• Archives of Plastic Surgery
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• 제39권5호
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• pp.546-550
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• 2012

Background This study was designed to introduce the feasibility of toe tissue transfer without venous outflow for fingertip reconstruction. Methods Five cases of fingertip defects were treated successfully with this method. Four cases were traumatic fingertip defects, and one case was a hook-nail deformity. The lateral pulp of a great toe or medioinferior portion of a second toe was used as the donor site. An arterial pedicle was dissected only within the digit and anastomosis was performed within 2 cm around the defect margin. The digital nerve was repaired simultaneously. No additional dissection of the dorsal or volar pulp vein was performed in either the donor or recipient sites. Other surgical procedures were performed following conventional techniques. Postoperative venous congestion was monitored with pulp temperature, color, and degree of tissue oxygen saturation. Venous congestion was decompressed with a needle-puncture method intermittently, but did not require continuous external bleeding for salvage. Results Venous congestion was observed in all the flaps, but improved within 3 or 4 days postoperatively. The flap size was from $1.5{\times}1.5cm^2$ to $2.0{\times}3.0cm^2$. The mean surgical time was 2 hours and 20 minutes. A needle puncture was carried out every 2 hours during the first postoperative day, and then every 4 hours thereafter. The amount of blood loss during each puncture procedure was less than 0.2 mL. In the long-term follow-up, no flap atrophy was observed. Conclusions When used properly, the free toe tissue transfer without venous anastomosis method can be a treatment option for small defects on the fingertip area.

• 전기전자학회논문지
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• 제18권4호
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• pp.478-484
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• 2014

본 논문에서는 Kinect Depth 카메라에서 손가락의 방향을 이용한 마우스 커서의 위치 선정에 관한 새로운 방법을 제안한다. 제안하는 방법은 손가락의 방향이 카메라를 향해 있을 경우는 거리변환을 이용한 손의 중점좌표를 이용한다. 손가락의 방향이 카메라를 향해 있지 않을 경우에는 손가락의 끝점 좌표를 이용한다. 손의 중점좌표는 전처리를 거친 영상의 거리변환 결과에서 가장 밝은 픽셀의 좌표를 이용하여 구한다. 손가락의 방향이 카메라를 향해 있을 경우에는 손가락의 끝점 좌표와 손의 중점 좌표 사이의 거리가 가까워지므로 중점좌표를 이용하여, 위치 선정의 정확도를 향상시킬 수 있게 된다. 손가락의 끝점 좌표는 손 영역만을 추출한 영상에서 팔 부분을 제거하여 영상의 중심에서 가장 멀리 떨어져있는 픽셀을 이용하여 구한다. 본 논문에서 제안하는 커서 위치 선정의 정확도를 측정하기 위해 임의의 5개의 기준 좌표를 선정하고 기준 좌표와 측정된 마우스 좌표사이의 오차를 500회 반복하여 측정하여 에러율을 측정한 결과, 평균 11 % 미만의 오차율을 나타내어 제안한 방법의 정확도를 확인할 수가 있었다.

• Archives of Reconstructive Microsurgery
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• 제18권1호
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• pp.27-30
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• 2009

Purpose: Recently, replantation of fingertip amputation, Zone I by Yamano classification, is still difficult because digital arteries branch into small arteries and also digital veins are hard to separate from the immobile soft tissue. However the replantation of fingertip in adults is a well-established procedure, but the replantation in infant or child is still uncommon. Therefore we present one case of replantation of the fingertip of the small finger in 12-months-old patient. Methods: We experienced a 12-months-old male amputation of small finger. It had been amputated completely at the level of Zone I by Yamano classification. Replantation was performed using the arteryonly technique with neither vein nor nerve repair. Because the artery has been damaged, it is still possible to make a direct suture by transposing the arterial arch in an inverted Y to I arterial configuration. Venous drainage was provided by an external bleeding method with partial nail excision and repaired margin for approximately 7 days. Results: We were performed replantation in infant with only-arterial anastomosis successfully, result in good recovery of aesthetic and functional outcome. Conclusion: In conclusion, although fingertip injury was difficult to replantation in infant and child, we must try it. Because of its functional and cosmetic advantage.

• Journal of Computational Design and Engineering
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• 제1권4호
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• pp.289-297
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• 2014

Although big-sized markers are good for accurate marker recognition and tracking, they are easily occluded by other objects and deteriorate natural visualization and level of immersion during user interaction in AR environments. In this paper, we propose an approach to exploiting the use of rectangular markers to support tangible AR interaction based on fingertip touch using small-sized markers. It basically adjusts the length, width, and interior area of rectangular markers to make them more suitably fit to longish objects like fingers. It also utilizes convex polygons to resolve the partial occlusion of a marker and properly enlarges the pattern area of a marker while adjusting its size without deteriorating the quality of marker detection. We obtained encouraging results from users that the approach can provide better natural visualization and higher level of immersion, and be accurate and tangible enough to support a pseudo feeling of touching virtual products with human hands or fingertips during design evaluation of digital handheld products.

• Archives of Reconstructive Microsurgery
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• 제7권2호
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• pp.108-113
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• 1998

Reverse digital artery flaps were performed successfully to resurface the fingertip defect in 13 patients as noninnervated pattern and in 12 patients as innervated pattern from March 1993 to February 1996. No loss of flap in this series was noted. Refinements in flap design and surgical technique resulted in favourable functional and ethetic results. The average two-point discrimination of the reconstructed fingertip was 7.2mm and 4.5mm in the noninnervated and innervated flaps, respectively. This flap is an one of the ideal and reliable option for reconstruction of fingertip defects.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.370-375
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• 1992

An algorithm for the notion planning of the robotic hand is proposed to generate finite displacements and changes in orientation of objects by considering sliding effects between the fingertips and the object at contact points. Specifically, an optimization problem is firstly solved to find minimum contact forces and minimum joint velocities to impart a desired motion to the object at each time step. Then the instantaneous relative velocity at the contact point is found by determining velocities of the fingertip and the velocity of the object at the contact point. Finally time derivatives of the surface variables and contact angle of the fingertip and the object at the present time step is computed using the Montana's contact equation to find the contact parameters of the fingertip and the object at the next time step. To show the validity of the proposed algorithm, a numerical example is illustrated by employing the robotic hand manipulating a sphere with three fingers each of which has four joints.

• 한국컴퓨터정보학회논문지
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• 제18권8호
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• pp.65-75
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• 2013

본 논문에서는 깊이 영상만을 이용하여 손 영역 추적 및 손 끝점 검출 방법을 제안한다. 조명 조건의 영향을 제거하고 빠르고 안정적인 정보 획득을 위해 깊이 정보만을 이용하는 추적 방법을 제안하고, 영역 확장 방법을 통해 추적 과정 중에 발생할 수 있는 오류에 대한 판단 방법과 다양한 제스처 인식에 응용이 가능한 손 끝점 검출 방법을 제안한다. 먼저 추적점을 찾기 위해 중심점 전이 과정을 통해 최근접점을 찾고 그 점으로부터 영역 확장을 통해 손 영역과 경계선을 검출한다. 그리고 영역 확장을 통해 획득한 무효경계선의 비율을 이용하여 추적영역에 대한 신뢰도를 계산함으로써 정상 추적 여부를 판단한다. 정상적인 추적인 경우, 검출된 손 영역으로부터 윤곽선을 추출하고 곡률 및 RANSAC, 컨벡스 헐(Convex-Hull)을 이용하여 손 끝점을 검출한다. 마지막으로 성능 검증을 위해 다양한 상황에 따른 정량적, 정성적 분석을 통해 제안하는 추적 및 손 끝점 검출 알고리즘의 효율성을 입증한다.

• 한국정보과학회논문지:소프트웨어및응용
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• 제29권11호
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• pp.851-859
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• 2002

본 연구는 마우스의 입력을 사람의 손동작으로 대체하는 휴먼마우스 시스템을 위한 새로운 손끝 좌표 추적기법과 마우스 포인터 움직임 결정법을 제안한다. 손끝좌표 추적에는 얼굴영역 추적을 위해 제안되었던 CAMSHIFT 알고리즘을 개선하여 적용하였다. 정확한 손 영역 검출을 위하여 각 사용자의 환경에 최적화된 피부영역 컬러 정보를 얻을 수 있는 실시간 피부영역 학습과 손의 자유로운 움직임으로 인하여 발생하는 손 영역의 크기 및 방향변화를 고려한 영역제한 기법을 적용하였다. 또한 손의 주축을 이용한 손끝좌표 계산법을 통해 빠르고 정확하게 손끝의 위치를 찾을 수 있다. 실시간 손끝좌표 검출에는 처리속도의 한계가 있어 얻어지는 좌표의 연속성이 결여되어 마우스 포인터의 움직임이 연결되지 않는 문제점이 있다. 연속적인 마우스 포인터의 움직임 표현을 위해 손끝좌표의 이동거리를 통해 마우스 포인터의 속도와 가속도를 계산하여 마우스 포인터의 운동방정식을 정의하고 이를 이용하여 마우스 포인터의 위치를 결정한다. 제안한 알고리즘을 적용하여 실험한 결과 빠르고 정확한 손끝좌표 추적과 마우스 포인터의 자연스러운 움직임이 가능함을 보였다.

• Archives of Reconstructive Microsurgery
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• 제16권2호
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• pp.75-81
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• 2007

Introduction: Microsurgical replantation of amputated digit have become common procedure in recent years. However replantation of fingertip amputation, Zone I by Yamano classification, is still difficult because digital arteries branch into small arteries and also digital veins are hard to separate from the immobile soft tissue. So, fingertip amputation was covered by volar V-Y flap, composite graft, cross finger flap and groin flap. But patients who have been treated by these methods experience shortening of digit, nail deformity, excessive tenderness and persistent pain. Replantation could solve most of these problems. Material & Methods: In our department, from March 2004 to August 2007, 36 digits in 32 patients with complete amputation at distal to nail base were replanted using a microsurgical technique. Results: The overall survival rate of the replanted finger was 75%. Venous anastomosis was possible in 8 cases and impossible in 28 cases. In latter cases external bleeding technique was applied with medical leech. Conclusion: After replantation, a few patient complained decreased sensibility, nail deformity and cold intolerance. But most of patients were satisfied with the functional and cosmetic appearance of the viable replanted digits. We believe the replantation should be the first choice in fingertip amputation.

• Archives of Plastic Surgery
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• 제47권1호
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• pp.54-61
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• 2020

Background Conventional methods of external bleeding for congested fingertip replants exhibit notable problems, including uncontrollable bleeding and unpredictable survival of the replant. We have added a local injection of heparin calcium to the routine use of systemic heparinization for inducing external bleeding. We retrospectively examined patients who underwent external bleeding using our method. Methods Local subcutaneous injections of heparin calcium were made in 15 congested replants in addition to systemic heparinization. Each injection ranged from 500 to 5,000 U. The average duration of the injections was 4.1 days. Surgical outcomes were analyzed and compared with a control group of patients who underwent external bleeding without heparin calcium. Results The overall survival rate was 93.3%, which was higher than that of the control group (83.3%), but the difference was not statistically significant (P=0.569). The survival rate for subzones I and II by the Ishikawa subzone classification was 100%, whereas it was 87.5% in subzones III and IV. No statistically significant difference was observed. The rate of partial necrosis was 0% in subzones I and II, whereas it was significantly higher (66.7%) in subzones III and IV (P=0.015). The mean total blood loss via external bleeding was 588 g in 10 fingers. No patients required blood transfusion. Conclusions Congestion of a replanted fingertip can be successfully managed without blood transfusion by our method. Although complete relief from congestion in replants in subzones I and II is achievable, there is a higher risk of partial necrosis in subzones III and IV.