Three-dimensional (3D) simulation of pulmonary vessels and the space between the lesion and adjacent tissues is regarded improving the safety and accuracy of video-assisted thoracoscopic surgery (VATS) for segmentectomy for ground glass opacity (GGO) in lung. However, not every thoracic surgeon can handle the technique, in addition, the 3D reconstruction originate from the thin CT scan. Actually, the investigators found that, the reading and comprehension of the thin cross- section of CT can guide the accurate anatomic segmentectomy in most situations. The investigators designed a retrospective study to compare the reading of thin cross- section of CT with 3D reconstruction or without 3D reconstruction during the guidance of anatomic segmentectomy.

Inclusion Criteria:

Selection criteria for VATS segmentectomy in the present study were as follows:

(I) patients with single peripheral GGO lesion considered suspicious for malignancy;

(II) the lesion <2 cm in diameter and with at least one of the followings:

(i) pure adenocarcinoma in situ (AIS) histology;

(ii) nodule has ≥50% ground-glass appearance on high resolution CT;

(iii) radiologic surveillance conforms a long doubling time (≥400 days).

Exclusion Criteria:

(I) patients with insufficient cardiopulmonary function;

(II) other contraindication for segmentectomy.