• Proceedings of the Korean Information Science Society Conference
• /
• 2002.10d
• /
• pp.607-609
• /
• 2002

본 논문은 흉부 전산화단층촬영 영상에서 폐 영역을 자동으로 분할하는 알고리즘과 폐결절을 자동으로 검출하는 알고리즘에 관한 연구 내용을 담고 있다. 폐 분할 알고리즘은 gray-level thresholding과 morphologic 영상 처리기법을 이용하였고, 폐결절 자동 검출 알고리즘은 추출된 결절 후보의 size, compactness, mean of gray level 값을 분석하여 혈관과 결절을 구분하였다. 개발한 폐결절 자동 검출 시스템은 실험한 영상에 포함된 폐결절 117개 중 55%인 64개를 검출하였고, 3.4 False Positive/section이었다.

• Proceedings of the Korean Society of Radiological Science
• /
• 1995.05a
• /
• pp.150-152
• /
• 1995

• Journal of the Korean Society of Radiology
• /
• v.82 no.2
• /
• pp.475-480
• /
• 2021

Xanthogranulomatous pyelonephritis (XGP) is a rare type of chronic bacterial nephritis, which rarely involves the invasion of adjacent organs or the formation of fistulas due to tissue-destructive granulomatous reactions. Although the invasions of various adjacent organs have been reported in several cases of XGP, MRI data on their features are limited. MRI has a better soft-tissue resolution than CT. Thus, it can identify the extent of extrarenal involvement in advanced XGP, and the findings can be used in treatment planning. Herein, we report a rare case of XGP with nephropleural fistula formation diagnosed using CT and MRI.

• Journal of the Korean Society of Radiology
• /
• v.8 no.6
• /
• pp.279-285
• /
• 2014

This study is to have dose reduction and minimization of excessive use of contrast medium in the pediatric cardiac computed tomography and to suggest the optimization plan to acquire the enhancement image of the 4 chambers at the same time by formulating scan delay time in empirical method with considering variables such as contrast medium injection velocity and cardiac approaching time. Quantitative, qualitative and dose assessment were carried out for 30 pediatric patients who had taken the cardiac examination. In conclusion, image enhancement in 4 chambers of the cardiac shows over 300 HU which is proper to pediatric cardiac reading by applying the empirical method with calculating scan delay time according to weight and contrast medium volume and injection velocity. Qualitative image assessments in confidence sharpness and noise have excellence qualitatively. Exposure dose to pediatrics also decreases precisely. Therefore this study is judged to take a important role of making optimization images with advantages of dose reduction and less side effects caused by it's excessive use in clinic.

• Proceedings of the KSLP Conference
• /
• 2003.11a
• /
• pp.162-163
• /
• 2003

후두의 기능으로는 하기도의 보호, 호흡, 발성, 흉강의 고정 등이 있다. 이 중 발성은 성대의 진동에 의한 성대음이 입술까지의 성도(vocal tract) 및 비강에서의 조음과 공명 과정을 거치면서 이루어진다. 후두 질환을 진단하는 방법으로 간접 후두경, 단순 X-선 검사, 굴곡성 후두경(flexible fiberscope), 후두원시경(telescope), 전산화 단층 촬영, 자기공명영상 등이 사용되어 왔다. (중략)

• Journal of radiological science and technology
• /
• v.26 no.2
• /
• pp.37-42
• /
• 2003

Purpose : Computed tomographic equipment is essential for diagnosis by means of radiation. With passage of time and development of science computed tomographic was developed time and again and in future examination by means of this equipment is expected to increase. In this connection these authors measured rate of scatter ray generation at front of lead glass for patients within control room of computed tomographic equipment room and outside of entrance door for exit and entrance of patients and attempted to ind out method for minimizing exposure to scatter ray. Material and Method : From November 2001 twenty five units of computed tomographic equipments which were already installed and operation by 13 general hospitals and university hospitals in Seoul were subjected to this study. As condition of photographing those recommended by manufacturer for measuring exposure to sauter ray was use. At the time objects used DALI CT Radiation Dose Test Phantom fot Head (${\oint}16\;cm$ Plexglas) and Phantom for Stomache(${\oint}32\;cm$ Plexglas) were used. For measurement of scatter ray Reader (Radiation Monitor Controller Model 2026) and G-M Survey were used to Survey Meter of Radical Corporation, model $20{\times}5-1800$, Electrometer/Ion Chamber, S/N 21740. Spots for measurement of scatter ray included front of lead glass for patients within control room of computed tomographic equipment room which is place where most of work by gradiographic personnel are carried out and is outside of entrance door for exit and entrance of patients and their guardians and at spot 100 cm off from isocenter at the time of scanning the object. The results : Work environment within computed tomography room which was installed and under operation by each hospital showed considerable difference depending on circumstances of pertinent hospitals and status of scatter ray was as follows. 1) From isocenter of computed tomographic equipment to lead glass for patients within control room average distance was 377 cm. At that time scatter ray showed diverse distribution from spot where no presence was detected to spot where about 100 mR/week was detected. But it met requirement of weekly tolerance $2.58{\times}10^{-5}\;C/kg$(100 mR/week). 2) From isocenter of computed tomographic equipment to outside of entrance door where patients and their guardians exit and enter was 439 cm in average, At that time scatter ray showed diverse distribution from spot where almost no presence was detected to spot with different level but in most of cases it satisfied requirement of weekly tolerance of $2.58{\times}10^{-6}\;C/kg$(100 mR/week). 3) At the time of scanning object amount of scatter ray at spot with 100 cm distance from isocenter showed considerable difference depending on equipments. Conclusion : Use of computed tomographic equipment as one for generation of radiation for diagnosis is increasing daily. Compared to other general X-ray photographing field of diagnosis is very high but there is a high possibility of exposure to radiation and scatter ray. To be free from scatter ray at computed tomographic equipment room even by slight degree it is essential to secure sufficient space and more effort should be exerted for development of variety of skills to enable maximum photographic image at minimum cost.

• Journal of the Korean Society of Radiology
• /
• v.82 no.5
• /
• pp.1334-1340
• /
• 2021

Amyloidosis has been reported to be associated with non-Hodgkin lymphoma. Amyloidosis and lymphoma can be related in two ways: lymphoma-associated systemic amyloidosis and peritumoral amyloidosis with lymphoma. We report a rare case of peritumoral amyloidosis in a patient with head and neck mucosa-associated lymphoid tissue lymphoma. On CT, the oropharyngeal mass showed an irregularly shaped soft-tissue density with multifocal amorphous calcifications and heterogeneous enhancement. On MRI, the mass showed heterogeneous low signal intensity on both T1- and T2-weighted images. On contrast-enhanced MR images, the mass showed good enhancement with several inner non-enhancing foci. Concurrent pathologies, such as peritumoral amyloidosis, should be considered when calcifications are noted in patients with pre-treatment lymphoma.

• Journal of the Korean Society of Radiology
• /
• v.16 no.7
• /
• pp.889-896
• /
• 2022

This study attempted to evaluate the usefulness of the air mattress by analyzing the subjective comfort of the patient due to the application of the air mattress to the table of computed tomography through a questionnaire and analyzing the change in image quality through quantitative and qualitative evaluation of the patient's clinical images. The subjects who participated in the study were 221 men and 229 women, and the age range was from 18 to 86. To evaluate the change in image quality, a total of 150 patients, 50 patients per group, were selected for quantitative evaluation, and 20 patients per group, a total of 60 patients were selected for qualitative evaluation. As a result of this study, the subjective comfort of patients increased due to air mattresses, and there was no difference in image quality as a result of quantitative and qualitative evaluation of clinical images. From the above results, it is believed that the air mattress can be usefully applied in a way that can increase the subjective comfort of the patient without any harm to the diagnostic image.

• Journal of the Korean Society of Radiology
• /
• v.84 no.4
• /
• pp.911-922
• /
• 2023

Purpose To compare small bowel distension and side effects between a diluted polyethylene glycol (PEG) solution and a low-density (0.1% w/v) barium sulfate suspension (LDBSS) for CT enterography (CTE) preparation. Materials and Methods Total 173 consecutive patients who underwent CTE were enrolled in this study. The LDBSS (1 L) was used in 50 patients, and the diluted iso-osmotic PEG solution (1 L) was used in 123 patients. Two blinded radiologists independently scored jejunal and ileal distensions on a 5-point scale. To compare side effects between the two groups, the patients reported whether they had immediate complications after the administration of the oral contrast media. Results For ileal and jejunal distension, the diluted PEG solution showed no difference from the LDBSS for either reader (ileum: reader 1, median, 4; 4, interquartile range, 3-4; 3-4, p = 0.997; reader 2, median, 4; 4, interquartile range, 3.3-4.0; 3-4, p = 0.064; jejunum: reader 1, median, 2; 2, interquartile range, 2-3; 2-3, p = 0.560; reader 2, median, 3; 2, interquartile range, 2-3; 2-3, p = 0.192). None of the patients complained of immediate complications following administration of either of the oral contrast media. Conclusion The diluted PEG solution showed comparable bowel distension compared to LDBSS and no immediate side effects; thus, it can be a useful alternative.

• Journal of the Korean Society of Radiology
• /
• v.17 no.3
• /
• pp.385-392
• /
• 2023

Caroli's disease is a fibrocystic liver disease. Autosomal recessive disorder is characterized by congenital multiple dilatation of the bile duct. Computerized tomography, magnetic resonance imaging, cholangiography and ultrasound are among the methods for diagnosing caroli disease. Computerized tomography is essential for detecting and distinguishing fibroplastic liver disease and is useful for determining intrahepatic bile duct dilatation. However, awareness of the possible side effects of using contrast mediums is necessary. A typical method of magnetic resonance cholangiography is used for magnetic resonance imaging. A non-invasive examination can reduce the pain of the patient, and the anatomical structure of the bile pancreatic duct and the presence or absence of lesions can be easily and quickly observed. Biliary contrast is an effective diagnostic method that can directly visualize various cystic dilatations throughout the enlarged bile duct. However, since this procedure is also an invasive procedure, it is recommended not for diagnosis but for treatment purposes. Ultrasonography can confirm similar findings to computerized tomography. The hepatic artery root is difficult to prove with conventional grayscale ultrasound. However, it is of clinical value in that it can not only describe dilated bile ducts with vascular roots in the tube but also easily identify color Doppler signals in the tube. With the development of video diagnostics, early diagnosis has become possible through computerized tomography, magnetic resonance imaging, cholangiography, and ultrasound. In order to further contribute to the development of video diagnostics so that long-term prognosis can be improved after treatment through early diagnosis, we examined what aspects of each test's caroli disease appear.