• 제목/요약/키워드: Effective size

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아래볼기동맥 관통가지피판을 이용한 궁둥 욕창의 치료 (Ischial Pressure Sore Reconstruction Using Inferior Gluteal Artery Perforator Flap)

  • 김영석;강종화;이원재;탁관철
    • Archives of Plastic Surgery
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    • 제34권2호
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    • pp.209-216
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    • 2007
  • Purpose: The ischial area is by far the most common site of pressure sores found in wheel chair bound paraplegic patients, because greatest pressure is exerted from the body on this area in a sitting position. Even after a series of successful pressure sore treatments, the site is very prone to relapse by the simplest ordinary tasks of everyday life. Therefore, it is crucial to preserve the main pedicle during primary surgery. Various surgical procedures employed to treat pressure sores such as myocutaneous flap and perforator flap have been introduced. After introduction of ischial sore treatment using the inferior gluteal artery perforator (IGAP) has been made, the authors experienced favorable clinical results of patients who have undergone IGAP flap procedure in a three year time period. Methods: A total of 17 patients received IGAP flap surgery in our hospital from January 2003 to May 2006, among which 14 of them being males and 3 females. Surgery was performed on the same site again in 6(35%) patients who had originally relapsed after receiving the conventional method of pressure sore surgery. Patients' average age was 49.4(27-71) years old. Most of the patients were paraplegic(11 cases, 65%) and others were either quadriplegic(4 cases, 23%) or ambulatory(2 cases, 12%). Based on hospital records and clinical photographs, we have attempted to assess the feasibility and practicability of the IGAP flap procedure through comparative analysis of several parameters: size of defective area, treatment modalities, occurrence of relapses, complications, and postoperative treatments. Results: The average follow-up duration of 17 subjects was 25.4 months(5-42 months). All flaps survived without any necrosis. Six cases were relapsed cases from conventional surgical procedures. All of them healed well during our follow-up study. Postoperative complications such as wound dehiscence and fistula developed in some subjects, but all were well healed through secondary treatment. A total of 2 cases relapsed after surgery. Conclusion: The inferior gluteal artery perforator flap is an effective method that can be primarily applied in replacement to the conventional ischial pressure sore reconstructive surgery owing to its many advantages: ability to preserve peripheral muscle tissue, numerous possible flap designs, relatively good durability, and the low donor site morbidity rate.

MRK증후군 환자에서 변형 Singapore피판술을 이용한 질 재건 (Vaginal Reconstruction with Modified Singapore Flap in MRK Syndrome Patients)

  • 김도훈;변재경;문구현;방사익;오갑성;임소영
    • Archives of Plastic Surgery
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    • 제38권5호
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    • pp.616-620
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    • 2011
  • Purpose: Mayer-Rokitansky-Kuster syndrome (MRK) is second common cause of primary amenorrhea. It is a syndrome of vaginal aplasia and Mullerian duct anomaly. Vaginal aplasia varies from agenesis of whole vagina to aplasia of upper 2/3. For reconstructing vagina, various methods are introduced. Gracilis myocutaneous flap was the first attempt in that the flap is used in vaginal reconstruction. Various flap-based vaginal reconstruction methods have been introduced. Modified Singapore flap (pedicled neurovascular pudendal thigh fasciocutaneous flap) is one of those methods that used posterior labial artery as pedicle, and pudendal nerve branch as sensory root. As its donor lies on inguinal crease that is easily hidden and there are benefits on sexual intercourse by early sensory recovery, authors think that modified Singapore flap is effective for young MRK syndrome patients. Methods: Eight patients underwent surgery between 2008 and 2010. The flap was designed on both groin area with external pudendal artery branch as a pedicle. All flaps were fixated in pelvic cavity with absorbable suture, and additional compression on neovaginal wall was supplied by polyvinyl alcohol sponge ($Merocel^{(R)}$). Results: All patients were successfully reconstructed without flap related complications such as congestion or partial flap loss. The average size of the flap (each side) was 69.34 $cm^2$. Polyvinyl alcohol sponge ($Merocel^{(R)}$) was inserted into neovagina for 5 days on every patient. One case of rectal laceration was occurred while making pelvic pocket by OBGY team. Other complications such as lumen narrowing, wound contracture or vaginal prolapsed were not reported during 8 months of follow up. Conclusion: Modified Singapore flap is a sensate fasciocutaneous flap that is thinner than other myocutaneous flap such as VRAM, and more durable over skin graft. Therefore this is a good choice for vaginal reconstruction in MRK syndrome. And known complications of Modified Singapore flap could be reduced with careful procedure and mild compression techniques.

신개발 키토산 제재의 지혈 효과에 대한 비교 (Experimental Assessment of Hemostatic Agents: Comparison with New Developed Chitosan-Based Material)

  • 조영규;이상윤;김태정;임현주;오은정;이수복;최강영;양정덕;조병채;정호윤
    • Archives of Plastic Surgery
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    • 제38권4호
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    • pp.369-375
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    • 2011
  • Purpose: Many hemostatic agents and dressings have been tested with variable degree of success. Chitosan has a positive charge, it attracts red blood cells, which have a negative charge. Our goal is to test the efficacy of new developed chitosan-based hemostatic materials in providing durable hemostasis in a high-flow arterial wound model. Methods: We compared each group with SD rats motality tests and in vitro blood compatibility test by blood clotting index (BCI). We devided the SD rats into 6 groups (N =15) by type of hemostatic agents. A: 100% nonwoven chitosan (degree of the deacetylation: 90%). B: 50% N-acetylation on nonwoven of chitosan gel (degree of the deacetylation: 50%). C: 60% N-acetylation on nonwoven of chitosan ge (degree of the deacetylation: 40%)l. D: Cutanplast$^{(R)}$. E: HemCon$^{(R)}$ F: Gauze. In vivo test, a proximal arterial injury was created in unilateral femoral arteries of 90 anesthetized SD rats. Each materials was made same size and thickness then applied to the injury site for 3 minutes. In vitro test, we compared each group with BCI in human blood. Results: In vivo test, group A showed lower motality rate of 46% than any other groups, Group B and C showed lower motality rate of 60% than group D and E's motality rate of 66%. In vitro test, BCI of group A ($30.6{\pm}1.2$) and B ($29.3{\pm}1.0$) were showed nearly about group D ($29.1{\pm}1.8$) and E ($27.4{\pm}1.6$). Group C ($37.1{\pm}2.0$) showed higher BCI than group A and B, it means group C decreased blood clotting. Conclusion: In conclusion, this study suggests a newly developed chitosan-based hemostatic materials induced durable hemostasis and increased blood clotting, and are considered as effective biologic hemostatic agents.

혈관문합 연습을 위한 보존된 복재정맥의 활용 (Microsurgical Training using Preserved Saphenous Vein)

  • 송제니퍼김;황소민;임광열;정용휘
    • Archives of Plastic Surgery
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    • 제37권4호
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    • pp.391-395
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    • 2010
  • Purpose: Given that the critical nature of the microvascular anastomosis to what is often a long and difficult reconstructive operation, trainees need to have a high level of microsurgical competence before being allowed to perform microsurgery on patients. Some artificial substitutes and dead or live animal models have been used to improve manual dexterity under the operating microscope. Yet, most surgeons are not equipped with such models, so search for easy available and appropriate microsurgical practice model have been an issue. Umbilical artery, placental vessels and gastroepiploic arteries have been previously suggested as a microsurgical training model, which involves other surgical departments. The purpose of this article is to introduce that saphenous vein specimen obtained from varicose vein surgery is useful and has many advantages as training model for the practice of microvascular anastomosis. Methods: The conventional technique using perforation/inversion method with a metallic stripper is widely performed for varicose vein patients. The stripper is inserted through disconnected safeno-femoral junction and retrieved at the knee or the medial side of ankle. The length of saphenous vein specimens removed is about that of one's leg and inversed from inside out. Obtained saphenous vein specimens are re-inversed and cleansed with normal saline, to be readily available for microsurgical practice. Preserved in a squeezed wet saline gauze and refrigerated, frozen or glycerated specimens were investigated into their comparative quality for microsurgical practice. Results: Varicose vein surgery remains one of the common operations performed in the field of plastic surgery. Convenient informed consent regarding the vessel donation can be easily signed. The diameter of the obtained saphenous vein is as variable as 1.5 to 6 mm, which is already stripped, and is in sufficient length corresponding to that of patient's leg. Vessels specimens were available for microsurgical practice within 1 week period when preserved with squeezed wet saline gauze, and the preservation period could be extended monthly by freezing it. Conclusion: Saphenous vein obtained from varicose vein patients provide with variable size of vessel lumen with sufficient length. The practice can be cost effective and does not require microsurgical laboratory. Additionally there is no need of involving other surgical departments in acquiring vessel specimens. Furthermore, simple preservation method of refrigerating for a week or freezing with squeezed wet saline gauze for a month period, allow the saphenous vein obtained after varicose vein surgery as an excellent model for the microsurgical practice.

식생여과대내 침투능력 향상에 따른 오염물질 저감효과에 대한 실험 (Experiment for Reduction Effectiveness of Pollutants with the Improvement of Infiltration Ability in Vegetation Filter Strip)

  • 이영아;최이송;오종민
    • 한국수자원학회논문집
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    • 제40권2호
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    • pp.183-190
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    • 2007
  • 본 연구에서는 식생여과대에 있어서 토양층의 역할에 주목하였으며, 토양 침투량이 증가될 수 있는 구조로 토양층을 변형하여 일반적인 식생여과대에서의 오염저감효과와 비교 분석하였다. 따라서 연구의 최종 목적은 토양층 변화를 통한 식생여과대의 수질개선효과를 일반적인 토양층으로 구성된 식생여과대와 비교, 검토함으로써 보다 효과적인 식생여과대를 조성하고자 하는 것이다. 실험분석 결과, 토양층 변화를 접목시킨 식생여과대는 일반 식생여과대에 비해 표면유출에서 높은 오염물질 저감효과가 있는 것으로 나타났다. 이는 표면유출수 일부가 정류벽을 통과한 후 재상승하여 표면으로 유출되었기 때문으로 판단된다. 그러나 계단형에서의 하부유출수의 경우, 입경이 큰 모래와 자갈을 통과하여 유출이 일어나기 때문에 직선형 식생여과대보다 오염저감효율은 다소 낮게 나타났다. 이를 오염물질 유출부하량의 개념으로 파악해 보면, 하부유출량이 전체 유출유량에 대한 기여도가 계단형(4%)에서 직선형(2%)보다 높기 때문에 계단형에서의 오염물질 저감부하량이 직선형에 비하여 매우 높게 나타났다. 따라서 정류벽과 표면층 변화를 통해 침투량을 증가시킨 식생여과대는 일반적인 식생여과대보다 저감효과가 크고 식생여과대 적용에 필요한 여러 조건(토양의 침투성, 여과대의 넓이 및 길이, 유속 등)을 만족하지 않더라도 충분한 저감효과를 발휘할 수 있을 것으로 기대된다.

Clinical outcome of proton therapy for patients with chordomas

  • Youn, Sang Hee;Cho, Kwan Ho;Kim, Joo-Young;Ha, Boram;Lim, Young Kyung;Jeong, Jong Hwi;Lee, Sang Hyun;Yoo, Heon;Gwak, Ho-Shin;Shin, Sang Hoon;Hong, Eun Kyung;Kim, Han Kyu;Hong, Je Beom
    • Radiation Oncology Journal
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    • 제36권3호
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    • pp.182-191
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    • 2018
  • Purpose: To investigate the clinical outcome of proton therapy (PT) in patients with chordoma. Materials and Methods: Fifty-eight patients with chordoma treated with PT between June 2007 and December 2015 at the National Cancer Center, Korea, were retrospectively analyzed. The median total dose was 69.6 cobalt gray equivalent (CGE; range, 64.8 to 79.2 CGE). Local progression-free survival (LPFS), distant metastasis-free survival (DMFS), overall survival (OS), and disease-specific survival (DSS) rates were calculated by the Kaplan-Meier method. Results: With the median follow-up of 42.8 months (range, 4 to 174 months), the 5-year LPFS, DMFS, OS, and DSS rates were 87.9%, 86.7%, 88.3%, and 92.9%, respectively. The tumor location was associated with the patterns of failure: the LPFS rates were lower for cervical tumors (57.1%) than for non-cervical tumors (93.1%) (p = 0.02), and the DMFS rates were lower for sacral tumors (53.5%) than for non-sacral tumors (100%) (p = 0.001). The total dose was associated with both the LPFS rate and DMFS rate. The initial tumor size was associated with the DMFS rate, but was not associated with the LPFS rate. Three patients had grade 3 late toxicity with none ≥grade 4. Conclusion: PT is an effective and safe treatment in patients with chordomas. The tumor location was associated with the patterns of failure: local failure was common in cervical tumors, and distant failure was common in sacral tumors. Further refinement of PT, such as the utilization of intensity modulated PT for cervical tumors, is warranted to improve the outcome.

가미강활산(加味羌活散)이 집먼지 진드기 추출물로 유도된 NC/Nga mouse의 아토피 피부염에 미치는 영향 (Effect of Kami-kanghwalsan (KKHS) on Atopic Dermatitis-like Skin Lesions Induced in NC/Nga Mouse by Mite Antigen Stimulation)

  • 김윤희;한재경;김윤희
    • 대한한방소아과학회지
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    • 제22권1호
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    • pp.69-93
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    • 2008
  • Objectives The purpose of this study is to investigate the effect of KKHS on atopic dermatitis in an in-vivo experiment using an NC/Nga atopic dermatitis mouse, which has histological and clinical similarities to this condition in humans. Methods To investigate the effect of KKHS on atopic dermatitis (AD), we evaluated atopic dermatitis-like skin lesions by clinical skin index and analyzed immunological parameters in peripheral blood mononuclear cells(PBMCs), splenocytes, draining lymph node(DLN) and performed skin histology in ears and dorsal skin of atopic dermatitis of NC/Nga mouse in vivo. Results In vivo, clinical skin severity score was significantly lower in the KKHS group than in the control group. IgE, IL-6, TNF-${\alpha}$, IgM, IgG2a and IgG2b levels in serum decreased remarkably in the KKHS group than in the control group, and the level of IFN-${\gamma}$ production which is secreted from Th1 cell was increased by KKHS. After this experiment we analyzed immunological cells ($CD3^+$, $CD19^+$, $CD4^+$, $CD8^+$, $CD3^+CD69^+$, $CD4^+CD25^+$ and $CD49b^+$) by flow cytometry. It results that the total absolute number of $CD3^+$, $CD19^+$, $CD4^+$ and $CD8^+$ cells were recovered as much as normal state, and the level of $CD3^+CD69^+$ in isolated DLN and PBMCs were significantly decreased, and total absolute number of $Gr-1^+$, $CD11b^+$ and $CD3^+$ in dorsal skin of NC/Nga mouse were decreased by KKHS. We analyzed ear, DLN, and neck-back skin after biopsy and dyeing by hematoxyline/eosin(H&E), toluidine staining (mast cells marker). KKHS were very effective to the histological symptoms which are in dermal and epidermal thickening, hyperkeratosis and inflammatory cell infiltration. Ear thickness was significantly decreased compared with the control group and the size of inflammatory lymphocytes cells (ILC) and plasma cells (PC) in DLN were also decreased. Conclusions KKHS on atopic dermatitis in an in-vivo experiment using an NC/Nga atopic dermatitis mouse was very effectiveness to the atopy dermatitis treatment.

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부정형 방사선 조사면에 대한 투과선량 보정 알고리즘 (Transmission Dose Estimation Algorithm for Irregularly Shaped Radiation Field)

  • 윤형근;지의규;허순녕;우홍균;이형구;신교철;김시용;하성환
    • Radiation Oncology Journal
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    • 제20권3호
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    • pp.274-282
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    • 2002
  • 목적 : 방사선치료시 환자에 조사되는 방사선량을 매 치료시마다 간편하게 확인하기 위한 생체내(in vivo) 선량측정의 한 방법으로 투과선량을 이용하는 새로운 시스템에 필요한 알고리즘을 이미 개발한 바 있다. 본 연구에서는 조사면 일부가 차폐된 부정형 조사면에서 적용하기 위한 보정 알고리즘을 개발하고자 하였다. 재료 및 방법 : 알고리즘을 개발하기 위한 기본 자료를 마련하기 위하여 투과선량 측정을 시행하였다. 측정에는 선형가속기의 6 MV 및 10 MV의 X선을 이용하였고, 이온함형 측정기 및 전위계를 사용하였다. 측정조건으로는 조사면의 크기(collimator opening)는 $2\times2\;cm^2$에서 $32\times32\;cm^2$까지 한 변을 2 cm씩 증가시켜 16단계로 하였고, 팬톰 두께(phantom thickness; Tp)는 0, 10, 20 및 30 cm, 팬톰과 측정기간의 거리(phantom chamber distance; PCD)는 10, 30 및 50 cm으로 하였다. 이 때 조사면의 일부를 차폐하였으며 차폐되지 않은 유효조사면(effective field size)의 크기를 $5\times5,\;10\times10,\;15\times15$$20\times20\;cm^2$으로 하였다. 결과 : 조사면의 일부가 차폐체에 의하여 차폐된 경우 종양선량이 감소되며 동시에 투과선량도 감소된다는 물리학적인 추론을 이용하여 방사선조사면 일부 차폐가 투과선량에 미치는 영향을 보정하기 위한 알고리즘을 개발하였으며 조사면 일부가 차폐된 여러 측정 조건에서 알고리즘을 이용한 계산치와 실제측정치 간의 오차는 ${\pm}1.0\%$ 이내이었다. 결론 : 투과선량 계산 알고리즘은 조사면 일부가 차폐된 불규칙 조사면의 경우 ${\pm}1.0\%$ 이하의 오차 범위로 정확히 투과선량을 계산할 수 있음을 확인하였다.

로드셀 기반의 실내 위치추적 보완 기법 (Supplementation of the Indoor Location Tracking Techniques Based-on Load-Cells Mechanism)

  • 이남수;문승진
    • 인터넷정보학회논문지
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    • 제17권6호
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    • pp.1-8
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    • 2016
  • 기존의 실내 침입 탐지 및 대상 객체의 이동 경로 추정은 객체가 수신 장치를 갖고 있어야 하는 문제점과 단일 셀(약 $100cm{\times}100cm$)의 공간 내에 객체의 수와 이동 범위를 파악할 수 없는 문제가 지적되어 왔다. 이러한 방법을 해결하기 위해 보편적으로 사용되는 기술인 CCTV를 이용한 방법은 환경적인 변수로 인하여 상당히 제한적일 뿐만 아니라 음영 지역에서(e.g., 상황인식 시스템이 설치되지 않은 곳, 광량이 현저히 낮아 환경의 상황을 파악할 수 없을 경우) 서비스를 받을 수 없다. 이에 본 논문은 센서 네트워크(Sensor Network) 시스템 기반의 객체 탐지 및 대응의 범위 확대가 가능함과 동시에 대상 객체의 이동경로 추적을 능동적으로 대응할 수 있는 실내 보안감시 시스템을 제안한다. 제안된 시스템은 가상의 시나리오에 기반을 두어 구현되었으며, 기존 시설에서 발생할 수 있는 환경적인 단점인 신호의 단절 및 사물의 위치 추정에 대한 손실을 보완하며, 위급한 상황 및 객체에 대한 행동 패턴의 신속한 분석이 가능케 되어, 비상시 사고 예방 및 발생된 상황에 대한 유연한 대처가 가능하리라 사료된다.

라이다 칩을 이용한 고해상도 위성영상의 자동좌표등록 (LiDAR Chip for Automated Geo-referencing of High-Resolution Satellite Imagery)

  • 이창노;오재홍
    • 한국측량학회지
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    • 제32권4_1호
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    • pp.319-326
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    • 2014
  • 고해상도 위성영상을 성공적으로 활용하기 위해서는 지상기준점 등을 활용한 좌표등록 및 보정 과정이 필수적이다. 작업자의 수작업을 통한 기준점 획득의 경우 작업 시간이 오래 걸리므로, 자동화된 좌표 등록 방법에 대한 요구가 증대하고 있다. 보정하고자 하는 위성 영상을 정확한 좌표를 가진 참조 데이터에 영상 매칭을 수행하는 기법이 많이 소개 되었는데, 참조 데이터 중 라이다 데이터의 경우 공간 해상도 및 정확도가 높고 무엇보다 3차원 데이터이기 때문에 기복 변위 등을 내포하고 있지 않는 등의 장점을 보인다. 최근 라이다 데이터와 고해상도 위성영상간의 매칭을 위한 기법이 연구, 발표되었으나, 라이다 데이터의 특성상 대용량이기 때문에 처리에 많은 시간이 소요되는 등의 단점이 있었다. 따라서 본 논문에서는 일부의 공간만을 라이다 칩으로 추출 및 저장하여 위성영상의 좌표 등록에 활용하는 연구를 수행하였다. 이를 위해, 전체 라이다 포인트 데이터를 반사강도 정사영상 및 수치표고모델의 두 가지 형태로 변환하고 에지 추출을 통해 의미 있는 양의 에지 정보만을 포함하는 지역을 영상형태의 라이다 칩으로 추출, 저장하였으며, 용량이 현저히 줄어든 것을 확인할 수 있었다. 마지막으로 라이다 칩을 아리랑2호 및 아리랑3호 영상의 자동 좌표등록에 활용 해본 결과 평균 한 픽셀가량의 정확도 또한 확보할 수 있었다.