• Archives of Plastic Surgery
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• 제38권1호
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• pp.35-42
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• 2011

Purpose: Blow-out fractures can be reduced using various methods. The orbital reconstruction technique using a balloon under endoscopic control has advantages over other methods. However, this method has some problems too, such as postoperative follow-up, management of the balloon catheter, and reduction of the posterior orbital floor. Thus, we developed a simple, effective method for orbital floor reduction that involves molding and shaping the antral balloon catheter. Methods: A 0, 30, or $70^{\circ}$, 4-mm endoscope was placed though a two-point, 5-mm maxillary antrostomy. The balloon catheter is placed directly at the orbital apex to reconstruct the anterior shelf (spherical shape), while it is turned in a U-shape towards the anterior maxilla for the posterior shelf (elliptical shape). Orbital floor defects, compound or comminuted fractures are reconstructed with alloplastic materials through an open lid incision under the endoscopic control. Results: This technique was applied to ten patients with orbital floor fractures: five anterior shelf and five posterior shelf fracture, respectively. Four of the patients had zygomatico-orbital fractures, while the rest had isolated orbital floor fractures. Two patients were given porous polyethylene implants Synpor$^{(R)}$) and three underwent reconstruction with a resorbable mesh plate. No complication associated with this technique was identified. Conclusion: The freestyle placement and selection of a urinary balloon catheter under endoscopic control and the preoperative estimation of the volume enhanced the stabilization of the orbital contour. This method improves the adaptation of the orbital floor without the risk of injuring the surrounding orbital contents, dissecting blindly, or using sharp traction. One drawback of this method is the patient's discomfort from the catheter during treatment.

• 대한두개안면성형외과학회지
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• 제21권3호
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• pp.166-170
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• 2020

Background: The standard treatment of nasal bone fractures in pediatric patients is closed reduction. Conservative treatment is sometimes performed, but poses a risk of nasal deformity. The aim of this study was to evaluate the outcomes of bone remodeling in pediatric nasal fractures. Methods: Information was extracted from the medical records of patients under 12 years of age who received conservative treatment for a nasal bone fracture and underwent follow-up computed tomography (CT) examinations. The initial fracture and its outcomes over time were graded as excellent, good, or fair according to the malalignment, displacement, or irregularity of the fractured segments. The outcomes of remodeling were evaluated through changes in the grade of the fracture between initial and subsequent CT scans. Results: The review identified 16 patients between March 2015 and December 2019. Their mean age was 6.2 years, and the average follow-up period was 4.9 months. Three of the five patients with a plane I frontal impact showed improved outcomes of remodeling from good to excellent, and the remaining two patients, improved from fair to good. Eight of the 11 patients with plane I lateral impacts showed improved outcomes, from good to excellent, while one patient, improved from fair to good, one patient, improved from fair to excellent, and one patient showed no interval changes. Conclusion: In 15 of these 16 patients with non-severe fractures, the bony contour improved through remodeling, without surgical intervention. Therefore, we suggest that conservative treatment is a feasible option for mild pediatric nasal fractures.

• 한국항해항만학회지
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• 제27권4호
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• pp.359-366
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• 2003

이 논문은 대한민국 해양사고 예보 시스템 (K-MACFOS)을 개발하기 위한 해양사고 수량화 D/B (N-D/B) 구성과 분석에 관하여 기술하였다. K-MACFOS의 주목표는 일기예보와 같이 해양사고의 예측건수와 위험수준을 방송하기 위한 것이다. 해양사고 데이터는 1990년부터 2000년까지 1년간 위도 33oN∼35oN와 경도 124oE∼127oE의 대한민국 서남해안 일대에서 발생한 총 724건을 수집하였고, 14가지 수량화변환 척도를 이용하여 양적 데이터로 변환하였다. 컬러 콘도-맵 가시화를 이용한 통계분석을 통하여 N-D/B의 유효성과 연구대상 해역의 사고특징을 검토하였다. 또한, 올바른 N-D/B 분석과 정확한 해양사고 건수 예측을 위한 최적 적용기간 선정 방법을 제안하였다.

• 대한두개안면성형외과학회지
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• 제20권4호
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• pp.233-238
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• 2019

Background: The open reduction of craniofacial bone fractures requires internal fixation using metal plates and screws, which have been considered the gold standard. However, metal implants pose a risk of palpation, protrusion, and foreign body reaction, and they may require an additional operation for removal. Recently, good results have been reported for absorbable implants which complement the disadvantages of metal implants. This study presents the results of using absorbable mesh, plates, and screws with cyanoacrylate for more accurate and firmer fixation of comminuted fractures of the maxilla. Methods: In total, 235 patients underwent operations for comminuted fractures of the maxilla. From January 2012 to December 2014, absorbable mesh and screws were used in 114 patients, while from January 2015 to December 2017, absorbable mesh, plates, and screws with cyanoacrylate were used in 121 patients. Open reduction of the bone fragments was performed, after which absorbable implants were accurately molded and fixed by screws. Results: All patients underwent postoperative computed tomography scans, which showed highly accurate reduction and firm fixation in the patients who underwent procedures using absorbable implants, screws, and cyanoacrylate. There were no postoperative complications or cases of abnormal facial contour. Conclusion: When absorbable implants and screws are used for maxillary fractures, no additional surgery to remove the metal plate is required. In addition, the use of cyanoacrylate enables accurate and firm fixation of the tiny bone fragments that cannot be fixed with screws.

• 대한방사선기술학회지:방사선기술과학
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• 제46권3호
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• pp.239-246
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• 2023

In this study, we assessed the effect of reduction of tumor volume in the head and neck cancer by using RANDO phantom in Static Intensity-Modulated Radiation Therapy (S-IMRT) and Volumetric-Modulated Arc Therapy (VMAT) planning. RANDO phantom's body and protruding volumes were delineated by using Contour menu of Eclipse™ (Varian Medical System, Inc., Version 15.6, USA) treatment planning system. Inner margins of 2 mm to 10 mm from protruding volumes of the reference were applied to generate the parameters of reduced volume. In addition, target volume and Organ at Risk (OAR) volumes were delineated. S-IMRT plan and VMAT plan were designed in reference. These plans were assigned in the reduced volumes and dose was calculated in reduced volumes using preset Monitor unit (MU). Dose Volume Histogram (DVH) was generated to evaluate treatment planning. Conformity Index (CI) and R² in reference S-IMRT were 0.983 and 0.015, respectively. There was no significant relationship between CI and the reduced volume. Homogeneity Index (HI) and R² were 0.092 and 0.960, respectively. The HI increased when volume reduced. In reference VMAT, CI and R² were 0.992 and 0.259, respectively. There was no relationship between the volume reduction and CI. On the other hand, HI and R² were 0.078 and 0.895, respectively. The value of HI increased when the volume reduced. There was significant difference (p<0.05) between parameters (D_mean and D_max) of normal organs of S-IMRT and VMAT except brain stem. Volume reduction affected the CI, HI and OAR dose. In the future, additional studies are necessary to incorporate the reduction of the volume in the clinical setting.

• Clinics in Shoulder and Elbow
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• 제26권1호
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• pp.93-106
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• 2023

Reverse total shoulder arthroplasty (RTSA) emerged as a new concept of arthroplasty that does not restore normal anatomy but does restore function. It enables the function of the torn rotator cuff to be performed by the deltoid and shows encouraging clinical outcomes. Since its introduction, various modifications have been designed to improve the outcome of the RTSA. From the original cemented baseplate with peg or keel, a cementless baseplate was designed that could be fixed with central and peripheral screws. In addition, a modular-type glenoid component enabled easier revision options. For the humeral component, the initial design was an inlay type of long stem with cemented fixation. However, loss of bone stock from the cemented stem hindered revision surgery. Therefore, a cementless design was introduced with a firm metaphyseal fixation. Furthermore, to prevent complications such as scapular notching, the concept of lateralization emerged. Lateralization helped to maintain normal shoulder contour and better rotator cuff function for improved external/internal rotation power, but excessive lateralization yielded problems such as subacromial notching. Therefore, for patients with pseudoparalysis or with risk of subacromial notching, a medial eccentric tray option can be used for distalization and reduced lateralization of the center of rotation. In summary, it is important that surgeons understand the characteristics of each implant in the various options for RTSA. Furthermore, through preoperative evaluation of patients, surgeons can choose the implant option that will lead to the best outcomes after RTSA.

• Asian-Australasian Journal of Animal Sciences
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• 제20권4호
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• pp.598-604
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• 2007

The current study was conducted to evaluate carcass characteristics, objectives and sensory meat qualities of Hanwoo longissimus muscle as affected by ultimate pH. Twenty-four steers and bulls ($556{\pm}53$ kg and $0.63{\pm}0.32$cm for live weight and backfat thickness, respectively) were used. As there was a linear relationship (r = 0.77) between lean meat color and ultimate pH, cattles were thus segregated into normal $pH{\leq}5.8$, Normal, n = 13) and DFD (pH>5.8, n = 11) groups. Normal pH group had significantly (p<0.05) higher carcass weight, marbling score and backfat thickness than those for high pH group, while fat color and lean meat color were inverse. In principle component analysis for co-ordinates of DFD and normal meats, fat color, lean meat color, texture, time to pH 6.2 and pH at 24 h postmortem were associated with the positive range of the first factor (67.5%) while backfat thickness marbling score and temperature at 24 h were placed in negative values. The rate constant of decline in pH (pH k) did not differ between the two groups, implying that initial pH (i.e., pH at slaughtering) differed between two groups. Contour mapping of pH k between pH at 1 and 24 h postmortem indicated that high pH k was related to lower pHs at 1 and 24 h postmortem. This suggested that the high pH cattles (i.e., DFD cattle) resulted from their own potential. Although the time to reach pH 6.2 was significantly (p<0.05) shorter for normal meat (i.e., 3.2 h) than that for DFD one (i.e., 19.8 h), there were no significantly differences in both WB-shear force and sensory attributes. Given that the experimental animals were sampled from a similar group, which implies a similar myoglobin pigment content, the current data suggested that pre- and post-slaughter animal handling likely had a significant effect on ultimate pH and consequently meat color of Hanwoo longissimus muscle, and also small animals with lower marbling score and backfat thickness had a higher risk for DFD meat.

• Asian Pacific Journal of Cancer Prevention
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• 제16권12호
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• pp.5019-5024
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• 2015

Background: The purpose of this study was to assess the dosimetric and clinical feasibility of volumetric modulated arc based hypofractionated stereotactic radiotherapy (RapidArc) treatment for large acoustic schwannoma (AS >10cc). Materials and Methods: Ten AS patients were immobilized using BrainLab mask. They were subject to multimodality imaging (magnetic resonance and computed tomography) to contour target and organs at risk (brainstem and cochlea). Volumetric modulated arc therapy (VMAT) based stereotactic plans were optimized in Eclipse (V11) treatment planning system (TPS) using progressive resolution optimizer-III and final dose calculations were performed using analytical anisotropic algorithm with 1.5 mm grid resolution. All AS presented in this study were treated with VMAT based HSRT to a total dose of 25Gy in 5 fractions (5fractions/week). VMAT plan contains 2-4 non-coplanar arcs. Treatment planning was performed to achieve at least 99% of PTV volume (D99) receives 100% of prescription dose (25Gy), while dose to OAR's were kept below the tolerance limits. Dose-volume histograms (DVH) were analyzed to assess plan quality. Treatments were delivered using upgraded 6 MV un-flattened photon beam (FFF) from Clinac-iX machine. Extensive pretreatment quality assurance measurements were carried out to report on quality of delivery. Point dosimetry was performed using three different detectors, which includes CC13 ion-chamber, Exradin A14 ion-chamber and Exradin W1 plastic scintillator detector (PSD) which have measuring volume of $0.13cm^3$, $0.009cm^3$ and $0.002cm^3$ respectively. Results: Average PTV volume of AS was 11.3cc (${\pm}4.8$), and located in eloquent areas. VMAT plans provided complete PTV coverage with average conformity index of 1.06 (${\pm}0.05$). OAR's dose were kept below tolerance limit recommend by American Association of Physicist in Medicine task group-101(brainstem $V_{0.5cc}$ < 23Gy, cochlea maximum < 25Gy and Optic pathway <25Gy). PSD resulted in superior dosimetric accuracy compared with other two detectors (p=0.021 for PSD.

• 대한토목학회논문집
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• 제36권2호
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• pp.231-243
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• 2016

본 연구에서는 이용 가능한 자료가 제약이 있는 실제 농업용 저수지 붕괴에 대한 2차원 홍수범람해석의 적용성을 보여주었다. 연구 대상 유역은 2013년 파이핑 현상에 의해 붕괴가 발생한 경주 산대저수지 및 하류부 지역이다. 본 연구에서는 1차원 모형으로 파이핑 붕괴에 따른 유출수문곡선을 도출하고, 이를 2차원 수치모형의 상류단 경계조건으로 사용하여 모의를 수행하였다. 2차원 홍수파 해석을 위해서 수치지도와 위성자료를 합성하여 지형자료를 구성하였고, 건물, 도로, 운동장 등의 형상을 정확하게 반영하기 위해 $3m{\times}3m$ 크기의 정형격자를 사용하여 모의를 수행하였다. 현장조사된 저수지 붕괴유출량, 범람범위, 홍수심 그리고 홍수 전파시간과 계산치를 비교하고, 합리적인 범위의 결과를 보여줌으로써 모형의 검증을 수행하였다. 또한, 격자크기, 건물 및 조도계수가 홍수범람에 미치는 영향을 분석하였다. 본 연구는 향후 농업용 저수지의 붕괴해석 및 하류부의 비상대처계획 수립에 기초자료로 활용될 수 있을 것으로 기대된다.

• 한국의학물리학회지:의학물리
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• 제27권2호
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• pp.64-71
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• 2016

삼차원 프린터(3DP)를 이용하여 환자맞춤형 전자선 치료용 볼루스(patient specific customized bolus, PSCB)를 제작하는 절차를 고안하고 제안된 방법으로 제작한 PSCB의 선량 정확도를 평가했다. 치료계획장치에서 치료계획표적용적(PTV)에 적합한 전자선 빔과 조사면 크기를 선택하고 초기 선량계산을 수행했다. 계산된 선량분포를 기반으로 PSCB를 그리고 재계산을 수행했다. 수 차례 반복을 통해 최상의 PSCB를 설계하고 설계된 윤곽자료를 DICOMRT 프로토콜을 이용해 자체 제작한 변환프로그램으로 전송했다. PSCB의 윤곽자료는 자체 변환프로그램을 이용해 3DP에서 인식 가능한 파일(STL 포맷)로 변환한 후 3DP를 이용해 제작했다. PSCB의 유용성을 검증하기 위해 2명의 가상 환자(오목, 볼록 유형)를 생성했고 각각의 환자에 가상의 PTV와 정상장기(OAR)을 생성했다. 3D-PSCB 를 사용했을 때와 사용하지 않았을 때의 선량체적히스토그램(DVH)와 선량 특성을 비교했다. 3D-PSCB 제작의 정확도를 분석하기 위해 필름 선량측정을 통해 선량 정확도를 평가했다. 치료계획 결과와 필름을 이용한 선량분포를 중첩한 후 빔 중심축에서의 심부선량곡선을 구했고 감마분석(3% 선량 오차와 3 mm 거리오차)을 수행 했다. 2명의 가상환자 모두에서 PSCB를 사용한 경우 PTV 선량은 큰 차이를 보이지 않았다. PSCB를 사용할 경우 PSCB를 사용하지 않는 경우에 비해 OAR의 최대 선량, 최소선량, 평균선량은 각각 평균 9.7%, 36.6%, 28.3% 감소했다. 처방선량의 90% 선량($V_{90%}$)을 받는 OAR의 용적은 PSCB를 적용할 경우 약 99% 낮아졌다(14.40 vs $0.1cm^3$). 또한 처방선량의 80% 선량을 받는 OAR 체적도 PSCB를 사용할 경우 약 91% 줄었다(42.6 vs $3.7cm^3$). 감마분석 결과(3%, 3 mm) 오목 및 볼록 볼루스를 적용한 경우 각각 95%, 98% 통과율(pass rate)을 보였다. 3DP를 이용해 PSCB를 제작하는 절차를 정립하고 선량적 정확도를 평가해서 임상적용이 가능한 만족할 만한 결과를 얻었다. 3DP 기술의 빠른 발전에 힘입어 PSCB의 임상적용이 좀 더 쉬워지고 적용대상이 확장될 것으로 생각된다.