• 제목/요약/키워드: reconstructed

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Cone Beam형 CT와 파노라마 영상에서 하악궁의 영상 왜곡 분석 (Analysis of Image Distortion by Mandibular Arch Form in Cone Beam CT and Panoramic Image)

  • 정천수;이기흔
    • 한국방사선학회논문지
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    • 제7권4호
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    • pp.301-305
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    • 2013
  • Cone Beam CT 데이터를 3차원 컴퓨터 프로그램을 이용하여 기존의 파노라마 영상과 재구성된 파노라마 영상을 재현해서 악궁형태에 따른 치아의 왜곡을 분석하고자 하였다. Cone Beam CT의 횡단면 영상과 재구성 파노라마에서 측정된 치아의 직경은 전치부에서 구치부로 갈수록 큰 변화없이 일치되는 것을 알 수 있었다. 하지만 파노라마는 전치부에서 약간의 왜곡이 보이다가 구치부로 갈수록 왜곡이 더 심한 것을 알 수 있었다. 환자 개개인의 악궁에 맞게 재구성된 파노라마가 일반적으로 사용되는 파노라마 촬영보다 왜곡이 더 감소한다는 것을 알 수 있었다. 또한 파노라마는 전치부에서 구치부로 갈수록 왜곡이 더 심해지는 것을 알 수 있었는데, 이 또한 재구성된 파노라마 영상에서는 왜곡이 감소한다는 것을 알 수 있었다.

Diagnosis of Unstained Biological Blood Cells Using a Phase Hologram Displayed by a Phase-only Spatial Light Modulator and Reconstructed by a Fourier Lens

  • Ibrahim, Dahi Ghareab Abdelslam
    • Current Optics and Photonics
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    • 제6권6호
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    • pp.598-607
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    • 2022
  • In this paper, a simple nondestructive technology is used to investigate unstained biological blood cells in three dimensions (3D). The technology employs a reflective phase-only spatial light modulator (SLM) for displaying the phase hologram of the object being tested, and a Fourier lens for its reconstruction. The phase hologram is generated via superposing a digital random phase on the 2D image of the object. The phase hologram is then displayed by the SLM with 256 grayscale levels, and reconstructed by a Fourier lens to present the object in 3D. Since noise is the main problem in this method, the windowed Fourier filtering (WFF) method is applied to suppress the noise of the reconstructed object. The quality of the reconstructed object is refined and the noise level suppressed by approximately 40%. The technique is applied to objects: the National Institute of Standards (NIS) logo, and a film of unstained peripheral blood. Experimental results show that the proposed technique can be used for rapid investigation of unstained biological blood cells in 3D for disease diagnosis. Moreover, it can be used for viewing unstained white blood cells, which is still challenging with an optical microscope, even at large magnification.

3차원 동영상을 구현하기 위한 실시간 홀로그램의 제작 (Fabrication of Real-Time Hologram for the Implementation of 3-D Moving Picture)

  • 배장근;박세준;김수중
    • 전자공학회논문지T
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    • 제36T권1호
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    • pp.25-31
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    • 1999
  • CCD 카메라와 LCD를 사용하여 실시간 홀로그램 제작방법을 제안하였다. 본 시스템은 백색광을 사용하여 3차원 영상을 재생하기 위한 무지개 홀로그램 방법을 사용하였으며, CCD카메라의 낮은 해상도를 감안하여 간섭패턴의 간격을 크게 할 수 있는 in-line 홀로그램 제작방법을 사용하였다. 제안한 구성도로 간섭된 간섭패턴은 CCD카메라에 감지되고 비디오신호로 변환되어 LCD에 입력된다. 간섭패턴이 입력된 LCD에 백색광을 조사하여 영상을 재생하면 입체영상을 볼 수 있으며, 입력영상의 위치를 변화하면 재생영상도 같이 움직이는 실시간 홀로그램이 된다. 본 논문에서 제안된 방법이 백색광을 사용한 실시간 홀로그램 제작에 유용함을 확인하기 위하여 해상도가 높은 홀로그래픽 필름에 먼저 기록하여 재생해보고, 이를 다시 LCD에 기록하고 재생한 후 그 결과를 비교하였다. 또 기록시 기준파와 물체파의 세기비를 변화시켜 최적의 간섭조건을 도출하였다.

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Fascial Free Flap for Reconstruction of the Dorsolateral Hand and Digits: The Advantage of a Thin Contour

  • Lee, Min Gue;Kim, Jin Soo;Lee, Dong Chul;Roh, Si Young;Lee, Kyung Jin;Choi, Byeong Kyoo
    • Archives of Plastic Surgery
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    • 제43권6호
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    • pp.551-558
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    • 2016
  • Background Fascial free flaps have been widely used for reconstruction of the hand because they are thin. However, studies reporting objective data regarding the advantages of this approach are lacking. Thus, we report our experience with such flaps. Methods Forty-five cases of fascial free flaps between November 2006 and March 2014 were reviewed. Nine cases involving reconstructed dorsal or lateral defects were included. Four anterolateral thigh fascial free flaps and 5 lateral arm fascial free flaps were examined. Maximal flap contour was assessed by measuring reconstructed tissue thickness at the central area from the surface of the skin to below the bone in a vertical manner using ultrasonography and X-ray data. Contralateral regions were examined in the same manner and a comparative analysis was performed. A questionnaire survey regarding aesthetic satisfaction was also administered. Results All reconstructed parts had a thicker contour than the contralateral side. The average relative percentage of reconstructed tissue thickness was found to be 152% using ultrasonography and 143% using X-ray imaging. According to the aesthetic satisfaction survey, the average rate of satisfaction for patients was 62%, and satisfaction with the flap contour was 72%. Conclusions Using a fascial free flap, the reconstructed tissue was approximately $1.5{\times}$ as thick as the contour of the normal side, which led to positive responses regarding aesthetic satisfaction.

RGB-D 영상으로 복원한 점 집합을 위한 고화질 텍스쳐 추출 (High-quality Texture Extraction for Point Clouds Reconstructed from RGB-D Images)

  • 서웅;박상욱;임인성
    • 한국컴퓨터그래픽스학회논문지
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    • 제24권3호
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    • pp.61-71
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    • 2018
  • RGB-D 카메라 촬영 영상에 대한 카메라 포즈 추정을 통하여 복원한 3차원 전역 공간의 점 집합으로부터 삼각형 메쉬를 생성할 때, 일반적으로 메쉬의 크기가 커질수록 3차원 모델의 품질 또한 향상된다. 하지만 어떤 한계를 넘어서 삼각형 메쉬의 해상도를 높일 경우, 메모리 요구량의 과도한 증가나 실시간 렌더링 성능저하 문제뿐만 아니라 RGB-D 센서의 정밀도 한계로 인한 접 집합 데이터의 노이즈에 민감해지는 문제가 발생한다. 본 논문에서는 실시간 응용에 적합한 3차원 모델 생성을 위하여 비교적 적은 크기의 삼각형 메쉬에 대하여 3차원 점 집합의 촬영 색상으로부터 고화질의 텍스쳐를 생성하는 기법을 제안한다. 특히 카메라 포즈 추정을 통하여 생성한 3차원 점 집합 공간과 2차원 텍스쳐 공간 간의 매핑 관계를 활용한 간단한 방법을 통하여 RGB-D 카메라 촬영 영상으로부터 복원한 3차원 모델에 대하여 효과적으로 텍스쳐를 생성할 수 있음을 보인다.

The Qualitative Analysis of Single Shot Fast Spin Echo (SSFSE) and Maximum Intensity Projection (MIP) on Magnetic Resonance Cholangiopancreatography

  • Park, Cheol-Soo;Cho, Jae-Hwan;Lee, Hae-Kag;Dong, Kyung-Rae;Chung, Woon-Kwan;Seok, Jong-Min;Han, Man-Seok;Lee, Sun-Yeob;Goo, Eun-Hoe;Kim, Eng-Chan
    • Journal of Magnetics
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    • 제17권2호
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    • pp.138-144
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    • 2012
  • 3-dimensional magnetic resonance cholangiopancreatography (MRCP) images reconstructed using the maximum intensity projection technique were analyzed qualitatively in patients diagnosed with pancreatobiliary diseases to determine their diagnostic utility. Single shot fast spin echo (SSFSE), fast spin echo (FSE) and 3-dimensional reconstructive images were acquired from 20 patients diagnosed histologically with pancreatobiliary diseases using a 3.0T MR scanner. According to qualitative analysis, the fast spin echo images and 3-dimensional reconstructed images of the hepatic duct, gall bladder and common bile duct had a higher signal to noise ratio (SNR) than the single shot fast spin echo images. Fast spin echo images and 3-dimensional reconstructed images did not show any differences. The contrast to noise ratio of the hepatic duct, gallbladder and common bile duct on the fast spin echo images and 3-dimensional reconstructed images was higher than that of the single shot fast spin echo images. The fast spin echo images and 3-dimensional reconstructed images showed similar quality.

혀의 재건을 위한 부피 및 표면적의 측정 (Estimation of Volume and Surface Area for Reconstruction of Tongue)

  • 박하나로;김희진;정우진;안순현
    • 대한두경부종양학회지
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    • 제27권1호
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    • pp.27-31
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    • 2011
  • Purpose : Anterolateral thigh and radial forearm flap is the most important fasciocutaneous flap widely used for reconstruction of tongue. One important purpose of flap is replacing the volume of tongue but still there is no data about the surface area and volume to be reconstructed after glossectomy. In this paper, surface area and volume is estimated from the 3-dimensionally reconstructed MRI images to see which flap is more ideal and to give the reference value for reconstruction. Materials and Methods : With coronal MRI image, tongue including only the intrinsic muscle is delineated in every section and reconstructed 3-dimensionally and calculated the volume and surface area to be reconstructed according to the degree of glossectomy. This volume and surface area was compared with the volume of anterolateral thigh and radial forearm flap. Results : The volume and surface area to be reconstructed in hemiglossectomy was $39.0{\pm}4.0cm^3$ and $31.8{\pm}2.7cm^2$ respectively. The average thickness of anterolateral thigh flap is $9.4{\pm}2.8mm$ and that of radial forearm is $3.8{\pm}1.0mm$. Comparing the curve of tongue surface area and volume with the volume of flap, the anterolateral thigh flap has more ideal volume to replace the defect. Conclusions : The surface area and volume requested for reconstruction could be suggested and the anterolateral thigh flap has more ideal volume for reconstruction of glossectomy defect.

하악 치성점액종 환자에서 유리장골이식으로 재건된 하악골의 골신장술 후 임플란트식립 : 증례보고 (DISTRACTION OSTEOGENESIS FOLLOWED BY IMPLANT INSTALLATION ON THE RECONSTRUCTED MANDIBLE WITH A FREE ILIAC BONE GRAFT IN A ODONTOGENIC MANDIBULAR MYXOMA PATIENT : CASE REPORT)

  • 임헌준;김문섭;이대정;이종복;민승기;편준영
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제31권5호
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    • pp.419-424
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    • 2009
  • Odontogenic myxoma, a rare tumour that occurs in the jaws, locally invasive, destructive tumors that do not metastasize to lymph nodes. Large odontogenic myxoma on mandible is treated by mandibulectomy, defected mandible is reconstructed by bone graft. Reconstructed mandible is difficult to reconstruct dentition using implant because of deficiency of bone amount. So it is necessary to additional bone graft. But a poor aspect of soft tissue lead to unsatisfactory result. Because of distraction osteogenesis is possible to reconstruction of an amount of bone and soft tissue, that is advantage to reconstruction of alveolar bone on reconstructed mandible. We report with review of literatures the 25 years old male patient who had odontogenic myxoma in left mandible, was undergone mandibulectomy and successfully implant installation and prosthetic restoration after distraction osteogenesis(Track $Plus^{(R)}$, KLS Martin, Germany) on the reconstructed mandible with a free iliac bone graft, and we have conservative and successful result.

Effects of in vitro Culture Period of Reconstructed Embryos and Genetic Background of Feeder Cells on Establishment of Embryonic Stem Cells Derived from Somatic Cell Nuclear Transfer Blastocysts in Pigs

  • Han, Na Rae;Baek, Song;Lee, Yongjin;Lee, Joohyeong;Yun, Jung Im;Lee, Eunsong;Lee, Seung Tae
    • 한국동물생명공학회지
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    • 제35권1호
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    • pp.86-93
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    • 2020
  • The establishment of porcine embryonic stem cells (ESCs) from porcine somatic cell nuclear transfer (SCNT) blastocysts is influenced by in vitro culture day of porcine reconstructed embryo and feeder cell type. Therefore, the objective of the present study was to determine the optimal in vitro culture period for reconstructed porcine SCNT embryos and mouse embryonic fibroblast (MEF) feeder cell type for enhancing colony formation efficiency from the inner cell mass (ICM) of porcine SCNT blastocysts and their outgrowth. As the results, porcine SCNT blastocysts produced through in vitro culture of the reconstructed embryos for 8 days showed significantly increased efficiency in the formation of colonies, compared to those for 7 days. Moreover, MEF feeder cells derived from outbred ICR mice showed numerically the highest efficiency of colony formation in blastocysts produced through in vitro culture of porcine SCNT embryos for 8 days and porcine ESCs with typical ESC morphology were maintained more successfully over Passage 2 on outbred ICR mice-derived MEF feeder cells than on MEF feeder cells derived from inbred C57BL/6 and hybrid B6CBAF1 mice. Overall, the harmonization of porcine SCNT blastocysts produced through in vitro culture of the reconstructed embryos for 8 days and MEF feeder cells derived from outbred ICR mice will greatly contribute to the successful establishment of ESCs derived from porcine SCNT blastocysts.

전방십자인대 수술이 시행되어진 슬관절과 정상 슬관절의 유효 모멘트암 (effective moment arm) 비교 분석 (Bilateral Comparison of Effective Moment Arms of the Quadriceps force on Unilateral ACL-Reconstructed Individuals)

  • 채원식
    • 한국운동역학회지
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    • 제13권1호
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    • pp.13-21
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    • 2003
  • The purpose of this study is (a) to estimate effective moment arms of quadriceps forces and (b) to compare the $d_e$ between the ACL-reconstructed and uninjured knees from the same individual. One female (20 yrs old, 2 yrs post-op, hamstring tendon autograft) and two males (22 yrs old, 2 yrs post-op; 28 yrs old, 4 yrs post-op; Patellar tendon autografts for both). Sagittal view radiographs were obtained for 6-7 different angles $(range\;5^{\circ}-110^{\circ})$ from each knee. The do was determined by the method of Chow et al. (1999a). The results showed that the maximum de values ranged from 4.61 to 5.59cm and 4.59 to 4.89cm for the ACL-reconstructed and uninjured knees, respectively. The maximum $d_e$ occurred between $35^{\circ}\;and\;50^{\circ}\;and\;20^{\circ}\;and\;50^{\circ}$ for the ACL-reconstructed and uninjured knees, respectively. The minimum do values ranged from 4.12 to 4.35 cm and 3.12 to 3.63cm for the ACL-reconstructed and uninjured knees, respectively. The effective moment arm of the knee extensor affects the loads on knee ligaments during knee-extension exercises. Because apparent differences in the moment arm of the quadriceps in different participants, it is very important to use personalized knee joint geometry for the computation of knee joint force. In the present study, no noticeable bilateral difference was found in the male subjects. However, apparent bilateral differences in de were observed in the female subject. This suggests that the effects of ACL reconstruction surgery on patellar mechanism deserve further investigation.