1.Bladder filling variations during concurrent chemotherapy and pelvic radiotherapy in rectal cancer patients: early experience of bladder volume assessment using ultrasound scanner.
Jee Suk CHANG ; Hong In YOON ; Hye Jung CHA ; Yoonsun CHUNG ; Yeona CHO ; Ki Chang KEUM ; Woong Sub KOOM
Radiation Oncology Journal 2013;31(1):41-47
PURPOSE: To describe the early experience of analyzing variations and time trends in bladder volume of the rectal cancer patients who received bladder ultrasound scan. MATERIALS AND METHODS: We identified 20 consecutive rectal cancer patients who received whole pelvic radiotherapy (RT) and bladder ultrasound scan between February and April 2012. Before simulation and during the entire course of treatment, patients were scanned with portable automated ultrasonic bladder scanner, 5 times consecutively, and the median value was reported. Then a radiation oncologist contoured the bladder inner wall shown on simulation computed tomography (CT) and calculated its volume. RESULTS: Before simulation, the median bladder volume measured using simulation CT and bladder ultrasound scan was 427 mL (range, 74 to 1,172 mL) and 417 mL (range, 147 to 1,245 mL), respectively. There was strong linear correlation (R = 0.93, p < 0.001) between the two results. During the course of treatment, there were wide variations in the bladder volume and every time, measurements were below the baseline with statistical significance (12/16). At 6 weeks after RT, the median volume was reduced by 59.3% to 175 mL. Compared to the baseline, bladder volume was reduced by 38% or 161 mL on average every week for 6 weeks. CONCLUSION: To our knowledge, this study is the first to prove that there are bladder volume variations and a reduction in bladder volume in rectal cancer patients. Moreover, our results will serve as the basis for implementation of bladder training to patients receiving RT with full bladder.
Humans
;
Observer Variation
;
Rectal Neoplasms
;
Ultrasonics
;
Urinary Bladder
2.Korean First Prospective Phase II Study, Feasibility of Prone Position in Postoperative Whole Breast Radiotherapy: A Dosimetric Comparison
Yoonsun CHUNG ; Jeong Il YU ; Won PARK ; Doo Ho CHOI
Cancer Research and Treatment 2019;51(4):1370-1379
PURPOSE: This first Korean prospective study is to evaluate the feasibility of prone breast radiotherapy after breast conserving surgery for left breast cancer patients who have relatively small breast size and we present dosimetric comparison between prone and supine positions. MATERIALS AND METHODS: Fifty patients underwent two computed tomography (CT) simulations in supine and prone positions. Whole breast, ipsilateral lung, heart, and left-anterior-descending coronary artery were contoured on each simulation CT images. Tangential-fields treatment plan in each position was designed with total 50 Gy in 2-Gy fractions, and then one of the positions was designated for the treatment by comparing target coverage and dose to normal organs. Also, interfractional and intrafractional motion was evaluated using portal images. RESULTS: In total 50 patients, 32 cases were decided as prone-position–beneficial group and 18 cases as supine-position–beneficial group based on dosimetric advantage. Target dose homogeneity was comparable, but target conformity in prone position was closer to optimal than in supine position. For both group, prone position significantly increased lung volume. However, heart volumewas decreased by prone position for prone-position–beneficial group but was comparable between two positions for supine-position–beneficial group. Lung and heart doses were significantly decreased by prone position for prone-position–beneficial group. However, prone position for supine-position–beneficial group increased heart dose while decreasing lung dose. Prone position showed larger interfractional motion but smaller intra-fractional motion than supine position. CONCLUSION: Prone breast radiotherapy could be beneficial to a subset of small breast patients since it substantially spared normal organs while achieving adequate target coverage.
Breast Neoplasms
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Breast
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Coronary Vessels
;
Feasibility Studies
;
Heart
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Humans
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Lung
;
Mastectomy, Segmental
;
Prone Position
;
Prospective Studies
;
Radiotherapy
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Supine Position
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Unilateral Breast Neoplasms
3.Autoimmune Neuropsychiatric Disorder and Tic Symptom Exacerbation in Tourette's Disorder: Comparision of Treatment Modalities.
Yoosook JOUNG ; Yoonsun YANG ; Moonhyang LEE ; Hyo Jung KO ; Youngki CHUNG ; Hoyoung LEE
Journal of Korean Neuropsychiatric Association 2001;40(6):1204-1213
OBJECT: The purpose of this study was to investigate that infection with group A[beta] hemolytic streptococcus may associate the mechanisms that cause or exacerbate some cases of Tourette's disorder and to evaluate the treatment effect of IG therapy, comparing between IG therapy and drug therapy. METHOD: The subjects were divided into three groups composing of the groups with increasing level of ASO titer and the group with normal level of ASO titer, treating with antipsychotics. Children with infection-triggered exacerbation of Tourette's disorder were assigned treatment with IVIG (400mg/kg/daily on 5 consecutive days) or antipsychotic drugs. Symptom severity was rated at baseline, and at 4weeks, at at 8weeks after treatment by use of standard assessment scale of tics. RESULTS: 1) The motor tic score, global severity scores and overall TS impairment rating scores of YGTSS in the group with incresing level of ASO titer were related with ASO titer. 2) Immune therapy was more effective in the group with incresing level of ASO titer than antipsychotic drug therapy. CONCLUSION: These results suggest that increasing level of ASO titer, resulting from group A[beta] hemolytic streptococcal infection has affected worsening the tic symptoms in Touette's disorder and in group with increasing level of ASO titer, IVIG therapy is more effective than drug therapy.
Antipsychotic Agents
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Child
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Drug Therapy
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Humans
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Immunoglobulins, Intravenous
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Streptococcal Infections
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Streptococcus
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Tics*
;
Tourette Syndrome*
4.Magnetic resonance image-based tomotherapy planning for prostate cancer
Sang Hoon JUNG ; Jinsung KIM ; Yoonsun CHUNG ; Bilgin KESERCI ; Hongryull PYO ; Hee Chul PARK ; Won PARK
Radiation Oncology Journal 2020;38(1):52-59
Purpose:
To evaluate and compare the feasibilities of magnetic resonance (MR) image-based planning using synthetic computed tomography (sCT) versus CT (pCT)-based planning in helical tomotherapy for prostate cancer.
Materials and Methods:
A retrospective evaluation was performed in 16 patients with prostate cancer who had been treated with helical tomotherapy. MR images were acquired using a dedicated therapy sequence; sCT images were generated using magnetic resonance for calculating attenuation (MRCAT). The three-dimensional dose distribution according to sCT was recalculated using a previously optimized plan and was compared with the doses calculated using pCT.
Results:
The mean planning target volume doses calculated by sCT and pCT differed by 0.65% ± 1.11% (p = 0.03). Three-dimensional gamma analysis at a 2%/2 mm dose difference/distance to agreement yielded a pass rate of 0.976 (range, 0.658 to 0.986).
Conclusion
The dose distribution results obtained using tomotherapy from MR-only simulations were in good agreement with the dose distribution results from simulation CT, with mean dose differences of less than 1% for target volume and normal organs in patients with prostate cancer.
5.Variation in Practice Patterns of Korean Radiation Oncologists for Spine Metastasis between 2009 and 2014.
Jeong Il YU ; Hee Chul PARK ; Yong Chan AHN ; Yoonsun CHUNG ; Woong Sub KOOM ; Si Yeol SONG
Cancer Research and Treatment 2016;48(3):1102-1109
PURPOSE: The Korean Society of Radiation Oncologists (KOSRO) conducted the Patterns of Care Study (PCS) of radiotherapy (RT) for spine metastases in 2009. The current study was conducted to investigate current practice patterns and compare them with the results of the PCS. MATERIALS AND METHODS: The survey questionnaire was composed of 10 questions regarding general information and seven questions for each of two clinical scenarios. RESULTS: Fifty-four members of the KOSRO answered at least one question on the web-based questionnaire. The yearly number of patients treated who underwent palliative spine RT was greater than 200 in 14 (25.9%), 51 to 100 in 13 (24.1%), and 31 to 50 in 11 respondents (20.4%). Scenario 1 described a patient presenting with cord compressive spine metastasis in multiple bones and liver metastasis from non-small cell lung cancer. Thirty gray (Gy) in 10 fractions was chosen by 35 respondents (64.8%). Scenario 2 described a case of a single spine metastasis without progression after targeted therapy. Thirty Gy in 10 fractions was chosen by 19 respondents (35.2%), and a single fraction or less than four fractions of stereotactic ablative radiotherapy (SABR) were selected by 18 respondents (33.3%). When compared with the 2009 PCS, practice patterns of Korean radiation oncologists had not changed significantly over 5 years, except that SABR emerged as a new treatment modality in the selected population. CONCLUSION: The 2014 PCS demonstrated that multiple fraction RT is still preferred in a considerable proportion of Korean radiation oncologists.
Carcinoma, Non-Small-Cell Lung
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Data Collection
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Humans
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Korea
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Liver
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Neoplasm Metastasis*
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Practice Patterns, Physicians'
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Radiotherapy
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Spine*
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Surveys and Questionnaires
6.Prediction of Target Motion Using Neural Network for 4-dimensional Radiation Therapy.
Sang Kyung LEE ; Yong Nam KIM ; Kyung Ran PARK ; Kyeongkeun JEONG ; Chang Geol LEE ; Ik Jae LEE ; Jinsil SEONG ; Won Hoon CHOI ; Yoonsun CHUNG ; Sung Ho PARK
Korean Journal of Medical Physics 2009;20(3):132-138
Studies on target motion in 4-dimensional radiotherapy are being world-widely conducted to enhance treatment record and protection of normal organs. Prediction of tumor motion might be very useful and/or essential for especially free-breathing system during radiation delivery such as respiratory gating system and tumor tracking system. Neural network is powerful to express a time series with nonlinearity because its prediction algorithm is not governed by statistic formula but finds a rule of data expression. This study intended to assess applicability of neural network method to predict tumor motion in 4-dimensional radiotherapy. Scaled Conjugate Gradient algorithm was employed as a learning algorithm. Considering reparation data for 10 patients, prediction by the neural network algorithms was compared with the measurement by the real-time position management (RPM) system. The results showed that the neural network algorithm has the excellent accuracy of maximum absolute error smaller than 3 mm, except for the cases in which the maximum amplitude of respiration is over the range of respiration used in the learning process of neural network. It indicates the insufficient learning of the neural network for extrapolation. The problem could be solved by acquiring a full range of respiration before learning procedure. Further works are programmed to verify a feasibility of practical application for 4-dimensional treatment system, including prediction performance according to various system latency and irregular patterns of respiration.
Humans
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Learning
;
Respiration
;
Track and Field
7.Prediction of Target Motion Using Neural Network for 4-dimensional Radiation Therapy.
Sang Kyung LEE ; Yong Nam KIM ; Kyung Ran PARK ; Kyeongkeun JEONG ; Chang Geol LEE ; Ik Jae LEE ; Jinsil SEONG ; Won Hoon CHOI ; Yoonsun CHUNG ; Sung Ho PARK
Korean Journal of Medical Physics 2009;20(3):132-138
Studies on target motion in 4-dimensional radiotherapy are being world-widely conducted to enhance treatment record and protection of normal organs. Prediction of tumor motion might be very useful and/or essential for especially free-breathing system during radiation delivery such as respiratory gating system and tumor tracking system. Neural network is powerful to express a time series with nonlinearity because its prediction algorithm is not governed by statistic formula but finds a rule of data expression. This study intended to assess applicability of neural network method to predict tumor motion in 4-dimensional radiotherapy. Scaled Conjugate Gradient algorithm was employed as a learning algorithm. Considering reparation data for 10 patients, prediction by the neural network algorithms was compared with the measurement by the real-time position management (RPM) system. The results showed that the neural network algorithm has the excellent accuracy of maximum absolute error smaller than 3 mm, except for the cases in which the maximum amplitude of respiration is over the range of respiration used in the learning process of neural network. It indicates the insufficient learning of the neural network for extrapolation. The problem could be solved by acquiring a full range of respiration before learning procedure. Further works are programmed to verify a feasibility of practical application for 4-dimensional treatment system, including prediction performance according to various system latency and irregular patterns of respiration.
Humans
;
Learning
;
Respiration
;
Track and Field
8.Radiation Pneumonitis in Breast Cancer Patients Who Received Radiotherapy Using the Partially Wide Tangent Technique after Breast Conserving Surgery.
Yoonsun CHUNG ; Hong In YOON ; Yong Bae KIM ; Seung Kwon AHN ; Ki Chang KEUM ; Chang Ok SUH
Journal of Breast Cancer 2012;15(3):337-343
PURPOSE: We assessed the risk of radiation pneumonitis (RP) in terms of dosimetric parameters in breast cancer patients, who received radiotherapy using the partially wide tangent technique (PWT), following breast conservation surgery (BCS). METHODS: We analyzed the data from 100 breast cancer patients who underwent radiotherapy using PWT. The entire breast, supraclavicular lymph node, and internal mammary lymph node (IMN) were irradiated with 50.4 Gy in 28 fractions. RP was scored on a scale of 0 to 5, based on Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer toxicity criteria. The dosimetric parameters, used in analysis for the ipsilateral lung, were the mean lung dose (MLD), V5 (percentage of lung volume that received a dose of 5 Gy or more)-V50, and normal tissue complication probability (NTCP). RESULTS: Of the 100 patients, three suffered from symptomatic RP (symptom grade > or =2), but were relieved by supportive care. The risk of RP was not correlated with the treatment regimen. RP associated mostly with asymptomatic minimal pulmonary radiologic change or mild dry cough developed more frequently in the group with MLD > or =20.5 Gy or NTCP > or =23% than in the group with MLD <20.5 Gy and NTCP <23% (48.6% vs. 25.4%, p=0.018). CONCLUSION: Dosimetric parameters of MLD and NTCP were correlated with the incidence of RP, but the clinical impact was minimal. We suggest that PWT is a safe technique for the treatment of IMN for BCS patients with low risk of symptomatic RP.
Breast
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Breast Neoplasms
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Cough
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Humans
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Incidence
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Lung
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Lymph Nodes
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Lymphatic Irradiation
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Mastectomy, Segmental
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Radiation Pneumonitis
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Radiotherapy, Conformal
9.Variants in the Gene EBF2 Are Associated with Kawasaki Disease in a Korean Population.
Yoonsun BAE ; Dongjik SHIN ; Jiho NAM ; Hye Rim LEE ; Jun Sung KIM ; Kyu Yeun KIM ; Dong Soo KIM ; Yeun Jun CHUNG
Yonsei Medical Journal 2018;59(4):519-523
PURPOSE: Kawasaki disease (KD) is a mucocutaneous lymph node syndrome. It is mainly seen in young children under the age of five. KD is a multifactorial disorder that includes genetic variants. The present study investigated the association between KD and single nucleotide polymorphisms (SNPs) in the candidate gene early B cell factor 2 (EBF2), which is associated with inflammation markers. MATERIALS AND METHODS: An SNP analysis was performed by whole exon sequencing of the EBF2 gene. Our study comprised a total of 495 subjects (295 KD patients and 200 unrelated normal controls) from a Korean population. Tag SNPs were discovered using the Haploview program. Genotyping of the EBF2 gene was performed with the TaqMan® assay with real-time PCR methods. RESULTS: Polymorphism of rs10866845 showed a significant difference in allele frequency between KD patients and controls (p=0.040). The EBF2 gene polymorphisms were significantly associated with KD on logistic regression analysis. CONCLUSION: EBF2 gene variants can contribute to KD in the Korean population.
Child
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Exons
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Gene Frequency
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Humans
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Inflammation
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Logistic Models
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Mucocutaneous Lymph Node Syndrome*
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Polymorphism, Single Nucleotide
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Real-Time Polymerase Chain Reaction
10.Surface-Modifying Effect of Zwitterionic Polyurethane Oligomers Complexed with Metal Ions on Blood Compatibility
Dong-Heon GA ; Chung-Man LIM ; Yoonsun JANG ; Tae Il SON ; Dong Keun HAN ; Yoon Ki JOUNG
Tissue Engineering and Regenerative Medicine 2022;19(1):35-47
BACKGROUND:
To prevent unsolved problems of medical devices, we hypothesized that combinatorial effects of zwitterionic functional group and anti-bacterial metal ions can reduce effectively the thrombosis and bacterial infection of polymeric biomaterials. In this research, we designed a novel series of zwitterionic polyurethane (zPU) additives to impart anti-thrombotic properties to a polyvinyl chloride (PVC) matrix.
METHODS:
We have synthesized zPUs by combination of various components and zPUs complexed with metal ions. Zwitterion group was prepared by reaction with 1,3-propane sultone and Nmethyldiethanolamine and metal ions were incorporated into sulfobetaine chains via molecular complexation. These zPU additives were characterized using FT-IR, 1H-NMR, elemental analysis, and thermal analysis. The PVC film blended with zPU additives were prepared by utilizing a solvent casting and hot melting process.
RESULTS:
Water contact angle demonstrated that the introduction of zwitterion group has improved hydrophilicity of polyurethanes dramatically. Protein adsorption test resulted in improved anti-fouling effects dependent on additive concentration and decreases in their effects by metal complexation. Platelet adhesion test revealed anti-fouling effects by additive blending but not significant as compared to protein resistance results.
CONCLUSION
With further studies, the synthesized zPUs and zPUs complexed with metal ions are expected to be used as good biomaterials in biomedical fields. Based on our results, we can carefully estimate that the enhanced anti-fouling effect contributed to reduced platelet adhesion.