Correction with blood T1 is essential when measuring post-contrast myocardial T1 value in patients with acute myocardial infarction

Choi, Eui-Young,Hwang, Sung Ho,Yoon, Young Won,Park, Chul Hwan,Paek, Mun Young,Greiser, Andreas,Chung, Hyemoon,Yoon, Ji-Hyun,Kim, Jong-Youn,Min, Pil-Ki,Lee, Byoung Kwon,Hong, Bum-Kee,Rim, Se-Joong,Kwo BioMed Central 2013 Journal of cardiovascular magnetic resonance Vol.15 No.-

<P><B>Background</B></P><P>Post-contrast T1 mapping by modified Look-Locker inversion recovery (MOLLI) sequence has been introduced as a promising means to assess an expansion of the extra-cellular space. However, T1 value in the myocardium can be affected by scanning time after bolus contrast injection. In this study, we investigated the changes of the T1 values according to multiple slicing over scanning time at 15 minutes after contrast injection and usefulness of blood T1 correction.</P><P><B>Methods</B></P><P>Eighteen reperfused acute myocardial infarction (AMI) patients, 13 cardiomyopathy patients and 8 healthy volunteers underwent cardiovascular magnetic resonance with 15 minute-post contrast MOLLI to generate T1 maps. In 10 cardiomyopathy cases, pre- and post-contrast MOLLI techniques were performed to generate extracellular volume fraction (Ve). Six slices of T1 maps according to the left ventricular (LV) short axis, from apex to base, were consecutively obtained. Each T1 value was measured in the whole myocardium, infarcted myocardium, non-infarcted myocardium and LV blood cavity.</P><P><B>Results</B></P><P>The mean T1 value of infarcted myocardium was significantly lower than that of non-infarcted myocardium (425.4±68.1 ms vs. 540.5±88.0 ms, respectively, p< 0.001). T1 values of non-infarcted myocardium increased significantly from apex to base (from 523.1±99.5 ms to 561.1±81.1 ms, p=0.001), and were accompanied by a similar increase in blood T1 value in LV cavity (from 442.1±120.7 ms to 456.8±97.5 ms, p<0.001) over time. This phenomenon was applied to both left anterior descending (LAD) territory (from 545.1±74.5 ms to 575.7±84.0 ms, p<0.001) and non-LAD territory AMI cases (from 501.2±124.5 ms to 549.5±81.3 ms, p<0.001). It was similarly applied to cardiomyopathy patients and healthy volunteers. After the myocardial T1 values, however, were adjusted by the blood T1 values, they were consistent throughout the slices from apex to base (from 1.17±0.18 to 1.25±0.13, p>0.05). The Ve did not show significant differences from apical to basal slices.</P><P><B>Conclusion</B></P><P>Post-contrast myocardial T1 corrected by blood T1 or Ve, provide more stable measurement of degree of fibrosis in non-infarcted myocardium in short- axis multiple slicing.</P>

인라인 스케이트 이용자들의 손상 유형과 위험 요인

서혜경,문지영,성주욱,김말영,이준호,박정이,차성화,백나영,이재민,김수민,임현술,정해관,배근량,정철 東國大學校醫學硏究所 2004 東國醫學 Vol.11 No.2

지난 몇 년 사이 인라인 스케이트는 젊은층을 중심으로 인기있는 스포츠가 되었으며 이러한 대중화와 더불어 인라인 스케이트와 관련된 사고 빈도도 증가하는 추세이다. 따라서 본 연구는 인라인 스케이트 이용에 따른 사고율과 이용습관 형태, 손상 유형 및 위험 요인을 알아보고자 시행되었다. 2003년 9월 14일부터 9월 24일까지 경주시 ○○초등학교 6학년, ○○중학교 1학년, ○○여자고등학교 1학년, ○○고등학교 1학년, 동국대학교 의과대학 의학과 학생, 경주황성·포항 해맞이 공원의 성인을 포함한 총설문 대상자 1,305명 중 인라인 스케이트 이용자 392명을 대상으로 단면 연구를 수행하였다. 조사에 앞서 병원 방문과 사전 조사를 시행 하였으며 자기 기입식 설문지를 통해 정보를 수집하였다. 초, 중, 고 인라인 스케이트 전체 이용률은 28.1% 사고율은 30.1%로 나왔으며 주로 젊은층에서 사고가 많았으며 나이가 증가할수록 빈도가 증가하였다. 보호 장비 착용률은 44.4%로 조사되었다. 손상 부위로는 무릎과 상지 부위가 많은 것으로 조사되었으며 손상 유형은 찰과상과 타박상이 많았다. 스케이트를 타기 시작한지 1개월 이내에서 사고를 가장 많이 당한 것으로 나타났다. 전체 부상자의 20%가 후유증이 있었던 것으로 나타났다. 본 연구에서 인라인 스케이트 이용자들의 사고율이 비교적 높음을 알 수 있었다. 손상 부위의 무릎 및 상지 집중 현상으로 인해 무릎과 상지 부위의 보호대 착용이 필요할 것으로 생각되며 또한 사고를 줄이기 위해 초기 기술 습득 단계부터 전문가를 통한 체계적 교육과 안전 의식 고양이 필요할 것으로 보인다. In the past several years, Inline skating has become a popular sport among young people. With popularization of Inline skating, the number of injuries has increased proportionately. The purpose of this study is to evaluate the prevalence of injuries, the behaviors of skating, the nature and risk factors of injuries. We conducted a questionnaire an 1,305 subjects from Sep. 14 to 24, 2003. The Inline skaters were 392. These participation were mainly students from ○○elementary school, ○○middle school, ○○women's high school, ○○high school, Dongguk medical school, and adult skaters in several parks. The prevalence of injuries were 30.1%. Injuries were predominant from younger age and frequencies were increased according to increasing age. The most common location of injuries were both knee and the upper extremities. Most of injury type were skin abrasion and contusion. Injuries were highest within one month after First skating. 20% of injuries experienced a sequela. The results of this study show the severity of Inline skating-related injuries. We expect that the knee and the upper extrimities protectors should be used adequatly. Also to reduce injuries, when the skills are obtainded, the specilized learning programs and safety awareness are needed.

Terahertz Time Domain Spectroscopy, T-Ray Imaging and Wireless Data Transfer Technologies

Mun Cheol Paek,Min Hwan Kwak,Seung Beom Kang,Sungil Kim,Han-Cheol Ryu,Sang Kuk Choi,Se Young Jeong,Dae Won Kang,Dong Suk Jun,Kwang Yong Kang 한국전자파학회JEES 2010 Journal of Electromagnetic Engineering and Science Vol.10 No.3

This study reviewed terahertz technologies of time domain spectroscopy, T-ray imaging, and high rate wireless data transfer. The main topics of the terahertz research area were investigation of materials and package modules for terahertz wave generation and detection, and setup of the terahertz system for time domain spectroscopy(TDS), T-ray imaging and sub-㎔ wireless communication. In addition to Poly-GaAs film as a photoconductive switching antenna material, a table-top scale for the ㎔-TDS/imaging system and terahertz continuous wave(CW) generation systems for sub-㎔ data transfer and narrow band T-ray imaging were designed. Dielectric properties of ferroelectric BSTO(BaxSr1-x TiO₃) films and chalcogenide glass systems were characterized with the ㎔-TDS system at the ㎔ frequency range. Package modules for terahertz wave transmitter/receiver(Tx/Rx) photoconductive antenna were developed.

테라헤르츠파 발진/검출용 광전도안테나 패키지 모듈

백문철(Mun Cheol Paek),최상국(Sang KuK Choi),곽민환(Min Hwan Kwak),강승범(Seung Beom Kang),정세영(Se Young Jeong),강광용(Kwang Yong Kang) 대한전자공학회 2010 대한전자공학회 학술대회 Vol.2010 No.6

2단계 Epitaxy 성장법을 이용한 Autodoping 의 제어

신영호(Young Ho Shin),정호선(Ho Seon Chung),백문철(Mun Cheol Paek),송성해(Sung Hae Song) 대한전자공학회 1983 대한전자공학회 학술대회 Vol.1983 No.11

Zinc finger protein 143 expression is closely related to tumor malignancy via regulating cell motility in breast cancer

( A Rome Paek ),( Ji Young Mun ),( Kyeong-man Hong ),( Jongkeun Lee ),( Dong Wan Hong ),( Hye Jin You ) 생화학분자생물학회(구 한국생화학분자생물학회) 2017 BMB Reports Vol.50 No.12

We previously reported the involvement of zinc-finger protein 143 (ZNF143) on cancer cell motility in colon cancer cells. Here, ZNF143 was further characterized in breast cancer. Immunohistochemistry was used to determine the expression of ZNF143 in normal tissues and in tissues from metastatic breast cancer at various stages. Notably, ZNF143 was selectively expressed in duct and gland epithelium of normal breast tissues, which decreased when the tissue became malignant. To determine the molecular mechanism how ZNF143 affects breast cancer progression, it was knocked down by infecting benign breast cancer cells with short-hairpin (sh) RNA-lentiviral particles against ZNF143 (MCF7 sh-ZNF143). MCF7 sh-ZNF143 cells showed different cell-cell contacts and actin filament (F-actin) structures when compared with MCF7 sh-Control cells. In migration and invasion assays, ZNF143 knockdown induced increased cellular motility in breast carcinoma cells. This was reduced by the recovery of ZNF143 expression. Taken together, these results suggest that ZNF143 expression contributes to breast cancer progression. [BMB Reports 2017; 50(12): 621-627]

Diagnosis of Acute Global Myocarditis Using Cardiac MRI with Quantitative T1 and T2 Mapping: Case Report and Literature Review

박철환,최의영,Andreas Greiser,Mun Young Paek,황성호,김태훈 대한영상의학회 2013 Korean Journal of Radiology Vol.14 No.5

The diagnosis of myocarditis can be challenging given that symptoms, clinical exam findings, electrocardiogram results, biomarkers, and echocardiogram results are often non-specific. Endocardial biopsy is an established method for diagnosing myocarditis, but carries the risk of complications and false negative results. Cardiac magnetic resonance imaging (MRI) has become the primary non-invasive imaging tool in patients with suspected myocarditis. Myocarditis can be diagnosed by using three tissue markers including edema, hyperemia/capillary leak, and necrosis/fibrosis. The interpretation of cardiac MR findings can be confusing, especially when the myocardium is diffusely involved. Using T1 and T2 maps, the diagnosis of myocarditis can be made even in cases of global myocarditis with the help of quantitative analysis. We herein describe a case of acute global myocarditis which was diagnosed by using quantitative T1 and T2 mapping.

Differentiation between Focal Malignant Marrow-Replacing Lesions and Benign Red Marrow Deposition of the Spine with T2*-Corrected Fat-Signal Fraction Map Using a Three-Echo Volume Interpolated Breath-Hold Gradient Echo Dixon Sequence

김용표,Stephan Kannengiesser,Mun Young Paek,김성준,정태섭,유연화,윤춘식,송호택,이영한,서진석 대한영상의학회 2014 Korean Journal of Radiology Vol.15 No.6

Objective: To assess the feasibility of T2*-corrected fat-signal fraction (FF) map by using the three-echo volume interpolated breath-hold gradient echo (VIBE) Dixon sequence to differentiate between malignant marrow-replacing lesions and benign red marrow deposition of vertebrae. Materials and Methods: We assessed 32 lesions from 32 patients who underwent magnetic resonance imaging after being referred for assessment of a known or possible vertebral marrow abnormality. The lesions were divided into 21 malignant marrow-replacing lesions and 11 benign red marrow depositions. Three sequences for the parameter measurements were obtained by using a 1.5-T MR imaging scanner as follows: three-echo VIBE Dixon sequence for FF; conventional T1-weighted imaging for the lesion-disc ratio (LDR); pre- and post-gadolinium enhanced fat-suppressed T1-weighted images for the contrast-enhancement ratio (CER). A region of interest was drawn for each lesion for parameter measurements. The areas under the curve (AUC) of the parameters and their sensitivities and specificities at the most ideal cutoff values from receiver operating characteristic curve analysis were obtained. AUC, sensitivity, and specificity were respectively compared between FF and CER. Results: The AUCs of FF, LDR, and CER were 0.96, 0.80, and 0.72, respectively. In the comparison of diagnostic performance between the FF and CER, the FF showed a significantly larger AUC as compared to the CER (p = 0.030), although the difference of sensitivity (p = 0.157) and specificity (p = 0.157) were not significant. Conclusion: Fat-signal fraction measurement using T2*-corrected three-echo VIBE Dixon sequence is feasible and has a more accurate diagnostic performance, than the CER, in distinguishing benign red marrow deposition from malignant bone marrow-replacing lesions.

Comparison of Multi-Echo Dixon Methods with Volume Interpolated Breath-Hold Gradient Echo Magnetic Resonance Imaging in Fat-Signal Fraction Quantification of Paravertebral Muscle

유연화,김학선,이영한,윤춘식,Mun Young Paek,유한나,Stephan Kannengiesser,정태섭,송호택,서진석,김성준 대한영상의학회 2015 Korean Journal of Radiology Vol.16 No.5

To assess whether multi-echo Dixon magnetic resonance (MR) imaging with simultaneous T2* estimation and correction yields more accurate fat-signal fraction (FF) measurement of the lumbar paravertebral muscles, in comparison with non-T2*-corrected two-echo Dixon or T2*-corrected three-echo Dixon, using the FF measurements from single-voxel MR spectroscopy as the reference standard. Sixty patients with low back pain underwent MR imaging with a 1.5T scanner. FF mapping images automatically obtained using T2*-corrected Dixon technique with two (non-T2*-corrected), three, and six echoes, were compared with images from single-voxel MR spectroscopy at the paravertebral muscles on levels L4 through L5. FFs were measured directly by two radiologists, who independently drew the region of interest on the mapping images from the three sequences. A total of 117 spectroscopic measurements were performed either bilaterally (57 of 60 subjects) or unilaterally (3 of 60 subjects). The mean spectroscopic FF was 14.3 ± 11.7% (range, 1.9–63.7%). Interobserver agreement was excellent between the two radiologists. Lin’s concordance correlation between the spectroscopic findings and all the imaging-based FFs were statistically significant (p < 0.001). FFs obtained from the T2*-corrected six-echo Dixon sequences showed a significantly better concordance with the spectroscopic data, with its concordance correlation coefficient being 0.99 and 0.98 (p < 0.001), as compared with two- or three-echo methods. T2*-corrected six-echo Dixon sequence would be a better option than two- or three-echo methods for noninvasive quantification of lumbar muscle fat quantification.

Comparison of Multi-Echo Dixon Methods with Volume Interpolated Breath-Hold Gradient Echo Magnetic Resonance Imaging in Fat-Signal Fraction Quantification of Paravertebral Muscle

Yoo, Yeon Hwa,Kim, Hak-Sun,Lee, Young Han,Yoon, Choon-Sik,Paek, Mun Young,Yoo, Hanna,Kannengiesser, Stephan,Chung, Tae-Sub,Song, Ho-Taek,Suh, Jin-Suck,Kim, Sungjun The Korean Society of Radiology 2015 KOREAN JOURNAL OF RADIOLOGY Vol.16 No.5

<P><B>Objective</B></P><P>To assess whether multi-echo Dixon magnetic resonance (MR) imaging with simultaneous T2* estimation and correction yields more accurate fat-signal fraction (FF) measurement of the lumbar paravertebral muscles, in comparison with non-T2*-corrected two-echo Dixon or T2*-corrected three-echo Dixon, using the FF measurements from single-voxel MR spectroscopy as the reference standard.</P><P><B>Materials and Methods</B></P><P>Sixty patients with low back pain underwent MR imaging with a 1.5T scanner. FF mapping images automatically obtained using T2*-corrected Dixon technique with two (non-T2*-corrected), three, and six echoes, were compared with images from single-voxel MR spectroscopy at the paravertebral muscles on levels L4 through L5. FFs were measured directly by two radiologists, who independently drew the region of interest on the mapping images from the three sequences.</P><P><B>Results</B></P><P>A total of 117 spectroscopic measurements were performed either bilaterally (57 of 60 subjects) or unilaterally (3 of 60 subjects). The mean spectroscopic FF was 14.3 ± 11.7% (range, 1.9-63.7%). Interobserver agreement was excellent between the two radiologists. Lin's concordance correlation between the spectroscopic findings and all the imaging-based FFs were statistically significant (<I>p</I> < 0.001). FFs obtained from the T2*-corrected six-echo Dixon sequences showed a significantly better concordance with the spectroscopic data, with its concordance correlation coefficient being 0.99 and 0.98 (<I>p</I> < 0.001), as compared with two- or three-echo methods.</P><P><B>Conclusion</B></P><P>T2*-corrected six-echo Dixon sequence would be a better option than two- or three-echo methods for noninvasive quantification of lumbar muscle fat quantification.</P>