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

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 ; Diagnosis ; Humans ; Lung ; Lung, Hyperlucent* ; Radiography ; Radiography, Thoracic ; Retrospective Studies ; Thorax ; Tomography, X-Ray Computed

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 ; Carcinoma, Bronchogenic* ; Dilatation ; Humans ; Korea ; Mucus ; Pneumonia* ; Prognosis ; Pulmonary Atelectasis* ; Radiography, Thoracic ; Tuberculosis*

A variety of disease states are marked by prolonged and profound eosinophilia associated with localized or widespread eosinophilic infiltrates. Cardiac involvement maybe a major cause of morbidity and mortality of this disease. We report a case of acute peri-myocarditis with eosinophilia, which was confirmed as eosinophilic myocardilic myocarditis by endomyocardial biopsy.
Biopsy ; Eosinophilia ; Eosinophils* ; Mortality ; Myocarditis*

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

BACKGROUND AND OBJECTIVES: A rotation chair test has been used to evaluate the function of the horizontal semicircular canals. Currently, two chair systems according to the presence of cylindrical darkroom are used in a clinic setting. However, it has not been thoroughly investigated whether one system is superior to the other system or not. In this study, we aimed to compare test outcomes and subject convenience between two systems. SUBJECTS AND METHODS: Twenty subjects with no history of otologic disease were enrolled. Subjects were tested with two systems: system [A] with a cylindrical chamber and system [B] with no chamber. The results of sinusoidal harmonic acceleration (SHA), step velocity (SV), and visual fixation (VFX) tests were compared between the systems. Subject convenience was assessed with a questionnaire survey and results were compared between the systems. RESULTS: There were no significant differences in gain or asymmetry in SHA test between the systems. However, the phase of system [A] was significantly lower than that of system [B] at 0.16 Hz. There was no significant difference between the systems in directional preponderance (DP) gain or DP time constant. Regarding the VFX test, gain was higher in system [A] than system [B]. Subjects reported less stuffiness and less anxiety with system [B] than system [A], while preferring the system [A] goggles. CONCLUSIONS: A rotation chair system without a darkroom can provide a more comfortable experience for subjects in terms of stuffiness and anxiety, while showing comparable results in SHA and SV tests with a darkroom system.
Acceleration ; Anxiety ; Ear Diseases ; Eye Protective Devices ; Semicircular Canals

PURPOSE: The TNM classification for carcinoma of the colon and the rectum provides more detail than other staging systems. This study was performed to evaluate the effectiveness of AJCC staging system (5th ed., 1997) for the colorectal cancer in predicting prognosis. METHODS: We analyzed a data base of 1,233 colorectal cancer patients (M:F=673:560) who underwent surgery in Asan Medical Center during July 1989-December 1996. Survival analysis was performed between the stages and the subgroups in same stage by using Kaplan-Meier method and log rank test. Borderline subgroup comparison between the stages was performed, also. Significance was assigned to a P value of <0.05. RESULTS: Mean age of the patients was 57 (19-90) years old. Median follow-up period was 42 (6-129) months. The number of patients in each stage were 0: 15, I: 152, II: 390, III: 465, IV: 199. The 5 year overall & disease free survival rates of each stage were 100%, 100% (in stage 0), 96.4%, 93.6% (in stage I), 82.7%, 82.2% (in stage II), 59.9%, 55.3% (in stage III), and 7.3%, 24.9% (in stage IV), respectively (P=0.000). Subgroup analysis in stage I (T1N0 vs. T2N0) and II (T3N0 vs. T4N0) revealed no differences. However, in stage III, N1 (n=246) group showed better survival than N2 (n=219) group (70.3%, 65.5% vs. 49.2%, 44.6%: P=0.000). Borderline survival analysis between stage I and II (T2N0 vs. T3N0) was significantly different (96.6%, 95.7% vs 82.7%, 82.3%: P=0.006). However, between stage II and III (T4N0 vs. T1N1), appropriate analysis was impossible due to small number of cases. CONCLUSIONS: AJCC staging system for colorectal cancer was reliable and effective in predicting prognosis. However, substages are needed in stage III.
Chungcheongnam-do ; Classification ; Colon ; Colorectal Neoplasms* ; Disease-Free Survival ; Follow-Up Studies ; Humans ; Prognosis ; Rectum

No abstract available in English.
Adenocarcinoma, Bronchiolo-Alveolar* ; Pathology*

PURPOSE: The purpose of this study was to evaluate the high-resolution CT(HRCT) appearance of abnormalities of small airways and lung parenchyma associated with bronchiectasis and to correlate HRCT appearance and the results of pulmonary function tests. MATERIALS AND METHODS: The author retrospectively reviewed medical recordsand HRCT scans of 33 patients with bronchiectasis. Abnormalities of small airways and lung parenchyma in lobeswith bronchiectasis were assessed on HRCT scan. The findings on HRCT were correlated with the results of pulmonary function tests in 20 patients. In two specimens obtained at lobectomy, histologic examinations were conducted to determine the pathologic basis for CT findings of disease of small airways. RESULTS: Patchy areas of low attenuation(n=27), centrilobular nodules or branching opacities(n=20), irregular hyper attenuation(n=16), and areasof ground-glass attenuation(n=4) were observed on HRCT scans. In the lobar evaluation, areas of low attenuation were observed in 66(76%) of the 87 lobes with bronchiectasis. Areas of low attenuation were also identified inseven(9%) of the 75 lobes without bronchiectasis. On expiratory HRCT, the lung parenchyma with areas of low attenuation did not show a normal increase in CT attenuation and remained more lucent than surrounding normallung, which suggested that air was trapped in the lung parenchyma. Of the 20 patients who underwent pulmonary function tests, six showed an obstructive pattern. These six had more lobes with bronchiectasis and with areas oflow attenuation than the other 14 patients, who did not have an obstructive pulmonary function pattern(p<.01). Intwo patients who had undergone lobectomy, pathologic examination showed bronchiolities obliterans in small airway speripheral to the dilated bronchi. CONCLUSION: In bronchiectasis, areas of low attenuation and centrilobular nodules or branching opacities are commonly observed in the lung parenchyma peripheral to the dilated bronchi on HRCT. These HRCT findings correspond pathologically to bronchiolitis obliterans and to lung parenchyma with trapped air. The number of loves with bronchiectasis and with areas of low attenuation correlate significantly with an obstructive pattern on pulmonary function tests.
Bronchi ; Bronchiectasis* ; Bronchiolitis ; Bronchiolitis Obliterans ; Humans ; Love ; Lung ; Respiratory Function Tests* ; Retrospective Studies

A wide variety of pulmonary disorders related to hemodialysis or pre-existing renal disease occurs in hemodialysis patients. The disorders may be classified as 1) pulmonary abnormalities associated with chronic renal failures; 2) pulmonary complications arising during hemodialysis; 3) pulmonary infection; or 4) pulmonary-renal syndrome. An awareness of the various possible pulmonary disorders arising in hemodialysis patients may be helpful for the proper and timely management of such patients. We describe and illustrate various radiographic and CT findings of variable pulmonary disorders in hemodialysis patients.
Humans ; Renal Dialysis* ; Renal Insufficiency ; Vasculitis