• Archives of Craniofacial Surgery
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• v.17 no.2
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• pp.45-50
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• 2016

Extensive surgical resection of the aerodigestive track can result in a large and complex defect of the oropharynx, which represents a significant reconstructive challenge for the plastic surgery. Development of microsurgical techniques has allowed for free flap reconstruction of oropharyngeal defects, with superior outcomes as well as decreases in postoperative complications. The reconstructive goals for oral and oropharyngeal defects are to restore the anatomy, to maintain continuity of the intraoral surface and oropharynx, to protect vital structures such as carotid arteries, to cover exposed portions of internal organs in preparation for adjuvant radiation, and to preserve complex functions of the oral cavity and oropharynx. Oral and oropharyngeal cancers should be treated with consideration of functional recovery. Multidisciplinary treatment strategies are necessary for maximizing disease control and preserving the natural form and function of the oropharynx.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.8 s.185
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• pp.89-99
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• 2006

In this paper a new shape reconstruction method that allows us to construct surface models from very large sets of points is presented. In this method the global domain of interest is divided into smaller domains where the problem can be solved locally. These local solutions of subdivided domains are blended together according to weighting coefficients to obtain a global solution using partition of unity function. The suggested approach gives us considerable flexibility in the choice of local shape functions which depend on the local shape complexity and desired accuracy. At each domain, a quadratic polynomial function is created that fits the points in the domain. If the approximation is not accurate enough, other higher order functions including cubic polynomial function and RBF(Radial Basis Function) are used. This adaptive selection of local shape functions offers robust and efficient solution to a great variety of shape reconstruction problems.

• Journal of Biomedical Engineering Research
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• v.32 no.1
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• pp.15-24
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• 2011

While Compton imaging is recognized as a valuable 3-D technique in nuclear medicine, reconstructing an image from Compton scattered data has been of a difficult problem due to its computational complexity. The most complex and time-consuming computation in Compton camera reconstruction is to perform the conical projection and backprojection operations. To alleviate the computational burden imposed by these operations, we investigate a rebinning method which can convert conical projections into parallel projections. The use of parallel projections allows to directly apply the existing deterministic reconstruction methods, which have been useful for conventional emission tomography, to Compton camera reconstruction. To convert conical projections into parallel projections, a cone surface is sampled with a number of lines. Each line is projected onto an imaginary plane that is mostly perpendicular to the line. The projection data rebinned in each imaginary plane can then be treated as the standard parallel projection data. To validate the rebinning method, we tested with the representative deterministic algorithms, such as the filtered backprojection method and the algebraic reconstruction technique. Our experimental results indicate that the rebinning method can be useful when the direct application of existing deterministic methods is needed for Compton camera reconstruction.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.8
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• pp.164-170
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• 2004

The skin movement artifacts are referred to as the relative motion of skin with respect to the motion of underlying bones. This is of great importance in joint biomechanics or internal kinematics of human body. This paper describes a novel experiment that measures the skin movement of a hand based on MR(magnetic resonance) images in conjunction with surface modeling techniques. The proposed approach consists of 3 phases: (1) MR scanning of a hand with surface makers, (2) 3D reconstruction from the MR images, and (3) registration of the 3D models. The MR images of the hand are captured by 3 different postures. And the surface makers which are attached to the skin are employed to trace the skin motion. After reconstruction of 3D models from the scanned MR images, the global registration is applied to the 3D models based on the particular bone shape of different postures. The results of registration are then used to trace the skin movement by measuring the positions of the surface markers.

• Proceedings of the Korean Vacuum Society Conference
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• 1993.07a
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• pp.45-46
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• 1993

• Proceedings of the KSMRM Conference
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• 1997.10a
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• pp.29-29
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• 1997

• Proceedings of the Korean Vacuum Society Conference
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• 2004.08a
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• pp.53-53
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• 2004

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.82.3-82
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• 1998

• Archives of Plastic Surgery
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• v.46 no.1
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• pp.34-38
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• 2019

Background Acellular dermal matrices (ADMs) have recently become widely used in breast reconstruction, but the correlation between the final expander volume and the surface area of the ADM is not well understood. In this study, the expansion of the surface area of ADM and the expander volume was studied retrospectively in cases of acellular dermis-assisted tissue expander breast reconstruction. Methods Twenty cases of immediate breast reconstruction using an ADM-assisted tissue expander from January 2015 to December 2015 were evaluated. In all 20 cases, CGCryoDerm was used as the matrix, with a thickness of 1-3 mm. No slit incisions were made. Finally, the proportional increase in the area of the fully expanded ADM was compared to that of the tissue expander volume. Results The proportional increase in the ADM surface area was calculated to be from 1.1 to 2.46, with a mean value of 1.7. Additionally, under the assumption that the expander had a spherical shape, the increase in its radius (the cube root of its volume) was assessed. The range of the proportional increase in the expander radius was 1.1 to 2.24, with a mean value of 1.66. The proportional increase in the radius of the expanded ADM surface area ranged from 1.04 to 1.34, with a mean ratio of 1.28. Conclusions The results of this study confirmed that the ADM expanded when the tissue expander was inflated. However, the ADM expanded to a lesser extent than the tissue expander, indicating that the muscle and other tissues expanded more than the ADM when the tissue expander was inflated.

• Archives of Plastic Surgery
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• v.38 no.5
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• pp.655-662
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• 2011

Purpose: The anterolateral thigh flap is versatile flap for soft-tissue reconstruction for defects located at various sites of the body. This useful flap offers a thick and vascular fascia lata component with large amounts that can be soft tissue coverage for different reconstructive purposes. We present our clinical experience with the use of vascular fascia lata, combined with anterolateral thigh flap for various reconstructive goals. Methods: From April 2008 to February 2011, we transferred anterolateral thigh flaps with fascia lata component to reconstruct soft-tissue defects for different purposes in 11 patients. The fascia lata component of the flap was used for tendon gliding surface in hand/forearm reconstruction in 4 patients, for reconstruction medial and lateral patellar synovial membrane and retinaculum in 2 patients, for reconstruction of plantar aponeurosis in the foot in 2 patients, for reconstruction of fascial and peritoneal defect in the abdominal wall in 2 patient, and for dural defect reconstruction in the scalp in the remaining one. Results: Complete loss of the flap was not seen in all cases. Partial flap necrosis occurred in 2 patients. These complications were treated successfully with minimal surgical debridement and dressing. Infection occurred in 1 patient. In this case, intravenous antibiotics treatment was effective. Conclusion: Anterolateral thigh flap has thick vascular fascia with large amounts. This fascial component of the flap is useful for different reconstructive aims, such as for tendon, ligament, aponeurosis defects, abdominal wall or dura reconstruction. It should be considerated as an important advantage of the flap, together with other well-known advantages.