Thin-layer CT is a type of CT with higher resolution and has been widely used in the diagnosis of tumors. Thin-layer CT and plain CT are both CT examinations, the biggest difference is that the scanning layer is not the same thickness, so the imaging resolution and the detection rate of lesions are also different. The differences between thin-layer CT and plain CT are as follows: 1. different scanning layers: thin layer CT adopts layer thickness of 1.5-5mm, while ordinary CT scanning adopts layer thickness of 8-10mm, so thin layer CT has higher resolution. 2. Convenience difference: ordinary CT has the advantages of convenient operation, short time-consumption, and lower detection cost, etc. Most of the patients are examined by ordinary CT, and only when they are suspected of having lung foci or other small foci will they use thin-layer CT for further confirmation. 3. Different detection rates: Thin layer CT has a higher detection rate than plain CT. Because the accuracy of plain CT is a little lower, the detection rate of small lesions is different, such as for the small grinding glass-like shadow in the lungs usually use thin-layer CT examination. 4. Difference in radiation dose: Thin-layer CT has a higher radiation dose than plain CT. Although thin-layer CT has higher resolution, clinical diagnosis often needs to rely on a variety of tests to comprehensively assess the condition. If there is any abnormality, suspicion or diagnosis of tumor, it is recommended to go to regular hospitals for comprehensive evaluation of the condition, diagnose and evaluate the disease by a variety of means, and cooperate with the treatment as prescribed by the doctor, so as to avoid delaying the condition.