medical Science


Author index

Page Path
HOME > Browse Articles > Author index
Ji Woon Yea 3 Articles
Clinical performance of FractionLab in patient-specific quality assurance for intensity-modulated radiotherapy: a retrospective study
Se An Oh, Sung Yeop Kim, Jaehyeon Park, Jae Won Park, Ji Woon Yea
Yeungnam Univ J Med. 2022;39(2):108-115.   Published online September 9, 2021
  • 2,666 View
  • 69 Download
AbstractAbstract PDF
This study was aimed at comparing and analyzing the results of FractionLab (Varian/Mobius Medical System) with those of portal dosimetry that uses an electronic portal imaging device. Portal dosimetry is extensively used for patient-specific quality assurance (QA) in intensity-modulated radiotherapy (IMRT).
The study includes 29 patients who underwent IMRT on a Novalis-Tx linear accelerator (Varian Medical System and BrainLAB) between June 2019 and March 2021. We analyzed the multileaf collimator (MLC) DynaLog files generated after portal dosimetry to evaluate the same condition using FractionLab. The results of the recently launched FractionLab at various gamma indices (0.1%/0.1 mm–1%/1 mm) are analyzed and compared with those of portal dosimetry (3%/3 mm).
The average gamma passing rates of portal dosimetry (3%/3 mm) and FractionLab are 98.1 (95.5%–100%) and 97.5% (92.3%–99.7%) at 0.6%/0.6 mm, respectively. The results of portal dosimetry (3%/3 mm) are statistically comparable with the QA results of FractionLab (0.6%/0.6 mm–0.9%/0.9 mm).
This paper presents the clinical performance of FractionLab by the comparison of the QA results of FractionLab using portal dosimetry with various gamma indexes when performing patient-specific QA in IMRT treatment. Further, the appropriate gamma index when performing patient-specific QA with FractionLab is provided.
Non–coplanar whole brain radiotherapy is an effective modality for parotid sparing
Jaehyeon Park, Jae Won Park, Ji Woon Yea
Yeungnam Univ J Med. 2019;36(1):36-42.   Published online January 3, 2019
  • 6,053 View
  • 120 Download
  • 6 Citations
AbstractAbstract PDF
The purpose of this study was to evaluate the efficacy and feasibility of non–coplanar whole brain radiotherapy (NC–WBRT) for parotid sparing.
Fifteen cases, previously treated with WBRT were selected. NC–WBRT plans were generated. The beam arrangement for the non–coplanar plans consisted of superior anterior, right, and left beams. After generation of the non–coplanar plans a field–in–field technique was applied to the bilateral parallel opposed beams in order to reduce maximum dose and increase dose homogeneity. The NC–WBRT plans were subsequently compared with the previously generated bilateral WBRT (B–WBRT) plans. A field–in–field technique was also used with the B–WBRT plans according to our departmental protocol. As per our institutional practice a total dose of 30 Gy in 10 fractions of WBRT was administered 5 days a week.
The mean dose to the parotid gland for the two different plans were 16.2 Gy with B–WBRT and 13.7 Gy with NC–WBRT (p<0.05). In the NC–WBRT plan, the V5Gy, V10Gy, V15Gy, V20Gy, and V25Gy of the parotid were significantly lower (p<0.05) than those of the B–WBRT plan. The Dmax of the lens was also lower by 10% with NC–WBRT.
The use of NC–WBRT plans could be a simple and effective method to reduce irradiated volumes and improve the dose–volume parameters of the parotid gland.


Citations to this article as recorded by  
  • Retrospective analysis of portal dosimetry pre-treatment quality assurance of intracranial SRS/SRT VMAT treatment plans
    Ernest Osei, Sarah Graves, Johnson Darko
    Journal of Radiotherapy in Practice.2022; 21(4): 540.     CrossRef
  • Application of piecewise VMAT technique to whole-brain radiotherapy with simultaneous integrated boost for multiple metastases
    Yuan Xu, Yingjie Xu, Kuo Men, Jianping Xiao, Jianrong Dai
    Radiation Oncology.2022;[Epub]     CrossRef
  • Setup uncertainties and appropriate setup margins in the head-tilted supine position of whole-brain radiotherapy (WBRT)
    Jae Won Park, Ji Woon Yea, Jaehyeon Park, Se An Oh, Ngie Min Ung
    PLOS ONE.2022; 17(8): e0271077.     CrossRef
  • Examination of the best head tilt angle to reduce the parotid gland dose maintaining a safe level of lens dose in whole‐brain radiotherapy using the four‐field box technique
    Hidetoshi Shimizu, Koji Sasaki, Takahiro Aoyama, Hiroyuki Tachibana, Hiroshi Tanaka, Yutaro Koide, Tohru Iwata, Tomoki Kitagawa, Takeshi Kodaira
    Journal of Applied Clinical Medical Physics.2021; 22(2): 49.     CrossRef
  • Noncoplanar Versus Coplanar Intensity-Modulated Radiation Therapy (IMRT) for Protection of the Lip and Buccal Mucosa
    Zheng Lao, Fan Bi, Wenhui Fan, Xuanli Xu, Wenyong Tu, Huifeng Shi
    Technology in Cancer Research & Treatment.2021; 20: 153303382110195.     CrossRef
  • Whole brain radiotherapy using four-field box technique with tilting baseplate for parotid gland sparing
    Jaehyeon Park, Ji Woon Yea
    Radiation Oncology Journal.2019; 37(1): 22.     CrossRef
The Effects of Nanoparticles for Irradiation.
Ji Woon Yea, Hyun Jin Shin
Yeungnam Univ J Med. 2011;28(2):145-152.   Published online December 31, 2011
  • 1,356 View
  • 4 Download
AbstractAbstract PDF
To evaluate the changes in the radiation dose and temperature distribution on irradiated egg albumin and nanoparticle (Fe3O4) powder mixed egg albumin. METHODS: A new type of phantom was designed by fabricating a 30x30x30cm acryl square inside a 3x3x3cm small square and dividing it into two parts. In the control group, only egg albumin was irradiated, and in the test group, 25nm 20mg/cc, 25nm 40mg/cc, and 1 um 40 mg/cc nanoparticles with egg albumin were irradiated. The radiation isodose distributions and temperature changes were then observed. RESULTS: No significant changes were observed in the radiation dose and temperature distribution. CONCLUSION: The nanoparticles were considered not to have had any effect on the radiation dose and temperature distribution under the experimental conditions. Further studies can be conducted based on the changes in the mixture material.

JYMS : Journal of Yeungnam Medical Science