1.Comparative Study between Ultrahigh Spatial Frequency Algorithm and High Spatial Frequency Algorithm in High-Resolution CT of the Lungs.
Yu Whan OH ; Jung Hyuk KIM ; Won Hyuck SUH
Journal of the Korean Radiological Society 1994;30(1):105-111
PURPOSE: To date, the high spatial frequency algorithm (HSFA) which reduces image smoothing and increases spatial resolution has been used for the evaluation of parenchymal lung diseases in thin-section high-resolution CT. In this study, we compared the ultrahigh spatial frequency algorithm (UHSFA) with the high spatial frequency algorithm in the assessment of thin section images of the lung parenchyma. METHODS AND MATERIALS: Three radiologists compared the UHSFA and HSFA on identical CT images in a line-pair resolution phantom, one lung specimen, 2 patients with normal lung and 18 patients with abnormal lung parenchyma. RESULTS: Scanning of a line-pair resolution phantom demonstrated no difference in resolution between two techniques but it showed that outer lines of the line pairs with maximal resolution looked thicker on UHSFA than those on HSFA. Lung parenchymal detail with UHSFA was judged equal or superior to HSFA in 95% of images. Lung parenchymal sharpness was improved with UHSFA in all images. Although UHSFA resulted in an increase in visible noise, observers did not found that image noise interfered with image interpretation. The visual CT attenuation of normal lung parenchyma is minimally increased in images with HSFA. The overall visual preference of the images reconstructed on UHSFA was considered equal to or greater than that of those reconstructed on HSFA in 78% of images. CONCLUSION: The ultrahigh spatial frequency algorithm improved the overall visual quality of the images in pulmonary parenchymal high-resolution CT.
Humans
;
Lung Diseases
;
Lung*
;
Noise
2.Acute Interstitial Pneumonia: HRCT Findings in Five Patients.
Eun Young KANG ; Yu Whan OH ; Won Hyuck SUH
Journal of the Korean Radiological Society 1995;33(5):745-750
PURPOSE: To describe HRCT findings in five patients with pathologically proved acute interstitial pneumonia MATERIALS AND METHODS: This study included 5 patients with pathological and clinical diagnosis of acute interstitial pneumonia. Mean age of the patients was 40(range, 31-53 years). CT scans were reviewed by two chest radiologists retrospectively. CT scans were assessed for the presence and distribution of ground-glass attenuation, air-space consolidation, interlobular septal thickening, honeycombing, and pleural effusion. RESULTS: The area of ground-glass attenuation and air-space consolidation were seen at HRCT in all 5 patients. These lesions were distributed diffusely in both lungs, but involved predominantly subpleural lungs in 2 patients and posterior lungs in 3 patients. Three patients had mild interlobular septal thickening. None of them showed honeycombing. Three of the 5 patients died within 52 days of initial manifestation. CONCLUSION: Acute interstitial pneumonia differs from the more chronic form of idiopathic interstitial pneumonia in their HRCT findings.
Diagnosis
;
Humans
;
Idiopathic Interstitial Pneumonias
;
Lung
;
Lung Diseases, Interstitial*
;
Pleural Effusion
;
Retrospective Studies
;
Thorax
;
Tomography, X-Ray Computed
3.Plexiform Neurofibromatosis of the Mediastinum: CT Findings.
Chul Joong KIM ; Yu Whan OH ; Won Hyuck SUH ; Min Jin LEE ; Yung Suk LEE
Journal of the Korean Radiological Society 1994;31(5):883-887
PURPOSE: To evaluate the findings and the role of CT in plexiform neuro-fibromatosis of the mediastinum. MATERIALS AND METHODS: We retropectively reviewed the CT scans of five patients with plexiform neurofibromatosis of the mediastinum. The CT scans were reviewed with attention to the distribution of the lesions, appearance and attenuation of mediastinal lesions, enhancement pattern after intravenous contrast infusion and associated findingssuch as intercostal neurofibroma. RESULTS: In all five patients CT scans demonstrated fusiform low attenuated masses which were oriented longitudinally and extended over multiple contiguous scans along the distribution of major mediastinal nerves. In four patients, mediastinal lesions appeared infiltrative, obliterating adjacent mediastinal fat plane. One patient had well defined fusiform masses along the major mediastinal nerves. Postcontrast enhanced CT scans revealed slight central enhancement in two patient and no contrast enhancement in three patients. Associated findings such as neurofibromas of intercostal nerves and sympathetic trunk, or subcutaneous neurofibromas were detected on CTscans in all five patients. CONCLUSION: Characteristic CT findings of low attenuation masses along the major mediastinal nerves are helpful to differentiate plexiform neurofibromatosis from mediastinal lymphadenopathy and to prevent from misreading as a malignant disease.
Humans
;
Intercostal Nerves
;
Lymphatic Diseases
;
Mediastinum*
;
Neurofibroma
;
Neurofibromatoses*
;
Tomography, X-Ray Computed
4.High-Resolution CT Findings in Swyer-James Syndrome.
Kyoo Byung CHUNG ; Yu Whan OH ; Jung Hyuk KIM ; Won Hyuck SUH
Journal of the Korean Radiological Society 1994;31(5):857-862
PURPOSE: The purpose of this study was to evaluate the high-resolution CT features of Swyer-James syndrome with special attention to the airway lesions and to determine the clinical utility of high-resolution CT compared with that of chest radiography. MATERIALS AND METHODS: In seven patients with Swyer-James syndrome, we retrospectively reviewed chest radiographs obtained during inspiration and expiration and high-resolution CT scans obtained in inspiration. The high-resolution CT appearance was evaluated and compared with that of chest radiography. RESULTS: On both chest radiographs and high-resolution CT, the affected lung volume was relatively diminished in four patients and normal in three patients. In all seven patients, chest readiographs showed hyperlucency of the lung which was unilateral in four and bilateral in three patients. Unilateral small hilum was seen in six patients and bronchiectasis was demonstrated in one patient on chest radiographs. The hyperlucent lung volume was not diminished on expiratory radiographs in all seven patients. In all patients, high-resolution CT demonstrated low attenuation regions of the lung either bilaterally(n=5) or unilaterally(n=2). Pulmonary vessels were markedly decreased in size and number in the lung parenchyma with low attenuation. Six patients had bronchiectasis on high-resolution CT, which were cylindrical or varicose in five and cystic in one. Bronchiolectasis was observed in three patients on high-resolution CT. CONCLUSION: The high-resolution CT findings are characteristic of Swyer-James syndrome. High-resolution CT is more sensitive than chest radiography in detecting regions of low attenuation and bronchiectasis and may be useful for the diagnosis of Swyer-James syndrome. Our results suggest that bronchiectasis is a frequently associated airway lesion of Swyer-James syndrome and bronchiolectasis may be associated in some cases.
Bronchiectasis
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Diagnosis
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Humans
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Lung
;
Lung, Hyperlucent*
;
Radiography
;
Radiography, Thoracic
;
Retrospective Studies
;
Thorax
;
Tomography, X-Ray Computed
5.Differntiation between Endobronchial Tuberculosis and Bronchogenic Carcinoma Associated with Atelectasis or Obstructive Pneumonitis: CT Evaluation.
Yu Whan OH ; Jung Hyuk KIM ; Hwan Hoon CHUNG ; Kyeong Ah KIM
Journal of the Korean Radiological Society 1995;33(4):537-543
PURPOSE: Endobronchial tuberculosis and bronchogenic cancer are common causes of atelectasis or obstructive pneumonitis in Korea. Differntiation between endobronchial tuberculosis and bronchogenic carcinoma is important for the treatment and prognosis but it is sometimes difficult to differentiate these two lesions with radiologic examinations. The purpose of this study was to find the differential points between endobronchial tuberculosis and bronchogenic carcinoma associated with atelectasis or obstructive pneumonitis. MATERIALS AND METHODS: Forty patients in whom atelectasis or obstructive pneumonitis was detected on chest radiographs comprised the study. A definite mass opacity was not observed on chest radiographs in all patients. In these patients, the causes of obstruction were endobronchial tuberculosis (n=20) and bronchogenic cancer (n=20) which were microbiologically or pathologically confirmed. RESULTS: Double obstructive lesions were more frequently found in endobronchial tuberculosis (8/20) than in bronchogenic cancer (1/20). Multiple calcifications along the bronchial wall and severe distortion of bronchi were observed only in endobronchial tuberculosis (4/20) and associated low density mass at obstruction site was only observed in bronchogenic cancer (6/20). Bronchial dilatation (11/20) and parenchymal calcifications (14/20) distal to obstruction site, air containing bronchogram at post obstructive bronchus (14/20) were more frequently found in endobronchial tuberculosis. Contour bulging at obstruction site (14/20), and only mucus bronchogram at post obstructive bronchus (14/20) were more frequently found in bronchogenic carcinoma. CONCLUSION: In patients with atelectasis or obstructive pneumonitis, endobronchial tuberculosis is characterized by double obstructive lesion, multiple calcifications at the bronchial wall, and severe distortion of the bronchi. Endobronchial carcinoma is characterized by a low density mass at the obstructive site.
Bronchi
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Carcinoma, Bronchogenic*
;
Dilatation
;
Humans
;
Korea
;
Mucus
;
Pneumonia*
;
Prognosis
;
Pulmonary Atelectasis*
;
Radiography, Thoracic
;
Tuberculosis*
6.Radiologic Approach to the Idiopathic Interstitial Pneumonias.
Korean Journal of Medicine 2013;84(4):489-497
Idiopathic interstitial pneumonias (IIP), a heterogeneous group of diffuse parenchymal lung diseases, include seven clinicopathologic entities: idiopathic pulmonary fibrosis (IPF), nonspecific interstitial pneumonia (NSIP), cryptogenic organizing pneumonia (COP), acute interstitial pneumonia (AIP), respiratory bronchiolitis (RB)-associated interstitial lung disease (ILD), desquamative interstitial pneumonia (DIP), and lymphoid interstitial pneumonia (LIP). Each of these entities has a typical histologic pattern that correlates well with imaging features. Thus, imaging plays an essential role in classifying and differentiating this group of diseases. The characteristic HRCT findings of IPF are reticular opacity with honeycombing and traction bronchiectasis in a predominantly basal and peripheral distribution. NSIP manifests as basal ground-glass opacity and reticular opacity. Honeycombing is rare. COP is characterized by patchy peripheral or peribronchovascular consolidation. AIP appears as extensive, mixed ground-glass opacity and consolidation. RB-ILD and DIP are smoking-related diseases associated with CT features of poorly defined centrilobular nodules and ground-glass opacity. LIP is a rare disease characterized by ground-glass opacity sometimes associated with perivascular cysts. Although some of idiopathic interstitial pneumonias may show diagnostic CT features, the final diagnosis of IIPs is usually made by means of evaluation of all the combined clinical, radiologic, and pathologic findings.
Bronchiectasis
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Bronchiolitis
;
Cryptogenic Organizing Pneumonia
;
Idiopathic Interstitial Pneumonias
;
Idiopathic Pulmonary Fibrosis
;
Lip
;
Lung Diseases, Interstitial
;
Rare Diseases
;
Traction
7.Significace of Screening Mammography in the Detection of Breast Diseases.
Kyoung Ah KIM ; Soo Youn HAM ; Kyoo Byung CHUNG ; Yu Whan OH ; Hong In KIM
Journal of the Korean Radiological Society 1995;32(2):343-346
PURPOSE: To evaluate the clinical significance of the screening mammography in the detection of the breast diseases, especially breast carcinoma. MATERIALS AND METHODS: We analyzed 1,800 cases of mammography retrospectively. The mammography was done as a part of routine check in Health Counselling Center, Korea University Medical Center, during 9 months from November 1993 to July 1994. The age range was from 23 years to 76 years, mean 49.8 years, and the largest age group was 6th decade(31.4%). According to the mammographic findings, we divided the subjects into three groups; normal group, abnormal group in need of follow up study, abnormal group requiring biopsy. RESULT: On mammography, the normal group consisted of 1,534 cases(85%), and the abnormal group consisted of 266 cases(15%). The abnormal findings were benign-looking calcification(n=140), fibroadeno ma (n=29), fibrocystic changes (n=27), cyst(n=23), malignant lesion(n=15), lipoma(n=7), and others. In four of 15 cases, which were suspected to be malignant on mammograms, breast carcinoma was confirmed pathologically. In four cases of breast carcinoma, one was under 40 and the other 3 were over 50 years of age. All of the breast cancers were under 3cm in size, and the mammographic findings of breast cancer included spiculated margin(n=3), parenchymal disortion(n=3), malignant calcification(n=2) and enlarged axillary node (n=l). CONCLUSION: Screening mammogram is helpful for early detection of non-palpable breast cancer, especially for women over 50 years of age.
Academic Medical Centers
;
Biopsy
;
Breast Diseases*
;
Breast Neoplasms
;
Breast*
;
Female
;
Follow-Up Studies
;
Humans
;
Korea
;
Mammography*
;
Mass Screening*
;
Retrospective Studies
8.Benign Mass-like Lesions Associated with Chronic Tuberculous Empyema: CT Findings in 9 Patients.
Kyeong Ah KIM ; Yu Whan OH ; Jung Hyuck KIM
Journal of the Korean Radiological Society 1996;34(3):387-390
PURPOSE: To present CT findings of benign mass-like nodular lesions associated with chronic tuberculousempyema. MATERIALS AND METHODS: We retrospectively reviewed the CT scans of nine patients with mass-like lesions associated with chronic tuberculous empyema, which were pathologically (operation=4, US-guided biopsy=3) or clinically (n=2) confirmed as benign lesions. Shape, number, size, presence of calcification and enhancement pattern of mass-like lesions were assessed. RESULTS: In all patients, chest CT showed unilateral calcified pleural thickening, with mass-like nodular lesions. Fluid within the pleural cavity was observed in eight patients. CT findings of mass-like lesions were multiple and nodular (n=9). Calcification was demonstrated within the lesions in four patients. In each case, the size of the largest nodules was 1-3cm in diameter. In contrast, CTshowed mild (n=6) to moderate (n=2) enhancement compared with adjacent muscles. The pathologic results ofmass-like lesions were chronic inflammation (n=3) and necrosis (n=4). CONCLUSION: Benign mass-like lesions associated with chronic tuberculous empyema appeared as multiple nodules varying in size from 1 to 3cm in diamter, with slight enhancement.
Empyema, Tuberculous*
;
Humans
;
Inflammation
;
Muscles
;
Necrosis
;
Pleural Cavity
;
Retrospective Studies
;
Tomography, X-Ray Computed
;
Tuberculosis, Pulmonary
9.Idiopathic Pulmonary Fibrosis with Coexisting Emphysema: High-Resolution CT and Clinical Correlation.
Eun Young KANG ; Kyeong Ah KIM ; Yu Whan OH ; Jae Jeong SHIM ; Kyung Ho KANG
Journal of the Korean Radiological Society 1997;36(5):761-766
PURPOSE: To correlate high-resolution CT (HRCT) findings with smoking history and pulmonary function test (PFT) in patients with idiopathic pulmonary fibrosis (IPF) with or without coexisting emphysema. MATERIALS AND METHODS: The study included 24 patients who had undergone HRCT and in whom IPF had been confirmed pathologically (n=7) and clinically (n=17). The patients included 19 men and 5 women aged between from 44 and 78 (mean 59) years. HRCT findings were reviewed by two radiologists and assessed for the presence and extent of emphysema (CT emphysema score ; CES) and honeycombing (CT honeycombing score ; CHS). CES and CHS were retrospectively correlated with smoking status and pulmonary function test. RESULTS: Evidence of emphysema was seen on HRCT in 20 of 24 patients with IPF (83 %). CES was 14.3 and CHS was 18.1 in smokers with IPF, as compared with 1.8 and 6.7 in nonsmokers (p < 0.01). Pulmonary function tests showed lower percent predicted FEV1 (69.3 %), FVC (64.7 %), TLC(73.7 %), and RV (77.3 %), a lower percent predicted diffusing capacity of carbon monoxide (58.2%), and normal FEV1/FVC (99.1%). The pulmonary function test in smokers showed higher TLC and RV than in nonsmokers. Eight of nine patients whose CES was higher than their CHS, as seen on HRCT, were smokers and had a smoking history of 33.1 pack-years. Seven of 15 whose CHS was higher than their CES were smokers and had a smoking history of 16.8 pack-years. In patients with a higher CES than CHS pulmonary function test results showed normal TLC (85 %) and RV (100.7%) ; this contrasted with decreased TLC (72 %) and RV (68 %) in patients whose CHS was higher than their CES. CONCLUSION: Emphysema is a frequently associated finding in patients with IPF, as seen on HRCT, and emphysema is more frequent and extensive in smokers with IPF than non-smokers. HRCT is useful for detecting emphysema in patients with IPF, and the extent of emphysema on HRCT correlates with the results of the pulmonary function test and smoking status.
Carbon Monoxide
;
Emphysema*
;
Female
;
Humans
;
Idiopathic Pulmonary Fibrosis*
;
Male
;
Respiratory Function Tests
;
Retrospective Studies
;
Smoke
;
Smoking
10.Effect of the High-Pitch Mode in Dual-Source Computed Tomography on the Accuracy of Three-Dimensional Volumetry of Solid Pulmonary Nodules: A Phantom Study.
Sung Ho HWANG ; Yu Whan OH ; Soo Youn HAM ; Eun Young KANG ; Ki Yeol LEE
Korean Journal of Radiology 2015;16(3):641-647
OBJECTIVE: To evaluate the influence of high-pitch mode (HPM) in dual-source computed tomography (DSCT) on the accuracy of three-dimensional (3D) volumetry for solid pulmonary nodules. MATERIALS AND METHODS: A lung phantom implanted with 45 solid pulmonary nodules (n = 15 for each of 4-mm, 6-mm, and 8-mm in diameter) was scanned twice, first in conventional pitch mode (CPM) and then in HPM using DSCT. The relative percentage volume errors (RPEs) of 3D volumetry were compared between the HPM and CPM. In addition, the intermode volume variability (IVV) of 3D volumetry was calculated. RESULTS: In the measurement of the 6-mm and 8-mm nodules, there was no significant difference in RPE (p > 0.05, respectively) between the CPM and HPM (IVVs of 1.2 +/- 0.9%, and 1.7 +/- 1.5%, respectively). In the measurement of the 4-mm nodules, the mean RPE in the HPM (35.1 +/- 7.4%) was significantly greater (p < 0.01) than that in the CPM (18.4 +/- 5.3%), with an IVV of 13.1 +/- 6.6%. However, the IVVs were in an acceptable range (< 25%), regardless of nodule size. CONCLUSION: The accuracy of 3D volumetry with HPM for solid pulmonary nodule is comparable to that with CPM. However, the use of HPM may adversely affect the accuracy of 3D volumetry for smaller (< 5 mm in diameter) nodule.
Humans
;
Imaging, Three-Dimensional/instrumentation/*methods
;
Lung/radiography
;
Lung Neoplasms/*radiography
;
Multiple Pulmonary Nodules/*radiography
;
Phantoms, Imaging
;
Solitary Pulmonary Nodule/*radiography
;
Tomography, X-Ray Computed/instrumentation/*methods