• 제목/요약/키워드: Skin occlusion

검색결과 47건 처리시간 0.028초

The Relationship between Oxygen Saturation and Color Alteration of a Compromised Skin Flap: Experimental Study on the Rabbit

  • Prasetyono, Theddeus O.H.;Adianto, Senja
    • Archives of Plastic Surgery
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    • 제40권5호
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    • pp.505-509
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    • 2013
  • Background The aim of this study was to collect important data on the time of oxygen saturation change in relation to skin flap color alteration using non-invasive pulse oximetry to evaluate its ability to provide continuous monitoring of skin flap perfusion. Methods An experimental study on the monitoring of blood perfusion of 20 tube-island groin flaps of 10 male New Zealand rabbits was performed using pulse oximetry. The animals were randomly assigned to one of two groups representing a blockage of either arterial or venous blood flow. The oxygen saturation change and clinical color alteration were monitored from the beginning of vessel clamping until the saturation became undetectable. The result was analyzed by the t-test using SSPS ver. 10.0. Results The mean times from the vessel clamping until the saturation became undetectable were $20.19{\pm}2.13$ seconds and $74.91{\pm}10.57$ seconds for the artery and vein clamping groups, respectively. The mean time of the clinical alteration from the beginning of vein clamping was $34.5{\pm}11.72$ minutes, while the alteration in flaps with artery clamping could not be detected until 2.5 hours after clamping. Conclusions The use of neonate-type reusable flex sensor-pulse oximetry is objective and effective in early detection of arterial and vein blockage. It provides real-time data on vessel occlusion, which in turn will allow for early salvaging. The detection periods of both arterial occlusion and venous congestion are much earlier than the color alteration one may encounter clinically.

개심술 후에 발생한 급성 복부 대동맥 차단 -1예 보고- (Acute Abdominal Aortic Occlusion after Open Heart Surgery - A case report -)

  • 한원경;조준용;이종태
    • Journal of Chest Surgery
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    • 제38권10호
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    • pp.710-713
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    • 2005
  • 급성복부대동맥 폐쇄는 드물지만, 응급을 요하며 높은 사망률과 이환율을 보이는 혈관질환이다. 늦은 진단은 예후에 심각한 영향을 미치게 된다. 승모판 협착, 심방세동, 관상동맥협착, 삼첨판 역류 및 심방중격결손으로 인한 개심슬을 받은 60세 여자가 술 후 13일에 하지의 감각이상, 마비, 심한 통증을 호소하였다. 배꼽 아래부터 발끝에 이르는 피부가 얼룩덜룩하였으며 하지의 맥박이 촉지되지 않았다. 저자들은 다중 검출 컴퓨터 단층 촬영을 이용하여 급성 복부 대동맥 폐쇄를 진단하고, 응급 혈색전 제거 및 대동맥-양측 대퇴동맥 우회로술로 성공적으로 치료하였다.

Real-Time Rotation-Invariant Face Detection Using Combined Depth Estimation and Ellipse Fitting

  • Kim, Daehee;Lee, Seungwon;Kim, Dongmin
    • IEIE Transactions on Smart Processing and Computing
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    • 제1권2호
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    • pp.73-77
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    • 2012
  • This paper reports a combined depth- and model-based face detection and tracking approach. The proposed algorithm consists of four functional modules; i) color-based candidate region extraction, ii) generation of the depth histogram for handling occlusion, iii) rotation-invariant face region detection using ellipse fitting, and iv) face tracking based on motion prediction. This technique solved the occlusion problem under complicated environment by detecting the face candidate region based on the depth-based histogram and skin colors. The angle of rotation was estimated by the ellipse fitting method in the detected candidate regions. The face region was finally determined by inversely rotating the candidate regions by the estimated angle using Haar-like features that were robustly trained robustly by the frontal face.

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Effect of Occlusion upon Rat Skin on the Activities of Cutaneous Oxygen Radical Metabolizing Enzymes in Rats

  • Han, Sun-Il;Yoon, Chong-Guk;Cho, Hyun-Gug
    • 대한의생명과학회지
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    • 제7권2호
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    • pp.71-77
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    • 2001
  • To evaluate the effect of occlusive skin on the activity of cutaneous oxygen free radical metabolizing enzymes in rats, the dorsal skin was covered with closed glass chamber shaped petri dish, 46 mm in diameter and 10 mm in height and sealed by an adhesive. Five day-occluded group showed more increased activity of xanthine oxidase (XO) than that of control, and the activity of five day-occluded group was higher than that of ten day-occluded group. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) were significantly higher in ten day-occluded group than in control or five day-occluded group. All the more, five day-occluded group showed the decreasing tendency of SOD and GPx activities compared to those of control. On the other hand, the cerrous perhydroxide deposits were observed in the intercellular space of the stratum basale in five day-occluded group under the electronic microscope using a cytochemistry method. Futhermore, the degree of cerrous perhydroxide reaction was lower in ten day-occluded group than in five day-occluded group. In conclusion, the increased XO activity and the decreased SOD and GPx activities are likely to responsible far the accumulation of $H_2O_2$ in five day-occluded group.

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A Real-time Face Tracking Algorithm using Improved CamShift with Depth Information

  • Lee, Jun-Hwan;Jung, Hyun-jo;Yoo, Jisang
    • Journal of Electrical Engineering and Technology
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    • 제12권5호
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    • pp.2067-2078
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    • 2017
  • In this paper, a new face tracking algorithm is proposed. The CamShift (Continuously adaptive mean SHIFT) algorithm shows unstable tracking when there exist objects with similar color to that of face in the background. This drawback of the CamShift is resolved by the proposed algorithm using Kinect's pixel-by-pixel depth information and the skin detection method to extract candidate skin regions in HSV color space. Additionally, even when the target face is disappeared, or occluded, the proposed algorithm makes it robust to this occlusion by the feature point matching. Through experimental results, it is shown that the proposed algorithm is superior in tracking performance to that of existing TLD (Tracking-Learning-Detection) algorithm, and offers faster processing speed. Also, it overcomes all the existing shortfalls of CamShift with almost comparable processing time.

Incidental finding of subclavian artery occlusion and subsequent hypoplastic internal mammary artery as a candidate recipient vessel in DIEP flap breast reconstruction

  • Seong, Ik Hyun;Woo, Kyong-Je
    • Archives of Plastic Surgery
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    • 제46권6호
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    • pp.599-602
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    • 2019
  • We report a case of autologous breast reconstruction in which a thoracodorsal vessel was used as a recipient vessel after a hypoplastic internal mammary vessel was found on preoperative computed tomography (CT) angiography. A 46-year-old woman with no underlying disease was scheduled to undergo skin-sparing mastectomy and breast reconstruction using a deep inferior epigastric artery perforator flap. Preoperative CT angiography showed segmental occlusion of the right subclavian artery with severe atherosclerosis and calcification near the origin of the internal mammary artery, with distal flow maintained by collateral branches. The thoracodorsal artery was selected to be the recipient vessel because CT showed that it was of adequate size and was not affected by atherosclerosis. The patient experienced no postoperative complications, and the flap survived with no vascular complications. The breasts were symmetrical at a 6-month follow-up. This case highlights that preoperative vascular imaging modalities may help surgeons avoid using diseased vessels as recipient vessels in free flap breast reconstructions.

피부색과 변형된 다중 CAMShift 알고리즘을 이용한 실시간 휴먼 트래킹 (Real-Time Human Tracking Using Skin Area and Modified Multi-CAMShift Algorithm)

  • 민재홍;김인규;백중환
    • 한국항행학회논문지
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    • 제15권6호
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    • pp.1132-1137
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    • 2011
  • 본 논문에서는 사람의 신체 일부분을 추적하는 시스템을 위해서 피부영역을 추출하고 여러 개의 영역을 추적하는 다중 CAMShift 알고리즘(Multi Continuously Adaptive Mean Shift Algorithm)을 제안하였다. 입력 영상에서 피부영역을 추출하기 위해 영상의 RGB의 특정값을 기준으로 피부색에 적응적인 임계값을 적용하였다. 이때 적용된 피부영역을 양손, 얼굴 등에 초기 윈도우를 설정하였다. 이 영역들을 추적함에 있어 영역들 사이에 폐색 영역을 회피하기 위해 가우시안 배경 모델(Gaussian Background Model)을 사용하여 각 추적 영역들을 제한하였다. 또한 폐색영역에 가중치를 부가하여 확률분포영상에서 중심값을 이동시켜 폐색 영역을 회피하였다. 실험 결과 다중 물체들에 강인한 추적을 보이고 유사한 색상을 갖는 물체의 폐색 시에도 우수한 결과를 보임을 확인하였다.

칼만 필터와 가중탐색영역 CAMShift를 이용한 휴먼 바디 트래킹 및 자세추정 (Human Body Tracking and Pose Estimation Using CamShift Based on Kalman Filter and Weighted Search Windows)

  • 민재홍;김인규;황승준;백중환
    • 한국항행학회논문지
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    • 제16권3호
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    • pp.545-552
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    • 2012
  • 본 논문에서는 사람의 신체 일부분을 추적하는 시스템을 위해서 피부영역을 추출하고 여러 개의 영역을 추적하는 칼만 필터와 가중 탐색 영역을 이용한 다중 CAMShift 알고리즘(KWMCAMShift)을 제안한다. 배경모델을 구성하고 손과 얼굴의 피부색영역을 탐색 영역으로 하는 CAMShift를 제안한다. 이때 CAMShift의 유동적인 탐색영역을 안정화하기 위해 칼만 필터를 이용한다. 손과 얼굴 등이 상호 겹쳐지는 경우 탐색영역의 손실을 막기 위해 주 탐색영역과 비 탐색영역에 대한 가중치를 부가하여 서로 폐색 영역에 대한 회피 알고리즘을 제안한다. 얼굴 영역과 양손의 영역을 중심으로 인간의 자세를 추정하여 어깨와 손과의 관계로 팔꿈치를 추정하였고, 가우시안 배경 모델에 생성되는 그림자를 제거하여 발끝을 찾아 신체 전체를 추정하였다. 제안된 KWMCAMShift 알고리즘을 적용하였을 때 폐색 시에도 96.82%의 인식률을 보였으며 실시간이 가능하였다.

Haar 웨이블릿 특징과 피부색 정보를 이용한 실시간 얼굴 검출 및 추적 방법 (A Real-Time Face Detection/Tracking Methodology Using Haar-wavelets and Skin Color)

  • 박영경;서해종;민경원;김중규
    • 정보처리학회논문지B
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    • 제13B권3호
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    • pp.283-294
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    • 2006
  • 본 논문은 Haar 웨이블릿 특징과 피부색 정보를 이용한 실시간 얼굴 검출 및 추적 방법을 제안한다. 검출과 추적이 각기 다른 특징들을 이용해 이루어졌던 기존 방법과는 달리 본 논문에서는 피부색 정보와 Haar 웨이블릿 특징을 검출과 추적에 동시에 이용하고 두 특징들을 효과적으로 융합함으로써 빠르고 강인한 추적을 가능하게 한다. 제안된 방법은 검출과 추적에 동일한 특징을 이용함에도 불구하고 표본화에 기반을 둔 Condensation 알고리즘의 특징으로 인해 검출 방법만을 적용했을 때 검출하지 못하는 얼굴의 회전이나 가려짐 등의 문제를 효과적으로 해결한다. 특히, 얼굴의 위치와 함께 크기 변화를 효과적으로 추적하기 때문에 얼굴의 위치 및 크기를 정확하게 알아야 하는 얼굴 인식이나 표정인식 등의 다양한 어플리케이션에 이용되기에 용이하다. 제안된 방법은 복잡한 배경 및 다양한 얼굴 자세 등의 변화에 대한 테스트를 통해 효율성을 검증한다.

Guinea Pig Maximization Test에 의한 옻나무 추출액(Rhus-II)의 접촉 알러지성 자극에 관한 연구 (The Observation of the Skin Contact Allergic Sensitization Test of Rhus-II with Guinea Pig Maximization Test)

  • 최창순;한동운
    • 한국식품위생안전성학회지
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    • 제20권1호
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    • pp.13-17
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    • 2005
  • The purpose of the present study was to investigate differences in the sensitizing potential of Rhus Veniciflua(Rhus-II), when tested by the guinea pig maximization test(GPMT) and Freund's complete adjuvant test(FCAT) with an identical, intradermal induction concentration. A new grading classification of the sensitization potential is proposed. The GPMT was conducted according to OECD guideline $\#406$, using a multiple-dose design and test results were analysed with logistic regression analysis. During the induction stage, we injected intradermally each three site 0.1 ml(l mg/animal) test material, 0.1 ml complete Freund's adjuvant and 0.lml the test agent emulsified in the adjuvant. 7 days later, we induced weak sensitization with $10\%$ sodium lauryl sulfate(SLS) and applide 1ml(l0mg/animal) test agent topically on the same site and made a tight occlusion. 14 days later we challenged with 1 ml(l 0mg/animal) of test material on the flank and observed ant 24 hours and 48 hours later. The results were also observed $0\%$ at 24 hours challenge. The results observed 48 hours after challenge were the identical. These data indicated that, although Rhus-II is a no contact allergen. It was reported that the skin sensitization by Rhus-II was not detected the skin sensitization in the guinea pig maximization test (GPMT). Consequently, it was confirmed that Rhus-II had no contact allergic sensitization in guinea pig maximization test.