Illustration for whole procedure of stone extraction. A: The intrasinusal pelvis was incised according to the shape and location of the stone. P represents pelvis. B: The stone was made free from mucosal adhesions with forceps. S represents stone in the pelvis. C: A flexible ureteroscope was inserted from the trocar under the twelfth rib and through the pelvis incision to search for the residual stones. U represents ureterscope. D: A large stone was removed by stone basket. E-F: Intraoperative and postoperative abdominal x-ray was used to confirm stone clearance.