• 한국방사선학회논문지
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• 제18권2호
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• pp.135-144
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• 2024

초음파 영상 검사는 지방간 정량화에 제한점을 가지고 있다. 이에 본 연구에서는 가상 지방간 팬텀을 통해 지방간 함량을 초음파 주행 과정에서의 신호 감쇠 변화가 정량화가 가능한지를 실험적으로 입증하고자 하고자 하였다. 또한 초음파 영상에서의 지방 함량과 신호 강도의 관계를 분석하여 초음파를 통한 지방간 진단에 대한 가능성을 평가하고자 하였다. 본 연구에서는 물과 기름을 균질하게 혼합하여 총 5개의 가상 지방간 팬텀을 개발했다. 자기공명영상과 초음파 영상을 사용하여 팬텀의 지방 함량을 확인하고 초음파 영상에서 거리에 따른 신호 강도를 측정하였다. 이후 지방 함량과 신호 강도 간의 상관관계를 분석과 평균비교를 수행하였다. 초음파 영상에서는 지방의 함량이 높아짐에 따라 초음파의 투과 강도가 감소하는 현상을 확인하였으며, 이를 통해 초음파를 사용하여 지방간의 함량을 정량화할 가능성을 확인하였다. 또한 자기공명영상으로 측정한 지방 함량과 초음파 영상에서 측정한 신호 강도 간 높은 상관관계를 보였다. 본 연구에서는 지방의 함량이 높아질수록 초음파 영상의 초음파 주행 과정에서 신호를 표현한 기울기(US-GRE)값이 점점 작아지는 것을 통계적으로 확인하였으며 US-GRE는 지방간 함량을 표현하는 생체 마커(biomarker)로서 역할을 할 수 있을 것으로 판단된다.

• 대한방사선기술학회지:방사선기술과학
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• 제30권4호
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• pp.313-320
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• 2007

[ $\ulcorner$ ]의료기사 등에 관한 법률$\lrcorner$에는 다수 직종을 총괄하여 규정하고 있어 방사선사 업무의 전문성 향상과 방사선의료기술에 대한 국민의 건강권을 보장하기 어렵다. 따라서 방사선사에 관련된 법령을 개별적으로 제정하는것이 요청된다. 개별법으로서 방사선사법은 궁극적으로 국민의 건강증진을 목적으로 하는 방사선사의 책임규제에 관한 법으로 제정되어야 한다. 이를 위해 전문방사선사에 대한 규정을 신설하고 보수교육과 면허관리제도의 강화를 통하여 국민들이 보다 수준 높은 양질의 방사선의료기술을 제공받을 수 있도록 하여야 한다. 또한 방사선사의 역할과 업무를 명확히 규정하여 국민에게 제공되는 의료방사선서비스의 질적 수준을 확보하여야 한다. 정부기관에는 의료방사선정책심의위원회를 두어 의료방사선의 안전관리와 방사선사 인력의 수급, 기타 의료방사선정책에 관한 중요한 사항이 검토되고, 심의되어야 한다. 그밖에 방사선조사선량의 기록, 관리를 통하여 방사선피폭으로부터 국민의 건강보호를 위한 규정도 필요하며, 팀의료의 일원으로서 방사선사의 지위가 보장되어야 한다.

• Journal of Korean Neurosurgical Society
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• 제29권7호
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• pp.899-903
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• 2000

Objective : Object : A 7-year retrospective clinical and MRI study was reviewed to evaluate the characteristics of pineal cyst. We evaluated results of clinical and radiologic change of pineal cyst during follow up period. Patients and Methods : From 1992 to 1999, 50 patients with pineal cyst were visited for evaluation. Follow up clinical information was obtained from patients or clinical record through phone conversation. also radiologic findi-ngs of pineal cyst in mid-sagittal MRI were reviewed in detail. Results : Pineal cysts were usually asymptomatic and detected incidentally during evaluation of other diseases. Sagittal MRI is the most useful diagnostic test. The radiologic findings of pineal cyst were isointensity on T1WI comared to CSF and slightly high signal intensity on T2WI. Cyst wall was variably enhanced on Gad-enhanced T1WI. The average size of cyst was $13.9{\times}13.0mm$. The pineal cyst was classified into five groups according to previous report. Long term behavior of these lesions are not apparent, but in our study they showed no specific changes in clinical and radiological aspects during 25 months. Conclusion : Although long-term follow up results are needed, the pineal cyst are considered as normal variants. In our 25 months follow up results, there was no rapid change of cyst both clinically and radiologically. Therefore, frequent radiologic evaluation seems unnecessary except type III pineal cyst.

• Korean Journal of Radiology
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• 제22권3호
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• pp.415-424
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• 2021

Objective: To determine whether noncontrast computed tomography (NCCT) models based on multivariable, radiomics features, and machine learning (ML) algorithms could further improve the discrimination of early hematoma expansion (HE) in patients with spontaneous intracerebral hemorrhage (sICH). Materials and Methods: We retrospectively reviewed 261 patients with sICH who underwent initial NCCT within 6 hours of ictus and follow-up CT within 24 hours after initial NCCT, between April 2011 and March 2019. The clinical characteristics, imaging signs and radiomics features extracted from the initial NCCT images were used to construct models to discriminate early HE. A clinical-radiologic model was constructed using a multivariate logistic regression (LR) analysis. Radiomics models, a radiomics-radiologic model, and a combined model were constructed in the training cohort (n = 182) and independently verified in the validation cohort (n = 79). Receiver operating characteristic analysis and the area under the curve (AUC) were used to evaluate the discriminative power. Results: The AUC of the clinical-radiologic model for discriminating early HE was 0.766. The AUCs of the radiomics model for discriminating early HE built using the LR algorithm in the training and validation cohorts were 0.926 and 0.850, respectively. The AUCs of the radiomics-radiologic model in the training and validation cohorts were 0.946 and 0.867, respectively. The AUCs of the combined model in the training and validation cohorts were 0.960 and 0.867, respectively. Conclusion: NCCT models based on multivariable, radiomics features and ML algorithm could improve the discrimination of early HE. The combined model was the best recommended model to identify sICH patients at risk of early HE.

• Journal of Yeungnam Medical Science
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• 제5권1호
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• pp.33-42
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• 1988

최근 5년간의 소아의 복부종괴 23예를 발생빈도, 부위 및 방사선학적 소견을 중심으로 비교분석하여 다음과 같은 결론을 얻었다. 1. 전체 23예중 신경아세포종이 6예로 가장 많았고 그 다음이 Wilms 종양 5예, 담도낭종, 난소종양, 수신종 등의 순위였다. 2. 발생연령별로 분석해 본 결과 6세 이하가 78%(14예)를 차지했고 특히 후복강 종양은 6세 이하에 집중되어 있었다. 3. 부위별로는 후복강 종양이 60%(14예)로 가장 많았다. 4. 방사선학적 소견을 분석하여 본 결과 1) 단순 복부촬영상 신경아세포종의 50%에서 특징적인 석회와 음영을 볼 수 있었고 후복강 종양의 대부분에서 비특이적인 석회화 음영을 볼 수 있었다. 2) 초음파 소견상 저에코, 고에코 또는 혼합에코 등의 종괴 내부성상을 알 수 있었으나 종괴의 정확한 해부학적 위치를 파악할 수 없는 경우가 많았다. 3) 경정맥 신우 조영촬영상 신우신배의 비정상적인 소견과 신장의 전위 소견으로부터 신장내 종양과 신장의 다른 부위의 종양을 구분할 수 있었다. 4) 전산화 단층촬영상 종괴 내부의 성상뿐만 아니라 종괴의 해부학적인 위치, 주위 구조와의 관계, 임파절이나 다른 부위로의 전이유무를 알 수 있었다.

• 대한디지털의료영상학회논문지
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• 제10권1호
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• pp.45-50
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• 2008

Recently, MR Cholangiography used mainly bu controlling of patient's breathing. There is breathing hold techniques to get images within shopt time and gating technique adjusted to respiration cycle for high resolution image. In this study, the aim of this experiment is to know on clinical usefulness compared with PACE and RTG thchniques. This study's period is from 2006 in November to 2007 in January. A total of 21 patients investigated at MAGNETOM Sonata 1.5T (SIEMENS Erlangen) with use of 12ch body coil. MR acquisition protocol used 3D turbo spin echo coronal sequence. Scan parameters applied to potimal setting in use as gating techniques, respectively. Analysis of consuming timing evaluated with rapidness. As analysis of quantity, the common bile duct, gall bladder measured in signal intensities, then these data were calculated by signal to noise ratio and contrast to noise ratio. Qualitative analysis, experienced 2radiologists and 3 RTs were evaluated into 3groups about artifact, accuracy of lesions, sharpness of the common bile duct or gall bladder. As a result of analysis, when compared to PACE, consuming time of the RTG took less than PACE, On both CNRs and SNRs, PACE technique was slightly high values than RTG(p<0.05). Qualitative analysis' results, discrimination of lesions in the common bile duct, gall bladder get a significance level in both RTG and PACE techniques but presence's artifact of breathing and pulsation highly demonstrate in PACE techniques. In conclusion, both PACE and RTG methods at MRCP provided prominently clinical information for the common bile duct, gall bladder. If machines have not limitation with performance, induction of breathing holding also will help getting diagnistic quality.

• Journal of Yeungnam Medical Science
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• 제26권1호
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• pp.30-37
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• 2009

RO는 경계가 좋은 고형종괴로써, 석회화를 포함할 수 있다. 조영전 CT 영상에서 신실질과 유사한 밀도의 균일한 종괴로 보인다. 조영 후 영상에서는 불균일하게 조영증강되는데, 역동적 조영증강 검사의 동맥강조기에서 주변부는 강하게 조영증강되었다가 시간에 따라 점차 조영이 약해지고, 중앙부는 시간에 따라 점차 조영이 증강되어 시간에 따른 조영증강의 부분적 역전현상이 관찰되었다. 이러한 영상의학적 특징이 관찰되는 경우에는 RO의 가능성을 시사할 수 있으며 이를 통해 환자의 예후를 예측하고 수술 방법을 술전에 결정하는데 도움을 줄 수 있으리라 생각한다.

• Imaging Science in Dentistry
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• 제54권2호
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• pp.207-210
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• 2024

Ameloblastic fibrodentinoma (AFD) is a rare benign odontogenic tumor that resembles an ameloblastic fibroma with dysplastic dentin. This report presents a rare case of mandibular AFD with imaging features in a young patient. Panoramic radiography and computed tomography revealed a well-defined lesion with internal septa and calcified foci, causing inferior displacement of the adjacent molars as well as buccolingual cortical thinning and expansion of the posterior mandible. The lesion was surgically removed via mass excision, and the involved tooth was extracted under general anesthesia. During the 5-year follow-up period, no evidence of recurrence was observed. Radiologic features of AFD typically reveal a moderately to well-defined mixed lesion with varying degrees of radiopacity, reflecting the extent of dentin formation. Radiologists should consider AFD in the differential diagnosis when encountering a multilocular lesion with little dense radiopacity, particularly if it is associated with delayed eruption, impaction, or absence of involved teeth, on radiographic images of young patients.

• Korean Journal of Radiology
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• 제20권4호
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• pp.542-557
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• 2019

The occurrence of incidentally detected pancreatic cystic lesions (PCLs) is continuously increasing. Radiologic examinations including computed tomography and magnetic resonance imaging with magnetic resonance cholangiopancreatography have been widely used as the main diagnostic and surveillance methods for patients with incidental PCLs. Although most incidentally detected PCLs are considered benign, they have the potential to become malignant. Currently, we have several guidelines for the management of incidental PCLs. However, there is still debate over proper management, in terms of accurate diagnosis, optimal follow-up interval, and imaging tools. Because imaging studies play a crucial role in the management of incidental PCLs, the 2017 consensus recommendations of the Korean Society of Abdominal Radiology for the diagnosis and surveillance of incidental PCLs approved 11 out of 16 recommendations. Although several challenges remain in terms of optimization and standardization, these consensus recommendations might serve as useful tools to provide a more standardized approach and to optimize care of patients with incidental PCLs.

• Imaging Science in Dentistry
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• 제51권2호
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• pp.149-154
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• 2021

Purpose: This study aimed to investigate the computed tomography and magnetic resonance imaging features of giant cell tumors in the temporomandibular joint region to facilitate accurate diagnoses. Materials and Methods: From October 2007 to June 2020, 6 patients (2 men and 4 women) at Yonsei University Dental Hospital had histopathologically proven giant cell tumors in the temporomandibular joint. Their computed tomography and magnetic resonance imaging findings were reviewed retrospectively, and the cases were classified into 3 types based on the tumor center and growth pattern observed on the radiologic findings. Results: The age of the 6 patients ranged from 25 to 53 years. Trismus was found in 5 of the 6 cases. One case recurred. The mean size of the tumors, defined based on their greatest diameter, was 32 mm (range, 15-41 mm). The characteristic features of all cases were a heterogeneously-enhancing tumorous mass with a lobulated margin on computed tomographic images and internal multiplicity of signal intensity on T2-weighted magnetic resonance images. According to the site of origin, 3 tumors were bone-centered, 2 were soft tissue-centered, and 1 was peri-articular. Conclusion: Computed tomography and magnetic resonance imaging yielded a tripartite classification of giant cell tumors of the temporomandibular joint according to their location on imaging. This study could help clinicians in the differential diagnosis of giant cell tumors and assist in proper treatment planning for tumorous diseases of the temporomandibular joint.