Abstract: Objective To improve diagnosis and differential diagnosis of local pulmonary consolidation lesions with CT imaging characteristics analysis. Methods We analyzed retrospectively CT imaging characteristics of local pulmonary consolidation in patients who admitted in Beijing Chest Hospital from Jan. 2009 to Dec. 2013. All patients were diagnosed definitely with CT guided percutaneous biopsy pathology. Data were analyzed statistically with Chi-square test.  Results （1）Lesions distribution: lesions distribution presented multiple pulmonary segments and solitary pulmonary segment. There were 22 cases（22/36） with pulmonary tuberculosis, 5 cases（5/20） with lung cancer, 5 cases（5/8） with pulmonary lymphoma, 9 cases（9/15） with pneumonomycosis and 2 cases（2/17） with organizing pneumonia in multiple pulmonary segments distribution. However, there were 14（14/36）, 15（15/20）, 3（3/8）, 6（6/15） and 15 cases（15/17） with the different corresponding diseases in solitary pulmonary segment distribution. The difference was significant statistically（χ²＝16.961，P<0.01）. Further analysis showed that the difference was from the statistic significant difference between pulmonary tuberculosis and organizing pneumonia（χ²＝11.348，P<0.005）.（2） Lesions morphology: lesions morphology was divided into segmental consolidation and subsegmental consolidation. There were 30 cases（30/36） with pulmonary tuberculosis, 9 cases（9/20） with lung cancer, 5 cases（5/8） with pulmonary lymphoma, 5 cases（5/15） with pneumonomycosis and 5 cases（5/17） with organizing pneumonia with the segmental consolidation. Meanwhile, there were 6（6/36）, 11（11/20）, 3（3/8）, 10（10/15） and 12 cases（12/17） in the different corresponding diseases with the subsegmental consolidation. The difference was significant statistically（χ²＝20.062，P<0.01）. Further analysis showed that the differences were statistic significant when compared pulmonary tuberculosis with lung cancer, pneumonomycosis and organizing pneumonia, respectively（χ²＝8.936, 12.295 and 14.970，all P values were less than 0.005）. （3）Air bronchogram in main lesion: there were 31 cases（31/36） with pulmonary tuberculosis, 12 cases（12/20） with lung cancer, 7 cases（7/8） with pulmonary lymphoma, 12 cases（12/15） with pneumonomycosis and 5 cases（5/17） with organizing pneumonia with air bronchogram in main lesions, the difference was significant statistically（χ²＝20.536，P<0.01）. Further analysis showed that the differences were statistic significant when compared organizing pneumonia with pulmonary tuberculosis and pneumonomycosis, respectively（χ²＝17.039 and 8.189，all P values were less than 0.005）.（4）Lesion enhancement: there were 22 cases（22/36） with pulmonary tuberculosis, 20 cases（20/20） with lung cancer, 8 cases（8/8） with pulmonary lymphoma, 12 cases（12/15） with pneumonomycosis and 14 cases（14/17） with organizing pneumonia with lesion enhancement. The difference was significant statistically between cases with lesion enhancement and without lesion enhancement（χ²＝14.595，P<0.01）. Compared pulmonary tuberculosis with lung cancer, the difference was statistic significant（χ²＝10.370，P<0.005）. （5）Satellite lesions: the satellite lesions were presented among 34 cases（34/36） with pulmonary tuberculosis, 2 cases（2/20） with lung cancer, 6 cases（6/8） with pulmonary lymphoma, 15 cases（15/15） with pneumonomycosis and 11 cases（11/17） with organizing pneumonia. The difference was significant between cases presented with satellite lesions or not（χ²＝12.067，P<0.01）. Compared lung cancer with pulmonary tuberculosis and organizing pneumonia, the difference was statistic significant, respectively（χ²＝39.933 and 7.968, all P values were less than 0.005）. （6）Diagnostic accordance rate between CT imaging and pathology: compared CT imaging diagnosis with CT guided percutaneous biopsy pathology, the diagnostic accordance rate ranged from 50.0% to 80.6% among these diseases.  Conclusion The characteristics of CT imaging with lesion distribution, morphology, air bronchogram, satellite lesion and lesion enhancement will contribute to certain value for diagnosis and differential diagnosis of local pulmonary consolidation lesions.

Key words: Lung diseases, Tomography, X-ray computed, Biopsy, needle