Abstract: The experiment were carried out on 20 cats,to observe the cerebral injury of different CUSAcondition.The area of encephaledema and blood-brain barrier （BBB） lesion was determined.Theresults indicated:1 the strengths of aspiration and fragmentation are main factors of injury,espec-ially the former;2 the irrigation rate appears no obvious impact.The authors also discuss the useof CUSA in opration.