Objective:To investigate the relationship between amylase level in drainage fluid and the risk of salivary fistula(SF)after parotid benign tumor resection.Methods:106 patients underwent benign parotid tumor resection were included and divided into SF occurrence group(SF,n=31)and non-occurrence group(control,n=75).The amylase levels of drainage fluid were com-pared between the 2 groups at 24,48 and 72 h respectively after surgery,and the risk factors related to postoperative salivary fistu-la were evaluated by multivariate Logistic analysis and ROC curve.Results:The content in amylase in drainage fluid at 24,48 and 72 h after operation and partial retention of parotid masseter fascia during operation in the SF group were higher than those in the control group(P＜0.05),and the postoperative compression time was shorter than that in the control group(P＜0.05).Multiva-riate Logistic analysis showed that the amylase content of drainage fluid at 24,48 and 72 h and the complete preservation of parotid masseter fascia during operation were the influencing factors for the occurrence of postoperative SF(P＜0.05).The ROC curve showed that the AUC of amylase level of drainage fluid in predicting the risk of postoperative SF was 0.979(95％CI 0.930-0.997)at 72 h after surgery.Conclusion:The level of amylase in the drainage fluid is associated with the risk of SF after benign parotid tumor resection.The level of amylase in the drainage fluid 72h after benign parotid tumor resection can accurately predict SF after benign parotid tumor resection.

Objective:To investigate the relationship between amylase level in drainage fluid and the risk of salivary fistula(SF)after parotid benign tumor resection.Methods:106 patients underwent benign parotid tumor resection were included and divided into SF occurrence group(SF,n=31)and non-occurrence group(control,n=75).The amylase levels of drainage fluid were com-pared between the 2 groups at 24,48 and 72 h respectively after surgery,and the risk factors related to postoperative salivary fistu-la were evaluated by multivariate Logistic analysis and ROC curve.Results:The content in amylase in drainage fluid at 24,48 and 72 h after operation and partial retention of parotid masseter fascia during operation in the SF group were higher than those in the control group(P＜0.05),and the postoperative compression time was shorter than that in the control group(P＜0.05).Multiva-riate Logistic analysis showed that the amylase content of drainage fluid at 24,48 and 72 h and the complete preservation of parotid masseter fascia during operation were the influencing factors for the occurrence of postoperative SF(P＜0.05).The ROC curve showed that the AUC of amylase level of drainage fluid in predicting the risk of postoperative SF was 0.979(95％CI 0.930-0.997)at 72 h after surgery.Conclusion:The level of amylase in the drainage fluid is associated with the risk of SF after benign parotid tumor resection.The level of amylase in the drainage fluid 72h after benign parotid tumor resection can accurately predict SF after benign parotid tumor resection.