PURPOSE: A cannula is provided to easily secure a space for surgical operation while protecting organs and cells in case amount of a target cell for elimination is many and area of a surgical site is wide.CONSTITUTION: A plurality of protrusions(110) is projected along the outer circumference of a body rod(100). The plurality of protrusions is projected from the outer circumference of the body rod and secures a safe operation range and a space in the surgical operation. A protrusion accomplishing a first row and a protrusion accomplishing a second row are arranged as zigzag shape. A plurality of suction slits(101) penetrated along the outer circumference of a closed tip-end part is formed on the body rod. A feed port supplies fluid from a tank to an expansion part through a hydraulic motor.COPYRIGHT KIPO 2012본 발명에 따른 캐뉼라는 몸체봉의 외주면을 따라 타원구(楕圓球) 형상인 복수의 돌기가 마련되며, 전술한 돌기는 타원구의 장축방향을 따라 절단된 면이 전술한 몸체봉에 접하는 형상으로 이루어지고, 전술한 돌기는 타원구의 장축이 상기 몸체봉의 길이 방향과 평행한 구조이다.
