Ascites is extracted by ultrasound-guided localized puncture. The pathology department mainly performs diagnostic ascites examination, where the patient can drain the ascites through a puncture needle under ultrasound localization, and then send the ascites to be examined for the appropriate cytological examination. Ascites are processed by centrifugation, because the viscosity of ascites is relatively thin and the density of cellular components is low. After centrifugation and sedimentation of the cells, it is determined whether the cells in the ascites are tumorigenic or non-tumorigenic based on the cellular composition, thus determining the cause of ascites for diagnostic purposes.