摘要
Objective:The aim of our study was to observe the different effects including diameter of cryosurgery region and incidence of pneumothorax and pleural effusion when cryosurgery upon the pulmonary parenchyma with single or double freeze-thaw cycles in rabbits.Methods:Fifty rabbits were divided into two groups and they were all subjected to cryosurgery.The group one was single freeze-thaw cycle cryosurgery and the other group was double cycles.Pneumothorax and pleural effusion were observed after cryosurgery immediately with computer tomograph.The surviving animals were killed at 3 days after cryosurgery and histology observe were obtained.Results:There was no animal dead in the test.Histologically,a hemorrhagic infarct developed in the region of cryosurgery.The incidence of pneumothorax was 28% in group one and 12% in group two.The diameter of cryosurgery region was(4.3 ± 0.8) cm in rabbits who received double cycles cryosurgery and 3.1 ± 0.8 cm in single cycle.Conclusion:It is safety to cryosurgery upon pulmonary parenchyma with one or two cycles and the histological changes are similar.The diameter of cryosurgery region with two cycles was bigger than one.