Instrument for penetrating body tissue

摘要

An instrument (54) for the direct penetration of body tissue comprises an elongated rigid hollow shaft (56). A point (60) at the distal end of the shaft (56) is shaped to penetrate body tissue, to create an opening therein and to enlarge the opening as the point (60) is advacend into the body tissue. The distal end portion (70) of the point (60) is capable of transmitting images received back from the surgical site in advance of and laterally of the point (60). The point (60) has a cutting element (68a-68d) to enable the point (60) to pierce and cut the tissue. In the hollow shaft (56) lighting means and light image receiving means are provided.