1.The effect of photon energy on intensity-modulated radiation therapy (IMRT) plans for prostate cancer.
Wonmo SUNG ; Jong Min PARK ; Chang Heon CHOI ; Sung Whan HA ; Sung Joon YE
Radiation Oncology Journal 2012;30(1):27-35
PURPOSE: To evaluate the effect of common three photon energies (6-MV, 10-MV, and 15-MV) on intensity-modulated radiation therapy (IMRT) plans to treat prostate cancer patients. MATERIALS AND METHODS: Twenty patients with prostate cancer treated locally to 81.0 Gy were retrospectively studied. 6-MV, 10-MV, and 15-MV IMRT plans for each patient were generated using suitable planning objectives, dose constraints, and 8-field setting. The plans were analyzed in terms of dose-volume histogram for the target coverage, dose conformity, organs at risk (OAR) sparing, and normal tissue integral dose. RESULTS: Regardless of the energies chosen at the plans, the target coverage, conformity, and homogeneity of the plans were similar. However, there was a significant dose increase in rectal wall and femoral heads for 6-MV compared to those for 10-MV and 15-MV. The V20 Gy of rectal wall with 6-MV, 10-MV, and 15-MV were 95.6%, 88.4%, and 89.4% while the mean dose to femoral heads were 31.7, 25.9, and 26.3 Gy, respectively. Integral doses to the normal tissues in higher energy (10-MV and 15-MV) plans were reduced by about 7%. Overall, integral doses in mid and low dose regions in 6-MV plans were increased by up to 13%. CONCLUSION: In this study, 10-MV prostate IMRT plans showed better OAR sparing and less integral doses than the 6-MV. The biological and clinical significance of this finding remains to be determined afterward, considering neutron dose contribution.
Head
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Humans
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Neutrons
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Organs at Risk
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Prostate
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Prostatic Neoplasms
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Retrospective Studies
2.Erratum: Acknowledgments correction.
Wonmo SUNG ; Jong Min PARK ; Chang Heon CHOI ; Sung Whan HA ; Sung Joon YE
Radiation Oncology Journal 2012;30(2):96-96
The funding acknowledgment in this article was omitted as published.
3.Volumetric modulated arc therapy for carotid sparing in the management of early glottic cancer.
Young Suk KIM ; Jaegi LEE ; Jong In PARK ; Wonmo SUNG ; Sol Min LEE ; Gwi Eon KIM
Radiation Oncology Journal 2016;34(1):18-25
PURPOSE: Radiotherapy of the neck is known to cause carotid artery stenosis. We compared the carotid artery dose received between volumetric modulated arc therapy (VMAT) and conventional fixed-field intensity-modulated radiotherapy (IMRT) plans in patients with early glottic cancer. MATERIALS AND METHODS: Twenty-one early glottic cancer patients who previously underwent definitive radiotherapy were selected for this study. For each patient, double arc VMAT, 8-field IMRT, 3-dimensional conformal radiotherapy (3DCRT), and lateral parallel-opposed photon field radiotherapy (LPRT) plans were created. The 3DCRT plan was generated using lateral parallel-opposed photon fields plus an anterior photon field. VMAT and IMRT treatment plan optimization was performed under standardized conditions to obtain adequate target volume coverage and spare the carotid artery. Dose-volume specifications for the VMAT, IMRT, 3DCRT, and LPRT plans were calculated with radiotherapy planning system. Monitor units (MUs) and delivery time were measured to evaluate treatment efficiency. RESULTS: Target volume coverage and homogeneity results were comparable between VMAT and IMRT; however, VMAT was superior to IMRT for carotid artery dose sparing. The mean dose to the carotid arteries in double arc VMAT was reduced by 6.8% compared to fixed-field IMRT (p < 0.001). The MUs for VMAT and IMRT were not significantly different (p = 0.089). VMAT allowed an approximately two-fold reduction in treatment delivery time in comparison to IMRT (3 to 5 minutes vs. 5 to 10 minutes). CONCLUSION: VMAT resulted in a lower carotid artery dose compared to conventional fixed-field IMRT, and maintained good target coverage in patients with early glottic cancer.
Animals
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Carotid Arteries
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Carotid Stenosis
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Glottis
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Humans
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Mice
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Neck
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Radiotherapy
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Radiotherapy, Conformal
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Radiotherapy, Intensity-Modulated*
4.Proper Management of Posttraumatic Tension Pneumocephalus.
Jinwon KWON ; Hyoung Kyun RHA ; Hae Kwan PARK ; Chung Kee CHOUGH ; Won Il JOO ; Sung Hoon CHO ; Wonmo GU ; Wonjun MOON ; Jaesung HAN
Korean Journal of Neurotrauma 2017;13(2):158-161
Pneumocephalus is commonly seen after craniofacial injury. The pathogenesis of pneumocephalus has been debated as to whether it was caused by ball valve effect or combined episodic increased pressure within the nasopharynx on coughing. Discontinuous exchange of air and cerebrospinal fluid due to “inverted bottle” effect is assumed to be the cause of it. Delayed tension pneumocephalus is not common, but it requires an active management in order to prevent serious complication. We represent a clinical case of a 57-year-old male patient who fell down from 3 m height, complicated by tension pneumocephalus on 5 months after trauma. We recommend a surgical intervention, but the patient did not want that so we observe the patient. The patient was underwent seizure and meningitis after 7 months after trauma, he came on emergency room on stupor mentality. Tension pneumocephalus may result in a neurologic disturbance due to continued air entrainment and it significantly the likelihood of intracranial infection caused by continued open channel. Tension pneumocephalus threat a life, so need a neurosurgical emergency surgical intervention.
Cerebrospinal Fluid
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Cerebrospinal Fluid Leak
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Cough
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Craniocerebral Trauma
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Emergencies
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Emergency Service, Hospital
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Humans
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Male
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Meningitis
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Middle Aged
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Nasopharynx
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Pneumocephalus*
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Seizures
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Stupor