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Jung-Gi Im

Publications and source records attributed to Jung-Gi Im.

At least 37 records · Page 2Linked to original sources
PubMed2003

Recurrent bronchobiliary fistula: unsuccessful management with repeated insertion of metallic biliary stent.

This case of a recurrent bronchobiliary fistula was first managed temporarily with repeated metallic biliary stent placement, and finally required surgery. A 65-year-old man, who had undergone a hepatic resection for metastatic colon carcinoma, with a bronchobiliary fistula was treated with metallic biliary stent placement for a stenosis in the common bile duct. During 16 months of follow-up, the biliptysis recurred twice by a recurrent stricture of the common bile duct, which was managed by placement of a second and third stent in a coaxial manner. Three months after placement of the third stent, jaundice developed and the patient finally underwent a Roux-en-Y choledochojejunostomy.

Aged↗
PubMed2002

CT of tuberculosis and nontuberculous mycobacterial infections.

Radiologic manifestations of pulmonary tuberculosis (TB) can vary according to several host factors, including prior exposure to TB, age, and underlying immune status. Although chest radiography is the mainstay in the evaluation of pulmonary TB, CT generally is required to detect fine lesions overlooked on chest radiographs, to define equivocal lesions, or to evaluate complications. High-resolution CT is useful in understanding the pathologic process of the disease and in determining disease activity in selected cases. This article describes the characteristic CT findings of various forms of pulmonary TB and nontuberculous mycobacterial infection according to immune status of the patients, and assesses the role of CT in the diagnosis and management of pulmonary TB.

AIDS-Related Opportunistic Infections↗
PubMed2002

Identification of angiogenesis in primary breast carcinoma according to the image analysis.

Tumor angiogenesis may be an independent prognostic factor for breast cancer survival. However, we can get the angiogenic property of the breast cancer only after the removal of breast tissue. To get this information before surgical resection of the tumor, we evaluated 29 breast carcinoma patients with Tc-99m MIBI scintimammography and power Doppler ultrasound (US) with a microbubble contrast agent preoperatively and compare their results with intratumoral microvessel density (IMD) and reverse transcriptase-polymerase chain reaction (RT-PCR) of VEGF mRNA. IMD was well correlated with VEGF121 (r = 0.220, P = 0.024) and VEGF165 (r = 0.419, P = 0.046) mRNA level of the tumor. Power Doppler US grading of the tumor is well correlated with IMD (r = 0.552, P = 0.033). However, early uptake and washout index calculated from Tc-99m MIBI scintimammography showed no correlation with IMD or VEGF mRNA level, while washout index was inversely correlated with power Doppler US grading (r = -0.945, P = 0.001). In conclusion, the preoperative evaluation of breast cancer with power Doppler US with a microbubble contrast agent could predict tumor angiogenesis. Tc-99m MIBI scintimammography needs further study to use it as an image analysis for angiogenesis.

Adult↗
PubMed2002

Tuberculosis in patients with myelodysplastic syndromes.

AIM: The purpose of our study was to describe radiological manifestations of tuberculosis in patients with myelodysplastic syndromes. MATERIALS AND METHODS: Chest radiographs and CTs of 12 patients with tuberculosis among 195 consecutive patients with myelodysplastic syndrome, proved by bone marrow biopsy, were reviewed. Six of the 12 patients presented with tuberculosis and were subsequently found to have myelodysplastic syndrome. RESULTS: Chest radiographs and CTs revealed pulmonary tuberculosis in all 12 patients and extrapulmonary tuberculous involvement in six (50%). Initial chest radiographic findings of pulmonary tuberculosis included a primary pattern (n = 6), a post-primary pattern (n = 3), a miliary pattern (n = 1), atypical infiltrates (n = 1) and normal radiograph (n = 1). Tuberculosis involved extrathoracic lymph nodes (n = 5), liver (n = 2), spleen (n = 2), kidney (n = 2), bowel (n = 2), pericardium (n = 2) peritoneum (n = 1) and rib (n = 1). CONCLUSION: Tuberculosis is a relatively common cause of infection in patients with myelodysplastic syndromes. The radiological appearance of pulmonary tuberculosis in myelodysplastic syndromes is often a primary pattern, and there is frequently extrapulmonary involvement.

Adult↗
PubMed2002

Systemic arterial supply to the normal basal segments of the left lower lobe: radiographic and CT findings in 11 patients.

SUMMARY: To assess the radiologic findings of systemic arterial supply to the normal basal segments of the left lower lobe, chest radiographs and CT scans of all 11 patients were reviewed retrospectively by two chest radiologists. On posteroanterior chest radiographs (n = 11), the anomalous systemic artery arising from the descending thoracic aorta was shown as a retrocardiac mass (n = 11). Absence of normal lower lobar pulmonary artery shadow (n = 11), partial obliteration of the descending aortic interface (n = 9), and increased interstitial markings in left lower lung zone (n = 8) were also noted. On contrast-enhanced scans (n = 11), abrupt tapering of the normal left lower lobar pulmonary artery distal to the origin of superior segmental artery (n = 11), aberrant systemic artery originating from the descending aorta (n = 11), mild volume loss in the left lower lobe (n = 11), diffuse dilatation of the intrapulmonary peripheral vasculature (n = 11) and areas of ground-glass opacity (n = 10) in the basal segments of the left lower lobe were seen. Because chest radiography and CT consistently demonstrate several combinations of characteristic findings, conventional aortography may not be necessary for proper diagnosis of this anomaly.

Adult↗
PubMed2002

Detection of pulmonary edema in pigs: storage phosphor versus amorphous selenium-based flat-panel-detector radiography.

PURPOSE: To compare diagnostic accuracy of soft-copy selenium-based digital radiographic images and soft-copy computed radiographic images obtained for detection of pulmonary edema in pigs. MATERIALS AND METHODS: Oleic acid was injected intraatrially into three pigs (weight, 20-25 kg) at doses of 0.04, 0.05, and 0.06 mL/kg to induce pulmonary edema. Thirty-seven sets of computed radiographic, digital radiographic, and thin-section computed tomographic (CT) scans were obtained every 20-30 minutes in three pigs over 4-6 hours. Images were masked for identity, randomly sorted, and displayed on a monitor. Four radiologists rated each image for presence of parenchymal opacities by using a dichotomous scoring system in two sessions. Presence of pulmonary edema was determined with thin-section CT and a severity scale. Intra- and interobserver variations were determined with the kappa statistic and the Z test and with the Cochran Q test and the McNemar test, respectively. True-positive, true-negative, false-positive, and false-negative rates were determined. McNemar test was used to determine statistical significance of differences in detection between computed and digital radiographic images. RESULTS: There was no significant intra- or interobserver variation, except for one pair of observers during the first interpretative session with computed radiographic images (P =.016, McNemar test). Overall sensitivity (92.1%) and diagnostic accuracy (90.2%) of digital radiography were significantly higher than those of computed radiography (79.6% and 83.4%, respectively) (P <.001 for sensitivity, P =.01 for diagnostic accuracy, McNemar test). In detection of minimal and mild pulmonary edema, sensitivity of digital radiography (84%) was significantly higher than that of computed radiography (58%) (P <.001). CONCLUSION: Soft-copy digital radiographic images are superior to soft-copy computed radiographic images obtained for detection of mild pulmonary edema in pigs.

Animals↗
PubMed2002

Detection of simulated chest lesions by using soft-copy reading: comparison of an amorphous silicon flat-panel-detector system and a storage-phosphor system.

PURPOSE: To compare observer performance by using soft-copy images produced by an amorphous silicon flat-panel-detector system and a storage-phosphor system for the detection of simulated chest lesions. MATERIALS AND METHODS: To test the diagnostic performance of these two systems, four types of simulated lesions (nodules, micronodules, lines, and reticular opacities) were superimposed over an anthropomorphic chest phantom. Digital chest radiographs were acquired with amorphous silicon flat-panel-detector (3-K [K = 1,000] matrix, 12 bits) and storage-phosphor radiography (4-K matrix, 10 bits). Six board-certified radiologists evaluated soft-copy images on a high-resolution video monitor (2,048 x 2,560 x 8 bits). A total of 14,400 observations were analyzed in terms of receiver operating characteristics. RESULTS: Average performance in terms of nodule detection was significantly better (P <.05) with the flat-panel-detector system than with the storage-phosphor system. For micronodules, lines, and reticular opacities, no significant detection differences in averaged performance were found between the two detector systems. CONCLUSION: In the evaluation of soft-copy images, the amorphous silicon detector system appears to be superior to the storage-phosphor system for the detection of pulmonary nodules.

Lung Diseases↗
PubMed2002

Multifocal, multicentric, and contralateral breast cancers: bilateral whole-breast US in the preoperative evaluation of patients.

PURPOSE: To evaluate the efficacy of preoperative bilateral whole-breast ultrasonography (US) in the detection of additional multifocal, multicentric, and contralateral cancers and the effect of US information on therapeutic decisions. MATERIALS AND METHODS: Two hundred one patients who had newly diagnosed breast cancer or who were suspected of having breast cancer underwent US examination of the ipsilateral and contralateral breasts with a 10-, 12-, or 13-MHz transducer. All solid lesions found at US alone were classified according to level of suspicion and were selected for biopsy. The US results were compared with mammographic findings. Sensitivity, specificity, and positive and negative predictive values were calculated. RESULTS: In ipsilateral breasts, US depicted 194 (97%) of 201 foci of invasive cancer and 52 (75%) of 69 foci of ductal carcinoma in situ (DCIS), whereas mammography and physical examination depicted 173 (86%) foci of invasive cancer and 56 (81%) foci of DCIS. In the contralateral breast, US depicted 11 (92%) of 12 foci of invasive cancer and four (57%) of seven foci of DCIS, whereas mammography and physical examination depicted six (50%) foci of invasive cancer and five (71%) foci of DCIS. Overall, US depicted mammographically and clinically unsuspected multifocal or multicentric cancers in 28 patients (14%) and contralateral cancer in eight patients (4%). On the basis of these US findings, therapy was correctly changed in 32 patients (16%). The sensitivity, specificity, and positive and negative predictive values of prospective classification of 77 solid lesions detected at US alone were 100% (36 of 36), 51% (21 of 41), 64% (36 of 56), and 100% (21 of 21), respectively. CONCLUSION: Bilateral whole-breast US complements mammography in the preoperative evaluation of patients with breast cancer.

Adult↗
PubMedDate not supplied

Pulmonary blastoma: radiologic findings in five patients.

PURPOSE: To determine the radiologic findings of pulmonary blastoma on chest radiograph and CT. MATERIALS AND METHODS: Chest radiographs and CT scans of five patients with pathologically proven pulmonary blastoma were retrospectively evaluated and radiologic findings were correlated with histopathologic findings. RESULTS: On chest radiograph, the pulmonary blastoma manifested as a solitary parenchymal mass (n = 2), a solitary parenchymal nodule (n = 1), hilar bulging with fingerlike parenchymal opacities (n = 1), or opacification of hemithorax (n = 1). On CT, the pulmonary blastoma manifested as a solitary parenchymal mass (n = 2), a solitary parenchymal nodule (n = 1), an endobronchial mass with postobstructive pneumonitis (n = 1), or a parenchymal mass with multiple subpleural masses and pleural effusion (n = 1). CONCLUSION: Pulmonary blastomas most commonly manifested as a solitary parenchymal mass on chest radiograph and CT. These radiologic features are nonspecific and many primary or metastatic tumors of the lung could be included in differential diagnosis.

Adult↗
PubMedDate not supplied

Posterior subpleural nodules in patients with underlying malignancies: value of prone computed tomography.

PURPOSE: The aim of this study was to investigate the value of prone computed tomography (CT) in patients with underlying malignancies and posterior subpleural nodule(s) on a supine CT scan. METHOD: A prospective study was performed on 26 patients who had an underlying malignancy and posterior subpleural nodule(s) on a chest CT scan. Helical CT scanning with a 3-mm collimation was done in both the supine and prone positions at an interval of 1-50 days (mean, 9 days). The size, shape, and location of the nodule(s) as well as the associated dependent ground-glass opacity on an initial CT scan and the change in the nodule(s) on follow-up supine and prone CT scans were analyzed. RESULTS: The nodules were single in 10 patients and multiple in 16. In 25 of 26 patients, the nodules were located in the lower lobes. Most had an oval shape, forming an obtuse angle with the adjacent pleura. The size ranged from 5 mm x 2 mm to 12 mm x 4 mm (mean, 7 mm x 3 mm). An associated dependent ground-glass opacity was found in 11 patients. At the follow-up examinations, the posterior subpleural nodules had disappeared in 10 patients on the supine scan and in 21 patients on the prone scan. The persistent nodules on the prone CT scan were granulomas in 2 patients and metastases in 3 patients. CONCLUSION: Posterior subpleural nodules may be reversible, and the nodular atelectasis can be differentiated from true nodules without using invasive procedures by employing prone CT scanning.

Adult↗
PubMedDate not supplied

Cystic tumors in the anterior mediastinum. Radiologic-pathological correlation.

Anterior mediastinal neoplasms comprise a diverse group of tumors and occasionally manifest as a cystic lesion. We retrospectively reviewed computed tomography (CT) scans in 46 patients with pathologically proved cystic anterior mediastinal tumors. We categorize them into a pure cystic mass and a cystic tumor with a solid portion. In this pictorial essay, the radiologic appearances of cystic anterior mediastinal tumors are described with CT and illustrated with their gross and histopathological findings on resected specimen.

Bronchi↗
PubMedDate not supplied

Multidrug-resistant tuberculosis versus drug-sensitive tuberculosis in human immunodeficiency virus-negative patients: computed tomography features.

OBJECTIVES: To compare the computed tomography (CT) features of patients with multidrug-resistant tuberculosis with those of patients with drug-sensitive tuberculosis in a country not associated with the human immunodeficiency virus (HIV) epidemic. METHODS: The CT images of 47 patients with multidrug-resistant tuberculosis were compared with those of 47 patients with drug-sensitive tuberculosis as a control group. Each multidrug-resistant tuberculosis patient was age (decade) and gender matched to a drug-sensitive tuberculosis patient. All patients were seronegative to HIV. This study evaluated the presence of centrilobular nodules, consolidation, emphysema, bronchiectasis, lung destruction, calcified granuloma, cavitation, pleural effusion, and lymphadenopathy. A statistical comparison was performed by using the Fisher exact test for univariate analysis and a multiple logistic regression method for multivariate analysis. RESULTS: In univariate analysis, bronchiectasis, lung destruction, a calcified granuloma, and cavitation were more frequently observed in multidrug-resistant tuberculosis than in drug-sensitive tuberculosis. Multivariate analysis showed that cavity formation was the only significant difference between multidrug-resistant tuberculosis and drug-sensitive tuberculosis. In patients with cavitary tuberculosis, multiple cavities (>3 cavities) were observed only in patients with multidrug-resistant tuberculosis. CONCLUSIONS: Most patients with multidrug-resistant tuberculosis had cavity formation on CT. Although the presence of a cavity does not mean multidrug resistance, multiple cavities suggest the possibility of multidrug-resistant tuberculosis.

Adolescent↗
PubMedDate not supplied

The value of computed tomography for predicting empyema-associated malignancy.

OBJECTIVE: To determine the value of computed tomography (CT) scanning in detecting associated malignancy in patients with chronic empyema. METHODS: Two radiologists retrospectively reviewed CT scans of 112 consecutive patients with chronic empyema and arrived at a consensus about the findings. Among these patients, 6 were confirmed by pathology evaluation to have empyema-associated malignancy (EAM), including 4 lymphomas. The CT scans were evaluated for the presence of the following findings: a mass in the empyema sac; mass involvement of the extrapleural fat, chest wall, rib, and lung; bulging of the empyema sac; nodular pleural thickening; empyema involvement of the mediastinal pleura; presence of lung nodules (>1 cm); and mediastinal lymph node enlargement. The association between the CT findings and the EAM was analyzed with the Fisher exact test. A multiple logistic regression analysis was used to determine the predictive variables for EAM. Sensitivity, specificity, and positive predictive value were calculated for each finding. RESULTS: All CT findings, except rib involvement and bulging of empyema sac, were significantly associated with EAM (P<0.05). The finding of the presence of a mass, extrapleural fat, and mediastinal involvement showed relatively high sensitivity (100%, 67%, 67%, respectively) and specificity (81%, 87%, 91%, respectively). A bulging of the empyema sac and nodular pleural thickening showed 100% sensitivity, but low specificity (39% and 44%, respectively). Findings from the multiple logistic regression analysis revealed that the presence of a mass and empyema of the mediastinal pleura were significant variables associated with EAM (P<0.05). CONCLUSIONS: Although many CT findings are associated with EAM, most showed either low positive predictive value or low sensitivity. A variety of CT findings should be considered when evaluating CT image-based detection of EAM.

Adolescent↗
PubMedDate not supplied

US of ductal carcinoma in situ.

Little is known about the ultrasonographic (US) features of ductal carcinoma in situ (DCIS) of the breast because this entity usually manifests as pure mammographic calcifications and is rarely evaluated with US. US findings were recorded in 70 patients with DCIS and then analyzed and correlated with mammographic and histologic findings. A microlobulated mass with mild hypoechogenicity, ductal extension, and normal acoustic transmission was the most common US finding in DCIS. Spiculated margins, marked hypoechogenicity, a thick echogenic rim, and posterior acoustic shadowing at US often suggested the presence of invasion. US performed with a 10-13-MHz transducer and optimal technique can be used as a complement to mammography in detecting and evaluating DCIS of the breast, as it demonstrates breast lesions associated with malignant microcalcifications in most cases. The main benefit of identifying a US abnormality in women with mammographically detected DCIS is to allow the use of US to guide interventional procedures (eg, needle biopsy, needle localization). US may also be helpful in detecting DCIS without calcifications and in evaluating disease extent in women with dense breasts. Nevertheless, further research is needed to delineate the role of US in the evaluation of patients with DCIS.

Adult↗
PubMedDate not supplied

Peripheral T-cell lymphoma: spectrum of imaging findings with clinical and pathologic features.

Most radiologists are unfamiliar with peripheral T-cell lymphoma (PTCL) because PTCL represents a relatively small proportion of lymphomas and has a lower prevalence in Western countries. The World Health Organization classification of lymphoid neoplasms announced in 1999 resolved criticisms about lymphoma classification and aroused new interest in PTCL. The specific clinicopathologic entities of PTCL have particular primary locations and particular clinical and pathologic features. Radiologic images of patients with pathologically proved PTCL were retrospectively reviewed; clinical and pathologic data were also reviewed. PTCL involves various organs including the sinonasal cavity, airway, intestinal tract, skin, lymph nodes, liver, lung, and musculoskeletal system. The pattern of disease involvement in PTCL is not random. There is a correlation between specific clinicopathologic entities and the primary site of involvement, although the findings in the disseminated stage of disease do not allow differential diagnosis. It is significant that the radiologic features or locations of several entities are different from those of lymphoma with the B-cell phenotype. Radiologic demonstration of disease progression beyond the primary site is clinically important because systemic dissemination in most of the entities leads to a dramatic change in the prognosis.

Adult↗
PubMedDate not supplied

Automated lung nodule detection at low-dose CT: preliminary experience.

OBJECTIVE: To determine the usefulness of a computer-aided diagnosis (CAD) system for the automated detection of lung nodules at low-dose CT. MATERIALS AND METHODS: A CAD system developed for detecting lung nodules was used to process the data provided by 50 consecutive low-dose CT scans. The results of an initial report, a second look review by two chest radiologists, and those obtained by the CAD system were compared, and by reviewing all of these, a gold standard was established. RESULTS: By applying the gold standard, a total of 52 nodules were identified (26 with a diameter < or = 5 mm; 26 with a diameter >5 mm). Compared to an initial report, four additional nodules were detected by the CAD system. Three of these, identified only at CAD, formed part of the data used to derive the gold standard. For the detection of nodules >5 mm in diameter, sensitivity was 77% for the initial report, 88% for the second look review, and 65% for the CAD system. There were 8.0+/-5.2 false-positive CAD results per CT study. CONCLUSION: These preliminary results indicate that a CAD system may improve the detection of pulmonary nodules at low-dose CT.

Adult↗
PubMedDate not supplied

False positive and false negative FDG-PET scans in various thoracic diseases.

Fluorodeoxyglucose (FDG)-positron emission tomography (PET) is being used more and more to differentiate benign from malignant focal lesions and it has been shown to be more efficacious than conventional chest computed tomography (CT). However, FDG is not a cancer-specific agent, and false positive findings in benign diseases have been reported. Infectious diseases (mycobacterial, fungal, bacterial infection), sarcoidosis, radiation pneumonitis and post-operative surgical conditions have shown intense uptake on PET scan. On the other hand, tumors with low glycolytic activity such as adenomas, bronchioloalveolar carcinomas, carcinoid tumors, low grade lymphomas and small sized tumors have revealed false negative findings on PET scan. Furthermore, in diseases located near the physiologic uptake sites (heart, bladder, kidney, and liver), FDG-PET should be complemented with other imaging modalities to confirm results and to minimize false negative findings. Familiarity with these false positive and negative findings will help radiologists interpret PET scans more accurately and also will help to determine the significance of the findings. In this review, we illustrate false positive and negative findings of PET scan in a variety of diseases.

Cryptococcosis↗