• 보건행정학회지
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• 제31권3호
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• pp.261-271
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• 2021

Background: In 2018, the government increased the fee for the magnetic resonance imaging (MRI) image deciphering services of the external hospital to discourage the redundant MRI scan and to induce appropriate use of the MRI services. It is important to evaluate the effect of the policy to provide the basis for establishing other MRI-related policies. Methods: The healthcare data of the patients who had brain MRI scans were organized by episode and analyzed using the panel study in order to find out the effect of the MRI-related policy on the substitution effect and the medical expenses. Results: As a result of the increase in the fee of deciphering the MRI image, there has been an uplift in deciphering the MRI scan of the external hospital. It implies that more hospitals chose to use the MRI scan taken by other clinics or hospitals, rather than the MRI scan taken at their own facilities. Conclusion: The research results imply that a policy that facilitates the exchange of the medical image data between the hospitals is needed in order to establish an efficient management system of the healthcare resources. Such improvement is expected to reduce the social cost and contribute to the stability in the finance of national health insurance.

• 한국방사선학회논문지
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• 제5권4호
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• pp.201-205
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• 2011

아급성기 발목염좌 환자의 진단에 임상에서 주로 이용되는 방법으로 내.외반 스트레스 검사(ankle stress-varus, valgus) 및 전방 당김 검사(anterior-draw)와 MRI 검사에 의한 연부 조직과 근육, 인대의 질환이 진단가치가 높다라는 관점에서 주로 이용하고 있다. 진단적 가치에 대한 부분의 차이점은 적으나 MRI 검사의 경우 시간적 경제적 부담이 큰 만큼 두 가지의 대표적 검사를 비교 하여 (특정 병원의 환자 그룹을 대상으로 연구를 진행) 단순방사선 검사에 의한 족근골 질환의 진단이 MRI 검사에 비하여 유용성과 효율성이 낮지 않다는 결과를 도출 할 수 있었다.

• Investigative Magnetic Resonance Imaging
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• 제21권2호
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• pp.91-96
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• 2017

Purpose: To describe technical methods for functional magnetic resonance imaging (fMRI) study with arterial spin labeling (ASL) compared to blood oxygenation level-dependent (BOLD) technique and discuss the potential of ASL for research and clinical practice. Materials and Methods: Task-based (n = 1) and resting-state fMRI (rs-fMRI) (n = 20) were performed using ASL and BOLD techniques. Results of both techniques were compared. Results: For task-based fMRI with finger-tapping, the primary motor cortex of the contralateral frontal lobe and the ipsilateral cerebellum were activated by both BOLD and ASL fMRI. For rs-fMRI of sensorimotor network, functional connectivity showed similar results between BOLD and ASL. Conclusion: ASL technique has potential application in clinical and research fields because all brain perfusion imaging, CBF measurement, and rs-fMRI study can be performed in a single acquisition.

• 한국정보통신학회논문지
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• 제14권4호
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• pp.948-958
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• 2010

MRI 시스템이 수집하는 인체신호는 매우 미약하기 때문에 영상화 과정을 거치면서 외부 잡음이나 시스템 불안정성에 의한 영향을 쉽게 받을 수 있다. 따라서 본 논문에서는 저 자장 MRI시스템에서 RF 수신코일의 디자인적 요소에 의해 발생되는 불균일성을 분석하여 영상의 균일도 향상 기법을 제안한다. 본 논문에서는 MRI영상의 신호강도 불균일성을 보정하기 위한 방법 중에서 팬텀 데이터를 이용하여 확장된 크기를 갖는 3차원 bias 볼륨 데이터를 획득하기 위한 방법을 제안함으로써 다양한 크기를 갖는 영상의 보정이 가능하도록 하였다. 제안된 bias 데이터의 최적화 기법을 적용하여 실험을 수행한 결과 단일 bias 데이터의 사용으로 다양한 영상법에 의한 영상을 효과적으로 보정할 수 있음을 확인 하였다.

• Tuberculosis and Respiratory Diseases
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• 제56권6호
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• pp.571-584
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• 2004

Magnetic Resonance Imaging (MRI) is one of the most advanced imaging techniques in clinical and research medicine. However, clinical application of MRI to the lung or thorax has been limited due to various drawbacks. Low signal intensity of the lung and cardiac and respiratory movements are the most serious problems with MRI in thorax. Nevertheless, MRI is superior to CT in some selected patients with thoracic diseases. The role of clinical MRI in thoracic disease has been widened with improvement of MR equipments and development of new pulse sequences. Otherwise, functional assessment of lung by MRI has been studied for the last decade. These include perfusion MRI with or without contrast enhancement and ventilation MRI with oxygen-enhancement or hyperpolarized noble gas, $^3He$ and $^{129}Xe$.

• 경영과학
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• 제21권2호
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• pp.93-109
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• 2004

The imports of used medical equipment such as CT. MRI have been rapidly increased every year. How to manage those medical equipment has been one of critical issues in the government sector. In this study, we demonstrate how benefit/cost analysis using the Analytic Hierarchy Process (AHP) can be applied to the comparison of used CT/MRI and new CT/MRI. The final results show that the new CT/MRI is more attractive than the used CT/MRI.

• 한국의학물리학회지:의학물리
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• 제31권3호
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• pp.35-53
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• 2020

The authors congratulate the cerebrations for the 30 years of the Korean Society of Medical Physics (http://www.ksmp.or.kr/). The paper is published to recognize the anniversary. Geon-Ho Jahng invited Professor Z. H. Cho to join to submit this manuscript because he has been one of the leaders in the field of magnetic resonance imaging (MRI) during the last 40 years. In this review, we describe the development and clinical histories of MRI internationally and domestically. We also discuss diffusion and perfusion MRI, molecular imaging using MRI and MR spectroscopy (MRS), and the hybrid systems, such as positron emission tomography-MRI (PET-MRI), MR-guided focused ultrasound surgery (MRgFUS), and MRI-guided linear accelerators (MRI-LINACs). In each part, we discuss the historical evolution of the developments, technical developments, and clinical applications.

• 보건행정학회지
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• 제8권1호
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• pp.155-182
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• 1998

There exists a remarkable differences in use of MRI scanning among income classes. The poor can hardly utilize it. This is because, among high cost technnologies, MRI is the only equipment not covered under health insurance benefits in Korea. This study was designed 1) to reveal the status of nation-wide MRI installation, customary charges and per unit annual scanning performance, and 2) to analyse factors influencing the above variables. The data for this study came from "MRI Prevalence Survey" conducted by the National Federation of Medcial Insurance(NFMI) in 1997, and were analyzed through SAS packages for T-test, analysis of variance and stepwise multiple regression. Data were collected from 188 hospitals equipped with MRI scanners. Major findings are summarized as follows : The number of MRI scanners has increased from 69 in 994 to 158 in 1996(2.3 times) while per unit annual scanning performance has risen by 11.2% from 2,173 cases in 1994 to 2,417 cases in 1996. Such a rapid increase was made possible mainly due to the inclusion of CT scanning under the health insurance benefit package. The customary charges for MRI scanning with or without contrast media, on average, amounted to 484,000 Won and 402,000 Won, respectively, with the percentile increase of 17.8% and 8.1% each during the same time. Korea ranks the third worldwidely in terms of number of MRI installations, 4.8 scanners per one million persons, only next to Japan and United States. Geographical variation of MRI, however, was rather high, 7.91 unit, in Cheju area compared to 1.82 in Kyongnam area. Variations of customary charges of MRI scanning can be explained as much as by 44.8% by both the total amount of claims to NFMI and geographical variable. The charges were more likely to be higher in metropolitan areas like Seoul and in hospitals with a bigger amount of claims. While those of per unit annual scanning performance can be explained as much as by 30.7% by both MRI installation cost and level of MRI-installed organizations. Per capital scannig performance was higher in tertiary hospitals and hospitals equipped with more expensive scanners than hospitals with less expensive scanners. Two measures are called for the remedying the existing excessive abundance in MRI units in korea : One is to set a ceiling of MRI units in an area like a province or a metropolitan district. The other is to establish a committee on introduction of high cost technologies for reviewing its effective use.ctive use.

• 대한골관절종양학회지
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• 제20권2호
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• pp.60-65
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• 2014

목적: 연부조직 종양 중 지방종과 신경초종(Schwannoma)은 자기공명영상촬영(MRI)만으로 충분한 진단적 가치를 가지는 종양이다. 하지만 신경초종의 경우 종양의 특성상 MRI에서 다양한 형태의 영상으로 나타날 수 있고, 신경주변에 생긴 다른 종양이 MRI상 신경초종으로 오인되는 경우도 드물지 않게 있다. 따라서 MRI상 신경초종으로 의심되는 환자를 대상으로 하여 MRI에서 신경초종을 감별할 수 있는 인자들을 찾아보고자 하였다. 대상 및 방법: 2002년 1월부터 2013년 5월까지 술 전 자기공명영상촬영(MRI)상 신경초종(schwannoma)이 의심된 환자 104예를 대상으로 하였으며 모든 환자에서 수술적 치료를 통한 조직검사를 시행하여 최종 진단 하였다. 조직 검사 결과 신경초종이 나온 경우를 1군으로 하고, 다른 병변이 나온 경우를 2군으로 나누어서 MRI 상 신경초종을 의심할 수 있는 영상의학적 소견을 비교 분석하였다. 결과: 104예의 조직검사 결과 신경초종으로 진단된 경우는 92예이며, 신경초종 외에 다른 병변으로 진단된 경우는 12예였다. MRI 특이 소견중 target sign은 1군에서는 41예(45%), 2군에서는 없었으며, fascicular sign은 1군에서는 47예(51%), 2군에서는 2예(17%), fat split sign은 1군에서는 44예(48%), 2군에서는 5예(42%), nerve entering and exiting sign은 1군에서는 28예(30%), 2군에서는 1예(9%)가 나타났다. 위 네가지 소견 모두 나타나지 않은 경우는 1군에서 8예(9%), 2군에서 6예(50%) 였다. 종양이 신경 주행 경로에 있는 경우는 1군에서 52예(57%), 2군에서 5예(42%)였다. Chi-squared test를 이용한 통계학적 분석에서, 위의 네가지 소견 중 target sign이 신경초종의 진단과 유의한 관계를 보였다(p<0.05). 결론: 신경초종 진단에 MRI가 중추적인 역할을 하고 있지만, 신경초종이 지닌 여러가지 특성으로 인해 MRI상 신경초종으로 의심된 경우라고 하더라도 최종적으로는 다른 종양으로 확진 된 경우가 드물지 않게 있다. 그러므로 MRI상 과녁징후가 보이지 않는 신경초종의 경우에는 다른 종양의 가능성도 염두에 두고 접근을 해야 할 것으로 보인다.

• Journal of Radiation Protection and Research
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• 제31권2호
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• pp.91-96
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• 2006

The effects of Magnetic resonance imaging (MRI) on mouse embryos at the early stage of organogenesis were investigated. Pregnant ICR mice were exposed on day 8 of gestation to MRI at 0.5 T for 0.5 hour to 3 hours. The mortality rates of embryos or fetuses, the incidence of external malformations, fetal body weight and sex ratio were observed at day 18 of gestation. A significant increase in embryonic mortality was observed after exposure to either 0.5 T MRI for 0.5 hour or 2 hours. However, the exposure to MRI for 1 hour or 3 hours did not induce any significant increase in embryonic mortality when compared with control. External malformations such as exencephaly, cleft palate and anomalies of tail were observed in all experimental groups exposed to each MRI. A statistically significant increase of external malformations was observed in all groups treated with 0.5 T MRI for 0.5 hour and 3 hours. The incidence of external malformations in the mice group exposed to 0.5 T MRI for 0.5-hour was found to be higher than those of mice group exposed to 0.5 T MRI for 2 hours. The effects of MRI on the external malformations might not to be dose-dependent. There was no statistically significant difference in fetal body weight and sex ratio among each MRI exposure groups.