• 제목/요약/키워드: statistical reconstruction

검색결과 208건 처리시간 0.028초

Evaluation of the Accuracy of Distance Measurements on 3D Volume-rendered Image of Human Skull Using Multi-detector CT: Effects of Acquisition Section Thickness and Reconstruction Section Thickness

  • Haijo Jung;Kim, Hee-Joung;Lee, Sang-Ho;Kim, Dong-Wook;Soonil Hong;Kim, Dong-Hyeon;Son, Hye-Kyung;Wonsuk Kang;Kim, Kee-Deog
    • 한국의학물리학회:학술대회논문집
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    • 한국의학물리학회 2002년도 Proceedings
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    • pp.457-460
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    • 2002
  • The image quality of three-dimensional (3D) images has been widely investigated by the qualitative analysis method. A need remains for an objective and quantitative method to assess the image quality of 3D volume-rendered images. The purpose of this study was to evaluate the quantitative accuracy of distance measurements on 3D volume-rendered images of a dry human skull by using multi-detector computed tomography (MDCT). A radiologist measured five times the twenty-one direct measurement line items composed among twelve reference points on the skull surface with a digital vernier caliper. The water filled skull specimen was scanned with a MDCT according to the section thicknesses of 1.25, 2.50, 3.75, and 5.00 mm for helical (high quality; pitch 3:1) scan mode. MDCT data were reconstructed with its acquisition section thickness and with 1.25 mm section thickness for all scans. An observer also measured seven times the corresponding items on 3D volume-rendered images with measuring tools provided by volumetric analysis software. The quantitative accuracy of distance measurements on the 3D volume-rendered images was statistically evaluated (p-value < 0.05) by comparatively analyzing these measurements with the direct distance measurements. The accuracy of distance measurements on the 3D volume-rendered MDCT images acquired with 1.25, 2.50, 3,75 and 5.00 mm section thickness and reconstructed with its section thickness were 48%, 33%, 23%, and 14%, respectively. Meanwhile, there were insignificant statistical differences in accuracy of distance measurements among 3D volume-rendered images reconstructed with 1.25 mm section thickness for the each acquisition section thickness. MDCT images acquired with thick section thickness and reconstructed with thin section thickness in helical scan mode should be effectively used in medical planning of 3D volume-rendered images. The quantitative analysis of distance measurement may be a useful tool for evaluating the quantitative accuracy and the defining optimal parameters of 3D volume-rendered CT images.

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유방절제술 환자의 신체상, 자아존중감과 건강증진행위의 관계 (Relationships among Body Image, Self-esteem and Health Promotion Behavior in Mastectomy Patients)

  • 정경숙;박금자
    • 종양간호연구
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    • 제7권1호
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    • pp.36-46
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    • 2007
  • Purpose: This study was designed to fine out the relationships among body image, self-esteem and health promotion behavior in mastectomy patients. Method: Data were obtained by self -reported questionnaires from 218 patients undergone mastectomy from September 1 to October 15, 2005. And data were analyzed using SPSS/PC WIN 12.0 program. For the statistical analysis of the date, frequency and percentage, mean and standard deviation, t-test, ANOVA and Scheffe test and Pearson's correlation coefficients were used. Result: The mean scores of the body image, self-esteem, and health promotion of the subjects were $41{\pm}7.40$ (range of scale : 17 to 68), $22.22{\pm}4.95$ range of scale : 10 to 40), and $130.45{\pm}23.99$ range of scale : 50 to 200), respectively. There were significant differences with the score of body image by the work type (F=4.018, p= .008), a number of child (F=3.069, p= .029), and participation with self help group program (t=68.177, p= .001). There were significant differences with the score of self-esteem by the type of religion (F=4.546, p= .002), work type (F=4.488, p= .004), post operation period (F=2.814, p= .026), and participation with self help group program (t=12.901, p= .001). There were significant differences with the score of the health promotion behavior by the type of religion (F=3.066, p= .018), economic state (F=11.765, p= .001), level of education (F=6.285, p= .001), operation site (F=.368, p=.027), family history (t=6.557, p= .011), and hope of breast reconstruction (t=7.025, p=.009). Relationship between body image and self-esteem showed moderate positive correlation (r=0.631, p= .001). The relationship between body image and health promotion behavior showed slightly positive correlation (r=0.257, p= .001). The relationship between self-esteem and health promotion behavior showed moderate positive correlation (r=0.431, p=.001). Conclusion: For the increasement of the health promotion behavior, it is needed to improve body image and self-esteem in mastectomy patients. And, It is needed to encourage to participate with self help group program in mastectomy patients.

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3차원 전산화단층촬영 영상을 이용한 안면 연조직 두께 계측의 임상적 유용성 (Clinical usefulness of facial soft tissues thickness measurement using 3D computed tomographic images)

  • 정호걸;김기덕;한승호;허경석;이제범;박혁;최성호;김종관;박창서
    • Imaging Science in Dentistry
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    • 제36권2호
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    • pp.89-94
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    • 2006
  • Purpose : To evaluate clinical usefulness of facial soft tissue thickness measurement using 3D computed tomographic images. Materials and Methods : One cadaver that had sound facial soft tissues was chosen for the study. The cadaver was scanned with a Helical CT under following scanning protocols about slice thickness and table speed; 3 mm and 3 mm/sec, 5 mm and 5 mm/sec, 7 mm and 7 mm/sec. The acquired data were reconstructed 1.5, 2.5, 3.5 mm reconstruction interval respectively and the images were transferred to a personal computer. Using a program developed to measure facial soft tissue thickness in 3D image, the facial soft tissue thickness was measured. After the ten-time repeation of the measurement for ten times, repeated measure analysis of variance (ANOVA) was adopted to compare and analyze the measurements using the three scanning protocols. Comparison according to the areas was analyzed by Mann-Whitney test. Results : There were no statistically significant intraobserver differences in the measurements of the facial soft tissue thickness using the three scanning protocols (p>0.05). There were no statistically significant differences between measurements in the 3 mm slice thickness and those in the 5 mm, 7 mm slice thickness (p>0.05). There were statistical differences in the 14 of the total 30 measured points in the 5 mm slice thickness and 22 in the 7 mm slice thickness. Conclusion : The facial soft tissue thickness measurement using 3D images of 7 mm slice thickness is acceptable clinically, but those of 5 mm slice thickness is recommended for the more accurate measurement.

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Determinants for further wishes for cosmetic and reconstructive interventions in 1652 patients with surgical treated carcinomas of the oral cavity

  • Holtmann, Henrik;Spalthoff, Simon;Gellrich, Nils-Claudius;Handschel, Jorg;Lommen, Julian;Kubler, Norbert R.;Kruskemper, Gertrud;Rana, Majeed;Sander, Karoline
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제39권
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    • pp.26.1-26.10
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    • 2017
  • Background: The impairment of the appearance is a major problem for patients with carcinomas of the oral cavity. These patients want to recover their preoperative facial appearance. Some do not realize that this is not always possible and hence develop a desire for further cosmetic and reconstructive surgery (CRS) which often causes psychological problems. Method: The desire of patients for CRS (N = 410; 26%) has been acquired in this $D{\ddot{O}}SAK$ rehab study including multiple reasons such as medical, functional, aesthetic and psychosocial aspects. They relate to the parameters of diagnosis, treatment and postoperative rehabilitation. Patients without the wish for CRS (N = 1155; 74%) served as control group. For the surgeons, knowledge of the patient's views is relevant in the wish for CRS. Nevertheless, it has hardly been investigated for patients postoperatively to complete resection of oral cancer. In this retrospective cross-sectional study, questionnaires with 147 variables were completed during control appointments. Thirty-eight departments of Oral and Maxillofacial Surgery took part, and 1652 German patients at least 6 months after complete cancer resection answered the questions. Additionally, a physician's questionnaire (N = 1489) was available. Statistical analysis was performed with SPSS vers. 22. Results: The patient's assessment of their appearance and scarring are the most important criteria resulting in wishes for CRS. Furthermore, functional limitations such as eating/swallowing, pain of the facial muscles, numb regions in the operating field, dealing with the social environment, return to work, tumour size and location, removal and reconstruction are closely related. Conclusion: The wish for CRS depends on diverse functional psychosocial and psychological parameters. Hence, it has to be issued during conversation to improve rehabilitation. A decision on the medical treatment can be of greater satisfaction if the surgeon knows the patients' needs and is able to compare them with the medical capabilities. The informed consent between doctor and patient in regard to these findings is necessary.

전방 십자 인대 봉합술의 수술적 치료 - 최소 4년 이상 추시 결과 - (Surgical Outcome of Primary Repair in Anterior Cruciate Ligament Rupture - Minimum 4-years follow-up -)

  • 변기용;이광진;이석준
    • 대한관절경학회지
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    • 제4권2호
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    • pp.123-127
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    • 2000
  • 목적 : 전방 십자 인대 파열 후 일차적 봉합술을 이용한 수술적 치료 결과에 대해서 알아 보고자 하였다. 대상 및 방법 : 전방 십자 인대 봉합수술을 받았던 25례를 대상으로 IKDC 평가표와 Lysholm score를 이용한 임상적 결과 및 KT-2000 arthrometer를 이용한 이완도를 평가하였다. 대상환자 중 18례에서는 pull-out suture를 시행하였으며, 7례에서는 박근 및 반건양근을 이용한 인대 강화술을 시행하였다. 결과 : IKDC 분석 결과, 전체 환자중 3례에서 A군으로, 13례에서 B군으로, 9례에서 C군으로 평가되었다. Lysholm score는 평균 83점이었다. KT-2000 arthrometer를 이용한 인대 이완도 평가에서는 20lb에서 평균 전방 전위는 3.89mm이었으며, 30lb에서는 평균 7.3mm의 전방 전위를 보였다. 건측 무릎과 환측 무릎의 평균 전방전위도 차이는 20lb에서 1.09mm이었으며, 30lb에서 2.29mm이었고 건측과 환측의 차이는 통계학적으로 유의한 차이가 있었다. 결론 : 봉합술을 시행한 환자에 있어 IKDC라 Lysholm score는 재건술을 시행한 후 평가한 여타 보고에서의 결과보다 만족스럽지 못하며, KT-2000 arthrometer를 이용한 이완도 평가에서도 건측 무릎에 비해 많은 전방 전위를 보였던 바, 특히 젊고 활동성이 많은 환자에 있어서 인대 봉합술 보다는 재건술을 시행하는 것이 좋을것으로 사료 된다.

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탈레반의 아프가니스탄 장악에 따른 국내 테러 발생 가능성 분석 (A Possibility Analysis of Domestic Terrorism in South Korea by Focusing on Afghanistan under the Taliban Forces)

  • 오한길;안계원;배병걸
    • 한국재난정보학회 논문집
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    • 제17권4호
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    • pp.848-863
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    • 2021
  • 연구목적: 2021년 8월 16일 탈레반은 국제테러조직간 공고한 동맹관계를 이용하여, 아프가니스탄 수도 카불을 점령한 뒤 탈레반 정권을 수립하였다. 탈레반은 대한민국 국민을 대상으로, 2004년 김선일 피랍, 2007년 샘물교회 교인 피랍, 2009년 지역재건팀에 대한 공격하는 등 테러를 자행하였으며, 2021 대한민국 아프간 난민 구출 작전에 대해서는 적대감을 가지고 있다. 따라서 본 고에서는 탈레반에 의한 대한민국 테러 발생 가능성을 살펴보고자 한다. 연구방법: 샘물교회 피랍사건으로 국내에도 잘 알려진 탈레반의 전술, 전략, 공격무기 등 다양한 테러활동을 살펴보고, 아프가니스탄에서 발생한 테러 통계 데이터를 기반으로 국내에서 발생 가능한 테러유형과 테러대상시설을 분석하였다. 연구결과: 탈레반은 아프간 정부를 주요 공격대상으로 하고 있으며, IS와 탈레반은 테러대상 선정에 있어 차이를 보인다. 결론: 아프간을 장악한 탈레반과 전 세계 테러리즘 네트워크를 구축한 IS가 협력하여, 국내 다중이용시설을 대상으로 폭탄테러의 위협을 가한다면, 대한민국은 대테러 관련 미흡한 자원과 대책으로 테러 위기에 직면할 수 있다.

PET-CT Normalization, Well Counter Correction에 따른 팬텀을 이용한 영상 평가 (Evaluation of Image for Phantom according to Normalization, Well Counter Correction in PET-CT)

  • 이충운;유연욱;문종운;김윤철
    • 핵의학기술
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    • 제27권1호
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    • pp.47-54
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    • 2023
  • Purpose PET-CT imaging require an appropriate quality assurance system to achieve high efficiency and reliability. Quality control is essential for improving the quality of care and patient safety. Currently, there are performance evaluation methods of UN2-1994 and UN2-2001 proposed by NEMA and IEC for PET-CT image evaluation. In this study, we compare phantom images with the same experiments before and after PET-CT 3D normalization and well counter correction and evaluate the usefulness of quality control. Materials and methods Discovery 690 (General Electric Healthcare, USA) PET-CT equiptment was used to perform 3D normalization and well counter correction as recommended by GE Healthcare. Based on the recovery coefficients for the six spheres of the NEMA IEC Body Phantom recommended by the EARL. 20kBq/㎖ of 18F was injected into the sphere of the phantom and 2kBq/㎖ of 18F was injected into the body of phantom. PET-CT scan was performed with a radioacitivity ratio of 10:1. Images were reconstructed by appliying TOF+PSF+TOF, OSEM+PSF, OSEM and Gaussian filter 4.0, 4.5, 5.0, 5.5, 6.0, 6,5 mm with matrix size 128×128, slice thickness 3.75 mm, iteration 2, subset 16 conditions. The PET image was attenuation corrected using the CT images and analyzed using software program AW 4.7 (General Electric Healthcare, USA). The ROI was set to fit 6 spheres in the CT image, RC (Recovery Coefficient) was measured after fusion of PET and CT. Statistical analysis was performed wilcoxon signed rank test using R. Results Overall, after the quality control items were performed, the recovery coefficient of the phantom image increased and measured. Recovery coefficient according to the image reconstruction increased in the order TOF+PSF, TOF, OSEM+PSF, before and after quality control, RCmax increased by OSEM 0.13, OSEM+PSF 0.16, TOF 0.16, TOF+PSF 0.15 and RCmean increased by OSEM 0.09, OSEM+PSF 0.09, TOF 0.106, TOF+PSF 0.10. Both groups showed a statistically significant difference in Wilcoxon signed rank test results (P value<0.001). Conclusion PET-CT system require quality assurance to achieve high efficiency and reliability. Standardized intervals and procedures should be followed for quality control. We hope that this study will be a good opportunity to think about the importance of quality control in PET-CT

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Evaluation of the correlation between the muscle fat ratio of pork belly and pork shoulder butt using computed tomography scan

  • Sheena Kim;Jeongin Choi;Eun Sol Kim;Gi Beom Keum;Hyunok Doo;Jinok Kwak;Sumin Ryu;Yejin Choi;Sriniwas Pandey;Na Rae Lee;Juyoun Kang;Yujung Lee;Dongjun Kim;Kuk-Hwan Seol;Sun Moon Kang;In-Seon Bae;Soo-Hyun Cho;Hyo Jung Kwon;Samooel Jung;Youngwon Lee;Hyeun Bum Kim
    • 농업과학연구
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    • 제50권4호
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    • pp.809-815
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    • 2023
  • This study was conducted to find out the correlation between meat quality and muscle fat ratio in pork part meat (pork belly and shoulder butt) using CT (computed tomography) imaging technique. After 24 hours from slaughter, pork loin and belly were individually prepared from the left semiconductors of 26 pigs for CT measurement. The image obtained from CT scans was checked through the picture archiving and communications system (PACS). The volume of muscle and fat in the pork belly and shoulder butt of cross-sectional images taken by CT was estimated using Vitrea workstation version 7. This assemblage was further processed through Vitrea post-processing software to automatically calculate the volumes (Fig. 1). The volumes were measured in milliliters (mL). In addition to volume calculation, a three-dimensional reconstruction of the organ under consideration was generated. Pearson's correlation coefficient was analyzed to evaluate the relationship by region (pork belly, pork shoulder butt), and statistical processing was performed using GraphPad Prism 8. The muscle-fat ratios of pork belly taken by CT was 1 : 0.86, while that of pork shoulder butt was 1 : 0.37. As a result of CT analysis of the correlation coefficient between pork belly and shoulder butt compared to the muscle-fat ratio, the correlation coefficient was 0.5679 (R2 = 0.3295, p < 0.01). CT imaging provided very good estimates of muscle contents in cuts and in the whole carcass.

Morbidity and Mortality After Laparoscopy-Assisted Distal Gastrectomy and Totally Laparoscopic Distal Gastrectomy to Treat Gastric Cancer: An Interim Report: A Phase III Multicenter, Prospective, Randomized Trial (The KLASS-07 Trial)

  • Han Hong Lee;Chang Min Lee;Moon-Soo Lee ;In Ho Jeong;Myoung Won Son;Chang Hyun Kim;Moon-Won Yoo;Sung Jin Oh;Young-Gil Son;Sung Il Choi;Mi Ran Jung;Sang Hyuk Seo;Shin-Hoo Park;Seong Ho Hwang;Jae-Seok Min;Sungsoo Park
    • Journal of Gastric Cancer
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    • 제24권3호
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    • pp.257-266
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    • 2024
  • Purpose: We conducted a randomized prospective trial (KLASS-07 trial) to compare laparoscopy-assisted distal gastrectomy (LADG) and totally laparoscopic distal gastrectomy (TLDG) for gastric cancer. In this interim report, we describe short-term results in terms of morbidity and mortality. Methods and Methods: The sample size was 442 participants. At the time of the interim analysis, 314 patients were enrolled and randomized. After excluding patients who did not undergo planned surgeries, we performed a modified per-protocol analysis of 151 and 145 patients in the LADG and TLDG groups, respectively. Results: The baseline characteristics, including comorbidity status, did not differ between the LADG and TLDG groups. Blood loss was somewhat higher in the LADG group, but statistical significance was not attained (76.76±72.63 vs. 62.91±65.68 mL; P=0.087). Neither the required transfusion level nor the operation or reconstruction time differed between the 2 groups. The mini-laparotomy incision in the LADG group was significantly longer than the extended umbilical incision required for specimen removal in the TLDG group (4.79±0.82 vs. 3.89±0.83 cm; P<0.001). There were no between-group differences in the time to solid food intake, hospital stay, pain score, or complications within 30 days postoperatively. No mortality was observed in either group. Conclusions: Short-term morbidity and mortality rates did not differ between the LADG and TLDG groups. The KLASS-07 trial is currently underway.

ASIR를 이용한 두부 CT의 영상 잡음 평가 및 피폭선량 분석 (Evaluation of Image Noise and Radiation Dose Analysis In Brain CT Using ASIR(Adaptive Statistical Iterative Reconstruction))

  • 장현철;김경근;조재환;서정민;이행기
    • 한국방사선학회논문지
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    • 제6권5호
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    • pp.357-363
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    • 2012
  • 본 연구는 두부 컴퓨터 단층 촬영 검사 시 적응식 통계적 반복 재구성법인 알고리즘을 적용하여 노이즈 및 화질평가, 피폭선량의 감소에 대하여 알아보고자 하였다. 두부 CT 검사 시 ASIR를 적용하지 않은 군[A군], ASIR 50 % 적용한군 [B군]으로 나누어 검사하였다. 팬텀연구에서 측정된 CT 노이즈 평균값의 측정결과는 B군이 A군보다 중심부(A)와 주변부(B, C, D)에서 각 각 46.9 %, 48.2 %, 43.2 %, 47.9 %가 감소되었다. 영상화질 평가에서 정량적 분석방법으로 CT 값(number)을 측정하여 잡음(noise) 정도를 분석하였다. 영상 잡음은 A군과 B군 사이에는 통계적으로 유의한 차이가 있었으며, A군이 B군보다 영상 잡음이 유의하게 높았다(group A ;우엽에서 31.87 HU, 좌엽에서 31.78 HU, group B ; 우엽에서 26.6 HU, 좌엽에서 30.42 HU : P<0.05). 영상의 정성적 평가방법으로 두부 임상 영상 평가표에 의해 평가한 결과 80점 만점에 A군의 관찰자 1의 점수는 73.17 점, 관찰자 2의 점수는 74.2 점으로 평가하였으며, B군의 관찰자 1의 점수는 71.77 점, 관찰자 2의 점수는 72.47 점으로 평가하였다. 통계적으로 유의한 차이가 없었으며(P>0.05), 진단에 적절한 영상을 보였다. 피폭선량은 ASIR 50 % 적용하여 검사함으로써 영상의 질적 저하 없이 방사선 피폭선량을 47.6 % 감소 시킬수 있었다. 결론적으로 임상 부위에 ASIR가 적용이 된다면 훨씬 더 적은 선량으로도 검사가 가능할 것으로 사료되며, 검사 시에 검사자가 판단하는데 있어 긍정적인 요인이 될 것으로 사료된다.