Abstract:

Objective The aim of this study was to assess the differences in microscopic signs of the pulmonary glass nodules between the ultra-high resolution CT (UHRCT) target scan and conventional CT target reconstruction,and analyzed the difference of the two methods in qualitative diagnosis of pulmonary ground glass nodules.Methods From August 2016 through December 2017, 120 cases of suspected pulmonary tuberculosis were screened in Shandong Provincial Chest Hospital, who with a single glass nodule in lung. The patients underwent routine CT scanning, followed by target reconstruction and UHRCT target scanning, a total of 120 nodules.Two experienced radiologists with subtropical high or above physicians,were asked to analyze the two kinds of lung CT image ground glass nodules signs (Margin of nodles, pulmonary markings thickening, solid component, burr fin,bubble sign, air bronchogram, pleural pull) respectively, the diagnosis of precancerous lesions (AAH, AIS), microinvasive adenocarcinoma (MIA) and infiltrating adenocarcinoma (IAC) were determined, and the accuracy of the diagnosis of lung adenocarcinoma by two methods was compared according to the pathological results. In this study, Chi square test was used in SPSS 17.0 statistical software, and P<0.05 difference was statistically significant.Results Margin of nodule, UHRCT target scanning was 71 (78.0%), and CT target reconstruction was 56 (61.5%) (χ ²=5.863, P=0.015). Thickening pulmonary markings, the UHRCT target scanning was 60 (65.9%), and the CT target reconstruction was 45 (49.5%)(χ ²=5.065, P=0.024). Solid component,the UHRCT target scanning was 66 (72.5%), and the CT target reconstruction was 50 (54.9%) (χ ²=6.086, P=0.014). Burr fin, the UHRCT target scanning was 34 (37.4%), and the target reconstruction of CT was 29 (31.9%) (χ ²=0.319, P=0.572). Bubble sign, UHRCT target scanning was 22 (24.2%), CT target reconstruction was 18 (19.8%) (χ ²=0.513, P=0.474).Air bronchogram, UHRCT target scanning was 28 (30.8%) and CT target reconstruction was 26 (28.6%) (χ ²=0.105, P=0.746). Pleural indentation, UHRCT target scanning is 30 (32.9%),and CT target reconstruction was 21 (23.1%) (χ ²=2.207, P=0.137).The number of the pathologic coincidence CT target reconstruction was 75 (82.4%) and discrepancy was 16 (17.6%). The number of the pathologic coincidence UHRCT was 86 (94.5%) and discrepancy is 5 (5.5%). Chi-square test, χ ²=6.513, P=0.011. Conclusion The target scan of UHRCT is more clear than that of conventional target reconstructed images, and it is helpful for pathological stages of pulmonary glass nodules.

Key words: Solitary pulmonary nodule, Tomography, X-ray computed, Image processing, computer-assisted, Diagnostic imaging, diagnostic techniques and procedures, Comparative study