Publications by authors named "Jung Gi Im"

78 Publications

Spectrum of pleuropulmonary paragonimiasis: An analysis of 685 cases diagnosed over 22 years.

J Infect 2021 01 2;82(1):150-158. Epub 2020 Oct 2.

Department of Molecular Parasitology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 2066 Seobu-ro, Jangan-gu, Suwon 16419, Korea. Electronic address:

Objectives: Paragonimiasis is a global foodborne zoonosis. Overlapping clinical and imaging features with other lung pathologies hamper correct diagnosis and require differential diagnosis.

Methods: During 1982-2003, 49,012 samples were referred for immunodiagnosis of helminthiases. We detected paragonimiasis cases by enzyme-linked immunosorbent assay (ELISA). We assessed clinical, radiographical and laboratory characteristics, and diagnostic dilemmas associated with delayed diagnosis.

Results: We analyzed 685 pleuropulmonary paragonimiasis cases. ELISA-positive was 665. Eggs were detected in 50. Symptom duration correlated well with the appearance of chest radiographs; 359 pleural, 33 pleuroparenchymal, and 264 parenchymal lesions (P < 0.001). Twenty-nine had normal chest images. Eosinophilia, seen in 304, was common in pleural and pleuroparenchymal patients (P < 0.05). Chest pain and dyspnea were characteristic for pleurisy patients. Sputum (odds ratios [OR]: 6.79; 95% CI: 4.41-10.47), blood-tinged sputum (OR: 5.62; 95% CI: 3.75-8.42), and foul-odor (OR: 2.70; 95% CI: 1.42-5.16) were significant in parenchymal patients. Delayed diagnosis (119) for ≥ 25 weeks was attributed mainly to misdiagnosis as tuberculosis, malignancy, or chronic obstructive pulmonary disease (COPD) (OR: 111.75; 95% CI: 43.25-288.74).

Conclusions: Variable symptoms and radiographs of pleuropulmonary paragonimiasis depended on the stage of infection. Suspicion of tuberculosis, malignancy, or COPD was major cause of delayed diagnosis.
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http://dx.doi.org/10.1016/j.jinf.2020.09.037DOI Listing
January 2021

Inter-observer agreement in identifying traction bronchiectasis on computed tomography: its improvement with the use of the additional criteria for chronic fibrosing interstitial pneumonia.

Jpn J Radiol 2019 Nov 14;37(11):773-780. Epub 2019 Sep 14.

Division of Pulmonary Medicine, Nerima-Hikarigaoka Hospital, Tokyo, Japan.

Purpose: To assess inter-observer variability in identifying traction bronchiectasis on computed tomography (CT) using additional criteria for chronic fibrosing interstitial pneumonia.

Methods: Seven experts categorized CT image set representing 39 patients into three groups on the basis of the presence of traction bronchiectasis, using a three-point scale: 3-definitely/probably yes; 2-possibly yes; and 1-definitely/probably no. This scale served as a reference standard. The image set included cases of chronic fibrosing interstitial pneumonia, non-interstitial lung disease, and difficult-to-determine cases. Forty-eight observers similarly assessed the same image set, first according to the Fleischner Society definition, and second with additional criteria, in which traction bronchiectasis was observed exclusively in chronic fibrosing interstitial pneumonia. The agreement level between the reference standard and each observer's evaluation in each session was calculated using weighted kappa values which were compared between the two sessions using a paired t test.

Results: The mean weighted kappa value for all observers was significantly higher in the second reading session (mean 0.75) than in the first reading session (mean 0.62) (p < 0.001).

Conclusion: Inter-observer agreement in identifying traction bronchiectasis improves when using the additional criteria which specify chronic fibrosing interstitial pneumonia as the underlying disease.
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http://dx.doi.org/10.1007/s11604-019-00864-wDOI Listing
November 2019

Tree-in-Bud Pattern of Pulmonary Tuberculosis on Thin-Section CT: Pathological Implications.

Korean J Radiol 2018 Sep-Oct;19(5):859-865. Epub 2018 Aug 6.

University of Fukui, School of Medical Sciences, Bunkyo, Fukui-shi, Fukui 910-8507, Japan.

The "tree-in-bud-pattern" of images on thin-section lung CT is defined by centrilobular branching structures that resemble a budding tree. We investigated the pathological basis of the tree-in-bud lesion by reviewing the pathological specimens of bronchograms of normal lungs and contract radiographs of the post-mortem lungs manifesting active pulmonary tuberculosis. The tree portion corresponds to the intralobular inflammatory bronchiole, while the bud portion represents filling of inflammatory substances within alveolar ducts, which are larger than the corresponding bronchioles. Inflammatory bronchiole per se represents the "tree" (stem) and inflammatory alveolar ducts constitute the "buds" or clubbing. "Clusters of micronodules", seen on 7-mm thick post-mortem radiographs with tuberculosis proved to be clusters of tree-in-bud lesions within the three-dimensional space of secondary pulmonary lobule based on radiological/pathological correlation. None of the post-mortem lung specimens showed findings of lung parenchymal lymphatics involvement.
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http://dx.doi.org/10.3348/kjr.2018.19.5.859DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6082770PMC
April 2019

The optimum chest compression site with regard to heart failure demonstrated by computed tomography.

Am J Emerg Med 2017 Dec 13;35(12):1899-1906. Epub 2017 Jul 13.

Department of Radiology, Sheikh Khalifa Specialty Hospital, Ras Al Khaimah, United Arab Emirates.

Background: To determine the optimum chest compression site during cardiopulmonary resuscitation (CPR) with regard to heart failure (HF) by applying three-dimensional (3D) coordinates on computed tomography (CT).

Methods: This retrospective, cross-sectional study involved adults who underwent echocardiography and CT on the same day from 2007 to 2017. Incomplete CT images or information on HF, cardiac medication between echocardiography and CT, or thoracic abnormalities were excluded. Cases were checked whether they had HF through symptom/sign assessment, N-terminal pro-B type natriuretic peptide, and echocardiography. We set the xiphisternal joint's midpoint as the reference (0, 0, 0) to draw a 3D coordinate system, designating leftward, upward, and into-the-thorax directions as positive. The coordinate of the maximum LV diameter's midpoint (P_max.LV) was identified.

Results: Enrolled were 148 patients (63.0±15.1 years) with 87 females and 76 HF cases. P_max.LV of HF cases was located more leftwards, lower, and deeper than non-HF cases (5.69±0.98, -1.51±1.67, 5.76±1.09 cm vs. 5.00±0.83, -0.99±1.36, 5.25±0.71 cm, all p<0.05). Fewer HF cases had their LV compressed than non-HF cases (59.2% vs. 77.8%, p=0.025) when being compressed according to the current guidelines. The aorta (vs. LV) was compressed in 85.5% and 81.9% of HF and non-HF cases, respectively, at 3 cm above the xiphisternal joint. At 6cm above the joint, the highest allowable position according to the current guidelines, all victims would have their aorta compressed directly during CPR rather than the LV.

Conclusions: The lowest possible sternum just above the xiphisternal joint should be compressed especially for HF patients during CPR.
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http://dx.doi.org/10.1016/j.ajem.2017.07.041DOI Listing
December 2017

Outcomes of Esophageal Arterial Embolization for Treatment of Hemoptysis.

J Vasc Interv Radiol 2017 Feb 7;28(2):284-290. Epub 2016 Dec 7.

Department of Radiology, Sheikh Khalifa Specialty Hospital, Ras Al Khaimah, United Arab Emirates.

Purpose: To investigate safety and efficacy of esophageal arterial embolization (EAE) in addition to bronchial arterial embolization (BAE) for treatment of hemoptysis as well as the importance and characteristics of esophageal arteries in patients with hemoptysis.

Materials And Methods: Between January 2013 and December 2014, 20 patients (13 men and 7 women, mean age 58.4 y) underwent EAE in addition to BAE for hemoptysis. Retrospective review of patient records was performed to evaluate major causes of hemoptysis, treatment indications based on CT findings, esophageal angiography findings, and outcomes after embolization including clinical success rate and complications.

Results: Hemoptysis was caused by bronchiectasis (12 patients), tuberculosis (7 patients), and lobectomy (1 patient). CT showed lower lobe lung lesions in all (100%) patients. The esophageal arteries originated from the aorta between the carina and diaphragm (18 patients) or from the inferior phrenic arteries (2 patients) and were tortuous with longitudinal off-midline courses. Communications between the esophageal and the bronchial or inferior phrenic arteries were present in 12 patients. One patient who was treated using N-butyl cyanoacrylate developed dysphagia that resolved with medical treatment. Repeat BAE was performed in 2 patients 5 days and 20 days later, and the clinical success rate was 90% (18/20).

Conclusions: EAE in addition to BAE is safe in the treatment of hemoptysis and should be considered for lower lobe lesions.
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http://dx.doi.org/10.1016/j.jvir.2016.09.026DOI Listing
February 2017

Sequential morphological changes in follow-up CT of pulmonary mucormycosis.

Diagn Interv Radiol 2014 Jan-Feb;20(1):42-6

From the Department of Radiology (J.Y.C., C.M.P. e-mail: H.J.L., C.H.L., J.M.G. J.G.I.) Seoul National University College of Medicine, and Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Korea; the Department of Radiology (J.Y.C.), Korea University Ansan Hospital, Ansan, Korea.

Purpose: We aimed to describe the computed tomography (CT) features of pulmonary mucormycosis including sequential changes between follow-ups.

Materials And Methods: Between June 2001 and May 2011, five patients (three males and two females; median age, 43 years; age range, 13-73 years) who had been pathologically diagnosed with pulmonary mucormycosis constituted our study population. Their clinical and CT features including sequential changes over follow-ups were evaluated retrospectively.

Results: All patients were immunocompromised due to either hematologic diseases (n=3), diabetes mellitus (n=1), or steroid administration for autoimmune hepatitis (n=1). All patients had symptoms such as fever (n=5), tachycardia (n=1), or pleuritic chest pain (n=1) on admission. Regarding the clinical outcome after treatment, one patient died, and the remaining four recovered from the disease. In terms of initial CT features, the morphologies of pulmonary mucormycosis included a single mass (n=3), consolidation (n=1), or multiple masses (n=1). There were seven pulmonary lesions in total, 3-7 cm in size, which showed a CT halo sign (n=3), reversed-halo sign (n=2), or air-fluid levels (n=2). On follow-up CTs, the lesions of all patients contained necrosis. All three patients with a mass or masses with a CT halo sign on initial CT had a decreased surrounding halo followed by central necrosis, and the lesions gradually decreased in size on recovery.

Conclusion: Pulmonary mucormycosis usually manifests as a mass or masses with a halo or reversed-halo sign on the initial CT scan followed by a decreased extent of surrounding ground-glass opacities with the development of internal necrosis during follow-up.
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http://dx.doi.org/10.5152/dir.2013.13183DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4463253PMC
April 2015

Adaptive 4D volume perfusion CT of lung cancer: effects of computerized motion correction and the range of volume coverage on measurement reproducibility.

AJR Am J Roentgenol 2013 Jun;200(6):W603-9

Department of Radiology, Seoul National University Hospital, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea.

Objective: The purpose of this study was to determine whether measurement reproducibility can be improved using computerized motion correction and whole-tumor coverage in adaptive 4D perfusion CT of lung cancer.

Subjects And Methods: Perfusion CT covering the entire z-axis of a mass was performed of 40 patients with lung cancer. Each perfusion CT study was performed in 93.5 seconds and included 17 repeated dynamic CT scans obtained using the Adaptive 4D Spiral mode. Tumor blood flow (BF), blood volume (BV), and permeability were measured in four different manners: in the entire tumor (whole-tumor coverage) without the use of motion correction; in the entire tumor with motion correction; in a small volume of interest (VOI) of tumor without motion correction; and in a small VOI with motion correction. Intra- and interobserver reproducibility were assessed through Bland-Altman analyses.

Results: The 95% limits of intraobserver reproducibility for BF, BV, and permeability were as follows: -52.1% to 48.0%, -22.4% to 27.8%, and -33.2% to 38.5%, respectively, in the whole tumor without motion correction; -53.3% to 45.6%, -17.7% to 20.6%, and -31.5% to 37.0% in the whole tumor with motion correction; -107.8% to 97.4%, -98.3% to 93.7%, and -132.3% to 100.7% in a small VOI of tumor without motion correction; and -74.9% to 98.6%, -74.5% to 88.1%, and -109.8% to 114.1% in a small VOI with motion correction. The 95% limits of interobserver reproducibility for BF, BV, and permeability were as follows: -57.0% to 62.5%, -36.8% to 52.6%, and -47.7% to 66.0%, respectively, in the whole tumor without motion correction; -55.7% to 55.8%, -25.8% to 42.0%, and -35.3% to 46.7% in the whole tumor with motion correction; -146.6% to 165.1%, -117.1% to 137.7%, and -143.2% to 149.8% in a small VOI of tumor without motion correction; and -106.2% to 133.6%, -99.5% to 122.4%, and -108.6% to 170.0% in a small VOI of tumor with motion correction. Overall, the best reproducibility was obtained when measurements were obtained in the entire tumor (i.e., whole-tumor coverage) and when motion correction was used.

Conclusion: Measurement reproducibility of perfusion parameters improved when measurements in the entire tumor (i.e., whole-tumor coverage) were obtained and computerized motion correction was used. The best reproducibility in parameter values was obtained with motion correction and whole-tumor coverage.
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http://dx.doi.org/10.2214/AJR.12.9458DOI Listing
June 2013

A new classification of adenocarcinoma: what the radiologists need to know.

Diagn Interv Radiol 2012 Nov-Dec;18(6):519-26. Epub 2012 May 23.

Department of Radiology, Seoul National University Hospital, Seoul, Republic of Korea.

The International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society recently introduced a new classification of lung adenocarcinoma addressing the latest advances in oncology, molecular biology, pathology, radiology, and surgery of lung adenocarcinoma. In this classification, new uniform terminology and diagnostic criteria are described, including the introduction of adenocarcinoma in situ as a second preinvasive lesion, as well as the concept of minimally-invasive adenocarcinoma and new subtyping of invasive adenocarcinomas stratified according to predominant patterns. In addition, the previously widely-used term bronchioloalveolar carcinoma is no longer considered valid and has been recategorized. This classification also provides, for the first time, guidance for small biopsies and cytology specimens. This new classification has profound implications for radiology, as much investigation will be needed to correlate these newly introduced concepts (such as histologic subtypes) with radiologic features. Understanding the newly described concept of minimally-invasive adenocarcinoma will be essential in determining sublobar resection for adenocarcinomas. In this manuscript, we briefly review the new classification of lung adenocarcinoma and discuss its radiologic relevance to the reporting, biopsy, and future studies of adenocarcinoma.
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http://dx.doi.org/10.4261/1305-3825.DIR.5778-12.1DOI Listing
November 2013

Computed tomography features of extensively drug-resistant pulmonary tuberculosis in non-HIV-infected patients.

J Comput Assist Tomogr 2010 Jul;34(4):559-63

Department of Radiology, Seoul National University College of Medicine, and Institute of Radiation Medicine, Seoul National University Medical Research Center, Korea.

Objective: To describe the computed tomography (CT) findings of pulmonary extensively drug-resistant tuberculosis (XDR-TB) in non-HIV-infected patients and to compare them with those of non-XDR multidrug-resistant tuberculosis (MDR-TB).

Methods: Retrospective review of microbiological results and drug-susceptibility tests of 260 non-HIV-infected patients who had been diagnosed with pulmonary MDR-TB from 1994 to 2005 revealed that 47 patients had XDR-TB, whereas the other 213 patients had non-XDR MDR-TB. Twenty of the 47 XDR-TB patients and 85 of the 213 non-XDR MDR-TB patients with available CT examinations were included in this study. Two radiologists reviewed the CT studies in consensus for the presence and extent of micronodules, tree-in-bud appearance, lobular consolidation (<2 cm), consolidation, cavity, bronchiectasis, emphysema, pleural effusion, lymphadenopathy, bronchopleural fistula, and empyema. We then compared the CT features of XDR-TB with those of non-XDR MDR-TB.

Results: Micronodules and tree-in-bud appearance were the most frequent CT abnormalities and were seen in all XDR-TB patients (100%). Consolidations, cavities, bronchiectasis, and lobular consolidations were found in 85%, 85%, 80%, and 70% of XDR-TB patients, respectively. The extents of micronodules, tree-in-bud appearance, lobular consolidation, consolidation, cavity, bronchiectasis, and emphysema were 3.60, 3.55, 1.35, 1.85, 1.65, 1.45, and 0.25 lobes, respectively. Compared with non-XDR MDR-TB, XDR-TB showed a significantly larger extent of tree-in-bud appearance and consolidation (P < 0.05). With respect to other CT features, there were no significant differences between XDR-TB and non-XDR MDR-TB.

Conclusion: Computed tomography findings of pulmonary XDR-TB are similar to those of non-XDR MDR-TB; however, XDR-TB tends to have more extensive consolidation and tree-in-bud appearance.
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http://dx.doi.org/10.1097/RCT.0b013e3181d472bcDOI Listing
July 2010

Notes from the 2009 annual meeting of the Korean Society of Thoracic Radiology.

J Thorac Imaging 2011 Feb;26(1):W33-41

Department of Radiology, The Catholic University of Korea, College of Medicine, Seoul, Korea.

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http://dx.doi.org/10.1097/RTI.0b013e3181d44ccbDOI Listing
February 2011

A history of the Korean Society of Thoracic Radiology.

J Thorac Imaging 2010 Feb;25(1):21-3

Department of Radiology, Seoul St Mary's Hospital, The Catholic University of Korea, College of Medicine, 505 Banpo-dong, Seocho-gu, Seoul 137-701, Korea.

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http://dx.doi.org/10.1097/RTI.0b013e3181caa856DOI Listing
February 2010

Vision of the korean association of medical colleges.

Authors:
Jung-Gi Im

Korean J Med Educ 2009 Jun 30;21(2):95-6. Epub 2009 Jun 30.

President, Korean Association of Medical Colleges.

The Korean Association of Medical Colleges (KAMC) has launched as a corporate aggregate in August 2008, since the inauguration meeting as "Korean Association of Medical School Deans" 24 years before. The mission of KAMC is to be the representing agency of medical education in Korea, producing policies and strategies, suggesting and influencing government agencies related to medical education. The KAMC will consolidate its basic role and continue to expand its role as well; evaluation of basic medical education, representative of graduate medical education, policy making of medical manpower education system.
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http://dx.doi.org/10.3946/kjme.2009.21.2.95DOI Listing
June 2009

FN13762 murine breast cancer: region-by-region correlation of first-pass perfusion CT indexes with histologic vascular parameters.

Radiology 2009 Jun;251(3):721-30

Department of Radiology, Seoul National University College of Medicine, and Institute of Radiation Medicine, Seoul National University Medical Research Center, 101 Daehangno, Jongno-gu, Seoul 110-744, Korea.

Purpose: To investigate the correlation between first-pass perfusion computed tomographic (CT) indexes and histologic vascular parameters in FN13762 breast cancer in rats by using region-by-region correlation methods.

Materials And Methods: The Animal Care and Use Committee approved this study. FN13762 murine breast cancer cells were implanted in 14 female Fischer 344 rats, and first-pass perfusion CT was performed. CT perfusion maps depicting blood flow, blood volume, mean transit time (MTT), and permeability-surface area (PSA) product were generated by using commercial perfusion software. The entire tumor area was divided into six separate regions on perfusion maps, and the regional perfusion indexes were quantified. Histologic vascular parameters, including microvessel density (MVD), luminal vessel number, luminal vessel area, and luminal vessel perimeter, were measured in the histologic region corresponding to the perfusion maps. Correlation analysis was performed between regional tumor perfusion indexes and histologic vascular parameters of the corresponding tumor region. Additionally, mean perfusion values of the entire tumor were correlated with histologic vascular parameters of the hot spot within the tumor. Among 14 rats, four were excluded from the analysis, and results were based on a final total of 10 rats.

Results: In tumors, blood flow, blood volume, and PSA product were significantly higher and MTT was significantly shorter (P < .05 for all) than these values in normal neck muscles. At region-by-region correlation, regional blood flow (r = 0.476), blood volume (r = 0.348), and MTT (r = -0.506) were significantly correlated with MVD in the corresponding tumor region (P < .01 for all). After adjustment for biologic variability between rats, regional blood flow (r = 0.614), blood volume (r = 0.515), MTT (r = -0.524), and PSA product (r = 0.228) remained significantly correlated with MVD in the corresponding tumor region. Correlation analysis between CT perfusion indexes of the entire tumor and histologic vascular parameters of the hot spot did not show significant correlations (P > .05).

Conclusion: Regional blood flow, blood volume, and MTT are significantly correlated with MVD in the corresponding tumor region.
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http://dx.doi.org/10.1148/radiol.2513081215DOI Listing
June 2009

Notes from the 2008 annual meeting of the Korean Society of Thoracic Radiology.

J Thorac Imaging 2009 Feb;24(1):79-85

Department of Radiology, Chung-Ang University College of Medicine, Yongsan Hospital, Yongsan-gu, Korea.

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http://dx.doi.org/10.1097/RTI.0b013e3181953e7dDOI Listing
February 2009

Notes from the 2007 annual meeting of the Korean Society of Thoracic Radiology.

J Thorac Imaging 2009 Feb;24(1):73-8

Department of Radiology, Yonsei University College of Medicine, Seodamoon-gu, Seoul, Korea.

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http://dx.doi.org/10.1097/RTI.0b013e31819ebf2aDOI Listing
February 2009

Efficacy of computer-aided detection system and thin-slab maximum intensity projection technique in the detection of pulmonary nodules in patients with resected metastases.

Invest Radiol 2009 Feb;44(2):105-13

Department of Radiology, Seoul National University College of Medicine, Institute of Radiation Medicine, Seoul National University Medical Research Center, Seoul, Korea.

Objectives: To evaluate the efficacy of the computer-aided detection (CAD) system and thin-slab maximum intensity projection (MIP) technique in the detection of pulmonary nodules at multidetector computed tomography (CT) in patients who underwent metastatectomy.

Materials And Methods: This retrospective study was approved by the institutional review board and patients' informed consent was waived. Forty-nine consecutive patients who underwent pulmonary metastatectomy were enrolled. Four chest radiologists analyzed preoperative 1-mm section CT images and recorded the locus of each nodule candidate. Afterward, they reevaluated the images once using CAD software and once with thin-slab MIP given the results of 1-mm section CT alone. The reference standard for nodule presence was established by a consensus panel and pathologic records for malignant nodules.

Results: A total of 514 nodules were identified by a consensus panel. Of 212 nodules surgically removed, 121 nodules were malignant. The sensitivity of each observer in detecting malignant nodules with thin-section CT scans alone was 91%, 88%, 87%, and 86% for observers A- to D, respectively. With CAD, sensitivity increased significantly to 95%, 95%, 94%, and 95% (P< 0.05 for observer B-D), and using MIP increased to 94%, 96%, 91%, and 92% (P < 0.05 for observer B-D), respectively. There were no significant differences in sensitivity between CAD and MIP for the detection of malignant nodules. The average number of false-positive findings per patient was 0.8 with thin-section CT alone, 1.1 with CAD, and 1.4 with MIP.

Conclusions: In candidates for metastatectomy, reading with the aid of either CAD or MIP significantly improved the detection of malignant nodules compared with using thin-section CT alone.
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http://dx.doi.org/10.1097/RLI.0b013e318190fcfcDOI Listing
February 2009

Radiation dose modulation techniques in the multidetector CT era: from basics to practice.

Radiographics 2008 Sep-Oct;28(5):1451-9

Department of Radiology, Seoul National University College of Medicine and Institute of Radiation Medicine, Jongno-gu, Seoul 110-744, South Korea.

Radiation exposure to the patient has become a concern for the radiologist in the multidetector computed tomography (CT) era. With the introduction of faster multidetector CT scanners, various techniques have been developed to reduce the radiation dose to the patient; one method is automatic exposure control (AEC). AEC systems make use of different types of control, including patient-size AEC, z-axis AEC, rotational or angular AEC, or a combination of two or more of these types. AEC systems operate on the basis of several methods: standard deviation, noise index, reference milliamperage, and reference image. A clear understanding of how to use different AEC systems on different multidetector CT scanners will allow users to modulate radiation dose, reduce photon starvation artifacts, and maintain image quality throughout the body. Further development of AEC systems and their successful introduction into clinical practice will require user education and good communication between users and manufacturers.
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http://dx.doi.org/10.1148/rg.285075075DOI Listing
December 2008

A new method of measuring the amount of soft tissue in pulmonary ground-glass opacity nodules: a phantom study.

Korean J Radiol 2008 May-Jun;9(3):219-25

Department of Radiology, Seoul National University Bundang Hospital, Gyeonggi-do, Korea.

Objective: To devise a new method to measure the amount of soft tissue in pulmonary ground-glass opacity nodules, and to compare the use of this method with a previous volumetric measurement method by use of a phantom study.

Materials And Methods: Phantom nodules were prepared with material from fixed normal swine lung. Forty nodules, each with a diameter of 10 mm, were made with a variable mean attenuation. The reference-standard amount of soft tissue in the nodules was obtained by dividing the weight by the specific gravity. The imaging data on the phantom nodules were acquired with the use of a 16-channel multidetector CT scanner. The CT-measured amount of soft tissue of the nodules was calculated as follows: soft tissue amount = volume x (1 + mean attenuation value / 1,000). The relative percentage error (RPE) between the CT-measured amount of the soft tissue and the reference-standard amount of the soft tissue was also measured. The RPEs determined with use of the new method were compared with the RPEs determined with the current volumetric measurement method by the use of the paired t test.

Results: The CT-measured amount of soft tissue showed a strong correlation with the reference-standard amount of soft tissue (R(2) = 0.996, p < 0.01). The mean RPE of the CT-measured amount of soft tissue in the nodules was -7.79 +/- 1.88%. The mean RPE of the CT-measured volume was 114.78 +/- 51.02%, which was significantly greater than the RPE of the CT-measured amount of soft tissue (p < 0.01).

Conclusion: The amount of soft tissue measured by the use of CT reflects the reference-standard amount of soft tissue in the ground-glass opacity nodules much more accurately than does the use of the CT-measured volume.
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http://dx.doi.org/10.3348/kjr.2008.9.3.219DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2627253PMC
November 2008

Semiquantitative measurement of murine bleomycin-induced lung fibrosis in in vivo and postmortem conditions using microcomputed tomography: correlation with pathologic scores--initial results.

Invest Radiol 2008 Jun;43(6):453-60

Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine. Seoul, Korea.

Objective: To evaluate whether the semiquantification of lung inflammation and fibrosis in murine bleomycin-induced lung fibrosis using micro-computed tomography (micro-CT) in in vivo and postmortem conditions is feasible, and to correlate micro-CT and pathologic scores.

Materials And Methods: Bleomycin-induced lung fibrosis was created by intratracheally instilling 3 mg/kg of bleomycin into C57BL/6 mice. Mice were allocated randomly to 2-week, 4-week, and 8-week follow-up groups. In each group, in vivo and follow-up postmortem micro-CT were performed using a voxel size of 35 x 35 x 35 microm. Ground-glass opacity (GGO), consolidation, parenchymal lines, honeycombing, and peripheral bronchial dilatation were scored on micro-CT images in a semiquantitative fashion, whereas inflammation and fibrosis were scored histopathologically. The confidence levels of micro-CT findings were also scored. Correlations between micro-CT and pathologic findings were examined using Spearman rank correlation analysis, and differences between CT scores and confidence levels for in vivo and postmortem micro-CT were subjected to Wilcoxon signed rank testing. Agreements between in vivo and postmortem micro-CT scores were tested using weighted kappa statistics.

Results: Consolidation in vivo (r = 0.46) and at postmortem (r = 0.39) and GGO in vivo (r = 0.31) by micro-CT showed fair to moderate correlation with pathologic inflammation scores (P < 0.001). By in vivo and postmortem micro-CT, parenchymal lines (r = 0.72 vs. 0.83) showed good to excellent and peripheral bronchial dilatation (r = 0.47 vs. 0.68) showed moderate to good correlation with pathologic fibrosis scores (P < 0.001). For GGO, consolidation, peripheral bronchial dilatation, and parenchymal lines, fair to moderate agreement was obtained between in vivo and postmortem micro-CT. However, confidence levels for peripheral bronchial dilatation, parenchymal lines, and honeycombing were significantly higher by postmortem micro-CT (P < 0.001).

Conclusions: Micro-CT scores and pathologic scores were found to be well correlated by in vivo and postmortem micro-CT. Although agreements between in vivo and postmortem micro-CT were significant, the confidence levels for fibrosis-related CT findings were significantly higher by postmortem micro-CT.
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http://dx.doi.org/10.1097/RLI.0b013e31816900ecDOI Listing
June 2008

Pulmonary nodular ground-glass opacities in patients with extrapulmonary cancers: what is their clinical significance and how can we determine whether they are malignant or benign lesions?

Chest 2008 Jun 13;133(6):1402-1409. Epub 2008 Mar 13.

Departments of Radiology, Seoul National University College of Medicine, Seoul, South Korea.

Background: The clinical significance of pulmonary nodular ground-glass opacities (NGGOs) in patients with extrapulmonary cancers is not known, although there is an urgent need for study on this topic. The purpose of this study, therefore, was to investigate the clinical significance of pulmonary NGGOs in these patients, and to develop a computerized scheme to distinguish malignant from benign NGGOs.

Methods: Fifty-nine pathologically proven pulmonary NGGOs in 34 patients with a history of extrapulmonary cancer were studied. We reviewed the CT scan characteristics of NGGOs and the clinical features of these patients. Artificial neural networks (ANNs) were constructed and tested as a classifier distinguishing malignant from benign NGGOs. The performance of ANNs was evaluated with receiver operating characteristic analysis.

Results: Twenty-eight patients (82.4%) were determined to have malignancies. Forty NGGOs (67.8%) were diagnosed as malignancies (adenocarcinomas, 24; bronchioloalveolar carcinomas, 16). Among the rest of the NGGOs, 14 were atypical adenomatous hyperplasias, 4 were focal fibrosis, and 1 was an inflammatory nodule. There were no cases of metastasis appearing as NGGOs. Between malignant and benign NGGOs, there were significant differences in lesion size; the presence of internal solid portion; the size and proportion of the internal solid portion; the lesion margin; and the presence of bubble lucency, air bronchogram, or pleural retraction (p < 0.05). Using these characteristics, ANNs showed excellent accuracy (z value, 0.973) in discriminating malignant from benign NGGOs.

Conclusions: Pulmonary NGGOs in patients with extrapulmonary cancers tend to have high malignancy rates and are very often primary lung cancers. ANNs might be a useful tool in distinguishing malignant from benign NGGOs.
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http://dx.doi.org/10.1378/chest.07-2568DOI Listing
June 2008

Computer-aided detection in full-field digital mammography: sensitivity and reproducibility in serial examinations.

Radiology 2008 Jan;246(1):71-80

Department of Radiology, Konkuk University Hospital, Seoul, Korea.

Purpose: To retrospectively evaluate the sensitivity and reproducibility of a computer-aided detection (CAD) system applied to serial digital mammograms obtained in women with breast cancer, with histologic analysis as the reference standard.

Materials And Methods: This study was institutional review board approved, and patient informed consent was waived. A commercially available CAD system was applied to initial and follow-up digital mammograms obtained in 93 women with breast cancer (mean age, 52 years; age range, 32-81 years). The mean interval between mammographic examinations was 23 days (range, 7-58 days). There were 119 visible lesion components (70 masses, 49 microcalcifications). Sensitivity, false-positive mark rate, and reproducibility of the CAD system were evaluated for both sets of mammograms with the t test.

Results: Sensitivities of the CAD system at initial and follow-up digital mammography were 91% and 89%, respectively, for detection of masses. Sensitivity of the CAD system for detection of microcalcifications was 100% at both initial and follow-up digital mammography. Overall false-positive mark rates were 0.29 per image and 0.27 per image at initial and follow-up digital mammography, respectively. When craniocaudal and mediolateral oblique views were considered separately, sensitivities were 76% and 75%, respectively, for masses and 96% and 92%, respectively, for microcalcifications. The reproducibility of CAD marks was 80% for true-positive masses, 92% for true-positive microcalcifications, 9% for false-positive masses, and 8% for false-positive microcalcifications (P < .001).

Conclusion: The sensitivity of the CAD system was consistently high for detection of breast cancer on initial and short-term follow-up digital mammograms. Reproducibility was significantly higher for true-positive CAD marks than for false-positive CAD marks.

Supplemental Material: http://radiology.rsnajnls.org/cgi/content/full/246/1/71/DC1.
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http://dx.doi.org/10.1148/radiol.2461062072DOI Listing
January 2008

Notes from the 2006 annual meeting of the Korean Society of Thoracic Radiology.

J Thorac Imaging 2007 Nov;22(4):378-85

Department of Radiology, Chungnam National University School of Medicine, Taejon, Korea.

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http://dx.doi.org/10.1097/RTI.0b013e31815901fbDOI Listing
November 2007

Chest computed tomographic findings and clinical features of legionella pneumonia.

J Comput Assist Tomogr 2007 Nov-Dec;31(6):950-5

Department of Radiology, Seoul National University College of Medicine, Seoul, Korea.

Objective: To describe the chest radiographic and computed tomographic (CT) findings of legionella pneumonia.

Methods: Serial chest radiographs and CT scans obtained in 12 patients with serologically proven Legionella pneumophila pneumonia were retrospectively reviewed. Chest CT findings were analyzed with regard to patterns and distributions of pulmonary abnormalities.

Results: Nine of the 12 patients were in an immunocompromised state, that is, steroid therapy (n = 8) and myelodysplastic syndrome (n = 1), and 6 of the 8 steroid users were on high-dose steroid. All patients showed multilobar or multisegmental pulmonary infiltrates on CT scans. The CT findings were categorizable as; predominantly airspace consolidations (n = 6), mixed lesions with lobular consolidation and ground-glass opacity (GGO) (n = 3), and pure GGO lesions (n = 2). Five of the 6 patients on high-dose steroid therapy had lobar consolidations with (n = 4) or without a cavity (n = 1), and 1 patient had a mixed lesion.

Conclusions: The most common CT findings in legionella pneumonia were multilobar or multisegmental consolidation and GGO. Cavitary lobar consolidation occurred commonly in patients on high-dose steroid therapy.
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http://dx.doi.org/10.1097/RCT.0b013e31804b211dDOI Listing
January 2008

Serial CT findings of Paragonimus infested dogs and the Micro-CT findings of the worm cysts.

Korean J Radiol 2007 Sep-Oct;8(5):372-81

Department of Radiology and the Institute of Radiation Medicine, Seoul National University College of Medicine, Seoul, Korea.

Objective: To investigate the serial CT findings of Paragonimus westermani infected dogs and the microscopic structures of the worm cysts using Micro-CT.

Materials And Methods: This study was approved by the committee on animal research at our institution. Fifteen dogs infected with P. westermani underwent serial contrast-enhanced CT scans at pre-infection, after 10 days of infection, and monthly thereafter until six months for determining the radiologic-pathologic correlation. Three dogs (one dog each time) were sacrificed at 1, 3 and 6 months, respectively. After fixation of the lungs, both multi-detector CT and Micro-CT were performed for examining the worm cysts.

Results: The initial findings were pleural effusion and/or subpleural ground-glass opacities or linear opacities at day 10. At day 30, subpleural and peribronchial nodules appeared with hydropneumothorax and abdominal or chest wall air bubbles. Cavitary change and bronchial dilatation began to be seen on CT scan at day 30 and this was mostly seen together with mediastinal lymphadenopathy at day 60. Thereafter, subpleural ground-glass opacities and nodules with or without cavitary changes were persistently observed until day 180. After cavitary change of the nodules, the migratory features of the subpleural or peribronchial nodules were seen on all the serial CT scans. Micro-CT showed that the cyst wall contained dilated interconnected tubular structures, which had communications with the cavity and the adjacent distal bronchus.

Conclusion: The CT findings of paragonimiasis depend on the migratory stage of the worms. The worm cyst can have numerous interconnected tubular channels within its own wall and these channels have connections with the cavity and the adjacent distal bronchus.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2626818PMC
http://dx.doi.org/10.3348/kjr.2007.8.5.372DOI Listing
December 2007

Gefitinib-induced pneumonitis in non-small cell lung cancer: radiological and clinical findings in five patients.

Clin Imaging 2007 Sep-Oct;31(5):306-12

Department of Radiology, Seoul National University College of Medicine, Seoul 110-744, South Korea.

Purpose: The objective of this study was to describe the radiological and clinical features of gefitinib-induced pneumonitis in non-small cell lung cancer (NSCLC).

Materials And Methods: Five patients who suffered dyspnea after gefitinib treatment were selected. Chest radiographs and computed tomography (CT) findings, along with clinical course, were evaluated.

Results: Patients complained of subacute dyspnea and hypoxia. Three patients improved after discontinuation of gefitinib, while remaining two showed no response. Unilateral or bilateral ground glass opacity was observed on chest radiographs and CT.

Conclusion: Radiological findings of gefitinib-induced pneumonitis were nonspecific, but radiologists should be aware of this adverse reaction, which can appear during the treatment in NSCLC patients.
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http://dx.doi.org/10.1016/j.clinimag.2007.04.023DOI Listing
December 2007

Smoking-related emphysema and interstitial lung diseases.

J Thorac Imaging 2007 Aug;22(3):286-91

Department of Radiology, Vancouver General Hospital, JPP South, 899 West 12th Ave, Vancouver BC V5Z 1M9, Canada.

Smoking-related illnesses contribute to a large number of deaths in the industrialized world and their treatment comprises a substantial percentage of total healthcare dollars. The most common and most well-known smoking-related illnesses include chronic obstructive pulmonary disease, bronchogenic carcinoma, and ischemic heart disease. However, the role of cigarette smoking in the pathogenesis of other lung diseases is becoming increasingly apparent. Knowledge of both the histologic and radiographic manifestations of smoking-related lung disease is important to the radiologist as imaging findings can be nonspecific. Finally, correlation of imaging and clinical information may obviate the need for open lung biopsy.
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http://dx.doi.org/10.1097/01.rti.0000213585.06602.08DOI Listing
August 2007

Comparison of observer performance on soft-copy reading of digital chest radiographs: high resolution liquid-crystal display monitors versus cathode-ray tube monitors.

Eur J Radiol 2008 Apr 6;66(1):13-8. Epub 2007 Aug 6.

Department of Radiology and Clinical Research Institute, Seoul National University Hospital and the Institute of Radiation Medicine, Seoul National University Medical Research Center, Republic of Korea.

The purpose of this study is to compare observer performance for detection of abnormalities on chest radiographs with 5-megapixel resolution liquid-crystal displays (LCD) and 5-megapixel resolution cathode-ray tube (CRT) monitors under bright and subdued ambient light conditions. Six radiologists reviewed a total of 254 digital chest radiographs under four different conditions with a combination of two types of monitors (a 5-megapixel resolution LCD and a 5-megapixel resolution CRT monitor) and with two types of ambient light (460 and 50 lux). The abnormalities analyzed were nodules, pneumothorax and interstitial lung disease. For each reader, the detection performance using 5-megapixel LCD and 5-megapixel CRT monitors under bright and subdued ambient light conditions were compared using multi-case and multi-modality ROC analysis. For each type of ambient light, the average detection performance with the two types of monitors was also compared. For each reader, the observer performance of 5-megapixel LCD and 5-megapixel CRT monitors, under both bright and subdued ambient light conditions, showed no significant statistical differences for detecting nodules, pneumothorax and interstitial lung disease. In addition, there was no significant statistical difference in the average performance when the two monitor displays, under both bright and subdued ambient light conditions, were compared.
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http://dx.doi.org/10.1016/j.ejrad.2007.05.023DOI Listing
April 2008