An apparatus includes a body and a pair of rigid legs extending from the body. The body includes an engagement feature configured to engage a deployment instrument. The legs are parallel with each other. Each leg has a sharp tip. The legs both extend along a plane. The body defines a guide opening. The guide opening is oriented transversely relative to the plane associated with the legs. The guide opening is sized to receive a cannula having a generally flat profile. The guide opening is configured to guide the cannula through a sclerotomy at a substantially tangential orientation.