Biomedical subjects

Myung Jin Chung

Publications and source records attributed to Myung Jin Chung.

At least 19 recordsLinked to original sources

PubMed2006

Pulmonary fungal infection: imaging findings in immunocompetent and immunocompromised patients.

Histoplasmosis is the most common endemic mycosis in North America, and is followed by coccidioidomycosis and blastomycosis. Although the majority of these infections in immunocompetent persons are self-limited, some patients can develop severe pneumonitis or various forms of chronic pulmonary infection. Cryptococcoci, Aspergillus, Candidas, and Mucorals are ubiquitous organisms, which may affect immunocompromised patients. Specific imaging findings can be expected, depending on the organisms involved, underlying patients' conditions (immune status), and specific situations after immune depleting procedures.

Humans↗

PubMed2006

Drug-sensitive tuberculosis, multidrug-resistant tuberculosis, and nontuberculous mycobacterial pulmonary disease in nonAIDS adults: comparisons of thin-section CT findings.

The aim of this work was to compare thin-section CT (TSCT) findings of drug-sensitive (DS) tuberculosis (TB), multidrug-resistant (MDR) TB, and nontuberculous mycobacterial (NTM) pulmonary disease in nonAIDS adults. During 2003, 216 (113 DS TB, 35 MDR TB, and 68 NTM) patients with smear-positive sputum for acid-fast bacilli (AFB), and who were subsequently confirmed to have mycobacterial pulmonary disease, underwent thoracic TSCT. The frequency of lung lesion patterns on TSCT and patients' demographic data were compared. The commonest TSCT findings were tree-in-bud opacities and nodules. On a per-person basis, significant differences were found in the frequency of multiple cavities and bronchiectasis (P < 0.001, chi-square test and multiple logistic regression analysis). Multiple cavities were more frequent in MDR TB than in the other two groups and extensive bronchiectasis in NTM disease (multiple logistic regression analysis). Patients with MDR TB were younger than those with DS TB or NTM disease (P < 0.001, multiple logistic regression analysis). Previous tuberculosis treatment history was significantly more frequent in patients with MDR TB or NTM disease (P < 0.001, chi-square test and multiple logistic regression analysis). In patients with positive sputum AFB, multiple cavities, young age, and previous tuberculosis treatment history imply MDR TB, whereas extensive bronchiectasis, old age, and previous tuberculosis treatment history NTM disease.

Adult↗

PubMed2006

Thoracic actinomycosis: CT features with histopathologic correlation.

OBJECTIVE: Thoracic actinomycosis is a chronic suppurative pulmonary or endobronchial infection caused by Actinomyces israelii, a gram-positive anaerobic organism. We present the CT features of thoracic actinomycosis with histopathologic correlation. CONCLUSION: The typical CT feature of parenchymal actinomycosis is a chronic segmental air-space consolidation containing necrotic low-attenuation areas with frequent cavity formation. A broncholith can be secondarily infected with Actinomyces organisms, resulting in endobronchial actinomycosis. It usually manifests as a proximal endobronchial calcification associated with distal obstructive pneumonia.

Actinomycosis↗

PubMed2006

Do hemodynamic studies of stage T1 lung cancer enable the prediction of hilar or mediastinal nodal metastasis?

OBJECTIVE: We aimed to identify CT enhancement characteristics that predict hilar or mediastinal nodal metastasis in patients with stage T1 lung cancer. SUBJECTS AND METHODS: Eighty-four patients (50 men and 34 women; age range, 39-80 years; mean age, 61 years) with stage T1 lung cancer underwent a hemodynamic and a conventional morphologic CT study before curative surgical resection. Peak enhancement (maximum attenuation over the entire time course), net enhancement (peak enhancement minus preenhancement attenuation), maximum enhancement ratio (MER), time to peak enhancement, slope of enhancement on dynamic studies, nodule size, presence of tumor necrosis or thickening of bronchovascular bundles, and marginal characteristics on morphologic studies were analyzed and correlated with the presence of histologically determined mediastinal or hilar nodal metastasis. RESULTS: Mediastinal or hilar nodal metastases were found at surgery in 26 (31%) of 84 patients: mediastinal nodes in 13 (15%) and hilar nodes in 19 (23%). Six (7%) had both mediastinal and hilar nodal metastasis. Peak enhancement, net enhancement, and MER were significantly associated (p = 0.001, 0.002, and 0.008, respectively) with the presence of mediastinal or hilar nodal metastasis. A peak attenuation of 110 H or greater and a net enhancement of 60 H or greater predicted nodal metastasis with accuracies of 73% (61/84 nodules) and 73% (61/84 nodules) and odd ratios of 4.98 and 5.94, respectively. CONCLUSION: Stage T1 lung cancers showing peak enhancement of 110 H or greater or net enhancement of 60 H or greater on dynamic CT indicate a high likelihood of hilar or mediastinal nodal metastasis.

Adult↗

PubMed2006

Focal parenchymal lung lesions showing a potential of false-positive and false-negative interpretations on integrated PET/CT.

OBJECTIVE: We describe a number of benign focal lung lesions with increased 18F-FDG uptake that simulate lung cancer and malignant lesions that lead to false-negatives due to little 18F-FDG uptake on integrated PET/CT images. CONCLUSION: The integration of clinical history, morphologic findings of lung parenchymal lesions on the CT component, and metabolic activities on the PET component of integrated PET/CT can help reduce false interpretation of the study. A lung biopsy may be needed for lesions showing increased 18F-FDG uptake on PET for tissue confirmation irrespective of their morphology on CT.

Adult↗

PubMed2006

Bronchial and nonbronchial systemic arteries in patients with hemoptysis: depiction on MDCT angiography.

OBJECTIVE: In this pictorial essay, we show the usefulness of MDCT angiography for visualization of the bronchial and nonbronchial systemic feeder vessels responsible for hemoptysis. CONCLUSION: By providing thin-section transaxial, multiplanar reconstruction, and 3D images, CT angiography using MDCT allows comparable or better images than conventional angiography with respect to the depiction of bronchial or nonbronchial systemic arteries. CT angiography is particularly useful for visualizing the ectopic origin of bronchial arteries and nonbronchial systemic collateral arteries.

Adult↗

PubMed2006

Adenovirus pneumonia in adults: radiographic and high-resolution CT findings in five patients.

OBJECTIVE: The purpose of this study was to describe the radiographic and high-resolution CT (HRCT) findings of adenovirus pneumonia in five patients. CONCLUSION: Adenovirus pneumonia in adults appears as bilateral patchy parenchymal opacities on chest radiographs and as bilateral ground-glass opacities with a random distribution with or without consolidation on HRCT images. These findings, however, are not specific for adenovirus pneumonia.

Adenovirus Infections, Human↗

PubMed2006

Pulmonary sclerosing hemangioma presenting as solitary pulmonary nodule: dynamic CT findings and histopathologic comparisons.

OBJECTIVE: The purpose of this study was to describe the dynamic CT findings of pulmonary sclerosing hemangioma presenting as a solitary pulmonary nodule and to compare these findings with histopathologic findings. CONCLUSION: On dynamic CT, sclerosing hemangioma has strong and rapid enhancement attributed histopathologically to the presence of hemangiomatous or papillary components in the tumor.

Adult↗

PubMed2006

Tissue characterization of solitary pulmonary nodule: comparative study between helical dynamic CT and integrated PET/CT.

UNLABELLED: Recent advances in the technology of helical multidetector CT allow precise evaluations of nodule hemodynamics. In addition, the efficacy of tissue characterization has improved, and now sensitivity and specificity of >90% are achieved. Moreover, the efficacy of PET for the tissue characterization of solitary pulmonary nodules (SPNs) has also become of importance. The purpose of this study was to compare the diagnostic accuracy of helical dynamic (HD) CT (HDCT) and integrated PET/CT for pulmonary nodule characterization. METHODS: One hundred nineteen patients with an SPN underwent both HDCT (unenhanced scans, followed by series of images at 30, 60, 90, 120 s and at 5 and 15 min after intravenous injection of contrast medium) and integrated PET/CT. On HDCT, a nodule was regarded as malignant with a net enhancement of > or =25 Hounsfield units (HU) and a washout of 5-31 HU. On integrated PET/CT, nodules were considered malignant with a > or =3.5 maximum standardized uptake value and an 18F-FDG uptake greater than that of mediastinal structures. The sensitivity, specificity, and accuracy of the 2 modalities for malignancy were compared using the McNemar test. RESULTS: There were 79 malignant and 40 benign nodules. The sensitivity, specificity, and accuracy for malignancy on HDCT were 81% (64/79 nodules), 93% (37/40), and 85% (101/119), respectively, whereas those on integrated PET/CT were 96% (76/79), 88% (35/40), and 93% (111/119), respectively (P = 0.008, 0.727, and 0.011, respectively). All malignant nodules were interpreted correctly on either HDCT or PET/CT. CONCLUSION: Integrated PET/CT is more sensitive and accurate than HDCT for the malignant nodule characterization; therefore, PET/CT may be performed as the first-line evaluation tool for SPN characterization. Because HDCT has high specificity and acceptable sensitivity and accuracy, it may be a reasonable alternative for nodule characterization when PET/CT is unavailable.

Adult↗

PubMed2005

Prognostic factors and causes of death in Korean patients with idiopathic pulmonary fibrosis.

The purpose of this study was to investigate the prognostic factors at initial presentation and the causes of death in Korean patients with idiopathic pulmonary fibrosis (IPF), which might be different report wise, in comparison to the western countries. A retrospective review of 88 patients (mean 60.3 years, 69 male) was carried out and they were diagnosed as IPF positive. After diagnosis, the survival rate was 57% and 41% for third and fifth year, respectively (mean follow-up 39.1 months). Mortality was closely correlated with severe dyspnea at presentation (Hazard Ratio [HR], 2.6 per grade; p=0.015), lower initial forced vital capacity (HR, 1.7 per 10% predicted; p=0.004) and lower initial diffusing capacity of the lung (HR, 1.5 per 10% predicted; p=0.033). Treatment with specific drugs was ineffective against the survival when compared with symptomatic supportive care. Thirty-four patients (68%) died of worsened respiratory failure, seven (14%) died of infection and only one patient showed cardiovascular death. In conclusion, our study suggests that the severity of dyspnea and lung function tests at the time of diagnosis are the predictive factors for the survival of patients with IPF. In comparison to the reports from western countries, we observed that respiratory failure and pulmonary infection were more frequent causes of death, while cardiovascular death was rare in Korean patients with IPF.

Aged↗

PubMed2005

Non-small cell lung cancer: prospective comparison of integrated FDG PET/CT and CT alone for preoperative staging.

PURPOSE: To evaluate prospectively the accuracy of integrated positron emission tomography (PET) and computed tomography (CT) with use of fluorodeoxyglucose (FDG), compared with that of stand-alone CT, for the preoperative staging of non-small cell lung cancer, with surgical and histologic findings used as the reference standard. MATERIALS AND METHODS: Institutional review board approval and patient informed consent were obtained. From November 2003 to February 2004, 106 patients (78 men, 28 women; mean age, 56 years) with non-small cell lung cancer underwent curative surgical resection (tumor resection and lymph node dissection) after stand-alone CT followed by integrated FDG PET/CT. Tumor stages were determined by using the TNM and American Joint Committee on Cancer staging systems. Histopathologic results served as the reference standard. Statistically significant differences in tumor staging between integrated PET/CT and stand-alone CT were determined with P < .05 obtained by using the McNemar test or with a generalized estimating equation. RESULTS: The primary tumor was correctly staged in 84 patients (79%) at stand-alone CT and in 91 patients (86%) at integrated FDG PET/CT (P = .25). For the depiction of malignant nodes, the sensitivity, specificity, and accuracy of CT were 70% (23 of 33 nodal groups), 69% (248 of 360), and 69% (271 of 393), respectively, whereas those of PET/CT were 85% (28 of 33), 84% (302 of 360), and 84% (330 of 393) (P = .25, P < .001, and P < .001, respectively). There were 112 false-positive interpretations at CT for 54 hilar, 16 subcarinal, 29 paratracheal, 10 subaortic, and two pulmonary ligament nodal groups and one upper paratracheal group, compared with only 58 false-positive interpretations at PET/CT for 32 hilar, seven subcarinal, 13 lower paratracheal, and six subaortic nodal groups. There were 10 false-negative interpretations at CT for four hilar, two lower paratracheal, and two subcarinal nodal groups, one prevascular and retrotracheal group, and one inferior pulmonary group, but only five false-negative interpretations at PET/CT (one each for paratracheal, subaortic, subcarinal, inferior pulmonary, and hilar nodal groups). CONCLUSION: Integrated FDG PET/CT is significantly better than stand-alone CT for lung cancer staging and provides enhanced accuracy and specificity in nodal staging.

Carcinoma, Non-Small-Cell Lung↗

PubMed2005

Disseminated dendriform pulmonary ossification associated with usual interstitial pneumonia: incidence and thin-section CT-pathologic correlation.

The aim of this work was to assess the incidence of disseminated pulmonary dendriform ossification in usual interstitial pneumonia and nonspecific interstitial pneumonia, and to correlate thin-section computed tomography (CT) and histopathologic findings. We retrospectively reviewed thin-section CT and pathologic specimens of biopsy-proven usual interstitial pneumonia (75 patients, 57 men and 18 women, mean age 60 years, range 29-83 years) and nonspecific interstitial pneumonia (44 patients, 9 men and 35 women, mean age 55 years, range 20-73 years). On review of CT and histopathologic specimens, diffuse dendriform ossification was identified in five (four men and one woman, age range 41-68 years, mean 58 years) of 75 patients (6.7%) with usual interstitial pneumonia. It was not seen in any of 44 patients with nonspecific interstitial pneumonia. With thin-section CT (osteoporosis window; window width 818, level 273), disseminated dendriform pulmonary ossification was detected as multiple tiny calcifications in bibasilar subpleural lungs (100% sensitive and 100% specific when compared with histopathologic findings as the gold standard). The thin-section CT finding of multiple tiny calcifications in bibasilar subpleural lungs might be of some help in the differential diagnosis between usual interstitial pneumonia and nonspecific interstitial pneumonia, considering they were not seen in any patients with nonspecific interstitial pneumonia (0%, 0/44) in our series.

Biopsy↗

PubMed2005

Metabolic lung disease: imaging and histopathologic findings.

Metabolic lung disease includes pulmonary alveolar proteinosis (PAP), pulmonary amyloidosis, metastatic pulmonary calcification, dendritic pulmonary ossification, pulmonary alveolar microlithiasis, and storage diseases. In pulmonary alveolar proteinosis, CT demonstrates air-space consolidation with thickened interlobular septa, producing the so-called "crazy paving" appearance. Pulmonary amyloidosis can appear as parenchymal nodules (nodular parenchymal form), diffuse interstitial deposit (diffuse interstitial form), or submucosal deposits in the airways (tracheobronchial form). Metastatic pulmonary calcification may appear on high-resolution CT as numerous 3- to 10-mm diameter calcified nodules or, more commonly as fluffy and poorly defined nodular opacities. In pulmonary microlithiasis, high-resolution CT demonstrates diffuse punctuate micronodules showing slight perilobular predominance resulting in apparent calcification of interlobular septa. Niemann-Pick disease appears as ground-glass attenuation in the upper lung zone and thickening of the interlobular septa in the lower lung zone. Radiologic study including high-resolution CT will be helpful for the diagnosis and follow-up of these diseases.

Adult↗

PubMed2005

Solitary pulmonary nodule: characterization with combined wash-in and washout features at dynamic multi-detector row CT.

PURPOSE: To prospectively assess the accuracy of combined wash-in and washout characteristics at dynamic contrast material-enhanced multi-detector row computed tomography (CT) in distinguishing benign from malignant solitary pulmonary nodules. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. The study included 107 patients (62 men, 45 women; mean age, 55 years; range, 22-81 years) with a solitary pulmonary nodule. After unenhanced CT (2.5-mm collimation) scans were obtained, dynamic CT was performed by using a helical technique (series of images obtained throughout the nodule, with 2.5-mm collimation, at 30, 60, 90, and 120 seconds and 4, 5, 9, 12, and 15 minutes) after intravenous injection of contrast medium (120 mL). Tissue diagnosis was made in 70 nodules, and follow-up images showed benignancy in the remaining 37 (no change in size, n = 32; decrease in size, n = 5). CT findings were analyzed in terms of wash-in and washout of contrast medium. Sensitivity, specificity, and accuracy for malignant nodules were calculated by considering both the wash-in and washout characteristics at dynamic CT. RESULTS: There were 49 malignant and 58 benign nodules. When diagnostic criteria for malignancy of both wash-in of 25 HU or greater and washout of 5-31 HU were applied, sensitivity, specificity, and accuracy for malignancy were 94% (46 of 49 nodules), 90% (52 of 58 nodules), and 92% (98 of 107 nodules), respectively. Of 58 benign nodules, 27 showed less than 25 HU wash-in, 14 showed persistent contrast enhancement without washout and with wash-in of 25 HU or greater, and 11 showed washout greater than 31 HU and wash-in of 25 HU or greater. CONCLUSION: Evaluation of solitary pulmonary nodules by analyzing combined wash-in and washout characteristics at dynamic contrast-enhanced multi-detector row CT showed 92% accuracy for distinguishing benign nodules from malignant nodules.

Adult↗

PubMed2005

Giant cell interstitial pneumonia: high-resolution CT and pathologic findings in four adult patients.

OBJECTIVE: The purpose of our study was to describe the high-resolution CT and pathologic findings of giant cell interstitial pneumonia (GIP) in four adult patients. CONCLUSION: GIP appears on high-resolution CT as ground-glass and irregular linear opacities in both lungs. These CT findings correspond histopathologically to areas of interstitial thickening caused by fibrosis and inflammatory cell infiltration and to areas of intraalveolar accumulation of macrophages and multinucleated giant cells.

Adult↗

PubMed2005

High-resolution sonography of the rib: can fracture and metastasis be differentiated?

OBJECTIVE: Our aim was to evaluate whether high-resolution sonography can provide additional information concerning rib lesions compared with radiography or bone scintigraphy. MATERIALS AND METHODS: Fifty-eight patients with high-uptake rib lesions seen on bone scintigraphy were selected. Radiography and rib high-resolution sonography were performed on these patients. High-resolution sonography was performed using a linear 5-12 MHz transducer. By means of clinical history, histopathologic examination, and follow-up observation, these patients were classified into rib fracture (n = 37), rib metastasis (n = 18), or unknown (n = 3) groups. High-resolution sonography images of the 55 proven cases were reviewed for the presence of five representative findings: cortical disruption, callus formation, cortical deformity, mass, or bone destruction. The frequencies of these findings were compared between the groups with fracture and metastasis. RESULTS: Rib lesions were matched by bone scintigraphy and high-resolution sonography in 53 (96%) of 55 patients and by bone scintigraphy and plain radiography in 23 (42%) of 55 patients. High-resolution sonography revealed 17 (94%) of 18 patients with metastasis and 36 (97%) of 37 patients with rib fractures. Metastatic lesions were seen as mass formation (n = 13) and irregular bone destruction (n = 7) on high-resolution sonography. Fracture was seen as cortical disruption with or without hematoma (n = 17), callus formation (n = 9), or cortical deformity, such as angling or stepping (n = 12). CONCLUSION: High-resolution sonography of the ribs is a useful method of characterizing rib lesions in patients who have hot-uptake lesions on bone scintigraphy.

Adult↗

PubMed2005

Hypothesis on the evolution of cavitary lesions in nontuberculous mycobacterial pulmonary infection: thin-section CT and histopathologic correlation.

OBJECTIVE: The objectives of our study were to evaluate the thin-section CT findings of the cavitary form of nontuberculous mycobacterial pulmonary infection and correlate these imaging findings with the histopathologic findings concerning the development of bronchiectasis and of centrilobular nodules and cavitary lesions. MATERIALS AND METHODS: We retrospectively reviewed thin-section CT scans (2.5-mm collimation, both axial and coronal reformation images) of 24 cases (male-female ratio, 13:11; mean age, 61 years; age range, 43-82 years) of the cavitary form of culture-proven Mycobacterium avium-intracellulare complex pulmonary infection including two cases with lobectomy specimens. Any changes in CT findings detected on the follow-up CT scans that were available for seven patients (follow-up interval, 6-24 months; mean, 12 months) were also assessed. RESULTS: Thin-section CT findings were bronchiectasis (24/24 patients, 100%), a patent bronchus running into a cavitary lesion (the "feeding bronchus" appearance) (18/24, 75%), nodules less than 10 mm (17/24, 71%), centrilobular nodules (17/24, 71%), nodules of 10-30 mm (13/24, 54%), peribronchial nodules (8/24, 33%), lobular consolidation (6/24, 25%), bronchial wall thickening (4/24, 17%), and consolidation (2/24, 8%). Two lobectomy specimens showed large cavitary consolidations with the feeding bronchus appearance on pathologic specimens. In two patients, small peribronchial nodules had changed into cavitary nodules with the feeding bronchus appearance on follow-up CT, which represented inflamed focal cystic bronchiectasis. CONCLUSION: In the cavitary form of M. avium-intracellulare complex pulmonary infection, the feeding bronchus appearance is another very frequent thin-section CT finding. This appearance may suggest that peribronchial nodules of M. avium-intracellulare complex infection evolve into inflamed focal cystic bronchiectasis manifesting as cavitary lesions.

Adult↗

PubMed2005

CT findings of surgically resected pleomorphic carcinoma of the lung in 30 patients.

OBJECTIVE: The objective of our study was to assess the CT features of surgically resected pleomorphic carcinoma of the lung. CONCLUSION: The CT features of pleomorphic carcinoma of the lung appear to be dictated by the epithelial component of the tumor. Among the various subtypes of pleomorphic carcinoma, the large cell and giant cell subtype showed constant CT features including subpleural location, peritumoral areas of ground-glass attenuation, and extensive central low-attenuation areas.

Carcinoma, Non-Small-Cell Lung↗