A system of instruments is provided for vitrectomy surgery, comprising a sharp trochar, a cannula and a cannula valve cap. The sharp trochar provided also has applicability to other fields of surgery. The sharp trochar has a hollow-ground blade that reduces the force necessary for insertion and upon removal leaves a wound with improved healing characteristics. The trochar is selectably insertable in a cannula, and in a preferred embodiment the cannula and the trochar are adapted with mutually tapered exterior surfaces to as to define a smooth transition in diameter to further facilitate insertion. A sealing valve cap is also provided for the cannula, designed to provide sealing while reducing the force required in for inserting instruments into the cannula. A method for angled insertion of this assembly is also disclosed.
