• ETRI Journal
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• 제27권6호
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• pp.708-712
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• 2005

We propose a computational reconstruction technique in large-depth integral imaging where the elemental images have information of three-dimensional objects through real and virtual image fields. In the proposed technique, we reconstruct full volume information from the elemental images through both real and virtual image fields. Here, we use uniform mappings of elemental images with the size of the lenslet regardless of the distance between the lenslet array and reconstruction image plane. To show the feasibility of the proposed reconstruction technique, we perform preliminary experiments and present experimental results.

• 대한전기학회논문지:전력기술부문A
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• 제48권5호
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• pp.658-663
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• 1999

2D sliced CT images hardly express the human disease in a space. This space expression can be reconstructed into 3D image by piling up the CT sliced image in succession. In medical image, in order to get the reconstructed 3D images, expensive system or much calculation time is needed. But by changing the method of reconstruction procedure and limit the range, the reconstruction time could be reduced. In this study, to reduce the processing time and memory, we suggested a method of interpolation and ray casting processing at the same time in a limited range. Such a limited range processing have advantages that we could reduce the unnecessary interpolation and ray casting. Through a experiment, it is founded that the reconstruction time and the memory was much reduced.

• Archives of Plastic Surgery
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• 제47권6호
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• pp.574-582
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• 2020

Background Several oncoplastic approaches have been implemented in recent years to enhance cosmetic results and to reduce complications. The round block technique is a volume displacement technique for breast reconstruction after breast-conserving surgery (BCS). However, its indications are currently limited according to tumor location, and its cosmetic results and complications have not been clearly established. We hypothesized that the round block technique could produce favorable cosmetic results without major complications regardless of tumor location or nipple-tumor distance, below a certain resected tumor volume and tumor-breast volume ratio. Methods All breast reconstructions using the round block technique after BCS were included in this analysis. Patients' data were reviewed retrospectively to investigate complications during follow-up, and clinical photos were used to evaluate cosmetic results. The relationships of tumor location, nipple-tumor distance, tumor volume, and the tumor-breast volume ratio with cosmetic results were investigated. Results In total, 108 breasts were reconstructed. The mean resected tumor volume was 30.2±15.0 mL. The cosmetic score was 4.5±0.6 out of 5. Tumor location, nipple-tumor distance, tumor volume, tumor-breast volume ratio, radiotherapy, and chemotherapy had no significant effects on cosmetic results or complications. There were no major complications requiring reoperation. Conclusions Breast reconstruction using the round block technique after BCS can lead to good cosmetic results without major complications regardless of the tumor location, nippletumor distance, radiotherapy, or chemotherapy. Below the maximum tumor volume (79.2 mL) and the maximum tumor-breast volume ratio (14%), favorable results were consistently obtained.

• 대한의용생체공학회:의공학회지
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• 제19권2호
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• pp.199-210
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• 1998

본 논문에서는 전산화된 인체 해부도의 필수 기능인 3차원 볼륨 가시화 기법을 제시한다. 오브젝트순서에 기반한 광선 추적과 런-길이 인코딩의 장점을 이용한 이진 볼륨 렌더링 기법은 경계 추출된 칼라 슬라이스로 구성된 볼륨 데이터를 이용하여, 특정 하드웨어의 도움없이 일반 PC에서 대화식 수준의 속도로 3차원 가시화를 수행한다. 이 방법은 이진 볼륨 렌더링을 위해 필요한 이진 깊이 화상의 구성을 간소화하고 새루운 법선 벡터 계산 방법을 적용하여 렌더링 시간의 향상을 꾀하였다. 이와 함께 화질의 손실 없이 관련 데이터의 양을 줄이는 3D경계 인코딩 방법도 제시한다. 본 논문에서 제시한 렌더링 방법의 대화식 수준의 속도와 인코딩 방법의 정보 저장면에서의 효율성은 PC에서 운용될 수 있는 의학 해부도 응용 프로그램의 개발을 보다 가속화할 것이다.

• 대한기계학회논문집B
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• 제36권7호
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• pp.697-703
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• 2012

본 연구에서는 식도 재건 수실 시 유문 성형 여부와 위장 이식편을 이용한 식도 접합 경로에 따른 음식물 역류 현상에 대해 고찰하였다. 위장 이식편의 두 가지 접합 경로(전방, 후방)는 환자 10 명의 CT 영상으로부터 얻어졌으며, 식도관 모델은 RP 로 제작하였다. 식도관은 유문 성형 여부의 두 가지 유문 모델에 연결하였고, 다양한 압력과 펄스폭을 적용하여 역류되는 유체의 체적과 최대 역류 높이를 측정하였다. 그 결과, 역류 체적과 높이는 압력에 따라 증가하였으며, 유문 성형을 하면 전방 경로가 후방 경로보다 역류되는 체적과 높이 작게 나타났다. 역류량은 펄스폭이 증가하면 증가하나 최대 역류높이에 대한 영향은 유문 성형 여부에 따라 달라진다.

• Archives of Plastic Surgery
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• 제46권1호
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• pp.34-38
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• 2019

Background Acellular dermal matrices (ADMs) have recently become widely used in breast reconstruction, but the correlation between the final expander volume and the surface area of the ADM is not well understood. In this study, the expansion of the surface area of ADM and the expander volume was studied retrospectively in cases of acellular dermis-assisted tissue expander breast reconstruction. Methods Twenty cases of immediate breast reconstruction using an ADM-assisted tissue expander from January 2015 to December 2015 were evaluated. In all 20 cases, CGCryoDerm was used as the matrix, with a thickness of 1-3 mm. No slit incisions were made. Finally, the proportional increase in the area of the fully expanded ADM was compared to that of the tissue expander volume. Results The proportional increase in the ADM surface area was calculated to be from 1.1 to 2.46, with a mean value of 1.7. Additionally, under the assumption that the expander had a spherical shape, the increase in its radius (the cube root of its volume) was assessed. The range of the proportional increase in the expander radius was 1.1 to 2.24, with a mean value of 1.66. The proportional increase in the radius of the expanded ADM surface area ranged from 1.04 to 1.34, with a mean ratio of 1.28. Conclusions The results of this study confirmed that the ADM expanded when the tissue expander was inflated. However, the ADM expanded to a lesser extent than the tissue expander, indicating that the muscle and other tissues expanded more than the ADM when the tissue expander was inflated.

• Archives of Plastic Surgery
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• 제45권5호
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• pp.432-440
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• 2018

Background Adjuvant therapy after breast surgery, including tamoxifen or aromatase inhibitors, improves the postoperative outcomes and long-term survival of breast cancer patients. The aim of this study was to determine whether volume changes occurred in the contralateral breast during hormonal or other adjuvant therapies. Methods This study reviewed 90 patients who underwent unilateral breast reconstruction between September 2012 and April 2018 using tissue expanders and a permanent implant after the surgical removal of breast cancer. The volume of the contralateral breast was measured using a cast before the first (tissue expander insertion) and second (permanent implant change) stages of surgery. Changes in breast volume were evaluated to determine whether adjuvant therapy such as hormonal therapy, chemotherapy, and radiation therapy influenced the volume of the contralateral breast. Results The group receiving tamoxifen therapy demonstrated a significant decrease in volume compared with the group without tamoxifen (-7.8% vs. 1.0%; P=0.028). The aromatase inhibitor-treated group showed a significant increase in volume compared with those who did not receive therapy (-6.2% vs. 4.5%; P=0.023). There were no significant differences between groups treated with other hormonal therapy, chemotherapy, or radiation therapy. Conclusions Patients who received tamoxifen therapy showed a significant decrease in volume in the contralateral breast, while no significant change in weight or body mass index was found. Our findings suggest that we should choose smaller implants for premenopausal patients, who have a high likelihood of receiving tamoxifen therapy.

• Archives of Plastic Surgery
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• 제43권5호
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• pp.430-437
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• 2016

Background Accurate breast volume assessment is a prerequisite to preoperative planning, as well as intraoperative decision making in breast reconstruction surgery. The use of three-dimensional surface imaging (3D scanning) to assess breast volume has many advantages. However, before employing 3D scanning in the field, the tool's validity should be demonstrated. The purpose of this study was to confirm the validity of 3D-scanning technology for evaluating breast volume. Methods We reviewed the charts of 25 patients who underwent breast reconstruction surgery immediately after total mastectomy. Breast volumes using the Axis Three 3D scanner, water-displacement technique, and magnetic resonance imaging (MRI) were obtained bilaterally in the preoperative period. During the operation, the tissue removed during total mastectomy was weighed and the specimen volume was calculated from the weight. Then, we compared the volume obtained from 3D scanning with those obtained using the water-displacement technique, MRI, and the calculated volume of the tissue removed. Results The intraclass correlation coefficient (ICC) of breast volumes obtained from 3D scanning, as compared to the volumes obtained using the water-displacement technique and specimen weight, demonstrated excellent reliability. The ICC of breast volumes obtained using 3D scanning, as compared to those obtained by MRI, demonstrated substantial reliability. Passing-Bablok regression showed agreement between 3D scanning and the water-displacement technique, and showed a linear association of 3D scanning with MRI and specimen volume, respectively. Conclusions When compared with the classical water-displacement technique and MRI-based volumetry, 3D scanning showed significant reliability and a linear association with the other two methods.

• Archives of Plastic Surgery
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• 제36권1호
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• pp.75-79
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• 2009

Purpose: The transverse rectus abdominis musculocutaneous(TRAM) flap is the most commonly used autogenous tissue flap for breast reconstruction. Postoperatively, partial flap loss or fat necrosis are relatively common and it may result in a smaller breast volume with marked contour irregularities. These defects are not easy to reconstruct with local tissue rearrangement or with breast implants. The current authors present the results of 2 patients who underwent Latissimus dorsi(LD) flap reconstruction to correct partial flap or fat necrosis that developed after TRAM flap breast reconstruction. Method: Case1: A 50 - year - old woman with left breast cancer visited for breast reconstruction after radical mastectomy. Initially, breast reconstruction with pedicled TRAM was performed. Postoperatively partial flap necrosis was developed. Secondary breast reconstruction using LD flap was done. Case2: A 51 - year - old woman with left breast cancer visited for breast reconstruction after radical mastectomy. Initially, breast reconstruction with pedicled TRAM was performed. Postoperatively fat necrosis was developed. Secondary breast reconstruction using LD flap was done. Results: Secondary breast reconstruction using LD flap survived completely and produce successful reconstruction. There was no significant complication in both patients. Conclusion: LD flap provides sufficient, vascularized skin and soft tissue. The flap can be molded easily to replace deficient tissue in all areas of the breast. These attributes make it an ideal candidate for salvage of the partially failed TRAM flap breast reconstructio.

• 대한두개안면성형외과학회지
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• 제13권2호
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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.