Endoscopic microsurgical instruments

Abstract

Microsurgical instruments for performing extremely small-scale, minimally-invasive microsurgery such as thoracoscopic coronary artery bypass grafting. The instruments utilize a symmetrical, forcep-like actuator which provides extremely precise actuation and control of the instrument and which mimics the feel of instruments used in conventional open surgical procedures. The instruments generally include a pair of coaxially arranged shafts, an end-effector at the distal ends of the shafts, and an actuator at the proximal ends of the shafts. The actuator includes a pair of arms pivotally coupled to one of the outer and inner shafts, and a pair of links pivotally coupled at one end to the arms, and at a second end to the other of the shafts. The links are coupled to a proximal portion of the arms to maximize mechanical advantage and reduce interference. The actuator may be easily adapted for either pull-type or push-type actuation, and for either outer shaft or inner shaft translation. The actuator is provided with a locking mechanism for fixing the relative position of the shafts to maintain the end-effector in a closed position. The locking mechanism includes rigid catches that are engaged upon actuation of the actuator and are disengaged upon further actuation of the actuator. The end-effectors may have a variety of configurations, including needle drivers, forceps, scissors, and clip appliers.