Objective To describe the CT manifestations of thymic epithelial tumor and explore the correlation between CT findings and post-operative tumor-related survival time. Methods Ninety-one patients who underwent CT scan before operation were reviewed retrospectively. All cases had operation and were classified according to the WHO classification. The size, contour, shape, density and enhancement of the tumors on CT were assessed. Presence of mediastinal lymphadenopathy, great vessel invasion, metastasis to the lung or plural, myasthenia gravis (MG) were also analyzed. The survival rate was obtained using the Kaplan-Meier method. The Cox model was applied to determine the factors affecting the tumor-related survivals. Chi square test was used to analyze the relationship between CT findings and WHO classification. Results Two patients were excluded because of dying of myocardial infarction and colon cancer. The total 5-year survival rate was 84.3%(n=75). Eighty-nine patients had total 91 tumors. Tumors with diameter larger than 5 cm, lobular contour, heterogenous density, and presence of great vessel invasion, mediastinal lymphadenopathy, and metastasis were adverse factors which could significantly affect the survival time. Five-year survival rates of these factors were 72.7%, 77.3%, 76.7%, 73.8%, 30.0%, and 68.8%, respectively. Presence of MG was a favorable factor which also significantly affected the survival time (P＜0.05). While the shape and enhancement of the tumors and the age, gender of the patients did not significantly affect the survival time (P＞0.05). The result of the Cox multivariate analysis was consistent with that of the Log-rank test. For different WHO classification, there were significant different among the size or contour of the tumors, presence of great vessel invasion, mediastinal lymphadenopathy, and metastasis (x2 value were 6.598, 5.737, 18.307, 8.465, and 15.608, respectively P＜0.05). Conclusions CT findings may be served as predictors of clinical prognosis of the thymic epithelial tumors. Adverse factors for survival time are the size of the tumors and presence of mediastinal lymphadenopathy, while MG is a favorable factor for survival time.

ObjectiveTo investigate the CT findings of thymic epithelial tumors (TETs).Methods The CT images of 133 cases with TETs confirmed pathologically were reviewed retrospectively.The TETs were reclassified according to WHO 2004 Classification System.The CT features of different histopathological types of TETs were analyzed.The frequencies of demonstrating these CT features were compared between different types using Chi-square exact test.ResultsType A(9/10,90.0％),AB(15/17,88.2％),B1 (10/13,76.9％ ),and B2( 31/46,67.4％ ) tumors were more likely to have spherical or oval shapes and smooth contours on CT.TETs with irregular or lobular contours were mostly seen in type B3 (21/30,70.0％ )and thymic carcinoma (15/17,88.2％ ).TETs with cyst and necrosis formation were common in type A(6/10,60％ ),B3 ( 19/30,63.3％ ) and thymic carcinoma ( 15/17,88.2％ ).Calcification was more frequently seen in type B2 and B3 (32/76,42.1％ ) than any other type ofTETs (8/57,14.0％ ;x2 =12.20,P ＜ 0.01 ).Type A,AB,B3 and thymic carcinoma had higher prevalence of significant enhancement (39/74,52.7％) than type B1 and B2 (8/57,13.6％;x2=22.01,P＜0.01).ConclusionAccording to WHO 2004 histologic classification system,different types of TET have corresponding CT features.CT has showed the potentiality in differentiating histological subtypes of TETs.

Objective To study the ches t X-ray and CT appearance of pulmonary nontuberculosis mycobacteria (NTMB) Methods The chest X-ray findings of 22 cases with cultures positive for pulmonary nontuberculosis mycobacteria were reviewed, 10 cases had CT scans simultaneously All abnormalities and predominant lobar involvement were recorded The findings of chest X-ray and CT were compared Results The chest X-ray showed that air space consolidation ( n =19) and cavities ( n =18) were most frequently seen, nodules ( n =12) and linear disease ( n =14) were observed too The abnormalities involved bilateral multiple lobes, the right lung was more frequently involved than left, and upper lobe was involved more than lower ones Multiple manifestations were often co-existing ( n =19) On CT scans, nodule was the most frequent finding ( n =10), air space consolidation ( n =8) and cavity ( n =8) were other common findings In addition, bronchiectasis ( n =5), “tree in bud” sign ( n =3), and mediastinal lymphadenopathy ( n =2) were also seen on CT but not on chest X-ray Conclusion Air space consolidation, cavity, nodule, fibrosis, bronchiectasis, and “tree in bud” are major abnormalities of chest image The image abnormalities of pulmonary NTMB are indistinguishable from those of secondary pulmonary TB Multiple co-existing manifestations may be the characteristic findings of pulmonary NTMB infection

Objective To analyse the CT findings of Bochdalek hernia in adult.Methods The CT scan of 42 cases were reviewed showing a mass abutting the upper surface of the diaphragm, the defect was located in the posteromedial aspect of hemidiaphragm with continuity of subdiaphragmatic and supradiaphramatic densities through the diaphramatic defect. Among these, 25 cases were male and 17 cases female. The average age was 64 years, 71.4%≥60 old.Results 53 Bochdalek hernias were identified in 42 cases, 11 cases were bilateral, 21 cases were on the left and 10 cases were on the right side. The diaphragmatic defects diameter ranged 0.5～6.7 cm, the median was 2.8 cm. The range of Bochdalek hernias diameter was 1.5～9.0 cm, with median of 3.7 cm. There was a significant association between diaphragmatic defects and size of hernias (r s=0.72,P

To evaluate the features of mediastinal tuberculous lymphadenopathy in adults on CT, especially on enhanced CT scan. Methods Seventeen patients with adult mediastinal tuberculous lymphadenopathy proved by operation, biopsy, and (or) anti tuberculous therapy were evaluated on chest film and CT scan, and 6 patients were performed with enhanced CT scan. Results The chest film finding was intrathoracic mass and (or) hilar mass only in 6 patients, but CT detected 37 enlarged nodes in all patients. Most of the enlarged nodes were located in 2R and (or) 4R (59.4%). 30 nodes (81 1%) presented as low density in the center of nodes, and there were marked enhancement at the periphery areas of the nodes after enhancement in all 6 patients (100 0%). Conclusion CT scan, especially the enhanced CT scan, is the first method of choice to diagnose the mediastinal tuberculous lymphadenopathy in adults.

Objective To evaluate the role of CT or Chest radiograph in diagnosis of chest wall tuberculosis.Methods The study population included 21 patients with chest wall tuberculosis confirmed by operation or biopsy. Chest radiograph and plain CT were performed in all cases, while enhanced CT in 9 cases , and all images were reviewed by 2 radiologists.Results Single soft tissue mass of the chest wall was detected in all cases on CT, but not on chest radiograph(?2=42.000,P

Objective To study the CT features of thoracic sarcoidosis in senile and pre senile patients. Methods The findings in 25 patients(14 elderly patients and 11 pre senile patients) manifesting thoracic sarcoidosis were reviewed. Results Nine patients with typical findings and sixteen patients with atypical findings were reported at retrospective presentation. The atypical patterns at CT included mediastinal adenopathy with unilateral hilar adenopathy( n =3, 3/25), mediastinal adenopathy alone ( n =7, 7/25), unilateral hilar adenopathy alone ( n =1, 1/25), and lung abnormal findings without any mediastinal and/or hilar adenopathy ( n =5, 5/25). The latter 5 patients were misdiagnosed at the first clinical consultation. Conclusions The thoracic sarcoidosis in the elderly often manifests atypical patterns, and the recognition of the key point is of importance and helpful for the definite diagnosis.

Objective To study the CT appearances in the atypical thoracic sarcoidosis Methods Chest CT findings of 43 patients with proven sarcoidosis were reviewed retrospectively Results 22 cases (51 16%) had atypical thoracic sarcoidosis findings at presentation The atypical patterns on CT included mediastinal adenopathy alone ( n =9) or in combination with unilateral hilar adenopathy ( n =6), and unilateral hilar adenopathy alone ( n =1) 6 patients had abnormal findings in the lung alone without adenopathy, and they all had been misdiagnosed 18 atypical cases (81 82%) occurred in patients older than 50 years, whereas 4 atypical cases (18 18%) occurred in patients younger than 50 years Conclusion Half patients with thoracic sarcoidosis have atypical CT appearances, it frequently occurs in elderly patients, and the diagnosis is easily mistaken on CT scan

Objective To study the conventional CT and HRCT manifestations of adult mycoplasma pneumoniae pneumonia. Methods Conventional CT and HRCT were performed in 16 adult patients with mycoplasma pneumoniae pneumonia proven by serology. The CT images were retrospectively analyzed. Results Areas of ground glass opacity(GGO)were found in 12 cases. GGO showed lobular or patchy distribution in 9 cases. Air space consolidation was observed in 8 cases,"tree in bud" sign in 9,thickening of the interlobular septa in 3,and thickening of bronchovascular bundle in 1. 15 cases had two or more findings simultaneously. Conclusion Mycoplasma pneumoniae pneumonia has some characteristic CT findings, which can help to distinguish it from bacterial pneumonia.

Objective To assess the val ue of 18-fluorodeoxy glucose (~18F-FDG) positron emission tomography( PE T)-CT in the detection of malignant bone metastases. Methods Thirty-five out of 332 patients, 89 lesions were detected on ~18 F-FDG PET-CT and were interpreted separately on PET, combined CT, and fused PE T-CT images. Results Of the 89 lesions detected on PET- CT images, 68 were malignant and 21 were benign lesions. PET alone identified 62 malignant lesions and 17 benign lesions. The diagnostic sensitivity, specificit y, and accuracy of PET alone for diagnosis of bone metastases were 91.2% (62/68) , 81.0% (17/21), and 88.8% (79/89), respectively. The combined CT alone identifi ed 55 malignant lesions and 16 benign lesions. The diagnostic sensitivity, s pecificity, and accuracy of combined CT alone were 80.9% (55/68), 76.2% (16/21), and 79.8% (71/89), respectively. The fused PET-CT images identified 64 maligna nt and 19 benign lesions. The diagnostic sensitivity, specificity, and accuracy of the fused PET-CT were 94.1% (64/68), 90.5% (19/21), and 93.2% (83/89), respe ctively. Conclusion In the diagnosis of bone metastases, ~18F-FDG PET-CT imaging reduces the false positive rate and increases the specificity. ~18F-FDG PET-CT imaging is helpful in the differentiation o f bone metastases from benign lesions.