Small, ground glass nodules in the lung need to be highly alert if their diameter is >5mm; if they are >10mm and have risk factors, such as smoking and family history of lung cancer, surgery is recommended as soon as possible; if the nodules are relatively small and have risk factors, <4mm can be reviewed within 1 year; around 4-6mm, it is recommended to review them in 6-8 months, and then 1 or 2 years for follow-up review; for nodules of 6-8mm, it is recommended to review them every 3 months. It is recommended to review every 3 months, i.e. 3 months, 6 months, 9 months and 1 year. The prerequisite for follow-up review is that there is no significant change in the nodule, no physical discomfort and no change in the imaging review. It should be noted that all the films should be brought to each review for comparison. When comparing the first with the second, the second with the third, or even the fourth with the fifth, the changes may not be obvious, but when comparing the first with the last, there may be changes.