Cochlear fenestration surgical includes a shaft oriented along the longitudinal axis of rotation of , a cylindrical directed along the axis, thickness, diameter and the contact surfaces a depth stop member having spread from the contact surface to the outside, and the extension member which is coaxial with the axis, and a cutting member having a cutting surface which is supported by the extension member, and there the ends of the cutting member, the cutting surface Located in the center and has a cutting tip which is coaxial with the axis. The maximum cutting depth is defined by the distance along the axis between the contact surface and the ends of the cutting tip. Cutting grit is disposed in the cutting tip and cutting surface on. .BACKGROUND蝸牛開窓手術用穿子は、穿子の回転の長手方向軸に沿って方向づけられたシャフトと、軸に沿って方向づけられた円筒型であって、厚さ寸法、直径寸法及び、接触面を有する深さ止め部材と、接触面から外側に広がり、及び軸と同軸である延長部材と、延長部材によって支えられる切削面を有する切削部材と、及び、切削部材の端部あって、切削面の中央に位置し、軸と同軸である切削チップを有する。最大の切削深さは、切削チップの端部と接触面の間の軸に沿った距離によって定義される。切削グリットは、切削チップ及び切削面上に配置されている。【選択図】図1
