RESUMEN
With large CPA tumor(>3 mm), brain stem is usually displaced and distorted to contralateral side. It is important minimize retraction to protect brain stem and to lower morbidity. In our previous report, we reported the result and method of combined approach for large CPA tumor. In order to minimize brain stem retraction and to get good operating field, three of 7 cases of large CPA tumor with combined approach were operated with sacrifice of sigmoid sinus. The sigmoid sinus can be sacrificed if it can be angiographically verified that the sagittal sinus represents the major drainage to the contralateral sigmoid sinus. During operation, if pressure difference between before and after occlusion of sinus is less than 10 mmHg and any brain swelling does not develop after occlusion, the sigmoid sinus can be sacrificed.