An optical obturator for penetrating tissue includes an outer member defininga longitudinal axis and having proximal and distal ends, a leading member disposedadjacent the distal end of the outer member and having an optical window adaptedto permit passage of light therethrough for detection by a clinician, and a penetratingmember mounted adjacent the leading member and having a penetrating surfaceadapted to facilitate penetrating of tissue. The leading member is adapted forlongitudinal movement between a first longitudinal position and a second longitudinalposition. The penetrating surface of the penetrating member is at least partiallyexposed upon movement of the leading member from the first longitudinal positionto the second longitudinal position.
