An optical obturator apparatus includes an obturator sleeve defining a longitudinal axis and having a longitudinal bore for receiving surgical instrumentation and a transparent window mounted to the obturator sleeve and being dimensioned and configured to pass through tissue. The transparent window is mounted for movement between a first position in general alignment with the longitudinal axis of the obturator sleeve and a second position radially displaced from the longitudinal axis to thereby expose the longitudinal bore of the obturator sleeve to permit passage of the surgical instrumentation. The transparent window may include a cutting blade, or alternatively two cutting blades, adapted to penetrate tissue.