The purpose of positioning is to remove as much tumor material as possible, and to remove as little lung tissue as possible. Generally, CT is required for positioning during lung surgery, and the tumor material can be accurately cut out after clear positioning. Especially for early tumor material, such as ground glass nodules, ground glass nodules are a kind of precancerous lesions, but the density of nodule-like masses is relatively small and the edges are not too clear, so CT positioning can accurately determine the edges and remove the nodules as much as possible during the surgery, preserving as much lung tissue as possible.