Resection of giant cholesteatoma in the CPA area. Cholesteatoma is a benign tumor, mostly located in the CPA area, or the saddle area, and has a tendency to burrow when it sees a seam. The difficulty in the treatment of giant CPA cholesteatoma is that it is difficult to completely resect the tumor and is prone to intracranial sterile inflammation or delayed intracranial hematoma after surgery. In this case, the standard posterior sigmoid sinus approach was used only for the giant CPA cholesteatoma, and the microscopic angle was repeatedly adjusted under the microscope, and dexamethasone saline was repeatedly flushed with the application of repeated adjustment of scraping ring, scraping spoon and suction, and the tumor was completely resected microscopically.