• Proceedings of the KSMRM Conference
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• 1999.11a
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• pp.123-124
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• 1999

• Korean Journal of Radiology
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• v.21 no.7
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• pp.812-828
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• 2020

Objective: To provide an evidence-based guide for the MRI interpretation of complete tumor response after neoadjuvant chemoradiation therapy (CRT) for rectal cancer using visual assessment on T2-weighted imaging (T2) and diffusion-weighted imaging (DWI). Materials and Methods: PubMed MEDLINE, EMBASE, and Cochrane Library were searched on November 28, 2019 to identify articles on the following issues: 1) sensitivity and specificity of T2 or DWI for diagnosing pathologic complete response (pCR) and the criteria for MRI diagnosis; 2) MRI alone vs. MRI combined with other test(s) in sensitivity and specificity for pCR; and 3) tests to select patients for the watch-and-wait management. Eligible articles were selected according to meticulous criteria and were synthesized. Results: Of 1615 article candidates, 55 eligible articles (for all three issues combined) were identified. Combined T2 and DWI performed better than T2 alone, with a meta-analytic summary sensitivity of 0.62 (95% confidence interval [CI], 0.43-0.77; I² = 80.60) and summary specificity of 0.89 (95% CI, 0.80-0.94; I² = 92.61) for diagnosing pCR. The criteria for the complete response on T2 in most studies had the commonality of remarkable tumor decrease to the absence of mass-like or nodular intermediate signal, although somewhat varied, as follows: (near) normalization of the wall; regular, thin, hypointense scar in the luminal side with (near) normal-appearance or homogeneous intermediate signal in the underlying wall; and hypointense thickening of the wall. The criteria on DWI were the absence of a hyperintense signal at high b-value (≥ 800 sec/mm²) in most studies. The specific algorithm to combine T2 and DWI was obscure in half of the studies. MRI combined with endoscopy was the most utilized means to select patients for the watch-and-wait management despite a lack of strong evidence to guide and support a multi-test approach. Conclusion: This systematic review and meta-analysis provide an evidence-based practical guide for MRI assessment of complete tumor response after CRT for rectal cancer.

• Clinical and Experimental Pediatrics
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• v.51 no.8
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• pp.787-791
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• 2008

Enlargement of organs or other solid tissues usually presents as an abdominal mass. Often, abdominal masses in children are found by an unsuspected parent or by a physician during a routine examination. Most masses have no specific signs or symptoms. Abdominal masses in children require immediate attention. History and physical examination may provide clues to the diagnosis. Ultrasound examination is the most useful screening test in most cases and may identify the organ involved and clarify whether the mass is solid or cystic. CT may be necessary to make a more precise diagnosis, especially solid masses. MRI is occasionally is helpful for specific abnormalities.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4431-4433
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• 2012

Aim: The aim of the present study was to evaluate retrospectively histopathologically-diagnosed lesions that were detected in the kidney after radical nephrectomy for a preoperative diagnosis of kidney cancer. Methods: The medical records of 83 patients (51 male, 32 female) were included. Preoperative staging was accomplished by various methods including physical examination, blood hemography and biochemistry, abdominal ultrasonography (US), chest x-ray, abdominal computed tomography (CT) and abdominal magnetic resonance imaging (MRI). Results: Totals of 70 patients underwent radical nephrectomy and 13 nephron sparing surgery. Of the 83 patients, 70 had malignant lesions (renal cell carcinoma, squamous cell carcinoma or other malignancies) 13 had a variety of benign lesions, the most frequently detected being oncoytoma (6), angiomyolipoma (3), xanthogranulamatous pyelonephritis (2), cortical cyst (1) and chronic pyelonephritic change (1). Conclusion: It was concluded that in spite of great technological developments regarding radiological imaging modalities such as US, CT and MRI, benign lesions might still be detected pathologically in patients who undergo radical nephrectomy with the preoperative diagnosis of renal cancer. But, all renal masses should be regarded as malignant and should be managed surgically otherwise proven benign.

• Proceedings of the Korea Contents Association Conference
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• 2011.05a
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• pp.525-526
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• 2011

복부 MRI 영상에서 간의 인식은 간에 존재하는 질병을 파악하는 것뿐만 아니라 간에 대한 치료 방법이나 수술 방법을 결정하는 중요한 정보를 제공한다. 따라서 본 논문은 복부 MRI 영상에서 이러한 간 영역과 간의 혈관을 자동으로 검출하는 알고리즘을 제안한다. 제안 알고리즘은 1단계로 Region Growing의 개선된 방법으로 초기 설정된 간 영역의 외곽선 정보를 이용하여 씨앗점을 설정해 간 영역을 초기 분할한다. 2단계로 분할된 영역 경계선의 지역적 최소값을 이용하여 경계선의 보정 작업을 수행한다. 이후 3단계로 추출된 간 영역을 기반으로 영상 개선 후, 인페인팅(In-painting) 기법을 활용하여 간 영역 내부의 혈관 부분을 검출하게 된다. 제안 알고리즘의 평가는 전문의의 수작업 결과와 비교하였고, 결과 82.5%의 평균 정확도를 보여 제안 알고리즘의 효과적인 간혈관 검출을 확인하였다. 향후 본 연구의 확장으로 검출된 혈관 영역의 3D Volume Rendering 연구를 수행할 예정이다.

• Journal of the Korean Society of Radiology
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• v.11 no.7
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• pp.619-625
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• 2017

The sudy was intended to evaluate the optimal equipment selection by quantitatively assessing the SNR(signal to noise ratio) and CNR(contrast to noise ratio) on the abdominal organ. This study performed on 1.5 T and 3.0 T MRI units focusing on HASTE, HASTE(f/s) and FFE(in of phase), FFE(out of phase) without using the contrast medium(Gadolinium). The data analysis was performed by randomly selecting on 1.5 T and 3.0 T abdominal MRI images. As a results, SNR and CNR values of 3.0 T is higher than 1.5 T at liver, kidney and spleen(p<0.05). Stomach, abdominal fat and pancreas was obtained a higher value at 1.5 T(p<0.05). On conclusion, the organs of outer part in the body showed generally a high value at 3.0 T, and the organs of inner part in the body including the gas showed a high value at 3.0 T because of a large difference on magnetic susceptibility.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.11
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• pp.4805-4811
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• 2016

Background: Hepatocellular carcinomas (HCCs) less than 2 cm in diameter generally demonstrate a good outcome after curative therapy. However, the diagnosis of small HCC can be problematic and requires one or more dynamic imaging modalities. This study aimed to compare the sensitivity and agreement between CT and MRI for the diagnosis of small HCCs. Methods: CT and/or MRI scans of HCCs (1-2 cm) diagnosed by histopathology or typical vascular pattern according to the 2005 AASLD criteria were blindly reviewed by an abdominal radiologist. The reports were defined as conclusive/typical when arterial enhancement and washout during the portal/delayed phases were observed and as inconclusive when typical vascular patterns were not observed. The sensitivity and Cohen's kappa (k) for agreement were calculated. Results: In 27 patients, 27 HCC nodules (1-2 cm) were included. Diagnosis with a single-imaging modality (CT or MRI) was 81 % versus 48 % (p = 0.01). The CT sensitivity was significantly higher than MRI (78 % versus 52 %, p = 0.04). Among 27 nodules that underwent both CT and MRI, a discordance in typical enhancement patterns was found (k = 0.319, p = 0.05). In cases with inconclusive CT results, MRI gave only an additional 3.7 % sensitivity to reach a diagnosis. In contrast, further CT imaging following inconclusive MRI results gave an additional 29.6 % sensitivity.Conclusions: A single typical imaging modality is sufficient to diagnose small HCCs. Compared with MRI, multiphasic CT has a higher sensitivity. The limitations of MRI could be explained by the greater need for patient cooperation and the types of MRI contrast agent.

• Journal of the Korean Society of Radiology
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• v.12 no.7
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• pp.869-877
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• 2018

This study analyzed the current status of MRI (frequency, amount of treatment) based on the history of application of the MRI health insurance benefit standard and health insurance claim data. MRI examinations began as a health insurance benefit in 2005. In 2005, the indications were restricted for some diseases, but coverage for benefits in 2010, 2013, 2016, and 2018 was expanded. In 2021, the Ministry of Health and Welfare decided to apply health insurance for all MRI examinations. From 2010 to 2017, the number of MRI examinations increased by 86.7% in 2017 compared to 2010, and the amount of treatment increased by 53.5%. According to general characteristics, the number of MRI examinations was higher in women than in men. By age, the number of examinations was the highest among ages 70-79. Outpatient examinations were more frequent than inpatient examinations, and the number of examinations in the tertiary hospitals was the highest among the types of hospitals. The number of brain MRI examinations was the highest in each exam site. In December 2013, the standard of MRI was expanded for heart disease and Crohn's disease, the number of cardiac MRI and abdominal MRI examinations increased in 2014 compared to 2013. However, the number of examinations is small and not associate with the disease, it would be difficult to say that it affected the increase in the total number of MRI examinations. To assess health insurance sustainability and policy effectiveness, monitoring will be necessary.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.8
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• pp.5508-5512
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• 2015

Objective.: Sparganosis locations in humans are usually presented with a subcutaneous tissue of abdominal wall, chest, abdominal vicera and brain, but are rarely found in the breast. Methods. A case of sparganosis was confirmed by surgical excision of two parasites in a 76-year-old female patient present to a palpable mass in the right breast (presumed to have been sparganosis approximately 3 years ago). She had no history to direct ingestion of snakes or frogs, but had the history of drinking contaminated water. Mammography, ultrasonography, MRI, and FDG PET/CT imaging findings for patient were characteristic of sparganosis due to suspicion of breast cancer. Conclusions: The first route of infection in humans is drinking contaminated water. The second route is the ingestion of raw or partially cooked snakes or frogs. The third route is infected wound snake, frog muscle that attach to the case. However, only a few cases of drinking contaminated water have been reported in the country. Ultrasonography, MRI is known to be helpful for diagnosis of breast sparganosis. However, Mammography, ultrasonography, MRI, and FDG PET/CT for breast sparganosis is not reported present in the country. Reported the case and reviewed the related literature briefly.

• Proceedings of the KSMRM Conference
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• 2001.11a
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• pp.25-34
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• 2001

복부의 자기공명영상(Magnetic resonance imaging； MRI)은 주로 간 질환의 검사에서 다른 영상검사로 해결되지 않은 궁금점을 풀기 위한 보조적인 검사로 주로 사용하였으나, 최근 들어서는 병변의 발견 및 감별진단에 직접적인 검사로도 자주 이용하고 있으며, 담췌관 질환이나 위장관 검사 등에도 적용범위가 넓어지고 있다. 이는 그간의 하드웨어 및 소프트웨어상의 발달로 인해, 위장관 연동운동이나 호흡에 따른 인공물을 억제하면서도 해부학적인 세부구조는 자세하게 나타낼 수 있는 우수한 영상을 얻을 수 있음으로써 가능하게 되었다. 고속영상은 영상의 질을 우수하게 할 뿐 아니라, 검사시간을 단축시켜서 더 많은 환자를 검사할 수 있게 하고, 한자가 검사에 더 잘 적응할 수 있게 하여준다. 단발(single-shot)기법의 고속 T2강조영상은 담췌관이나 위장관등 그간 MRI를 적용하기 어려웠던 부위에 대한 검사가 가능하게 하였으며, 고속의 3차원 T1강조 펄스대열(pulse sequence)은 단면에 따른 오기록(misregistration)이나 운동인공물이 적으면서도, 향상된 다평면적인 영상구성을 얻을 수 있게 하였다. ［l］. 본 강좌에서는 최근 수년간 복부 MRI의 응용을 증가할 수 있게 한 영상장치 및 펄스대열의 발전과 최근 국내에 시판이 허용되어 사용이 증가되고 있는 새로운 간자기공명조영제에 관해서 살펴보고자 한다.