• Radiation Oncology Journal
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• v.15 no.3
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• pp.215-224
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• 1997

Purpose : Stereotactic radiosurgery with external beam irradiation successfully obliterates carefully selected intracranial arteriovenous malformation (AVM) . We Present clinical and radiological long term results after treatment with a single high dose irradiation using a linear accelerator. Materials and Methods : Rrom January 1991 to June 1994, fifteen patients with intracranial AVM were treated in our hospital with the stereotactic radiosurgery using a linear accelerator. The radiation was delivered using a 6 MV linear accelerator. The prescribed doses at the isocenter varied from 1800 to 2500cGy (median : 2000cGy) and were given as a sin91e fraction. The radiation doses at the periphery of the lesion typically corresponded to the 80-90% isodose line. In 14 patients, complete clinical and/or radiological follow-up examination were available. Results : Angiography was available in 13 patients with a follow-up Period from 18 months to 27 months. Of 13 patients, the overall complete obliteration rate was 92.3% (12 patients). This incidence did not correlate with lesion size. Seizure, headache and progressive neurologic deficit were complete recovered. One Patient experienced hemorrhage at 2 months after treatment. One patient developed radiation induced brain edema in the white matter surrounding nidus at 16 months after treatment and showed complete resolution of the edema in MR image obtained at 27 months after treatment. After a follow-up period of up to 6 years, no radiation induced severe late complications occurred. Conclusion : We conclude that stereotactic radiosurgery using a linear accelerator is an effective and safe therapy for symptomatic and surgically inaccessible intracranial AVMs and the results compare favorably to the more expensive and elaborate systems that are currently available for stereotactic radiosurgery.

• Progress in Medical Physics
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• v.16 no.2
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• pp.62-69
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• 2005

The purpose of this study has been performed to investigate the possibility of external audit program using thermoluminescence dosimetry for electron beam in korea. The TLD system consists of LiF powder, type TLD-700 read with a PCL 3 reader. In order to determine a calibration coefficient of the TLD system, the reference dosimeters are irradiated to 2 Gy in a $^{60}CO$ beam at the KFDA The irradiation is performed under reference conditions is water phantom using the IAEA standard holder for TLD of electron beam. The energy correction factor is determined for LiF powder irradiated of dose to water 2 Gy in electron beams of 6, 9, 12, 16 and 20 MeV (Varian CL 2100C). The dose is determined according to the IAEA TRS-398 and by measurement with a PTW Roos type plane-parallel chamber. The TLD for each electron energy are positioned in water at reference depth. In this study, to verify of the accuracy of dose determination by the TLD system are performed through a 'blind' TLD irradiation. The results of blind test are $2.98\%,\;3.39\%\;and\;0.01\%(1\sigma)$ at 9, 16, 20 MeV, respectively. The value generally agrees within the acceptance level of $5\%$ for electron beam. The results of this study prove the possibility of the TLD quality assurance program for electron beams. It has contributed to the improvement of clinical electron dosimetry in radiotherapy centers.

• Radiation Oncology Journal
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• v.22 no.2
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• pp.124-129
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• 2004

Purpose : To evaluate the clinical findings, prognosis and treatment strategy of patients with neuroendocrine carcinoma of cervix. Materials and Methods: Thirteen patients with neuroendocrine carcinoma of cervix were included in this study, as confirmed histologically and immunohistochemically at the Dongsan Medical Center, Keimyung University, between May 1944 and October 2001. The mean age of patients was 56 years with a range of 32 to 78 years of age. According to the FIGO staging system, there were 5 patients with stage IB carcinoma, 5 patients with IIA, and 3 patients with stage IIB. Four patients underwent radical hysterectomy with pelvic lymphadenectomy, 3 of these patients also received postoperative radiotherapy, and one patient underwent extrafascial hysterectomy after radiotherapy. Primary radiotherapy was done in 9 patients, and 3 were irradiated postoperatively. Nine patients received chemotherapy, 7 received neoadjuvant and 2 received concurrent chemoradiotherapy. The radical purpose of radiotherapy consisted of external irradiation to the whole pelvis (4,500 $\~$5,400 cGy) and intracavitary irradiation (3,000 $\~$ 3,500 cGy). Results : The mean follow up duration was 36 months with a range of 3 to 104 months. The overall 5-year survival rate was 61.5$\%$ and the 5-year survival rates for stage IB, IIA, IIB were 60.0$\%$, 60.0$\%$, and 66.7$\%$ respectively (p=0.99). Eight patients are still alive without disease, and all of the 5 patients with recurrence are dead due to distant metastasis. Conclusion : Neuroendocrine carcinoma of cervix is highly aggressive, with early lymphatic dissemination and a high rate of distant recurrence. Therefore, an aggressive therapeutic strategy Is required to obtain pelvic and distant disease control. Multimodal therapy should be considered at the time of Initial diagnosis.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.5
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• pp.339-342
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• 2005

In long-period fiber grating (LPFG) to be made up optical fiber sensors, resonance coupling occurs between the forward-propagating core mode and cladding modes at the wavelength that satisfy the Phase matching condition. The resonance wavelength and the coupling strength depends strongly on the external environment like temperature, strain, and ambient index. These characteristics can be utilized for various applications as optical fiber sensors. fabrication of optical fiber gratings is typically based on the photosensitivity effect, i.e. the permanent change of the refractive index upon irradiation of the UV beam, and therefore, fabrication of the optical fiber with high phososensitivity is an important part of the research on optical fiber gratings. In this work, we measured the effort of to-doping of boron on the index difference between the core and cladding of the optical fiber and the sensitivity of the LPFC to the temperature and bending changes. We observed that the index difference between the core and the cladding decreased by $(1.69{\times}10^{-4}/SCCM)$ and the temperature sensitivity of the resonance wavelength shirt decreased by $(0.01145nm/^{\circ}C/SCCM)$. The dependence or the bending-induced changes or the transmission characteristics of LPFG on the tore-cladding index difference was investigated experimentally. The measurement results indicate that the bending sensitivity increases as the index difference decreases.

• Radiation Oncology Journal
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• v.29 no.3
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• pp.156-163
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• 2011

Purpose: To evaluate long-term local control rate and toxicity in patients treated with external beam radiotherapy (EBRT) for pituitary adenomas. Materials and Methods: We retrospectively reviewed the medical records of 60 patients treated with EBRT for pituitary adenoma at Korea University Medical Center from 1996 and 2006. Thirty-five patients had hormone secreting tumors, 25 patients had non-secreting tumors. Fifty-seven patients had received postoperative radiotherapy (RT), and 3 had received RT alone. Median total dose was 54 Gy (range, 36 to 61.2 Gy). The definition of tumor progression were as follows: evidence of tumor progression on computed tomography or magnetic resonance imaging, worsening of clinical sign requiring additional operation or others, rising serum hormone level against a previously stable or falling value, and failure of controlling serum hormone level so that the hormone level had been far from optimal range until last follow-up. Age, sex, hormone secretion, tumor extension, tumor size, and radiation dose were analyzed for prognostic significance in tumor control. Results: Median follow-up was 5.7 years (range, 2 to 14.4 years). The 10-year actuarial local control rates for non-secreting and secreting adenomas were 96% and 66%, respectively. In univariate analysis, hormone secretion was significant prognostic factor (p = 0.042) and cavernous sinus extension was marginally significant factor (p = 0.054) for adverse local control. All other factors were not significant. In multivariate analysis, hormone secretion and gender were significant. Fifty-three patients had mass-effect symptoms (headache, dizziness, visual disturbance, hypopituitarism, loss of consciousness, and cranial nerve palsy). A total of 17 of 23 patients with headache and 27 of 34 patients with visual impairment were improved. Twenty-seven patients experienced symptoms of endocrine hypersecretion (galactorrhea, amenorrhea, irregular menstruation, decreased libido, gynecomastia, acromegaly, and Cushing's disease). Amenorrhea was abated in 7 of 10 patients, galactorrhea in 8 of 8 patients, acromegaly in 7 of 11 patients, Cushing's disease in 4 of 4 patients. Long-term complication was observed in 4 patients; 3 patients with cerebrovascular accident, 1 patient developed dementia. Of these patients, 3 of 4 received more than 60 Gy of irradiation. Conclusion: EBRT is highly effective in preventing recurrence and reducing mass effect of non-secreting adenoma. Effort to improve tumor control of secreting adenoma is required. Careful long-term follow-up is required when relatively high dose is applied. Modern radiosurgery or proton RT may be options to decrease late complications.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.14
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• pp.5957-5961
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• 2015

Background: We designed this randomized controlled trial (RCT) to assess whether lobaplatin-based concurrent chemotherapy might be superior to cisplatin-based concurrent chemotherapy for FIGO stage II and III cervical cancer in terms of efficacy and safety. Materials and Methods: This prospective, open-label RCT aims to enroll 180 patients with FIGO stage II and III cervical cancer, randomly allocated to one of the three treatment groups (cisplatin $15mg/m^2$, cisplatin $20mg/m^2$ and lobaplatin $35mg/m^2$), with 60 patients in each group. All patients will receive external beam irradiation (EBRT) and high-dose-rate intracavitary brachytherapy (HDR-ICBT). Patients in cisplatin $15mg/m^2$ and $20mg/m^2$ groups will be administered four cycles of $15mg/m^2$ or $20mg/m^2$ cisplatin intravenously once weekly from the second week to the fifth week during EBRT, while patients inthe lobaplatin $35mg/m^2$ group will be administered two cycles of $35mg/m^2$ lobaplatin intravenously in the second and fifth week respectively during pelvic EBRT. All participants will be followed up for at least 12 months. Complete remission rate and progression-free survival (PFS) will be the primary endpoints. Overall survival (OS), incidence of adverse events (AEs), and quality of life will be the secondary endpoints. Results: Between March 2013 and March 2014, a total of 61 patients with FIGO stage II and III cervical cancer were randomly assigned to cisplatin $15mg/m^2$ group (n=21), cisplatin $20mg/m^2$ group (n=21) and lobaplatin $35mg/m^2$ group (n=19). We conducted a preliminary analysis of the results. Similar rates of complete remission and grades 3-4 gastrointestinal reactions were observed for the three treatment groups (P=0.801 and 0.793, respectively). Grade 3-4 hematologic toxicity was more frequent in the lobaplatin group than the cisplatin group. Conclusions: This proposed study will be the first RCT to evaluate whether lobaplatin-based chemoraiotherapy will have beneficial effects, compared with cisplatin-based chemoradiotherapy, on complete remission rate, PFS, OS, AEs and quality of life for FIGO stage II and III cervical cancer.

• Korean Journal of Head & Neck Oncology
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• v.25 no.2
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• pp.138-142
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• 2009

Introduction : Although bilateral exploration has been thought to be the standard therapeutic modality for primary hyperparathyroidism(pHPT) due to the admirable cure rate, questions have remained as to whether bilateral neck exploration for all patients with pHPT is needed because 80-85% of patients with pHPT have a single parathyroid adenoma. If the diseased parathyroid can be determined preoperatively, a directed and minimal operation is appropriate using the recent innovations of preoperative diagnosis and operation techniques for parathyroid diseases, the radio-guided parathyroid surgery(RGPS) is one of the standards. In especial, RGPS has been reported beneficial in special circumstances, such as in recurrent disease, ectopic parathyroid, and in mediastinal parathyroid. It can be also useful for the parathyroid disease in previously explored or irradiated neck. Material and Methods : We experienced 2 cases of pHPT successfully treated by RGPS in who previously underwent extensive neck dissection and concomitant external or internal radiotherapy. We adopted and modified the technique described by Dr. James Norman at the University of South Florida-the minimally invasive parathyroidectomy using intraoperative nuclear mapping with 99mTc-sestamibi scanning and radioactivity detection probe. Results : We acquired the successful results for these patients. Conclusion : RGPS is thought to be the alternative technique for the patients with prior central neck exploration and irradiation.

• Fire Science and Engineering
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• v.22 no.5
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• pp.72-78
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• 2008

The mass loss rate and heat release rate of EPS sandwich panel cores were analysed using variable external irradiation level. The experimental materials were exposed to incident heat fluxes form 20 to 50 kW/$m^2$. For the measurement of mass loss rate and heat release rate, the size of specimen was $100mm{\times}100mm{\times}50mm$ and the samples were 3 different kinds. The combustion heat were carried out from the Oxygen bomb calorimeter and the mass loss rate and heat release rate were carried out from the Mass loss calorimeter according to ISO 5660-1. As the results of this study, the mass loss rate of Type A, B, and C were 2.7 g/$m^2s$, 2.8 g/$m^2s$, and 2.3 g/$m^2s$ and the heat release rate of Type A, B, and C were 58.23 kW/$m^2$, 47.19 kW/$m^2$, and 50.06 kW/$m^2$ respectively at the heat flux of 50 kW/$m^2$. In conclusion, when the heat release characteristics applied to a classification system of Canada, Type A and C can be classified grade C-3, and Type C can be classified grade C-2 from all data of this study.

• Korean Journal of Veterinary Research
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• v.45 no.2
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• pp.139-149
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• 2005

In order to study about the lobule and layer formation and cell migration of the mouse cerebellum from at the birth to 15th day effected by 2.5, 5 and 10 Gy r-raddiation at the 19th pregnancy. The routine tissue preparation and staining procedure, Immunohistochemical staining method by the several antibody and western brotting method were utilized from the birth to the15th day. The results were as followings. 1. The body and cerebellum weights were more slowly increase of the the 2.5 Gy, 5 Gy and 10 Gy irradiation group compare to the control group, and the health condition of the 2.5 Gy group was a little bad. but the 10 Gy group was more severe and begun to die from the 12th day after birth. 2. The thickness, proliferation and migration of the 2.5, 5 and 10 Gy irradiated external granular cells from the maginal zone to the medullary area forming the molecular layer from the 6th day to the 15th day after birth were thinner, weaker and more slower according to the radiated dosages than the control group in the cresyl violet staining. 3. The proliteration, migration and lobulation of the 5 Gy radiated groups from the first day to the 15th day after birth were more weak, incomplete and irregular shape in the immunostaining with Dab, Cdk5, P35, calbindin and Zebrin antibody. 4. In the western blotting analysis using the Reelin, Dab, Cdk5 and P35 antibody. The Bands were in the 60 KD, 80 KD, 33 KD and 35 KD, and there were no differences between the control and irradiated groups in the molecular band except the Reelin. 5. As a results, the proliferation and migration of the outer granular and purkinje cells, and lobulation of the cerebellum by the several dosaege of the ${\gamma}$-ray radiation were proportionally incomplete according to dosage.

• Journal of Radiation Protection and Research
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• v.29 no.2
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• pp.97-104
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• 2004

MIRD-type Korean adult male phantom, 'KMIRD' was constructed to calculate Korean-specific dosimetric quantities for radiation protection consideration. The external shape of KMIRD was based on national physical standard data of Korean. KMIRD has thicket trunk than MIRD5 and arm models divided from trunk. The height and weight of the KMIRD are 171 cm and 63.8 kg. ICRP23 data were referred to constitute organs and tissues of KMIRD. However nine organs were constructed based on Korean reference data provided by Radiation Health Research Institute. In the present study, the MCNPX2.3 Monte Carlo transport code was combined with KMIRD to calculate dose conversion coefficients for photon in the energy range from 0.05 to 10 MeV. The simulated irradiation geometries are broad parallel photon beams in AP, PA, LLAT and RLAT direction. Absorbed dose conversion coefficients were compared with data calculated with MIRD5, MIRD-type phantom based on ICRP23 reference man. In some organs, the discrepancies between two phantoms amount up to nearly 30%. The effective doses conversion coefficients of KMIRD are lower than those of MIRD5. The dose discrepancies between two MIRD-type phantoms ate because of physical differences between Korean and Western, also geometric differences between two phantoms. KMIRD should be revised using the full set of Korean reference data of all organs. The developed MIRD-type Korean adult male phantom can be applied to dose assessment of internal exposure.