Analysis of the Brain-activation Areas During the Visual Stimulations of 2D and 3D Imagery using Functional Magnetic Resonance Imaging

Yeong-Cheol Heo,Hae-Kag Lee,Jae-Hwan Cho 한국자기학회 2017 Journal of Magnetics Vol.22 No.4

The aim of this study is an functional magnetic resonance imaging (fMRI) investigation of the activity of the Brodmann brain areas during the viewing of 2D and 3D images. By using the 3.0 Tesla MRI system, an 8-channel SENSE Head Coil, and the ESys fMRI system in 5 adult males, 3D T1-weighted images were obtained from anatomic images. A gradient-EPI sequence was used for the acquisition of the brain functional images. The monitor was installed so that the images could be seen through a mirror located in the coil. The 3D appearance of the triangular, cubic, and hexagonal shapes were visually stimulated by the 2D and 3D images, and a pair of red–blue cardboard glasses was worn during the viewing of the 3D images. The display object is composed of 4 stimulus projections every 60 s and 4 resting periods of 20 s every 20 s. The acquired data were analyzed using the SPM-8 program. For the 2D imagery, the activation area of the brain is larger than that of the 3D imagery (p < .05). In the visual-cortex activation area, the number of clusters is larger for the 3D imagery (p < .05). It is expected that the basic data of this study will be used to analyze the effects of 3D-image contents on the areas of the human brain.

Effects of NEX on SNR and Artifacts in Parallel MR Images Acquired using Reference Scan

Yeong-Cheol Heo,Hae-Kag Lee,Jae-Hwan Cho 한국자기학회 2013 Journal of Magnetics Vol.18 No.4

The aim of this study was to investigate effects of the number of acquisitions (NEX) on signal-to-noise (SNR) and artifacts in SENSE parallel imaging of magnetic resonance imaging (MRI). 3.0T MR System, 8 Channel sensitivity encoding (SENSE) head coils were used along with an in-vivo phantom. Reference sequence of 3D fast field echo (FFE) was consisted of NEX values of 2, 4, 6, 8, 10 and 12. The T2 turbo spin echo (TSE) sequence used for exams achieved SENSE factors of 1.2, 1.5, 1.8, 2.0, 2.2, 2.5, 2.8, 3.0, 3.2, 3.5, 3.8 and 4.0. Exams were conducted five times for each SENSE factor to measure signal intensity of the object, the posterior phase-encode direction and frequency direction. And SNR was calculated using mean values. SENSE artifacts were identified as background signal intensity in the phase-encoded direction using MRIcro. It was found that SNR increased but SENSE artifacts reduced with NEX of 4, 8 and 12 when the NEX increased in reference scan. It is therefore concluded that image quality can be improved with NEX of 4, 8 and 12 for reference scanning.

Accuracy Analysis of Magnetic Resonance Angiography and Computed Tomography Angiography Using a Flow Experimental Model

Yeong-Cheol Heo,Hae-Kag Lee,Cheol-Soo Park,Jae-Hwan Cho 한국자기학회 2015 Journal of Magnetics Vol.20 No.1

This study investigated the accuracy of magnetic resonance angiography (MRA) and computed tomography angiography (CTA) in terms of reflecting the actual vascular length. Three-dimensional time of flight (3D TOF) MRA, 3D contrast-enhanced (CE) MRA, volume-rendering after CTA and maximum intensity projection were investigated using a flow model phantom with a diameter of 2.11 mm and area of 0.26 ㎠. 1.5 and 3.0 Tesla devices were used for 3D TOF MRA and 3D CE MRA. CTA was investigated using 16 and 64 channel CT scanners, and the images were transmitted and reconstructed by volume-rendering and maximum intensity projection, followed by conduit length measurement as described above. The smallest 3D TOF MRA measure was 2.51 ± 0.12 ㎜ with a flow velocity of 40 cm/s using the 3.0 Tesla apparatus, and 2.57 ± 0.07 ㎜ with a velocity of 71.5 ㎝/s using the 1.5 Tesla apparatus; both images were magnified from the actual measurement of 2.11 ㎜. The measurement with the 16 channel CT scanner was smaller (3.83 ± 0.37 ㎜) than the reconstructed image on maximum intensity projection. The images from CTA from examination apparatus and reconstruction technique were all larger than the actual measurement.

Study of Apparent Diffusion Coefficient Changes According to Spinal Disease in MR Diffusion-weighted Image

Yeong-Cheol Heo,Jae-Hwan Cho 한국자기학회 2017 Journal of Magnetics Vol.22 No.1

In this study, we compared the standardized value of each signal intensity, the apparent diffusion coefficient (ADC) that digitizes the diffusion of water molecules, and the signal to noise ratio (SNR) using b value 0 400, 1400 (s/mm²). From March 2013 to December 2013, patients with suspicion of simple compound fracture and metastatic spine cancer were included in the MR readout. We used a 1.5 Tesla Achieva MRI system and a Syn- Spine Coil. Sequence is a DWI SE-EPI sagittal (diffusion weighted imaging spin echo-echo planar imaging sagittal) image with b-factor (s/mm²) 0, 400, 1400 were used. Data analysis showed ROI (Region of Interest) in diseased area with high SI (signal intensity) in diffusion-weighted image b value 0 (s/mm²) Using the MRIcro program, each SI was calculated with images of b-value 0, 400, and 1400 (s/mm²), ADC map was obtained using Metlab Software with each image of b-value, The ADC is obtained by applying the ROI to the same position. The standardized values (SI400/SI0, SI400/SI0) of simple compression fractures were 0.47 ± 0.04 and 0.23 ± 0.03 and the standardized values (SI400/SI0, SI400/SI0) of the metastatic spine were 0.57 ± 0.07 and 0.32 ± 0.08 And the standardized values of the two diseases were statistically significant (p < 0.05). The ADC (mm²/s) for b value 400 (s/mm²) and 1400 (s/mm²) of the simple compression fracture disease site were 1.70 ± 0.16 and 0.93 ± 0.28 and 1.24 ± 0.21 and 0.80 ± 0.15 for the metastatic spine. The ADC (mm²/s) for b value 400 (s/mm²) was statistically significant (p < 0.05) but the ADC (mm²/s) for b value 1400 (p > 0.05). In conclusion, multi - b value recognition of signal changes in diffusion - weighted imaging is very important for the diagnosis of various spinal diseases.

한국인 원인 불명 조기폐경 환자의 FMR1 유전자 양상

허창영 ( Heo Chang Yeong ),최영민 ( Choe Yeong Min ),박성효 ( Park Seong Hyo ),윤병구 ( Yun Byeong Gu ),이규섭 ( Lee Gyu Seob ),나용진 ( Na Yong Jin ),이병석 ( Lee Byeong Seog ),류철희 ( Lyu Cheol Hui ),이화진 ( Lee Hwa Jin ),설 대한산부인과학회 2003 Obstetrics & Gynecology Science Vol.46 No.5

Objective : To explore the incidence of fragile X premutation in patients with idiopathic premature ovarian failure, particularly in the Korean population. Design : A prospective study. Materials and Methods : Eighty-three women affected by idiopathic premature ovarian failure were recruited for this study. Patient with known causes of premature ovarian failure were excluded : cytogenetic abnormalities, prior chemotherapy, prior bilateral oophorectomy. DNA was extracted from peripheral blood. Fragile X (FRAXA) premutation was evaluated by PCR amplification of and Southern blot analysis for FMR1 gene. Results : The FRAXA premutation was detected in three (3.6%) out of 83 patients with idiopathic premature ovarian failure. Conclusion : This result suggests that fragile X premutation screening is indicated in patients with idiopathic premature ovarian failure, particularly in the Korean population.

국내외 학술지 발표논문 : 한국인 원인 불명 조기폐경 환자의 FMR1 유전자 양상

허창영 ( Heo Chang Yeong ),최영민 ( Choe Yeong Min ),박성효 ( Park Seong Hyo ),윤병구 ( Yun Byeong Gu ),이규섭 ( Lee Gyu Seob ),나용진 ( Na Yong Jin ),이병석 ( Lee Byeong Seog ),류철희 ( Lyu Cheol Hui ),이화진 ( Lee Hwa Jin ),설 서울대학교 인구의학연구소 2003 人口醫學硏究論集 Vol.16 No.-

당뇨병성 혈액투석 환자에서 동정맥루 조기 기능부전과 심혈관 사망률과의 연관성

김영옥 ( Kim Yeong Og ),윤선애 ( Yun Seon Ae ),송호철 ( Song Ho Cheol ),허기훈 ( Heo Gi Hun ),양철우 ( Yang Cheol U ),진동찬 ( Jin Dong Chan ),김용수 ( Kim Yong Su ),김석영 ( Kim Seog Yeong ),최의진 ( Choe Ui Jin ),장윤식 ( Jang Y 대한신장학회 2003 Kidney Research and Clinical Practice Vol.22 No.4

배 경 : 당뇨병성 만성 신부전증 환자에서 동정맥루 기능부전이 흔하게 발생하는 기전은 잘 알려져 있지 않지만 동정맥루 수술부위의 혈관 상태 불량과 관련이 있을 것으로 추정되고 있다. 그러므로 당뇨병성 만성 신부전증 환자에서 동정맥루 기능부전이 심혈관 사망률과 관련이 있을 것으로 추측되고 있으나 현재까지 이에 대한 보고가 없다. 이에 저자들은 당뇨병성 신부전증 환자에서 동정맥루 조기 기능부전과 심혈관계 사망에 어떠한 영향을 끼치는지를 조사하였다. 방 법 : 1995년 1월부터 2000년 12월까지 가톨릭대학교 의정부성모병원에서 동정맥루 수술을 시행 받은 당뇨병성 신부전증 환자 144명을 대상으로 하였다. 수술 후 1년 이내에 발생한 동정맥루 기능부전을 조사하고 2002년 12월까지 심혈관 사망률을 조사하였다. 전체 환자를 동정맥루 조기 기능부전군과 개존군으로 나누어 두 군간에 심혈관계 사망률을 Kaplan-Meier 방법과 log rank test를 이용하여 분석하였으며 심혈관계 이외의 사망과 추적 관찰 소실은 censored data로 처리하였다. 대상 환자의 평균 연령은 58±11세이었고 남자는 57명 (39.6%)이었다. 결 과 : 전체 144명 환자 증 동정맥루 조기 기능부전은 68명에서 발생하였다 (47.2%). 32±20개월의 추적 관찰 기간 동안 심혈관 사망은 62명 (43.1%)에서 발생하였다. 동정맥루 조기 기능부전군 (n=68)의 추적 관찰기간은 개존군 (n=76)에 비해 통계적 차이는 없었으나 짧은 경향을 보였다 (29±17 vs 35±22개월, p=0.07). 그러나 이 기간 동안 조기 기능부전군은 개존군에 비해 급성 심근경색증 (13.2% vs 3.9%, p=0.044), 울혈성 심부전증 (70.5% vs 13.1%, p<0.001), 말초동백질환 (20.5% vs 3.9%, p=0.002)의 발생빈도가 각각 높았다. 조기 기능부전군의 심혈관 사망률은 정상군에 비해 유의하게 높았다 (3년; 54.6% vs 24.6%, 5년; 77.0% vs 42.3%, p=0.005). 결 론 : 혈액투석을 받고 있는 당뇨병성 신부전증 환자에서 동정맥루 조기 기능부전은 심혈관 사망률과 관련이 있을 것으로 추정된다. Background : Although the exact mechanism in which vascular acces failure frequently occurs in hemodialysis patients with diabetes mellitus is not well known, it is considered to be associated with the poor quality of the vessel at the vascular access operation sites. Therefore, vascular access failure may be associated with cardiovascular mortality in the diabetic patients, but it is not reported yet. We studied the impact of early vascular access failure on the cardiovascular morbidity in the hemodialysis patients with diabetes mellitus. Methods : This retrospective study enrolled 144 patients who received vascular access operation between January, 1995 and December, 2000 at Uijongbu St. Mary`s Hospital. We investigate vascular access failure within 1 year after the access operation and evaluated the cardiovascular death until December, 2002. We analyzed the cardiovascular mortality between early vascular failure group and patent group using Kaplan-Meier method and log rank test. Results : The mean age of the parients was 58±11 years and the number of male was 57 (39.6%). Early vascular access failure developed in 68 patients (47.2%). During 32±20 months of mean follow-up period, there was 62 cardiovascular deaths. The follow-up period tended to be shorter in the access failure group (n=68) than the patent group (n=76) (29±17 months vs 35±22 months, p=0.07). But the access failure group had higher incidence of acute myocardial infarction (13.2% vs 3.9%, p=0.044), congestive heart failure (70.5% vs 13.1%, p<0.001), and peripheral arterial disease (20.5% vs 3.9%, p=0.002), compared to the patent group. The cardiovascular mortality of the access failure group was higher than that of the patent group (3 year; 54.6% vs 24.6%, 5 year; 77.0% vs 42.3%, p=0.005). Conclusion : This data suggest that early vascular access failure is associated with the cardiovascular morbidity and mortality in hemodialysis patients with diabetes mellitus. (Korean J Nephrol 2003;22(4):397-404)

Test of Homogeneity Baseon Complex Survey Data : Discussion Based on Power of Test

Heo, Sun-Yeong,Yi, Su-Cheol The Korean Data and Information Science Society 2005 한국데이터정보과학회지 Vol.16 No.3

In the secondary data analysis for categorical data, situations often arise in which the estimated cell variances are available, but not the full matrix of variances. In this case researchers are often inclined to use Pearson-type test statistics for homogeneity. However, for a complex sample observed cell proportions are not distributed as multinomial and Pearson-type test statistic generally is not distributed asymptotically as chi-square distribution. This paper evaluates powers for Wald test and Pearson-type test and the first order corrected test of Pearson-type test for homogeneity. The resulting power curves indicate that as the misspecification effect increases, the amount of inflation of significance level and the loss of power Pearson-type test are getting more severe.

Randomized dose-finding clinical trial of oncolytic immunotherapeutic vaccinia JX-594 in liver cancer

Heo, Jeong,Reid, Tony,Ruo, Leyo,Breitbach, Caroline J,Rose, Steven,Bloomston, Mark,Cho, Mong,Lim, Ho Yeong,Chung, Hyun Cheol,Kim, Chang Won,Burke, James,Lencioni, Riccardo,Hickman, Theresa,Moon, Anne Nature Publishing Group, a division of Macmillan P 2013 Nature medicine Vol.19 No.3

Oncolytic viruses and active immunotherapeutics have complementary mechanisms of action (MOA) that are both self amplifying in tumors, yet the impact of dose on subject outcome is unclear. JX-594 (Pexa-Vec) is an oncolytic and immunotherapeutic vaccinia virus. To determine the optimal JX-594 dose in subjects with advanced hepatocellular carcinoma (HCC), we conducted a randomized phase 2 dose-finding trial (n = 30). Radiologists infused low- or high-dose JX-594 into liver tumors (days 1, 15 and 29); infusions resulted in acute detectable intravascular JX-594 genomes. Objective intrahepatic Modified Response Evaluation Criteria in Solid Tumors (mRECIST) (15%) and Choi (62%) response rates and intrahepatic disease control (50%) were equivalent in injected and distant noninjected tumors at both doses. JX-594 replication and granulocyte-macrophage colony-stimulating factor (GM-CSF) expression preceded the induction of anticancer immunity. In contrast to tumor response rate and immune endpoints, subject survival duration was significantly related to dose (median survival of 14.1 months compared to 6.7 months on the high and low dose, respectively; hazard ratio 0.39; P = 0.020). JX-594 demonstrated oncolytic and immunotherapy MOA, tumor responses and dose-related survival in individuals with HCC.

온열요법이 인체 신세포암세포주에서 P당단백 발현과 Glutathione 함량 및 Glutathione관련 효소의 활성도에 미치는 영향

허영철,이은식,박원희 大韓泌尿器科學會 1999 Korean Journal of Urology Vol.40 No.2