• The Journal of Korean Society for Radiation Therapy
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• v.29 no.1
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• pp.93-101
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• 2017

Purpose: In breast cancer radiotherapy, brass mesh bolus has been recently studied to overcome disadvantage of conventional bolus. The purpose of this study is to investigate the stability of first introduced the brass mesh in the country, and evaluate the skin surface dose of that. Materials and Methods: The measurement of skin surface dose was evaluated to verify similar thickness of the Brass mesh bolus that compared conformal tissue equivalent bolus with 5 mm thickness. We used 6 MV photons on an ELEKTA VERSA linear accelerator and optically stimulated luminescent dosimeter (OSLD). In addition, two opposed beam using IMRT phantom was applied to comparative study of brass mesh bolus between tissue equivalent bolus. Results: The results showed that similar thickness of the Brass mesh bolus was 3 mm compared with 5 mm tissue equivalent bolus by measuring the skin surface dose of solid phantom. The surface dose for IMRT thorax phantom using 3 mm brass mesh bolus was about 1.069 times greater than that using tissue equivalent bolus. Conclusion: In this study, we found that the brass mesh bolus improved better reduction of skin sparing effect and dose uniformity than tissue equivalent bolus. However evaluation for various clinic cases should be investigated.

• Archives of Craniofacial Surgery
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• v.21 no.4
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• pp.229-236
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• 2020

Background: Oncologic resection of the scalp confers several obstacles to the reconstructive surgeon dependent upon patient-specific and wound-specific factors. We aim to describe our experiences with various reconstructive methods, and delineate risk factors for coverage failure and complications in the setting of scalp reconstruction. Methods: A retrospective chart review was conducted, examining patients who underwent resection of fungating scalp tumors with subsequent soft-tissue reconstruction from 2003 to 2019. Patient demographics, wound and oncologic characteristics, treatment modalities, and outcomes were recorded and analyzed. Results: A total of 189 patients were appropriate for inclusion, undergoing a range of reconstructive methods from skin grafting to free flaps. Thirty-three patients (17.5%) underwent preoperative radiation. In all, 48 patients (25.4%) suffered wound site complications, 25 (13.2%) underwent reoperation, and 47 (24.9%) suffered from mortality. Preoperative radiation therapy was an independent risk factor for wound complications (odds ratio [OR], 2.85; 95% confidence interval [CI], 1.1-7.3; p=0.028) and reoperations (OR, 4.45; 95% CI, 1.5-13.2; p=0.007). Similarly, the presence of an underlying titanium mesh was an independent predictor of wound complications (OR, 2.49; 95% CI, 1.1-5.6; p=0.029) and reoperations (OR, 3.40; 95% CI, 1.2-9.7; p=0.020). Both immunosuppressed status (OR, 2.88; 95% CI, 1.2-7.1; p=0.021) and preoperative radiation therapy (OR, 3.34; 95% CI, 1.2-9.7; p=0.022) were risk factors for mortality. Conclusion: Both preoperative radiation and the presence of underlying titanium mesh are independent risk factors for wound site complications and increased reoperation rates following oncologic resection and reconstruction of the scalp. Additionally, preoperative radiation, along with an immunosuppressed state, may predict patient mortality following scalp resection and reconstruction.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.10
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• pp.150-161
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• 2013

This paper presents a new system which produces high resolution 3D contents by capturing multiview images of an object using multiple cameras, and estimating geometric and texture information of the object from the captured images. Even though a variety of multiview image-based 3D reconstruction systems have been proposed, it was difficult to generate high resolution 3D contents because multiview image-based 3D reconstruction requires a large amount of memory and computation. In order to reduce computational complexity and memory size for 3D reconstruction, the proposed system predetermines the regions in input images where an object can exist to extract object boundaries fast. And for fast computation of a visual hull, the system represents silhouettes and 3D-2D projection/back-projection relations by chain codes and 1D homographies, respectively. The geometric data of the reconstructed object is compactly represented by a 3D segment-based data format which is called DoCube, and the 3D object is finally reconstructed after 3D mesh generation and texture mapping are performed. Experimental results show that the proposed system produces 3D object contents of $800{\times}800{\times}800$ resolution with a rate of 2.2 seconds per frame.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.719-724
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• 1994

This paper describes a hybrid surface-based method for smooth 3D surface approximation to a sequence of 2D cross sections. The resulting surface is a hybrid G $^{1}$ surface represented by a mesh of triangular and rectangular Bezier patches defined on skinning, branching, or capping regions. Each skinning region is approximated with a closed B_spline surface, which is transformed into a mesh of Bezier patches. Triangular G $^{1}$ surfaces are constructed over brabching and capping regions such that the transitions between each capping regions such that the transitions between each triangular surface and its neighboring skinning surfaces are G $^{1}$ continuous. Since each skinning region is represented by an approximated rectangular C $^{2}$ suface instead of an interpolated trctangular G $^{[-1000]}$ surface, the proposed method can provide more smooth surfaces and realize more efficient data reduction than triangular surfacebased method.

• The Journal of the Korean dental association
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• v.15 no.2
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• pp.127-132
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• 1977

• Proceedings of the Korean Information Science Society Conference
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• 2000.10b
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• pp.502-504
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• 2000

본 논문은 연결정보가 없는 거리영상으로부터 DSM(Displaced Subdivision Mesh)을 복원하는 기술을 제안한다. DSM은 메쉬의 표면정보를 메쉬 분할법으로 생성한 부드러운 표면과의 차이값으로 표현할 수 있으므로 메쉬를 표현하는 데이터 크기를 획기적으로 줄일 수 있으며, 거리영상에 근접한 3차원 모델 복원기술에 효율적으로 적용될 수 있다. 제안 알고리즘은 기존 방법에서 사용하던 전역적 에너지 최소화 과정을 기하 해석적인 방법으로 대체하여 빠르게 메쉬를 복원할 수 있으며, 복원된 메쉬는 Remeshing을 거치지 않고 바로 다단계 표현으로 변환이 가능하다. 또한 입력 데이터를 고려한 라플라시안을 이용하여 거리영상에 최대한 근접하면서 지역적인 곡률이 최소화된 DSM을 생성한다. 이렇게 복원된 DSM은 메쉬 편집, 압축, 렌더링, 애니메이션 등 여러 응용분야에서 사용될 수 있다.

• Journal of the Korea Computer Graphics Society
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• v.15 no.2
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• pp.1-8
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• 2009

This paper introduces a virtual dress up system, according to user's input model and garment image. At first step, we deform the garment image by using skeleton structures and ARAP method. Next step, sampling the boundary points and find their matching vertices which are used for optimizing the boundary fitting. In 2D rendering of the dress up, they have some unrealistic results, so we reconstruct the garment mesh to the 3D mesh. Rendering from the reconstructed 3D mesh, we can get the final dress up result. We present that our system produce a visually plausible and well-fitted virtual dress up results.

• Journal of Veterinary Clinics
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• v.39 no.6
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• pp.378-383
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• 2022

A 3-year-old, 24-kg intact female Border Collie was referred for a toe-touch weight-bearing stance, intermittent weight-bearing lameness, and moderate pain reaction of the right forelimb on physical examination and right humerus olecranon avulsion fracture on diagnostic imaging examination. Surgical repair was performed using tension band wiring to re-attach the triceps tendon and distal olecranon. Migration of the distal olecranon fragment was observed due to comminuted fracture of the fragment 5-days after surgery, and revision surgery was performed. The tension-relieving sutures were passed through the pre-drilled hole in the olecranon, and the polyester mesh was augmented to the suture region, covering the triceps tendon and olecranon drilling hole using the Krackow suture pattern. The elbow joint was immobilized using a type IA transarticular external fixator, which was removed 8 weeks after surgery. Fourteen weeks after surgery, no lameness was observed on gait evaluation. At follow-up after 7 months, the distal olecranon fragment had stabilized, and no lameness was observed.

• Journal of Korean Neurosurgical Society
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• v.50 no.4
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• pp.357-362
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• 2011

Objective : To report our experience with pyogenic spondylitis treated with anterior radical debridement and insertion of a titanium mesh cage and to demonstrate the effectiveness and safety of the use of a titanium mesh cage in the surgical management of pyogenic spondylitis. Methods : We retrospectively analyzed the clinical characteristics of 19 patients who underwent surgical treatment in our department between January 2004 and December 2008. The average follow-up period was 11.16 months (range, 6-64 months). We evaluated risk factors, cultured organisms, lab data, clinical outcomes, and radiographic results. Surgical techniques for patients with pyogenic spondylitis were anterior radical debridement and reconstruction with titanium mesh cage insertion and screw fixation. All patients received intravenous antibiotics for at least 6 weeks postoperatively, and some patients received oral antibiotics. Results : The infections resolved in all of the patients as noted by normalization of their erythrocyte sedimentation rates and C-reactive protein levels. The mean pain score on a Visual Analog Scale was 7.8 (range, 4-10) before surgery and 2.4 (range, 1-5) after surgery. The Frankel grade was improved by one grade in seven patients. After surgery, the average difference of the angle was improved about $6.96^{\circ}$ in all patients. At the last follow-up, the mean loss of correction was $4.86^{\circ}$. Conclusion : Anterior radical debridement followed by the placement of instrumentation with a titanium mesh cage may be a safe and effective treatment for selected patients with pyogenic spondylitis. This surgical therapy does not lead to recurrent pyogenic spondylitis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.29 no.4
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• pp.249-256
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• 2003

The lack of sufficient oral mucosa available for intra-oral reconstruction has been dealt with by the use of skin or oral mucosa grafts harvested from donor sites but grafts requires more than one surgical procedures and could cause donor site morbidity. Many investigators have attempted to increase available soft tissue by tissue engineered skin or oral mucosa replacements for clinical applications. But, reconstructed mucosa by several methods have low physical properties such as rolling and contraction. The aims of this study were to develope an in vitro experimental model that maintains an epithelial-mesenchymal interaction by organotypic raft culture, and to characterize biologic properties of three-dimensionally cultured oral mucosa embedded with Polydioxanone mesh by histological and immunohistochemical analysis. The results were as follows; 1. Oral mucosa reconstructed by three-dimensional organotypic culture revealed similar morphologic characteristics to equvalent normal oral mucosa in the point that they show stratification and differentiation. 2. The expression of cytokeratin 10/13 and involucrin in the cultured tissue showed the same pattern with normal oral mucosa suggesting that organotypic co-culture condition is able to induce cellular differentiation. 3. After insertion of polydioxanone mesh, increased tensile strength were observed. These results suggest that three-dimensional organotypic co-culture of the oral mucosa cell lines with the dermal equvalent consisting type I collagen and fibroblasts reproduce the morphologic and immunohistochemical characteristics similar to those in vivo condition. And increased physical properties by use of polydioxanone mesh will helpful for clinical applications.