• Title/Summary/Keyword: reconstruction

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Measurement of the Mucosal Surface Distance in the Early Gastric Cancer Using CT Gastrography (조기 위암에서 CT Gastrography를 이용한 위점막 표면 거리 측정)

  • Choi, Hyang-Hee;Yu, Wan-Sik;Ryeom, Hun-Kyu;Lee, Jae-Hyuk;Choi, Jae-Jeong;Kim, Hee-Su;Cleary, Kevin;Mun, Seong-Ki;Chung, Ho-Young
    • Journal of Gastric Cancer
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    • v.6 no.3
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    • pp.161-166
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    • 2006
  • Purpose: Recently, the incidence of early gastric cancer (EGC) patients is rapidly increased in Korea. However, they're often not perceptible by surgical palpation or inspection. The aim of this study is 1) to develope a software that can locate the tumor and measure the mucosal distance from an anatomic landmark to the tumor using CT gastrography and 2) to compare the distance measured by the developed software with the distance measured by the pathologic findings. Materials and Methods: Between January 2004 and September 2005, sixty patients (male=45, female=15, mean 57.8 years old) estimated for EGC with preoperative CT scans and undergone gastrectomies in Kyungpook National University Hospital were enrolled in this study. Preoperative CT scans were performed after insufflations of room air via 5 Fr NG tube. The scans included the following parameters: (slice thickness/reconstruction interval: 0.625 mm, kVp: 120, mAs: 200). 3D volume rendering and measurement of the surface distance from the pylorus to the EGC were performed using the developed software. Results: The average difference between the lesion to pylorus distances measured from pathologic specimens and CT gastrography was $5.3{\pm}2.9\;mm(range,\;0{\sim}23\;mm)$. The lesion to pylorus distance measured from CT gastrography was well correlated with that measured from the pathologic specimens (r=0.9843, P<0.001). Conclusion: These results suggest that the surface distance from an anatomic landmark to the EGC can be measured accurately by CT gastrography. This technique could be used for preoperative localization of early gastric carcinomas to determine the optimal extent of surgical resection.

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Evaluation of Different Methods of Gastroenterostomy after Distal Gastrectomy for Gastric Carcinoma (위선암 환자의 원위부 위절제 후 위공장문합의 방법의 선택에 따른 임상 양상의 차이에 관한 고찰)

  • Choi, Eun-Hye;Lee, Jong-Myeong
    • Journal of Gastric Cancer
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    • v.9 no.4
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    • pp.215-222
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    • 2009
  • Purpose: Billroth II gastroenterostomy is a typical reconstruction method after distal gastrectomy for gastric carcinoma, but it has problems, especially frequent reflux esophagitis. Various methods have been tried to address this problem. Among them are Braun enteroenterostomy and Roux-en-Y gastroenterostomy, which are performed separately according to the size of the gastric remnant. The aim of our study was to determine whether these applications are compatible. Materials and Methods: Between September 2003 and April 2007, we performed Roux-en-Y gastroenterostomy operations (14 patients) when the size of the gastric remnant was <10%, Braun enteroenterostomy (17 patients) when the size was between 10 and 20%, and Billroth II gastroenterostomy (14 patients) when the size was between 20 and 40% after subtotal gastrectomy for gastric cancer by a single surgeon at our hospital. We analyzed the results of each treatment. We evaluated the symptoms and endoscopic findings using questionnaires and hospital records. To evaluate nutritional states, we reviewed albumin and hemoglobin levels and body weight changes. Results: All operations were performed safely mortality was 0% and postoperative complications were 8.9%. On endoscopy, reflux gastritis was observed to occur in 7.63%, 18.65% and 40.0%, respectively, of patients who had undergone Roux-en-Y, Braun and Billroth II operations (P=0.13). Reflux esophagitis was observed in 1 patient in the Roux-en-Y group and 1 patient in the Braun group. Endoscopic gastrostasis was observed in 2 patients in the Roux-en-Y group, one of which was thought to cause reflux esophagitis. Patients in the Roux-en-Y group and Braun groups ingested a lower volume of food than did those in the Billroth II group (respectively, 7.1%, 0.0% and 28.7%) and complained less of postprandial discomforts (respectively, 14.3%, 23.5% and 57.1%) and reflux symptoms (respectively 0.0%, 11.8% and 42.9%). Conclusion: The application of Braun enteroenterostomy and Roux-en-Y gastroenterostomy to the small gastric remnant may be effective for reducing reflux symptoms and abdominal discomfort after distal gastric resection. We recommend Roux-en-Y gastroenterostomy when the size of the gastric remnant is <10%, and Braun anastomosis in the others. It will need to be determined which reconstructive procedure is better for many different conditions.

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An Analytical Study of the Problems Involved in the Project to Rehabilitate the Illegal Field Burning Cultivators in Gangweon Do (강원도(江原道) 화전정리사업(火田整理事業)에 수반(隨伴)되는 문제점분석(問題點分析)에 관(關)한 연구(硏究))

  • Ho, Ul Yung
    • Journal of Korean Society of Forest Science
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    • v.28 no.1
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    • pp.50-66
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    • 1975
  • Since it is an undeniable fact that the so-called illegal field-burning cultivation is directly implicated in the causes of forest devastation, land erosion, and drought and flood, thus, barring the nation from a well-balanced economic growth, the policy to exterminate its practices must have the topmost priority. Eighty percent of Gangweon-do is mountain forests and naturally of all others this province has the largest area of illegally burned hill-side farminglands, stubbornly retarding the provincial development policy as well as directly causing tremendous forest damages. In 1965 a 7-year plan mapped out to rehabilitate these gypsy type field burning farmers only to be suspended in 1968 to give way to the mandatory project of clearing the isolated farmsteads set in deep mountain to circumvent the guerilla forces signaled by the so-called Samcheok-Uljin area infiltration. In the meantime, new hordes of roving farmers burned the forests, working a renewed havoc. To cope with this situation, the provincial government, taking the year 1973 as a planning year, launched another three year project (1974-76) and has been enforcing the rehabilitation project mobilizing the whole administrative power. Whether or not this project will succeed solely depends upon whether the forcedly rehabilitated roving farmers can really establish self-supporting homesteads. Among the various difficulties facing the newly established homesteaders are: (1) First of all, the homesteaders must be given money-earning jobs. (2) Financial supports or subsidies must be provided them with which to establish self-supporting homesteads. (3) Private enterprises as well as public organizations must offer them jobs with priority. (4) The rehabilitated rovers themselves must establish self-supporting homesteads before expecting the external assistance. (5) The rehabilitated rovers themselves must have the spirit of self-help, welcoming all levels and all kinds of jobs. (6) The rural revitalization movement must expand the self-help reconstruction projects to give them the opportunity to work. (7) All citizen in the province must receive and protect them with brethren love. (8) The evacuated burned-forests must be reforestrated with the principle of "best trees to the best lands". (9) The seedlings of species that the forest owners select must anyhow be secured and supplied (10) The organization and function of the village forestry association must be strengthened to take effective care of the reforestated burned-forests.

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A Case Study of ART Counseling on Maladjusted Children's Self-Respect and Social Ability Development (부적응 아동의 자아존중감 및 사회성 발달을 위한 미술상담 사례연구)

  • Hong, Mi-Young;Cho, Bung-Hwan
    • The Korean Journal of Elementary Counseling
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    • v.8 no.1
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    • pp.109-122
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    • 2009
  • The purpose of this study was to put an art counseling program in the elementary school maladjusted child and helped the school life adjustment of the maladjusted child's self-respect and social ability development. For this purpose, picked out 4 people children who are the lowest score in the child where the total score is below 100 points sorted 6 grades of Y elementary school in Daejeon. The art counseling program as a reconstruction of the prior study to meet an object of this study was provided to children in experimental group at the researcher's classroom after school for 12 session, two sessions per week. For analyze the study result. First, for quantitatively analysis of an maladjusted behavior compared pre and post test of conduct of school life adjustments test. Second, for confirm the change of self-respect and social ability development pre and post test and analyzed comparison. Third, recognizing trial state change of an maladjusted children put a KSD pre and post test and analyzed comparison with contents of a picture. Fourth, every session of the qualitative analysis which describes the conduct quality of each child led and the maladjusted child should have been visible what kind of change after the art counseling program execution criminal record, compared. The result of the study is the art counseling program decreased the maladjust conduct of the maladjusted child and is effective to self-respect and social ability development of the maladjusted child. And the art counseling program letting induces the change which is affirmative psychologically with the maladjusted child. As a result, the art counseling program to help the self-respect of the maladjusted child and social ability development, and it will be more effective in the school life adjustment for the maladjusted child.

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

  • Jang, Hyon-Chol;Kim, Kyeong-Keun;Cho, Jae-Hwan;Seo, Jeong-Min;Lee, Haeng-Ki
    • Journal of the Korean Society of Radiology
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    • v.6 no.5
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    • pp.357-363
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    • 2012
  • The purpose of this study on head computed tomography scan corporate reorganization adaptive iteration algorithm using the statistical noise, and quality assessment, reduction of dose was evaluated. Head CT examinations do not apply ASIR group [A group], ASIR 50 applies a group [B group] were divided into examinations. B group of each 46.9 %, 48.2 %, 43.2 %, and 47.9 % the measured in the phantom research result of measurement of CT noise average were reduced more than A group in the central part (A) and peripheral unit (B, C, D). CT number was measured with the quantitive analytical method in the display-image quality evaluation and about noise was analyze. There was A group and difference which the image noise notes statistically between B. And A group was high so that the image noise could note than B group (31.87 HUs, 31.78 HUs, 26.6 HUs, 30.42 HU P<0.05). The score of the observer 1 of A group evaluated 73.17 on 74.2 at the result 80 half tone dot of evaluating by the qualitative evaluation method of the image by the bean curd clinical image evaluation table. And the score of the observer 1 of B group evaluated 71.77 on 72.47. There was no difference (P>0.05) noted statistically. And the inappropriate image was shown to the diagnosis. As to the exposure dose, by examination by applying ASIR 50 % there was no decline in quality of the image, 47.6 % could reduce the radiation dose. In conclusion, if ASIR is applied to the clinical part, it is considered with the dose written much more that examination is possible. And when examination, it is considered that it becomes the positive factor when the examiner determines.

Three Dimensional MRI and Software for Studying Normal Anatomical Structures of an Entire Body (온몸의 정상 해부구조물을 익히기 위한 3차원 자기공명영상 및 소프트웨어)

  • Lee, Yong-Sook;Park, Jin-Seo;Hwang, Sung-Bae;Cho, Jae-Hyun;Chung, Min-Suk
    • Investigative Magnetic Resonance Imaging
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    • v.9 no.2
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    • pp.117-133
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    • 2005
  • For identifying the pathological findings in magnetic resonance images (MRIs), normal anatomical structures in MRIs should be identified in advance. For studying the anatomical structures in MRIs, a learning tool that includes the followings is necessary. First, MRIs of the entire body; second, horizontal, coronal, and sagittal MRIs; third, segmented images corresponding to the MRIs; fourth, three dimensional (3D) images of the anatomical structures in the MRIs; fifth, software incorporating the MRIs, segmented images, and 3D images. Such a learning tool, however, is hard to obtain. Therefore, in this research, such a learning tool which helps medical students and doctors study the normal anatomical structures in MRIs was made as follows. A healthy young Korean male adult with standard body shape was selected. Six hundred thirteen MRIs of the entire body were scanned (slice thickness 3 mm, interslice gap 0 mm, field of view 480 mm${\times}$480 mm, resolution 512${\times}$512, T1 weighted), and transferred to the personal computer. Sixty anatomical structures in the MRIs were segmented to make segmented images. Coronal, sagittal MRIs and coronal, sagittal segmented images were made. On the basis of the segmented images, forty-seven anatomical structures 3D images were made by manual surface reconstruction method. Software incorporating the MRIs, segmented images, and 3D images was composed. This learning tool that includes horizontal, coronal, sagittal MRIs of the entire body, corresponding segmented images, 3D images of the anatomical structures in the MRIs, and software is expected to help medical students and doctors study the normal anatomical structures in MRIs. This learning tool will be presented worldwide through Internet or CD titles.

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Accuracy Evaluation of CT-Based Attenuation Correction in SPECT with Different Energy of Radioisotopes (SPECT/CT에서 CT를 기반으로 한 Attenuation Correction의 정확도 평가)

  • Kim, Seung Jeong;Kim, Jae Il;Kim, Jung Soo;Kim, Tae Yeop;Kim, Soo Mee;Woo, Jae Ryong;Lee, Jae Sung;Kim, Yoo Kyeong
    • The Korean Journal of Nuclear Medicine Technology
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    • v.17 no.1
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    • pp.25-29
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    • 2013
  • Purpose: In this study, we evaluated the accuracy of CT-based attenuation correction (AC) under the conventional CT protocol (140 kVp, on average 50-60 keV) by comparing the SPECT image qualities of different energy of radioisotopes, $^{201}Tl,\;^{99m}Tc$ and $^{131}I$. Materials and Methods: Using a cylindrical phantom, three different SPECT scans of $^{201}Tl$ (70 keV, 55.5 MBq), $^{99m}Tc$ (140 keV, 281.2 MBq) and $^{131}I$ (364 keV, 96.2 MBq) were performed. The CT image was obtained with 140 kVp and 2.5 mA in GE Hawkeye 4. The OSEM reconstruction algorithm was performed with 2 iterations and 10 subsets. The experiments were performed in the 4 different conditions; non-AC and non-scatter correction (SC), only AC, only SC, AC and SC in terms of uniformity and center to peripheral ratio (CPR). Results: The uniformity was calculated from the uniform whole region in the reconstructed images. For $^{201}Tl$ and $^{99m}Tc$, the uniformities were improved by about 10-20% AC was applied, but these were decreased by about 2% as SC was applied. The uniformity of $^{131}I$ was slightly increased as both AC and SC were applied. The CPR of the reconstructed image was close to one, when AC was applied for $^{201}Tl$ and $^{99m}Tc$ scans and $^{131}I$ was distant from 1 and that is only AC. Conclusion: The image uniformity improved by AC on low energy likely to $^{201}Tl$ and $^{99m}Tc$. However, image uniformity of high energy such as $^{131}I$ was improved, when both AC and SC was applied.

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Evaluating the Impact of Attenuation Correction Difference According to the Lipiodol in PET/CT after TACE (간동맥 화학 색전술에 사용하는 Lipiodol에 의한 감쇠 오차가 PET/CT검사에서 영상에 미치는 영향 평가)

  • Cha, Eun Sun;Hong, Gun chul;Park, Hoon;Choi, Choon Ki;Seok, Jae Dong
    • The Korean Journal of Nuclear Medicine Technology
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    • v.17 no.1
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    • pp.67-70
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    • 2013
  • Purpose: Surge in patients with hepatocellular carcinoma, hepatic artery chemical embolization is one of the effective interventional procedures. The PET/CT examination plays an important role in determining the presence of residual cancer cells and metastasis, and prognosis after embolization. The other hand, the hepatic artery chemical embolization of embolic material used lipiodol produced artifacts in the PET/CT examination, and these artifacts results in quantitative evaluation influence. This study, the radioactivity density and the percentage error was evaluated by the extent of the impact of lipiodol in the image of PET/CT. Materials and Methods: 1994 NEMA Phantom was acquired for 2 minutes and 30 seconds per bed after the Teflon, water and lipiodol filled, and these three inserts into the enough to mix the rest behind radioactive injection with $20{\pm}10MBq$. Phantom reconfigure with the iterative reconstruction method the number of iterations for two times by law, a subset of 20 errors. We set up region of interest at each area of the Teflon, water, lipiodol, insert artifact occurs between regions, and background and it was calculated and compared by the radioactivity density(kBq/ml) and the% Difference. Results: Radioactivity density of the each region of interest area with the teflon, water, lipiodol, insert artifact occurs between regions, background activity was $0.09{\pm}0.04$, $0.40{\pm}0.17$, $1.55{\pm}0.75$, $2.5{\pm}1.09$, $2.65{\pm}1.16 kBq/ml$ (P <0.05) and it was statistically significant results. Percentage error of lipiodol in each area was 118%, compared to the water compared with the background activity 52%, compared with a teflon was 180% of the difference. Conclusion: We found that the error due to under the influence of the attenuation correction when PET/CT scans after lipiodol injection performed, and the radioactivity density is higher than compared to other implants, lower than background. Applying the nonattenuation correction images, and after hepatic artery chemical embolization who underwent PET/CT imaging so that the test should be take the consideration to the extent of the impact of lipiodol be.

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The Evaluation of Image Correction Methods for SPECT/CT in Various Radioisotopes with Different Energy Levels (SPECT/CT에서 서로 다른 에너지의 방사성동위원소 사용시 영상보정기법의 유용성 평가)

  • Shin, Byung Ho;Kim, Seung Jeong;Yun, Seok Hwan;Kim, Tae Yeop;Lim, Jung Jin;Woo, Jae Ryong;Oh, So Won;Kim, Yu Kyeong
    • The Korean Journal of Nuclear Medicine Technology
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    • v.17 no.2
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    • pp.53-58
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    • 2013
  • Purpose: To optimize correction method for SPECT/CT, image quality consisting of resolution and contrast was evaluated using three radioisotopes ($^{99m}Tc$, $^{201}Tl$ and $^{131}I$) and three different correction methods; attenuation correction (AC), scatter correction (SC) and both attenuation and scatter correction (ACSC). Materials and Methods: Images were acquired with a SPECT/CT scanner and a conventional CT protocol with an OESM reconstruction algorithm (2 iterations and 10 subsets). For resolution measurement, fixed radioactivity (2.22 kBq) was infused into a spatial resolution phantom and full width at half maximum (FWHM) was measured using a vendor-provided software. For contrast evaluation, radioactive source with a ratio of 1:8 to background was filled in a Flanged Jaszczak phantom and percent contrast (%) were calculated. All the parameters for image quality were compared with non-correction (NC) method. Results: As compared with NC, image resolution of all three isotopes were significantly improved by AC and ACSC, not by SC. In particular, ACSC showed better resolution than AC alone for $^{99m}Tc$ and $^{201}Tl$. Image contrast of all three radioisotopes in a sphere with the largest diameter were enhanced by all correction methods. ACSC showed the highest contrast in all three radioisotopes, which was the most accurate in $^{99m}Tc$ (85.9%). Conclusion: Image quality of SPECT/CT was improved in all the radioisotopes by CT-based attenuation correction methods, except SC alone. SC failed to improve resolution in any radioisotopes, but it was effective in contrast enhancement. ACSC would be the best correction method as it improved resolution in radioisotopes with low energy levels and contrast in radioisotope with low energy levels. However, in radioisotope with high energy level, AC would be better than ACSC for resolution improvement.

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Quantitative Comparisons in $^{18}F$-FDG PET Images: PET/MR VS PET/CT ($^{18}F$-FDG PET 영상의 정량적 비교: PET/MR VS PET/CT)

  • Lee, Moo Seok;Im, Young Hyun;Kim, Jae Hwan;Choe, Gyu O
    • The Korean Journal of Nuclear Medicine Technology
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    • v.16 no.2
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    • pp.68-80
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    • 2012
  • Purpose : More recently, combined PET/MR scanners have been developed in which the MR data can be used for both anatometabolic image formation and attenuation correction of the PET data. For quantitative PET information, correction of tissue photon attenuation is mandatory. The attenuation map is obtained from the CT scan in the PET/CT. In the case of PET/MR, the attenuation map can be calculated from the MR image. The purpose of this study was to assess the quantitative differences between MR-based and CT-based attenuation corrected PET images. Materials and Methods : Using the uniform cylinder phantom of distilled water which has 199.8 MBq of $^{18}F$-FDG put into the phantom, we studied the effect of MR-based and CT-based attenuation corrected PET images, of the PET-CT using time of flight (TOF) and non-TOF iterative reconstruction. The images were acquired from 60 minutes at 15-minute intervals. Region of interests were drawn over 70% from the center of the image, and the Scanners' analysis software tools calculated both maximum and mean SUV. These data were analyzed by one way-anova test and Bland-Altman analysis. MR images are segmented into three classes(not including bone), and each class is assigned to each region based on the expected average attenuation of each region. For clinical diagnostic purpose, PET/MR and PET/CT images were acquired in 23 patients (Ingenuity TF PET/MR, Gemini TF64). PET/CT scans were performed approximately 33.8 minutes after the beginnig of the PET/MR scans. Region of interests were drawn over 9 regions of interest(lung, liver, spleen, bone), and the Scanners' analysis software tools calculated both maximum and mean SUV. The SUVs from 9 regions of interest in MR-based PET images and in CT-based PET images were compared. These data were analyzed by paired t test and Bland-Altman analysis. Results : In phantom study, MR-based attenuation corrected PET images generally showed slightly lower -0.36~-0.15 SUVs than CT-based attenuation corrected PET images (p<0.05). In clinical study, MR-based attenuation corrected PET images generally showed slightly lower SUVs than CT-based attenuation corrected PET images (excepting left middle lung and transverse Lumbar) (p<0.05). And percent differences were -8.01.79% lower for the PET/MR images than for the PET/CT images. (excepting lung) Based on the Bland-Altman method, the agreement between the two methods was considered good. Conclusion : PET/MR confirms generally lower SUVs than PET/CT. But, there were no difference in the clinical interpretations made by the quantitative comparisons with both type of attenuation map.

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