Patent ID: 8216246

Claim:
A probe for a vitrectomy tool comprising: a vitreous cutter tube having a blunt tip at a distal end and adapted to be coupled at a proximal end to a handpiece of a vitrectomy tool, wherein the vitreous cutter tube comprises an aperture extending into a central bore, the vitreous cutter tube comprising a reciprocal cutter fitted in the central bore having a cutting edge adapted for travel across the aperture adapted to receive a flow of vitreous material, and a valve assembly operatively positioned between the vitreous cutter tube and a variable volume cavity in the handpiece and arranged to open to apply a negative pressure to the vitreous cutter tube central bore when the reciprocal cutter travels across the aperture; a retractable outer trocar tube surrounding the vitreous cutter tube having an open distal end with a sharpened edge; and a retraction mechanism coupled to a proximal end of the outer trocar for selectively extending and retracting the outer trocar tube between a first extended position wherein the sharpened edge of the outer trocar is extended beyond the blunt tip of the vitreous cutter tube to facilitate insertion into the eye and a second retracted position wherein the sharpened edge of the outer trocar is retracted behind the blunt tip of the vitreous cutter tube to facilitate safe operation of the probe.