• Title/Summary/Keyword: Volume reconstruction

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A One Stage Reconstruction of Defective Type Cleft Earlobe: Infra-auricular Transposition Flap (귓볼 하부 전위피판을 이용한 결손형 선천성 귓볼갈림증의 재건)

  • Jung, Dong Woo;Kang, Dai Hun;Kim, Tae Gon;Lee, Jun Ho;Kim, Yong-Ha
    • Archives of Craniofacial Surgery
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    • v.13 no.2
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    • pp.135-138
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    • 2012
  • Purpose: Reconstruction of the cleft earlobe is challenging. Several procedures are available to reconstruct congenital earlobe deformities. However, for large defective type, surgical procedures and designs are complex and tend to leave a visible scar. We present a simple method of reconstruction for defective type congenital cleft earlobe using a one stage technique with infraauricular transposition flap. This allows for easy and accurate size estimation and good aesthetic outcomes. Methods: A 4-year-old male patient has congenital cleft earlobe and antihelical deformity. Otoplasty for antihelical deformity correction and one stage infra-auricular transposition flap for earlobe reconstruction were performed. The flap was designed from the inferoanterior margin of the earlobe. The size of the flap was determined based on the normal side, and the width and length of the flap was 1 cm and 3 cm in size, respectively. An incision was made at the midline of the defective lobule. Further, the elevated flap was inserted. The elevated flap and the incision margins of the lobule were sutured together. Then, the donor site was closed primarily. Results: The volume and shape of the reconstructed earlobe were natural. There was no flap necrosis. The donor site had no morbidities and scar was not easily notable. Conclusion: Infra-auricular transposition flap can be designed easily and offer sufficient volume of earlobe. Furthermore, the scar is inconspicuous. In conclusion, infra-auricular transposition flap can be a good option for reconstructing a large defect type cleft earlobe.

Superficial Circumflex Iliac Artery Perforator Free Flap for Reconstruction of Small or Medium Sized Defect on Lower Extremities (하지의 작거나 중등도의 결손 부위 재건을 위한 얕은엉덩휘돌이동맥 천공지 유리 피판술)

  • Kim, Kyu Nam;Jeong, Woo Shik;Hong, Joon Pio;Yoon, Chi Seon
    • Archives of Reconstructive Microsurgery
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    • v.22 no.1
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    • pp.18-23
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    • 2013
  • Purpose: For reconstruction of lower extremity defects, various flaps can be used and the appropriate flap must be selected and applied according to the size of the defect. In particular, in cases where the defect size is small to moderate, thinner or smaller volume flaps are useful. The authors performed reconstruction of small to moderate defects on the lower extremities using superficial circumflex iliac artery perforator free flaps and are reporting the results. Materials and Methods: Fifteen patients underwent reconstruction of defects on lower extremity areas using superficial circumflex iliac artery perforator free flaps from July 2011 to July 2012 at this hospital. The flaps were elevated from above the deep fat layer, and, in all cases, the vessel diameter of the flaps was less than 1mm, with the exception of superficial vein that accompanied it. Results: The mean follow up period was 4.46 months, and, despite a partial loss in the flap in two cases, there were no total losses. All donor sites were closed with primary closure, and there was no occurrence of complications, such as hematomas, seromas, or lymphorrheas. The patients were highly satisfied with the donor site scar since it could be masked by underwear. Conclusion: Compared to other flaps, superficial circumflex iliac artery perforator free flaps are thinner in thickness and smaller in volume, which results in a more natural contour of the recipient site after the operation. In addition, since the flap can be elevated from supra-deep fat layer, the operation time can be shortened, and lymphorrhea can be prevented, which in turn lessens donor-site morbidity.

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Effects of Advanced Modeled Iterative Reconstruction on Coronary Artery Calcium (CAC) Scores (ADMIRE가 관상동맥 칼슘(CAC) 점수에 미치는 영향)

  • Lee, Sang-Heon;Lee, Hyo-Young
    • Journal of the Korean Society of Radiology
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    • v.15 no.5
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    • pp.603-612
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    • 2021
  • The effect of Advanced Modeled Iterative Reconstruction (ADMIRE) on the coronary artery calcium (CAC) score of computed tomography was evaluated. Coronary artery calcium images (348 calcium, 6 groups, total of 2088 calcium) were acquired by 128-slice dual-source CT of 89 patients.Volume score and Agatston score were measured from images reconstructed with filtered back projection (FBP) and ADMIRE (1-5). The difference between FBP and ADMIRE Strength (1-5) was confirmed through the Kruskal-Wallis test, and the post-hoc analysis was performed using the Mann-Whitney U test based on FBP. Both volume score and Agatston score showed statistically significant differences between FBP and ADMIRE (1-5) (P=0.015, P=0.0.38). As a result of post hoc analysis, the volume score decreased to 9.5% in ADMIRE 4 (Z=-2.359, P=0.018) and 13.2% in ADMIRE 5 (Z=-3.113, P=0.002) based on FBP. Agatston score decreased to 10.4% in ADMIRE 4 (Z=-2.051, P=0.040) and 14.0% in ADMIRE 5 (Z=-2.718, P=0.007) based on FBP. High ADMIRE strength affected the volume score and Agatston score due to the decrease in calcium area. In addition, the change in the Density factor due to the decrease in Maximum HU may affect the calculation of the Agatston score.

Dynamic Nonlinear Prediction Model of Univariate Hydrologic Time Series Using the Support Vector Machine and State-Space Model (Support Vector Machine과 상태공간모형을 이용한 단변량 수문 시계열의 동역학적 비선형 예측모형)

  • Kwon, Hyun-Han;Moon, Young-Il
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.3B
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    • pp.279-289
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    • 2006
  • The reconstruction of low dimension nonlinear behavior from the hydrologic time series has been an active area of research in the last decade. In this study, we present the applications of a powerful state space reconstruction methodology using the method of Support Vector Machines (SVM) to the Great Salt Lake (GSL) volume. SVMs are machine learning systems that use a hypothesis space of linear functions in a Kernel induced higher dimensional feature space. SVMs are optimized by minimizing a bound on a generalized error (risk) measure, rather than just the mean square error over a training set. The utility of this SVM regression approach is demonstrated through applications to the short term forecasts of the biweekly GSL volume. The SVM based reconstruction is used to develop time series forecasts for multiple lead times ranging from the period of two weeks to several months. The reliability of the algorithm in learning and forecasting the dynamics is tested using split sample sensitivity analyses, with a particular interest in forecasting extreme states. Unlike previously reported methodologies, SVMs are able to extract the dynamics using only a few past observed data points (Support Vectors, SV) out of the training examples. Considering statistical measures, the prediction model based on SVM demonstrated encouraging and promising results in a short-term prediction. Thus, the SVM method presented in this study suggests a competitive methodology for the forecast of hydrologic time series.

Consideration of Standardized Uptake Value (SUV) According to the Change of Volume Size through the Application of Astonish TF Reconstruction Method (Astonish TF 재구성 기법의 적용을 통한 체적 크기의 변화에 따른 표준섭취계수(SUV)에 관한 고찰)

  • Lee, Juyoung;Nam-Kung, Sik;Kim, Ji-Hyeon;Park, Hoon-Hee
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.1
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    • pp.115-121
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    • 2014
  • Purpose: In addition to improving the quality of the PET image, through much research, the development of various programs are performed. Astonish TF reconstruction techniques by Philips can confirm the improved contrast of the lesion. Also, It's image reconstruction of 2 mm is possible with rapid reconstruction rate than conventional. In this study, we compared and evaluated Standardized Uptake Value (SUV) in accordance with the 2 mm reconstruction techniques and traditional 4 mm from the $^{18}F-FDG$ PET whole body image. Materials and Methods: In the phantom experiment, NEMA IEC body phantom (sphere: 10, 13, 17, 22, 28, 37 mm) was used to obtain images by using GEMINI TF 64 PET/CT (Philips, Cleveland, USA). Also, In the clinical images, we performed $^{18}F-FDG$ PET/CT examination to 30 women (age: $55.1{\pm}11.3$, BMI: $24.1{\pm}2.9$) with a diagnosis of breast cancer. After that, we reconstructed images in 2 mm and 4 mm respectively. The region of interest was drawn to acquired images. Since then, we measured SUV and statistically analyzed with SPSS ver.18 by using EBW (Extended Brilliance Workstation) NM ver.1.0. Results: After analyzing the result of the phantom study, there was a tendency that the bigger hot sphere size, the higher SUV. If you compared the 2 mm reconstruction techniques to 4 mm, it increased 95.78% in 10 mm, 50.60% in 13 mm, 25.00% in 17 mm, 30.04% in 22 mm, 31.81% in 28 mm, and 27.84% in 37 mm. Through the result of the analysis of the 2 mm reconstruction techniques and 4 mm in clinical images, it appeared that SUV of 2 mm was higher than that of 4 mm. Also the smaller the volume was, the more the change rate increased. Conclusion: After analyzing the result of the clinical picture and phantom experiments applied by Astonish TF reconstruction techniques, as the size of the volume was small, the change rate of the SUV increased. Therefore, it was necessary to further research about the SUV correction for accurate and active utilization of 2 mm reconstruction techniques which had excellent lesion discrimination ability and contrast in clinic.

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Tomographic reconstruction of Asymmetric Spray by Direct Sampling Method (직접샘플링에 의한 비대칭 분무의 토모그래피 재구성)

  • Lee, C.H.;Won, J.C.
    • Journal of ILASS-Korea
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    • v.7 no.4
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    • pp.9-15
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    • 2002
  • Convolution Fourier transformation tomographically reconstructs the spatially resolved spray injection rate from direct measuring cells. Asymmetric sprays generated from a twin-hole air shroud injector are tested with 12 equiangular projections of measurements. For each projection angle, line of sight integrated injection rate was measured at 35 positions with equal spacing measuring cells of 3 mm in width, 100 mm in length, 55 mm in depth and 0.5 mm thickness of separating wall. Interpolated data between the projection angles effectively increase the number of projections, which significantly enhances the signal-to-noise level in the reconstructed data. This modified convolution Fourier transformation scheme predicts well the structure of asymmetric sprays. Comparative study has been made between sprays with and without air shrouding. Tomograhpic reconstruction of injection rate from direct measuring cells obtained can be used to estimate the accuracy of volume fraction of spray from the LDPA tomographic reconstruction.

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True Three-Dimensional Cone-Beam Reconstruction (TTCR) Algorithm - Transform Method from Parallel-beam (TTR) Algorithm - (원추형 주사 방식의 3차원 영상 재구성(TTCR) 알고리즘 - 평행주사 방식(TTR) 알고리즘의 좌표변환 -)

  • Lee, S.Z.;Ra, J.B.;Cho, Z.H.
    • Proceedings of the KOSOMBE Conference
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    • v.1989 no.05
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    • pp.55-59
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    • 1989
  • A true three-dimensional cone-beam reconstruction (TTCR) algorithm for the complete sphere geometry is derived, which is applicable to the direct volume image reconstruction from 2-D cone-beam projections. The algorithm is based on the modified filtered backprojection technique which uses a set of 2-D space-invariant filters and is derived from the previously developed parallel-beam true three-dimensional reconstruction(TTR) algorithm. The proposed algorithm proved to be superior in spatial resolution compared with the parallel-beam TTR algorithm.

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Reconstruction of Neural Circuits Using Serial Block-Face Scanning Electron Microscopy

  • Kim, Gyu Hyun;Lee, Sang-Hoon;Lee, Kea Joo
    • Applied Microscopy
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    • v.46 no.2
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    • pp.100-104
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    • 2016
  • Electron microscopy is currently the only available technique with a spatial resolution sufficient to identify fine neuronal processes and synaptic structures in densely packed neuropil. For large-scale volume reconstruction of neuronal connectivity, serial block-face scanning electron microscopy allows us to acquire thousands of serial images in an automated fashion and reconstruct neural circuits faster by reducing the alignment task. Here we introduce the whole reconstruction procedure of synaptic network in the rat hippocampal CA1 area and discuss technical issues to be resolved for improving image quality and segmentation. Compared to the serial section transmission electron microscopy, serial block-face scanning electron microscopy produced much reliable three-dimensional data sets and accelerated reconstruction by reducing the need of alignment and distortion adjustment. This approach will generate invaluable information on organizational features of our connectomes as well as diverse neurological disorders caused by synaptic impairments.

Delayed Breast Reconstruction using Free Transverse Rectus Abdominis Myocutaneous(TRAM) Flap; Comparison with Immediate Breast Reconstruction (유리 횡복직근피판술을 이용한 지연 유방재건술; 즉시 유방재건술과의 비교)

  • Jun, Myung-Gon;Ahn, Hee-Chang
    • Archives of Reconstructive Microsurgery
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    • v.10 no.1
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    • pp.28-33
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    • 2001
  • The numbers of breast cancer are increasing in Korea and the needs for breast reconstruction are also parallel with cancer frequency. The purpose of the study is to define the different state and condition between the delayed reconstruction and the immediate reconstruction of breasts and to suggest how to get more satisfactory outcome. The study included 22 patients who underwent delayed breast reconstruction using transverse rectus abdominis myocutaneous(TRAM) free flap from December, 1990 to January, 2001. Their ages ranged from 28 years to 58 years. We have used internal mammary artery and vein as a recipient vessel in 13 patients because of fibrosis and severe scarring in the axillary region and thoracodorsal artery and vein in 9 patients. When we used internal mammary artery with recipient vessel, we would use contralateral deep inferior epigastric artery with donor vessel. We obtained satisfactory result without any flap loss, and most patients satisfied with shape and volume of reconstructed breast. We found that delayed breast reconstruction have some differences compared with immediate breast reconstruction. First, we remove fibrotic and scar tissue as much as possible to achieve satisfactory shape of breast. Second, we plan preoperative design in standing position to obtain symmetrical recreation of inframammary fold. Third, we use internal mammary vessel in many cases with recipient vessel for microvascular anastomosis. Fourth, patients with delayed breast reconstruction feel more satisfaction than patients with immediate breast reconstruction do. Finally, economic burden is much higher in the delayed case than in the immediate case because of no coverage with insurance.

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Mandibular reconstruction with a ready-made type and a custom-made type titanium mesh after mandibular resection in patients with oral cancer

  • Lee, Won-bum;Choi, Won-hyuk;Lee, Hyeong-geun;Choi, Na-rae;Hwang, Dae-seok;Kim, Uk-kyu
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.40
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    • pp.35.1-35.7
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    • 2018
  • Background: After the resection at the mandibular site involving oral cancer, free vascularized fibular graft, a type of vascularized autograft, is often used for the mandibular reconstruction. Titanium mesh (T-mesh) and particulate cancellous bone and marrow (PCBM), however, a type of non-vascularized autograft, can also be used for the reconstruction. With the T-mesh applied even in the chin and angle areas, an aesthetic contour with adequate strength and stable fixation can be achieved, and the pores of the mesh will allow the rapid revascularization of the bone graft site. Especially, this technique does not require microvascular training; as such, the surgery time can be shortened. This advantage allows older patients to undergo the reconstructive surgery. Case presentation: Reported in this article are two cases of mandibular reconstruction using the ready-made type and custom-made type T-mesh, respectively, after mandibular resection. We had operated double blind peer-review process. A 79-year-old female patient visited the authors' clinic with gingival swelling and pain on the left mandibular region. After wide excision and segmental mandibulectomy, a pectoralis major myocutaneous flap was used to cover the intraoral defect. Fourteen months postoperatively, reconstruction using a ready-made type T-mesh (Striker-Leibinger, Freibrug, Germany) and iliac PCBM was done to repair the mandible left body defect. Another 62-year-old female patient visited the authors' clinic with pain on the right mandibular region. After wide excision and segmental mandibulectomy on the mandibular squamous cell carcinoma (SCC), reconstruction was done with a reconstruction plate and a right fibula free flap. Sixteen months postoperatively, reconstruction using a custom-made type T-mesh and iliac PCBM was done to repair the mandibular defect after the failure of the fibula free flap. The CAD-CAM T-mesh was made prior to the operation. Conclusions: In both cases, sufficient new-bone formation was observed in terms of volume and strength. In the CAD-CAM custom-made type T-mesh case, especially, it was much easier to fix screws onto the adjacent mandible, and after the removal of the mesh, the appearance of both patients improved, and the neo-mandibular body showed adequate bony volume for implant or prosthetic restoration.