• The Journal of Korean Society for Radiation Therapy
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• v.12 no.1
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• pp.20-25
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• 2000

The accuracy of the target localization was evaluated by conventional and spiral CT in stereotactic radiosurgerv. Conventional and spiral CT images were obtained with geometrical phantom, which was designed to produce exact three-dimensional coordinates of several objects within 0.1mm error range. Geometrical phantom was attached by BRW headframe, intermediate head ring, and CT localizer. Twentv-seven slices of conventional CT image were scanned at 3 mm slice thickness. Spiral CT images were scanned at 3 mm slice thickness from the pitch value 1 to 3, and twenty-seven slices of image were obtained per each the pitch value. These CT images were transferred to a treatment planning system(X-knife, Radionics) by ethernet, Three-dimensional coordinates of these images measured from the treatment planning system were compared to known values of geometrical phantom. The mean localization error of the target localization of conventional CT was 1.4mm. In case of spiral CT, the error of the target localization was within 1.6mm from the pitch value 1 to 1.3, but was more than 30mm above the pitch value 1.5. In conclusion, as the localization error of spiral CT was increased in high pitch value compared to conventional CT, the application of spiral CT will be with caution in stereotactic radiosurgery.

• The korean journal of orthodontics
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• v.42 no.6
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• pp.329-334
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• 2012

Objectives: To determine the prevalence of incidental maxillary sinus findings in a large sample of orthodontic patients by cone-beam computed tomography (CBCT) with a wide field of view and assess the relationships of such abnormalities with age and gender. Methods: Five hundred thirteen CBCT scans obtained for orthodontic diagnosis and treatment planning in a Northern Italian population (N = 513; 292 female and 221 male subjects; 1,026 maxillary sinuses) were studied. The frequencies of pseudocysts and mucosal thickening of the maxillary sinus were recorded. Logistic regression analysis was used to determine the influence of age and gender on these abnormalities. Results: Pseudocysts were detected in 52 patients (10.1%) and 59 sinuses (5.75%). Mucosal thickening was observed in 206 patients (40.1%) and 258 sinuses (25.1%). Gender and age were significantly associated with pseudocysts (p = 0.027) and mucosal thickening (p < 0.001), respectively. Conclusions: Half of the orthodontic patients had incidental maxillary sinus findings. Men were more likely to show pseudocysts, and older patients (aged 41 - 60 years) were more likely to show mucosal thickening.

• Radiation Oncology Journal
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• v.35 no.2
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• pp.180-184
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• 2017

Patients with locally advanced lung cancer and very limited pulmonary function (forced expiratory volume in 1 second $[FEV1]{\leq}1L$) have dismal prognosis and undergo palliative treatment or best supportive care. We describe two cases of locally advanced node-positive non-small cell lung cancer (NSCLC) patients with very limited lung function treated with induction chemotherapy and moderate hypofractionated image-guided radiotherapy (Hypo-IGRT). Hypo-IGRT was delivered to a total dose of 45 Gy to the primary tumor and involved lymph nodes. Planning was based on positron emission tomography-computed tomography (PET/CT) and four-dimensional computed tomography (4D-CT). Internal target volume (ITV) was defined as the overlap of gross tumor volume delineated on 10 phases of 4D-CT. ITV to planning target volume margin was 5 mm in all directions. Both patients showed good clinical and radiological response. No relevant toxicity was documented. Hypo-IGRT is feasible treatment option in locally advanced node-positive NSCLC patients with very limited lung function ($FEV1{\leq}1L$).

• The Journal of the Korean dental association
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• v.52 no.3
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• pp.132-138
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• 2014

The emergence of Cone Beam Computed Tomography(CBCT) in the late 1990s represented an innovative advancement in the field of dental and maxillofacial radiology because it greatly reduced the radiation exposure to patients and offered 3D images easily. The 3D information generated by this technique brings the potential of improved diagnosis and treatment planning for a wide range of clinical applications in dentistry. The use of CBCT includes diagnosis and surgical assessment of the orofacial hard tissue lesions, dental implant treatment planning and postoperative evaluation, TMJ assessment, diagnosis of craniofacial fracture, orthodontics, endodontics, and so on. All CBCT examinations should be justified on an individualized needs. The clinical benefits to the patient for each CBCT scan must outweigh the potential risks associated with exposure to ionizing radiation. CBCT scans should be taken with initially obtained medical and dental histories of patients and a close clinical examination. CBCT should be considered as an imaging alternative of other conventional radiography in cases where the anatomical structures of interest may not be seen. The smallest possible field of view(FOV) and the lowest setting of tube current and scan time should be chosen, and the entire images scanned should be interpreted by a qualified expert.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2002.09a
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• pp.208-210
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• 2002

In a treatment planning for actual patients with a complex internal structure, we often expect that proton beams, which pass through both a bolus and the heterogeneity in body, will form complex dose distributions. Therefore, the accuracy of the calculated dose distributions has to be verified for such a complex object. Then dose distributions formed by proton beams passing through both the bolus and phantoms simulating a clinical heterogeneity in patients were measured using a silicon semiconductor detector. The calculated results by the range-modulated pencil beam algorithm (RMPBA) produced large errors compared with the measured dose distributions since dose calculation using the RMPBA could not predict accurately the edge-scattering effect both in the bolus and in clinical heterogeneous phantoms. On the other hand, in spite of this troublesome heterogeneity, calculated results by the simplified Monte Carlo (SMC) method reproduced the experimental ones well. It is obvious that the dose-calculations by the SMC method will be more useful for application to the treatment planning for proton therapy.

• KIEAE Journal
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• v.13 no.2
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• pp.101-106
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• 2013

As the number of aged people increase, hospitals specializing in elderly cares have also increased very rapidly. Therefore it is necessary to improve the quality of these hospitals for the elderly people in order to enhance the function of these hospitals not only for conventional treatment but also for recovery and convalescence. To study such trend and needs, this study researched on planning for Elderly Hospital's Atrium that provides a space for the elderly people so that they may enjoy the natural environment while being supported from diverse aspects for long term cares and sustained living, and tried to find out design solutions based on users' demand through questionnaire survey and interviews both with the management of the elderly hospital and the inpatients or the users. As a result of this study, it was revealed that each user showed his or her own respective characteristics concerning his or her expectation about the environment of their using spaces, and according to this result the strategic direction and design plan could be drawn. Based on plans for this Elderly Hospital's Atrium specializing in cares for the elderly people, useful information will be provided for caring, treatment and recovering environment of the elderly hospitals in future considering not only the conventional medical and technical services but also the inpatients' or the users' physical, psychological and social factors.

• Journal of Korean Society of Rural Planning
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• v.26 no.2
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• pp.95-106
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• 2020

The Onishi model is an objective indicator which can be used to evaluate the relevance of city environmental management in regard to the capacities and processing status of existing urban infrastructure. This study is to analyze the facility carrying capacity and processing status of Jeju Island, a famous tourist site in South Korea. General variables covered by the Onishi model are considered, including water supply, wastewater treatment, waste disposal, and air pollution. Furthermore, the facility carrying capacities for transportation, such as airports and ports, as well as accommodations are assessed as variables pertinent to the characteristics of Jeju island. With the annual number of tourists exceeding that of residents on the island, more facilities for sewage treatment and waste disposal are required. Furthermore, transportation and accommodations used by tourists have already exceeded their capacity. For the future sustainability of Jeju Island, a plan will be needed for adjusting the volume of tourists based on the capacity of each relevant facility.

• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3816-3823
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• 2022

This work analyzed the dosimetric difference between the intensity modulated radiotherapy (IMRT), partial/single/double-arc volumetric modulated arc therapy (PA/SA/DA-VMAT) techniques in treatment planning for treating more than one target of lung cancer at different isocenters. IMRT and VMAT plans at different isocenters were created systematically using a Harold heterogeneous lung phantom. The conformity index (CI), homogeneity index (HI), gradient index (GI), dose-volume histogram and mean and maximum dose of the PTV were calculated and analyzed. Furthermore, the dose-volume histogram and mean and maximum doses of the OARs such as right lung, contralateral lung and non GTV were determined from the plans. The IMRT plans showed the superior target dose coverage, higher mean and maximum values than other VMAT techniques. PA-VMAT technique shows more lung sparing and DA-VMAT increases the V_5/10/20 values of contralateral lung than other VMAT and IMRT techniques. The IMRT technique achieves highly conformal dose distribution to the target than other VMAT techniques. Comparing to the IMRT plans, the higher V_5/10/20 and mean lung dose were observed in the contralateral lung in the DA-VMAT.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.2
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• pp.150-156
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• 2004

The etiology of the obstructive sleep apnea includes the various factors such as anatomical abnormality in upper airway, craniofacial structure, obesity and personal habit. To establish reasonable treatment plan, multi-department approach is should be emphasized because the treatment modality is depend on the result of analysis for degree & site of obstruction and various behavioral factors. In Sleep Clinic in Keimyung University Medical Center, the standard of care for sleep apnea patient was established according to the Standard of practice committee of Americal Sleep Disorders Association. After one year experience of comprehensive approach for sleep apnea we could achieve following recommendation for the treatment. 1) The multi-department examination and diagnosis could prevent unnessesary treatment because the treatment plan could be established under comprehensive discussion. 2) Determination of the site of obstruction is important for treatment planning. However, no single determinant could be found. We expect multi-department approach can reduce the mistake in detection of obstruction. 3) Further evaluation of treatmet outcome should be succeeded to establish Korean standard of care for sleep apnea treatment.

• Journal of the Korean Society for Heat Treatment
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• v.24 no.2
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• pp.77-81
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• 2011

Aluminum nitride (AlN) thin films were prepared by using nitrogen ion beam assisted reactive radio frequency (RF) magnetron sputtering on the glass substrates without intentional substrate heating. After deposition, the effect of nitrogen ion beam energy on the structural and optical properties of AlN films were investigated by x-ray diffraction (XRD), atomic force microscope (AFM) and UV-Vis. spectrophotometer, respectively. AlN films deposited with $N^+$ ion irradiation at 100 eV show the higher (002) peak intensity in XRD pattern than other films. It means that $N^+$ ion energy of 100 eV is the favorable condition for low temperature crystallization. AFM images also show that surface average roughness is increased from 1.5 to 9.6 nm with $N^+$ ion energy in this study. In an optical observation, AlN films which deposited by $N^+$ ion beam energy of 100 eV show the higher transmittance than that of the films prepared with the other $N^+$ ion beam conditions.