RESULTS: About 1cm small round GGO nodule was found in CT image. Location: right upper lobe 2 cases, right middle lobe 1, left upper lobe 2. HRCT or 3DCT showed detailed information. Density: three cases showed heterogeneous density, mixed GGO (mGGO); the other two pure GGO (pGGO). Shape and margin: three mGGO showed lobulated margin. Spiculation: in three mGGO. Pleural indentation: in two mGGO and one pGGO. Vascular convergence: crab claw sign, or called crab claw like vascular convergence, which is usually showed in CT image of peripheral lung adenocarcinoma, now showed in HRCT image of GGO, including crab chela sign: in the CT image, two small blood vessels converge to the tumor from two sides, just like a crab is stretching its chelipeds using its chela clamping the tumor, showed in the five cases; crab foot sign: in the CT image, one small blood vessel converge to the tumor from one side, just like a crab is stretching one of its walking legs reaching and hooking the tumor, showed in five cases. One pGGO was diagnosed MIA, the other one AIS; the two mGGO were diagnosed AIS, and the other one MIA.