Diagnostic value of spiral CT for pulmonary small isolated nodules with focal ground-glass opacity

Objective To investigate the diagnostic and differential diagnostic value of highresolution multi-slice spiral CT( MSCT) scan for ≤ 1 cm isolated nodules with focal ground-glass opacity( fGGO) in the lung. Methods The features of 93 pulmonary isolated nodules ≤1 cm with f GGO on MSCT were retrospectively reviewed. All lesions were pathologically confirmed,including15 cases of invasive adenocarcinoma,19 cases of micro-invasive adenocarcinoma,52 cases of infiltrated precancerous lesions and 7 cases of inflammatory. The morphology,size,edge,and changes in internal and adjacent structure were observed,and the f GGO ratio of nodular consolidation was assessed. The association of MSCT features with pathological findings was analyzed by χ2test. Results There were significance differences in CT signs of lobulation,glitches and vascular thickening between invasive adenocarcinoma and pre-invasive lesions( χ2= 12. 678,6. 043,7. 147,respectively,P 0. 05). The incidence of transition from pre-invasive to invasive adenocarcinoma was increased with the increasing diameter and consolidation of nodules with f GGO; invasive adenocarcinoma was not found in fGGO nodules 1 cm in diameter. Meanwhile the inflammatory lesions were lacking of characteristics. Conclusion Multi-slice spiral CT scan can provide valuable information for differential diagnosis of pulmonary isolate nodules≤1 cm with focal ground-glass opacity.