| abstract |
A digital fluid delivery and aspiration apparatus with a mechanical de-amplifier for the delivery or removal of discrete volumes of fluidic material from a surgical site. The apparatus has a syringe with a plunger designed to be powered by a pneumatic air supply system. A ratcheting mechanism attached to a pneumatic piston by a mechanical linkage causes the plunger of the syringe to inject discrete doses of the fluidic material into the surgical site or remove discrete amounts of fluidic material from the surgical site. The mechanical linkage increases the force provided to the plunger by the movement of the piston and also de-amplifies the movement of the piston into a lesser movement of the plunger. Adjusting the waveform of the pneumatic air supply, coupled with the mechanical de-amplification of the movement of the pneumatic piston, reduces the jetting of the fluidic material being delivered, and allows the delivery or removal of precise volumes of fluidic material from the surgical site at precise rates without damaging the tissue into which or from which the fluidic material is being delivered or removed. The irrigation and aspiration features may be incorporated into one device. |