Frosted glass nodules of the lung are imaging changes that occur pathologically in focal lung tissue, causing a decrease in the air content of the lung tissue, before the alveoli have completely atrophied. They resemble frosted glass on CT. It is an early stage of lung tissue lesion and the pathological process is sometimes reversible. It can be caused by infectious diseases, fibrosis, and tumors. High resolution CT with 1.0mm tomography is the best imaging method to detect, visualize, and analyze frosted glass nodules. Pulmonary ground glass nodules are divided into: 1. pure ground glass nodules with uniform density, which can be inflammation, focal hemorrhage, adenoma-like atypical hyperplasia (precancerous lesions); 2. partially solid ground glass nodules with complete alveolar atrophy and tissue hyperplasia showing uneven density, which can be benign tumors, carcinoma in situ or adenocarcinoma, with malignancy rate of more than 60%. Therefore, partially solid ground glass nodules should be given full attention. Clinical management guidelines 1. Isolated pure pure ground glass nodules less than 5 mm in diameter can be followed up every year because of their pathologic possibility of adenomatous atypical hyperplasia and few are adenocarcinoma in situ. The scan layer thickness must be 1 mm to determine whether they are true pulmonary ground glass nodules. Elderly people may not be followed up. 2. Isolated, pure ground glass nodules larger than 5 mm in diameter are reviewed after 3 months to observe for changes in the lesion. If they persist, they are reviewed annually for at least 3 years. 10 mm or larger ground glass-like nodules are reviewed after 3 months, and if there is no change, they should be treated surgically. The ground glass nodules may be pathologically adenomatous atypical hyperplasia, adenocarcinoma in situ and a small percentage of microinfiltrating adenocarcinoma. Therefore, antibiotics are not recommended, PET-CT is of little value, and CT-guided lung puncture is not recommended because of the low positive rate. If the nodule is enlarged or the nodule density is increased, minimally invasive surgical treatment is available, and we use thoracoscopic lung wedge resection or lung segmental resection. Intraoperative cryopathological examination is done. 3. Partially solid density ground glass nodules with a diameter of less than 8 mm are reviewed at 3, 12 and 24 months, if the solid part increases to be treated surgically, and those with a diameter greater than 8 mm are reviewed at 3 months, if there is no change should be treated surgically, including minimally invasive thoracoscopic lung wedge, lung segment and lobectomy. Most of the large pure GGO are aggressive lesions. 4, Multiple pure ground glass nodules with well-defined margins less than 5.0 mm should be treated with a more conservative regimen, and follow-up at 2 and 4 years is recommended. 5, Multiple pure ground glass-like nodules with at least one lesion larger than 5.0 mm but no particularly prominent lesions are recommended for review after 3 months and long-term follow-up for at least 3 years. 6. Multiple ground glass nodules with prominent lesions (solid component greater than 5.0 mm, with burr sign and vacuole sign) require surgical management of the main lesion; or if the lesion persists after 3 months of review, surgical management of the larger lesion is recommended, with the recommended procedure being thoracoscopic wedge surgery or lung segmental resection. Postoperative patients are followed annually for at least 3 years. However, do not overtreat ground glass density nodules in the lungs.