2D-PC MRA를 이용한 넥타이의 순간적인 壓迫이 내경정맥의 혈류에 미치는 영향에 대한 硏究

김긍식(Keung-Sik Kim),정태섭(Tae-Sub Chung),박인국(In-Kook Park),이범수(Bum-Soo Lee),김현수(Hyun-Soo Kim),유병규(Beong-Gyu Yoo) 대한방사선과학회(구 대한방사선기술학회) 2008 방사선기술과학 Vol.31 No.3

  본 연구는 20세에서 50세까지 건강한 남성 지원자를 대상으로 내경동맥과 내경정맥의 혈류속도를 측정하기 위하여 2D-PC MRA를 촬영했다.<BR>  2D-PC MRA는 제4-5경추디스크를 지나는 FOV 24㎝ 넓이로 횡단 촬영하여 내경동맥과 내경정맥의 혈류속도를 넥타이를 매지 않은 상태와 세게 맨 상태에서 각각 측정하였다.<BR>  넥타이를 매지 않았을 때 내경동맥의 평균 혈류속도 최고치는 우측 72.13 ㎝/sec, 좌측 74.96 ㎝/sec (양측평균 73.54 ㎝/sec)이였고 내경정맥의 평균 혈류속도 최고치는 우측 -34.45 ㎝/sec, 좌측 -24.99 ㎝/sec(양측평균 -29.72 ㎝/sec)였다. 그러나 넥타이를 세게 매었을 때 내경동맥의 평균 혈류속도 최고치는 우측 61.35 ㎝/sec, 좌측 65.19 ㎝/sec(양측 평균 63.27 ㎝/sec)이며 내경정맥의 혈류속도 최고치는 우측 -22.14 ㎝/sec, 좌측 -17.93 ㎝/sec (양측 평균 20.03 ㎝/sec)였다.<BR>  목에 세게 넥타이를 맨 경우가 넥타이를 매지 않은 상태 보다 양쪽 내경동맥의 평균 혈류속도가 86%(63.27/73.54 ㎝/sec)로 약간 감소하는 반면 양쪽 내경정맥의 평균 혈류속도는 67%(-20.03/-29.72 ㎝/sec)로 유의성 있게 감소하였다(P < 0.05). 따라서 넥타이를 세게 매었을 때 내경정맥의 순환에 미치는 영향(33%의 혈류속도감소)이 내경동맥(14%의 혈류속도감소) 보다 유의성 있게 큰 것을 알 수 있었다(P < 0.05).<BR>  결론적으로 본 연구결과는 2D-PC MRA를 이용하여 넥타이를 목에 세게 매었을 때 순간적으로 양쪽 내경정맥이 내경동맥보다 상대적으로 압박되어 혈류속도가 의미 있게 감소되며 일시적 폐쇄가 되는 소견을 보였다. 이 경우 넥타이를 목에 세게 매고 생활을 하는 경우에 대변을 보거나 또는 세면을 하는 등 일상적인 생활에서도 예기치 않게 일시적으로 내경정맥혈관이 압박되어 폐쇄되며 이차적으로 두개강 내의 정맥성고혈압을 일으켜 뇌졸중의 요인이 될 수 있는 것으로 유추된다.   The 25 healthy male volunteers aged from 20 to 50 years old have been employed in this study. 2D-PC MRA was performed to measure the velocity of the blood flow in the internal carotid artery and internal jugular veins using 3.0T MRI Whole body (signa VH/i GE). ECTRICKS-CEMRA was performed to evaluate the pattern of blood circulation from internal carotid artery to internal jugular vein. Using 2D-PC MRA, the cross-section of the 4th and 5th cervical discs was scanned with 24 ㎝  FOV. Then the speed of blood flow was measured for internal carotid artery and internal jugular vein when the subject wears a necktie tightly and no tie.<BR>  The average of maximum velocity of internal carotid arteries without a necktie was 72.13 ㎝/sec in the right side and 74.96 ㎝/sec in the left side(average 73.54 ㎝/sec in both sides) while the average of maximum velocity of internal jugular veins without a necktie was -34.45 ㎝/sec in the right side and -24.99 ㎝/sec in the left side (-29.72 ㎝/sec in both sides).<BR>  However, when wearing a necktie tightly, the average of maximum velocity of internal carotid arteries was 61.35 ㎝/sec in the right side and 65.19 ㎝/sec in the left side(average 63.27 ㎝/sec in both sides) while the average of maximum velocity of internal jugular veins was -22.14 ㎝/sec in the right side and -17.93 ㎝/sec in the left side(-20.03 ㎝/sec in both sides). With the necktie tightly knotted, the average blood flow speed of both internal carotid arteries slightly decreased to 86% (63.27/73.54 ㎝/sec) compared to no tie case in which both internal jugularveins significantly went down to 67% (-20.03/-29.72 ㎝/sec).<BR>  Thus it is suggested that wearing a necktie affects the circulation of internal jugular veins(33% decrease in blood flow speed) more significantly than that of internal carotid artery(14% decrease in blood flow speed). Without a necktie, ECTRICKS-CEMRA showed natural blood circulation patterns of internal carotid arteries and internal jugular veins without any disturbances or compressions. However, when wearing a necktie tightly, ECTRICKS-CEMRA showed severe compression onto both internal jugular veins in all 25 volunteers.<BR>  In conclusion, the result of the study showed that the tightly worn necktie instantly presses more internal jugular veins than internal carotid arteries, thereby significantly reducing the blood flow speed and leading to the temporary occlusion. Thus, the defecation or washing the face under the tightly tied necktie situations can cause the unexpected and temporary compression or occlusion of the internal jugular veins, subsequently leading to the occurrences of the stroke due to the secondary intracranial venous hypertension.

대퇴 근위부 골절환자에서 이중에너지 방사선흡수계측법을 이용한 부위별 골밀도 비교

이종석,김긍식,유병규 대한방사선과학회(구 대한방사선기술학회) 2000 방사선기술과학 Vol.23 No.2

유방 X-선 촬영술에서 한국 여성의 적정 압박력에 대한 고찰과 촬영 조건 비교

김영화,김긍식,권영갑,Kim Young Wha,Kim Keung Sik,Kwon Young Kap 대한방사선사협회 2002 대한방사선사협회지 Vol.28 No.1

Purpose : For the woman, compression of breast during mammogram introduce pain that woman used to have fear for mammogram. Therefore, the purpose of this study was to determine the adequate and minimized compression power for mammogram with maintaining th

Cf-252 중선자 선원을 이용한 수소화금속의 중성자 방사선 차폐능 평가

유병규,김긍식,김용수 대한방사선사협회 2003 대한방사선사협회지 Vol.29 No.1

Cf-252 중성자 선원을 이용한 수소화금속의 중성자 방사선 차폐능 평가

유병규,김긍식,김용수 대한방사선과학회(구 대한방사선기술학회) 2003 방사선기술과학 Vol.26 No.3

자체 개발한 수소화금속을 이용하여 고속 중성자 방사선을 효율적으로 차폐할 수 있다면 방사선 안전신기술 개발과 확립에 큰 기여를 할 것으로 생각되어 본 연구를 시행하였다. 여러 수소화 안정 금속들을 대상으로 핵적 특성, 단위 부피당 수소원자함유 수 등의 예비평가를 통하여 수소화금속(ZrH₂, TiH₂) 등과 낮은 중성자 흡수 단면적과 높은 에너지 감쇄능력을 고려하여 중수소화금속(ZrD₂, TiD₂) 등을 추가하여 개발하였다. MCNP 코드를 이용하여 각각의 흡수율과 에너지 감소율을 평가하였다. 전산 모사 계산과 실험과의 비교평가를 위해 실험과 동일한 조건의 모사를 수행하였는데, 즉 중성자 선원은 Cf-252( 10mCi)을 사용하였으며 각 수소화금속의 0, 1, 3, 5 ㎝ 두께를 통과한 중성자속의 강도와 에너지별 분포변화를 계산하였다. 코드 계산을 통해 평가된 TiH₂/TiD₂,ZrH₂/ZrD₂ 등의 수소화금속에 대한 중성자 감소율은 각 수소화 금속 두께의 증가에 따라 중성자 감소율이 지수적으로 증가함을 보였다. 또한 이 때 중수소 함유 금속, ZrD₂과 TiD₂는 중성자 흡수에 있어 ZrH₂와 TiH₂의 각각 보다 적게 나타났다. 본 연구를 통하여 개발된 수소화금속의 중성자 방사선 차폐에 관한 결과는 과학 기술적으로 많은 이용과 아울러 학술적 연구뿐만 아니라 실제 실용화를 위한 연구의 기초자료로 충분한 활용이 있을 것으로 기대한다. Mitigation of fast neutron irradiation damage on reactor vessel and improvement of mechanical integrity are desired for the successful plant life-time extension. In this study, the performance of metallic hydride for this application is reviewed and compared. First, selected prospective metallic hydrides are evaluated by MCNP code and put into the attenuation test using Cf-252 neutron source. Since for the reactor application high moderation and reflection with no absorption are favored, Z factor is introduced for the evaluation. According to the Z value estimation ZrD₂ and TiD₂ are turned out to be the most favorable fast neutron shielding materials. More thorough evaluation by computer simulation and experimentally, will be followed.

흉부CT 검사 시 HRCT 영상 재구성의 유용성

박성민,김긍식,강성민,유병규,이기배,Park, Sung-Min,Kim, Keung-Sik,Kang, Seong-Min,Yoo, Beong-Gyu,Lee, Ki-Bae 대한디지털의료영상학회 2015 대한디지털의료영상학회논문지 Vol.17 No.1

Purpose : Skip the repetitive HRCT axial scan in order to reduce the exposure of patients during chest HRCT scan, Helical Scan Data into a reconstructed image, and exposure of the patient change and visually evaluate the usefulness of the HRCT images. Materials and method : Patients were enrolled in the survey are 50 people who underwent chest CT scans of patients who presented to the hospital from January 2015 to March 2015. 50 people surveyed 22 people men and 28 people women people showed an average distribution of 30 to 80 years age was 48 years. 50 patients to Somatom Sensation 64 ch (Siemens) model with 120 kVp tube voltage to a reference mAs tube current to mAs (Care dose, Siemens) as a whole, including the lungs and the chest CT scan was performed. Scan upon each patient CARE dose 4D (Automatic exposure control, Siemens Medical Solution Erlangen, Germany) was to maintain the proper radiation dose scan every cross-section through a device that automatically adjusts the tube current of. CT scan is the rotation time of the Tube slice collimation, slice width 0.6 mm, pitch factor was made under the terms of 1.4. CT scan obtained after the raw data (raw data) to the upper surface of the axial images and coronal images for each slice thickness 1 mm, 5 mm intervals in the high spatial frequency calculation method (hight spatial resolution algorithm, B60 sharp) was the use of the lung window center -500 HU, windows were reconstructed into images in the interval -1000 HU to see. Result : 1. Measure the total value of DLP 50 patients who proceed to chest CT group A (Helical Scan after scan performed with HRCT) and group B (Helical Scan after the HR image reconstruction to the original data) compared with the group divided, analysis As a result of the age, but show little difference for each age group it had a decreased average dose of about 9%. 2. A Radiation read the results of the two Radiologist and a doctor upper lobe and middle lobe of the lung takes effect the visual evaluation is not a big difference between the two images both, depending on the age of the patient, especially if the blood vessels of the lower lobe (A: 3.4, B: 4.6) and bronchi(A: 3.8, B4.7) image shake caused by breathing in anxiety (blurring lead) to the original data (raw data) showed that the reconstructed image is been more useful in diagnostic terms. Conclusion : Scan was confirmed a continuous, rapid motion video to get Helical scan is much lower lobe lung reduction in visual blurring, Helical scan data to not repeat the examination by obtaining HRCT images reorganization reduced the exposure of the patient.

Multidetector-Row Computed Tomography(MDCT) Corronary Agniography에서 Arrhythmia Correction이 영상의 질에 미치는 영향에 관한 연구

김현수(Hyun Soo Kim),김긍식(Keung Sik Kim),김태훈(Tae Hoon Kim),유병규(Beong Gyu Yoo) 대한방사선과학회(구 대한방사선기술학회) 2004 방사선기술과학 Vol.27 No.2

MDCT는 비침습적인 방볍으로 관상동맥 질환을 검사하는데 유용하다고 알려져 있다. 하지만 영상의 질에 있어서 환자의 심장박동이 결정적인 영향을 주게 된다. 특히 심장박통이 불규칙하거나 조기 심설수축 환자일 경우 영상을 재구성하는데 있어 왜곡 현상이 증가하여 진단에 어려움을 초래한다. 최근 본원에서 심장박동이 불규칙한 환자에서 영상 재구성시 불규칙한 R-R 간격을 조정한 후 얻은 영상이 artifact가 감소하는 현상을 경험한 바 있다. 따라서 본 연구에서는 다양한 교정 방법(disable, inesrt, R-R interval 교정)이 영상의 질에 어떤 영향이 있는지를 알아보고자 한다. 심박동이 불규칙한 24명의 환자에서 교정방법에 따라 영상을 재구성한 결과 R-R Interval 조정에서 통계학적으로 유의한 결과를 얻을 수 있었다(p<0.05). 본 연구에서는 R-R Interval 조정에서 가장 우수한 영상을 얻을 수 있었으며, 향후 심장 질환의 진단에 도움을 줄 수 있는 기초연구로서 그 가치가 충분하리라 사료된다. MDCT is a useful, non-invasive, diagnostic tool in the evaluation of coronary artery disease. However, the image quality is affected by an irregular heart rhythm of the patients. Especially, premature ventricular contraction induced stair-step artifacts in the reconstruction of 2-D or 3-D images of the heart including coronary arteries. In recent, we experienced some improving of the image quality after correcting the PVC. Accordingly, the purpose of our study was to evaluate the effectiveness of the arrhythmia correction method, which was commer챠ally available software, in improving the quality of the reconstruction images of the heart. Image analysis Was performed, in consensus, by two radiologists. The scores for image quality were ranked as follows; excellent is 4 (image quality is markedly improved and is helpful in the Image evaluation), good is 3 (image quality is mildly improved, but is somewhat helpful in the image evaluation), fair is 2 (image quality is improved and is not helpful in the image evaluation), and poor is 1 (image quality is not improved). We used ANOVA method to evaluate the statistical significant differences in the image qualities among the correction methods of the arrhythmia with below 0.05 of p-value. The method of moving the R-R interval showed statistically significant differences in improving of the image quality in patients with arrhythmia. We concluded that the regulation of R-R interval in patients with arrhythmia was an effective method to improve the image quality in the reconstructions of the MDCT coronary angiograms.

석회화된 관상동맥 질환에서 16 Slice MDCT의 Kernel 값이 관상동맥 내경협착에 미치는 영향평가에 대한 연구

김현수(Hyun Soo Kim),김긍식(Keung Sik Kim),이춘배(Choon Bae Lee) 대한전산화단층기술학회 2006 대한CT영상기술학회지 Vol.8 No.1

Purpose The purposes of this study were to evaluate the effect to change of kernel factors using 16 slice multi-dectector computed tomography. Materials and Methods Twenty patients were evaluated for subsistence calcification of coronary artery. Twenty asymptomatic subject(8 womwn, 12 men; age range, 54~83; mean age 65 years) underwent 16 slice multi-detector computed tomography. MDCT was performed on a 16 slice multi-dectector computed tomography with a standard coronary protocol(detector collimation 12×0.75mm, table feed 6.8mm/rotation, rotation time 420 ms, tube current time 150mAs, tube voltage 120kVp). Agaston scores and maximun intensity projection were performed with a workstation. MIP image evaluation was performed by two radiologists in a consensus decision on a eight-point scale: 1=severe blooming artifact, 8=small blooming artifact. For evaluation of images window width 900 and windoq center 400 were used. Results The point of reading that the B40f kernel were very higher than other kernel the score 7.5. And blooming artifact is the lowest at the kernel of B50f. Conclusion We recommended high resolution kernel(B40f) for evaluation of coronary artery lumen with cacification.

폐소공포증 환자의 핵의학 영상검사에 관한 연구

강용길,홍진웅,양한준,박성수,이귀원,김긍식,Kang, Yong-Gil,Hong, Jin-Woong,Yang, Han-Joon,Park, Sung-Su,Lee, Gui-Won,Kim, Keung-Sik 대한디지털의료영상학회 2013 대한디지털의료영상학회논문지 Vol.15 No.1

Patients who had claustrophobia tend to feel fear when they were scanned by an MRI, CT, PET-CT, or using a gamma camera scan. In this paper, claustrophobic patients were tested to find effective ways by changing patient's positions. For this paper, PET-CT scan in patients who had claustrophobia were used in the prone position. Prone position helped to maintain stable position and to get a h0igh quality of inspection without failure. Thus, as claustrophobic patients were requested taking prone position, they could feel comfortable. In a confined space, prone position for the claustrophobic patients who had a fear of the PET-CT examination would be expected to reduce the failure rate of inspection.