1.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
;
Breast
;
Coronary Vessels
;
Feasibility Studies
;
Heart
;
Humans
;
Lung
;
Mastectomy, Segmental
;
Prone Position
;
Prospective Studies
;
Radiotherapy
;
Supine Position
;
Unilateral Breast Neoplasms
2.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.
3.Coinfection between influenza and COVID-19 in neonates: A case report
Min Jeong KANG ; Yoonsun YOON ; Bo-Kyung JE ; Yun Kyung KIM ; Won Hee SEO
Allergy, Asthma & Respiratory Disease 2023;11(1):48-52
Coinfection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with other respiratory pathogens may complicate diagnosis and treatment. Since the risk of coinfection with SARS-CoV-2 is expected to increase during the influenza epidemic period, it is necessary to study the clinical course of coinfection. To our knowledge, there have been a few cases of coinfection between SARS-CoV-2 and influenza virus in neonates. Here, we report the clinical course of a neonate who was coinfected with the influenza virus and SARS-CoV-2. A 20-day-old boy born with low birth weight presented with a fever. The patient was confirmed as positive with coronavirus disease 2019 (COVID-19) and influenza B by real-time polymerase chain reaction at admission, whereas his mother was only COVID-19 positive at that time. Initial chest x-ray revealed hyperinflation and increased peribronchial markings at the right lower lung bronchus, but slightly decreased lung sounds without crackle or wheezing at admission. We administered empirical antibiotics for neonatal sepsis and oseltamivir for influenza B. On the chest x-ray follow-up, the findings showed improvement. After discharge, the patient showed a stable general condition. Children ineligible for COVID-19 vaccination who are coinfected with SARS-CoV-2 and the influenza virus are more likely to develop severe symptoms. It is necessary to detect coinfections as some can be treated with antibiotics and antivirals in young infants.
4.Exploration of the interaction between remote ischemic preconditioning and anesthetic-induced preconditioning using sevoflurane in isolated perfused rabbit heart
Seung-Hee YOO ; Sooyoung CHO ; Yoonsun WON ; Jong Wha LEE
The Ewha Medical Journal 2024;47(4):e68-
Objectives:
Remote ischemic preconditioning (rIPC) is a novel technique in which brief episodes of ischemia and reperfusion in one organ confer protection against prolonged ischemia in a distant organ.In contrast, anesthetic-induced preconditioning (APC) utilizes volatile anesthetics to protect multiple organs from ischemia-reperfusion injury. Both methods are easily integrated into various clinical scenarios for cardioprotection. However, it remains unclear whether simultaneous application of these techniques could result in complementary, additive, synergistic, or adverse effects.
Methods:
An adult rabbit heart Langendorff model of global ischemia/reperfusion injury was used to compare the cardioprotective effect of rIPC and APC alone and in combination relative to untreated (control) hearts. The rIPC group underwent four cycles of 5-minute ischemia on the hind limb, each followed by 5 minutes of reperfusion. The APC group received 2.5 vol% sevoflurane for 20 minutes via a face mask, followed by a 20-minute washout period.
Results:
Both in vivo rIPC, induced by four 5-minute cycles of ischemia/reperfusion on the hind limb, and APC, administered as 2.5 vol% sevoflurane via a mask, significantly reduced the size of myocardial infarction following 30 minutes of global ischemia by >50% compared to the untreated control group (rIPC, 12.1±1.7%; APC, 13.5±2.1%; P<0.01 compared to control, 31.3±3.0%). However, no additional protective effect was observed when rIPC and APC were combined (rIPC+APC, 14.4±3.3%).
Conclusion
Although combining rIPC and APC did not provide additional protection, there was no inhibitory effect of one intervention on the other.
5.Exploration of the interaction between remote ischemic preconditioning and anesthetic-induced preconditioning using sevoflurane in isolated perfused rabbit heart
Seung-Hee YOO ; Sooyoung CHO ; Yoonsun WON ; Jong Wha LEE
The Ewha Medical Journal 2024;47(4):e68-
Objectives:
Remote ischemic preconditioning (rIPC) is a novel technique in which brief episodes of ischemia and reperfusion in one organ confer protection against prolonged ischemia in a distant organ.In contrast, anesthetic-induced preconditioning (APC) utilizes volatile anesthetics to protect multiple organs from ischemia-reperfusion injury. Both methods are easily integrated into various clinical scenarios for cardioprotection. However, it remains unclear whether simultaneous application of these techniques could result in complementary, additive, synergistic, or adverse effects.
Methods:
An adult rabbit heart Langendorff model of global ischemia/reperfusion injury was used to compare the cardioprotective effect of rIPC and APC alone and in combination relative to untreated (control) hearts. The rIPC group underwent four cycles of 5-minute ischemia on the hind limb, each followed by 5 minutes of reperfusion. The APC group received 2.5 vol% sevoflurane for 20 minutes via a face mask, followed by a 20-minute washout period.
Results:
Both in vivo rIPC, induced by four 5-minute cycles of ischemia/reperfusion on the hind limb, and APC, administered as 2.5 vol% sevoflurane via a mask, significantly reduced the size of myocardial infarction following 30 minutes of global ischemia by >50% compared to the untreated control group (rIPC, 12.1±1.7%; APC, 13.5±2.1%; P<0.01 compared to control, 31.3±3.0%). However, no additional protective effect was observed when rIPC and APC were combined (rIPC+APC, 14.4±3.3%).
Conclusion
Although combining rIPC and APC did not provide additional protection, there was no inhibitory effect of one intervention on the other.
6.Exploration of the interaction between remote ischemic preconditioning and anesthetic-induced preconditioning using sevoflurane in isolated perfused rabbit heart
Seung-Hee YOO ; Sooyoung CHO ; Yoonsun WON ; Jong Wha LEE
The Ewha Medical Journal 2024;47(4):e68-
Objectives:
Remote ischemic preconditioning (rIPC) is a novel technique in which brief episodes of ischemia and reperfusion in one organ confer protection against prolonged ischemia in a distant organ.In contrast, anesthetic-induced preconditioning (APC) utilizes volatile anesthetics to protect multiple organs from ischemia-reperfusion injury. Both methods are easily integrated into various clinical scenarios for cardioprotection. However, it remains unclear whether simultaneous application of these techniques could result in complementary, additive, synergistic, or adverse effects.
Methods:
An adult rabbit heart Langendorff model of global ischemia/reperfusion injury was used to compare the cardioprotective effect of rIPC and APC alone and in combination relative to untreated (control) hearts. The rIPC group underwent four cycles of 5-minute ischemia on the hind limb, each followed by 5 minutes of reperfusion. The APC group received 2.5 vol% sevoflurane for 20 minutes via a face mask, followed by a 20-minute washout period.
Results:
Both in vivo rIPC, induced by four 5-minute cycles of ischemia/reperfusion on the hind limb, and APC, administered as 2.5 vol% sevoflurane via a mask, significantly reduced the size of myocardial infarction following 30 minutes of global ischemia by >50% compared to the untreated control group (rIPC, 12.1±1.7%; APC, 13.5±2.1%; P<0.01 compared to control, 31.3±3.0%). However, no additional protective effect was observed when rIPC and APC were combined (rIPC+APC, 14.4±3.3%).
Conclusion
Although combining rIPC and APC did not provide additional protection, there was no inhibitory effect of one intervention on the other.
7.Exploration of the interaction between remote ischemic preconditioning and anesthetic-induced preconditioning using sevoflurane in isolated perfused rabbit heart
Seung-Hee YOO ; Sooyoung CHO ; Yoonsun WON ; Jong Wha LEE
The Ewha Medical Journal 2024;47(4):e68-
Objectives:
Remote ischemic preconditioning (rIPC) is a novel technique in which brief episodes of ischemia and reperfusion in one organ confer protection against prolonged ischemia in a distant organ.In contrast, anesthetic-induced preconditioning (APC) utilizes volatile anesthetics to protect multiple organs from ischemia-reperfusion injury. Both methods are easily integrated into various clinical scenarios for cardioprotection. However, it remains unclear whether simultaneous application of these techniques could result in complementary, additive, synergistic, or adverse effects.
Methods:
An adult rabbit heart Langendorff model of global ischemia/reperfusion injury was used to compare the cardioprotective effect of rIPC and APC alone and in combination relative to untreated (control) hearts. The rIPC group underwent four cycles of 5-minute ischemia on the hind limb, each followed by 5 minutes of reperfusion. The APC group received 2.5 vol% sevoflurane for 20 minutes via a face mask, followed by a 20-minute washout period.
Results:
Both in vivo rIPC, induced by four 5-minute cycles of ischemia/reperfusion on the hind limb, and APC, administered as 2.5 vol% sevoflurane via a mask, significantly reduced the size of myocardial infarction following 30 minutes of global ischemia by >50% compared to the untreated control group (rIPC, 12.1±1.7%; APC, 13.5±2.1%; P<0.01 compared to control, 31.3±3.0%). However, no additional protective effect was observed when rIPC and APC were combined (rIPC+APC, 14.4±3.3%).
Conclusion
Although combining rIPC and APC did not provide additional protection, there was no inhibitory effect of one intervention on the other.
8.Exploration of the interaction between remote ischemic preconditioning and anesthetic-induced preconditioning using sevoflurane in isolated perfused rabbit heart
Seung-Hee YOO ; Sooyoung CHO ; Yoonsun WON ; Jong Wha LEE
The Ewha Medical Journal 2024;47(4):e68-
Objectives:
Remote ischemic preconditioning (rIPC) is a novel technique in which brief episodes of ischemia and reperfusion in one organ confer protection against prolonged ischemia in a distant organ.In contrast, anesthetic-induced preconditioning (APC) utilizes volatile anesthetics to protect multiple organs from ischemia-reperfusion injury. Both methods are easily integrated into various clinical scenarios for cardioprotection. However, it remains unclear whether simultaneous application of these techniques could result in complementary, additive, synergistic, or adverse effects.
Methods:
An adult rabbit heart Langendorff model of global ischemia/reperfusion injury was used to compare the cardioprotective effect of rIPC and APC alone and in combination relative to untreated (control) hearts. The rIPC group underwent four cycles of 5-minute ischemia on the hind limb, each followed by 5 minutes of reperfusion. The APC group received 2.5 vol% sevoflurane for 20 minutes via a face mask, followed by a 20-minute washout period.
Results:
Both in vivo rIPC, induced by four 5-minute cycles of ischemia/reperfusion on the hind limb, and APC, administered as 2.5 vol% sevoflurane via a mask, significantly reduced the size of myocardial infarction following 30 minutes of global ischemia by >50% compared to the untreated control group (rIPC, 12.1±1.7%; APC, 13.5±2.1%; P<0.01 compared to control, 31.3±3.0%). However, no additional protective effect was observed when rIPC and APC were combined (rIPC+APC, 14.4±3.3%).
Conclusion
Although combining rIPC and APC did not provide additional protection, there was no inhibitory effect of one intervention on the other.
9.Factors Associated with Re-excision after Breast-Conserving Surgery for Early-Stage Breast Cancer.
Woohyun JUNG ; Eunyoung KANG ; Sun Mi KIM ; Dongwon KIM ; Yoonsun HWANG ; Young SUN ; Cha Kyong YOM ; Sung Won KIM
Journal of Breast Cancer 2012;15(4):412-419
PURPOSE: Re-excisions after breast-conserving surgery (BCS) for breast cancer cause delays in the adjuvant treatment, increased morbidity, and leads to poor aesthetic results. Thus, efforts to reduce the re-excision rate are essential. This study aimed to conclusively determine the re-excision rate and the factors associated with re-excision after BCS. METHODS: We retrospectively reviewed the medical records and pathological reports of 711 cases that underwent BCS for early-stage breast cancer. Univariate and multivariate analyses were performed. RESULTS: Of the 711 cases of BCS, 71 (10.0%) required re-excision. Patients in the re-excision group were younger than those in the no re-excision group. Non-palpable lesions, the presence of non-mass-like enhancement at magnetic resonance imaging, multifocality, the presence of a ductal carcinoma in situ (DCIS) component, and an infiltrative tumor border were also significantly associated with re-excision. Multivariate analysis indicated that younger age, non-palpable lesions, multifocal lesions, and the presence of a DCIS component were factors which were independently associated with re-excision. Tumors located in the lower inner quadrant had a relatively high involved resection margin rate as well as a narrow resection margin width, especially at the superior and medial margins. Lateral margins showed a tendency toward a wider resection margin width. CONCLUSION: At our institution, the rate of re-excision was low despite the lack of an intraoperative frozen section. Patients with non-palpable or multifocal tumors, a DCIS component, or those who were younger than 50 years were more likely to require re-excision after BCS. These factors should be considered when planning surgical management of early-stage breast cancer. Positive resection margin rates and margin widths differed on a directional basis based on tumor location, and these differences were considerable.
Breast
;
Breast Neoplasms
;
Carcinoma, Intraductal, Noninfiltrating
;
Frozen Sections
;
Humans
;
Magnetic Resonance Imaging
;
Mastectomy, Segmental
;
Medical Records
;
Multivariate Analysis
;
Retrospective Studies
10.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