Patent attributes
An apparatus and method are described for actuating a minimally invasive medical device using fluid pressure. The invention involves a medical device that includes a fluid source, such as a compressible bladder that may apply positive fluid pressure into a sheath to controllably deploy an end-effector from a distal end of the sheath. In some embodiments, the fluid source may apply negative fluid pressure into the sheath to controllably retract the end-effector into the distal end of the sheath. Typical end-effectors for use with the medical device of the invention include biopsy devices and retrieval devices, including basket-type retrieval devices and grasper retrieval devices. Generally, the fluid that is used to actuate the device may be a liquid or a gas, including air.