• Childhood Kidney Diseases
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• v.3 no.1
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• pp.57-63
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• 1999

Purpose : To evaluate the diagnostic significance of simultaneous examination of hematuria and proteinuria in the urinary mass screening for early detection ot incipient renal diseases. Method and Object : During the period of 4 months from August to December in 1997, we did urinary mass screening on students of first grade of high school (16 years aged group) nationwide together with Korean Association of Health(KAH). In the first screening test, Comber-10 $N^{(R)}$ M dipsticks were used to detect proteinuria, hematuria, pyuria and nitrite simultaneously. Total 26,508 students (16 years aged group) from 33 high schools in every province in Korea, respectively, complied to the urinary mass screening. After then, one high school in Seoul was selected to reveal the true incidence of incipient renal diseases among students who showed hematuria in the initial screening through intensive examinations. Those who had hematuria and/or proteinuria visited the Paik hospital, and underwent blood tests and ultrasonographic examinations. The results were evaluated. Results 1) The initial screening revealed that the prevalence of proteinuria, hematuria, pyuria and positive nitrite urine, were $0.73\%,\;2.69\%,\;0.23\%\;and\;0.03\%$, respectively. 2) The first urinary screening among 875 students from one high school in Seoul selected fir the second test showed proteinuria, hematuria, pyuria and positive nitrite urine, were $0.91\%,\;4.68\%,\;0.34\%\;and\;0\%$, respectively. a) Total 8 among 875 students showed proteinuria, but one of them had orthostatic proteinuria and those remaining 7 students had transient proteinuria. b) There were 41 students who had hematuria in the initial screening. Among 33 who complied the second test, only one student showed asymptomatic isolated hematuria and those remaining students were normal. Conclusion : 1) Because of high false positive hematuria rate in the urinary mass screening, it dosen't seem to be appropriate that hematuria screening using dipsticks be included in the urinary mass screening. 2) A unified organization is needed from the fret that so various results of urinary mass screening came out. 3) Positive rates of pyuria and nitrite were so low that validity of urinary mass screening for urinary tract infection needs more studies.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.3
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• pp.92-101
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• 2009

Purpose: Scintimammography is one of the screening tests for the early diagnosis of breast cancer. It has been widely accepted as very useful in assessing masses that have not been detected in breast scanning. This method is highly sensitive and specific with respect to the diagnosis of primary and relapsing breast cancer. It has some difficulties, however, in detecting tumors sized 1 cm and below due to the radioactivity around the breast and the geometrical structure of the equipment. The recent introduction of high-resolution Breast-specific Gamma Imaging (BSGI) has made it possible to more accurately discriminate between malignant and benign tumors than with any other test method. Thus, the possibility of an unnecessary biopsy being performed has decreased. The purpose of this study was to examine the diagnostic capacity of mammography, breast sonography, and scintimammography, which are used for the early diagnosis of known breast cancer, and of BSGI, and to evaluate the skillfulness of radiologists. Materials and Methods: The 53 volunteers participants who had no clinical manifestation of breast cancer underwent the BSGI in February 2009. In the BSGI procedure, scanning images were obtained from the craniocaudal projection (CC) and the mediolateral Oblique projection (MLO), as well as from the additional $80{\times}80$-matrix-sized views at various angles in the Present Time method, 10 minutes after the 25 mCi $^{99m}Tc$-MIBI was injected. Results: The results of the BSGI showed that two participants had masses in their breast tissue. As the results of the diagnosis of four participants were not clear, they were retested and the results of the second test were negative. The results of the clinical screening test for breast cancer showed that the sensitivity of BSGI, scintimammography, mammography, and breast sonography was 86.5%, 77.8%, 85~90%, and 66.7%, respectively, and that their specificity was 92.4%, 84.2%, 20~42%, and 68%, respectively. Conclusion: The autodiagnosis and breast cancer screening test are needed for the early diagnosis of breast cancer. It was not easy, however, to accurately determine the presence of a mass in the breast using the existing breast cancer screening test. The patients with unclear test findings were made to undergo a histologic biopsy for a more accurate diagnosis. It is expected that the BSGI can provide useful information for the early diagnosis of breast cancer and of primary breast cancer, and will reduce the performance of unnecessary biopsies because of its higher sensitivity and specificity than existing breast cancer screening tests.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.56.2-56.2
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• 2015

The KMTNet Supernovae Project utilizes the large $2^{\circ}{\times}2^{\circ}$ field of view of the three KMTNet telescopes to search and monitor supernovae, especially early ones, and other optical transients. A key component of the project is to build a data pipeline with a descent latency and an early alerting system that can handle the large volume of the data in an efficient and a prompt way, while minimizing false alarms, which casts a significant challenge to the software development. Here we present the current status of their development. The pipeline utilizes a difference image analysis technique to discover candidate transient sources after making correction of image distortion. In the early phase of the program, final selection of transient sources from candidates will mainly rely on multi-filter, multi-epoch and multi-site screening as well as human inspection, and an interactive web-based system is being developed for this purpose. Eventually, machine learning algorithms, based on the training set collected in the early phase, will be used to select true transient sources from candidates.

• Journal of Gastric Cancer
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• v.14 no.3
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• pp.211-214
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• 2014

We report our experience of a concurrent robot assisted distal gastrectomy and partial nephrectomy for synchronous early gastric cancer and renal cell carcinoma. A 55-year-old female patient was diagnosed with early gastric cancer on screening endoscopy. Abdominal computed tomography showed an incidental right renal cell carcinoma. Robot assisted distal gastrectomy was performed, followed by partial nephrectomy. The final pathological examination showed signet ring cell carcinoma within the lamina propria and renal cell carcinoma with negative resection margins. The patient showed no evidence of recurrence at 6-months. A robot-assisted combined operation could be a treatment option for early stages of synchronous malignancies.

• Korean Journal of Bronchoesophagology
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• v.17 no.1
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• pp.14-18
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• 2011

The diagnosis and treatment of early gastrointestinal cancers is the gastroenterologists' mission because of national cancer screening program in South Korea. The detection of early cancers is emphasized, because these were previously treated with surgical treatment can be currently cured with endoscopic treatment. Gastroenterologists who achieved at least on some level can make an exact diagnosis regardless of what type of endoscopy, but generally, there are some required conditions for an optimal diagnosis. First, clinically important lesions have to be detected easily. Second, the border and morphology of lesions have to be characterized easily. Third, lesions have to be diagnosed exactly. Precancers and early cancers are often subtle and can pose a challenge to gastroenterologists to visualize using standard white light endoscopy. The use of dye solutions aids the diagnosis of early gastrointestinal cancers, however, it is a quite cumbersome to use dye solutions all the time and the solution often bothers the exact observation by pooling into the depression or ulceration of the lesion. To overcome this weakness, newer endoscopes are now developed so called "image enhanced endoscopy" using optical and/or electronic methods such as narrow band imaging (NBI), autofluorescence imaging (AFI), i-scan, flexible spectral imaging color enhancement (FICE) and confocal endomicroscopy (CLE).

• Journal of Gastric Cancer
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• v.21 no.1
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• pp.4-15
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• 2021

Recently, endoscopic screening systems have enabled the diagnosis of gastric cancer in the early stages. Early gastric cancer (EGC) is typically characterized by a shallow invasion depth and small size, which can hinder localization of EGC tumors during laparoscopic surgery. Here, we review nine recently reported tumor localization methods for the laparoscopic resection of EGCs. Preoperative dye or blood tattooing has the disadvantage of spreading. Preoperative 3-dimensional computed tomography reconstruction is not performed in real time during laparoscopic gastrectomy. Thus, they are considered to have a low accuracy. Intraoperative portable abdominal radiography and intraoperative laparoscopic ultrasonography methods can provide real-time feedback, but these methods require expertise, and it can be difficult to define the clips in some gastric regions. Despite a few limitations, intraoperative gastrofibroscopy provides real-time feedback with high accuracy. The detection system using an endoscopic magnetic marking clip, fluorescent clip, and radio-frequency identification detection system clip is considered highly accurate and provides real-time feedback; we expect a commercial version of this setup to be available in the near future. However, there is not yet an easy method for accurate real-time detection. We hope that improved devices will soon be developed and used in clinical settings.

• The Korean Journal of Applied Statistics
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• v.22 no.4
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• pp.771-780
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• 2009

Cataract is the main cause of blindness and visual impairment, especially, age-related cataract accounts for about half of the 32 million cases of blindness worldwide. As the life expectancy and the expansion of the elderly population are increasing, the cases of cataract increase as well, which causes a serious economic and social problem throughout the country. However, the incidence of cataract can be reduced dramatically through early diagnosis and prevention. In this study, we developed a prediction model of cataracts for early diagnosis using hospital data of 3,237 subjects who received the screening test first and then later visited medical center for cataract check-ups cataract between 1994 and 2005. To develop the prediction model, we used random forests and compared the predictive performance of this model with other common discriminant models such as logistic regression, discriminant model, decision tree, naive Bayes, and two popular ensemble model, bagging and arcing. The accuracy of random forests was 67.16%, sensitivity was 72.28%, and main factors included in this model were age, diabetes, WBC, platelet, triglyceride, BMI and so on. The results showed that it could predict about 70% of cataract existence by screening test without any information from direct eye examination by ophthalmologist. We expect that our model may contribute to diagnose cataract and help preventing cataract in early stages.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.15 no.2
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• pp.78-86
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• 2015

Purpose: Homocystinuria (OMIM#236200) is a metabolic disease caused by mutation in the CBS gene. This study was conducted to identify the clinical features and prognosis of homocystinuria as well as to find out the CBS gene mutations of the six homocystinuria patients who were receiving treatment in the Pediatric Department at Soonchunhyang University Hospital. Methods: From January 1992 to March 2015, clinical, biochemical, and genetic analyses were performed retrospectively on the six patients diagnosed with classic homocystinuria at Soonchunhyang University Hospital. Results: A total of six patients were included in this study, including three who were diagnosed with homocystinuria at the mean age of $50{\pm}22.5$ days based on their abnormal newborn screening test results. The other three were diagnosed at the mean age of 7, when they visited the hospital for evaluation of developmental delay and lens dislocation. The group diagnosed at early infancy had normal cognitive function, but the other group had varying degrees of mental retardation. Major complications were found only in the group diagnosed after infancy. CBS gene mutation was found in all the patients, and they were all non-responsive to vitamin B6 treatment. At present, all patients' diets are controlled following a methionine-free formula and they are on medication with folic acid, betaine, pyridoxine, and methylcobalamin. Conclusion: Six homocystinuria patients were monitored for up to 23 years. The group diagnosed at early infancy exhibited no major complications. Therefore, early diagnosis is crucial in the prognosis, and homocystinuria must be included in the newborn screening program.

• Korean Journal of Plant Tissue Culture
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• v.27 no.2
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• pp.109-115
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• 2000

Effects of the heavy-ion ($^{14}$ N or $^{20}$ Ne) beam irradiation on the response of anthers, growth of calli, germination of seeds, and the early growth after the germination of tobacco (Nicotiana tabacum L. cv. BY-4) were investigated. Anthers precultured for 10 days before the irradiation became brown without callus or shoot induction over 20 Gy of $^{14}$ N and $^{20}$ Ne ion beam irradiation. Relative growth rate of the cultured calli was reduced by the irradiation and became brown significantly 2 weeks after the $^{14}$ N and $^{20}$ Ne ion beam irradiation over 50 Gy. The increased intensity of the heavy-ion ($^{14}$ N, $^{20}$ Ne) beam irradiation resulted in the delay of seed germination and the inhibition of the early growth both in water-treated and non-treated seeds before the irradiation. In addition, the heavy-ion beam irradiation to the imbibed seeds inhibited seed germination more than that to the non-imbibed seeds. The screening approach of non-imbibed seeds with heavy-ion beam irradiation using in vitro culture system was more useful than the filter-paper germination method in investigating the characteristics of heavy-ion beam-irradiated seed population and the screening of morphological variants at the early stage of the plant growth.

• Korean Journal of Radiology
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• v.19 no.6
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• pp.1179-1186
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• 2018

Objective: The purposes of this study were to evaluate size-specific dose estimate (SSDE) of low-dose CT (LDCT) in the Korean Lung Cancer Screening (K-LUCAS) project and to determine whether CT protocols from Western countries are appropriate for lung cancer screening in Korea. Materials and Methods: For participants (n = 256, four institutions) of K-LUCAS pilot study, volume CT dose index ($CTDI_{vol}$) using a 32-cm diameter reference phantom was compared with SSDE, which was recalculated from $CTDI_{vol}$ using size-dependent conversion factor (f-size) based on the body size, as described in the American Association of Physicists in Medicine Report 204. This comparison was subsequently assessed by body mass index (BMI) levels (underweight/normal vs. overweight/obese), and automatic exposure control (AEC) adaptation (yes/no). Results: Size-specific dose estimate was higher than $CTDI_{vol}$ ($2.22{\pm}0.75mGy$ vs. $1.67{\pm}0.60mGy$, p < 0.001), since the f-size was larger than 1.0 for all participants. The ratio of SSDE to $CTDI_{vol}$ was higher in lower BMI groups; 1.26, 1.37, 1.43, and 1.53 in the obese (n = 103), overweight (n = 70), normal (n = 75), and underweight (n = 4), respectively. The ratio of SSDE to $CTDI_{vol}$ was greater in standard-sized participants than in large-sized participants independent of AEC adaptation; with AEC, SSDE/$CTDI_{vol}$ in large- vs. standard-sized participants: $1.30{\pm}0.08$ vs. $1.44{\pm}0.08$ (p < 0.001) and without AEC, $1.32{\pm}0.08$ vs. $1.42{\pm}0.06$ (p < 0.001). Conclusion: Volume CT dose index based on a reference phantom underestimates radiation exposure of LDCT in standard-sized Korean participants. The optimal radiation dose limit needs to be verified for standard-sized Korean participants.