SYSTEMS AND METHODS FOR DISSECTING TISSUE

Systems and methods are provided for separating layers of tissue along planes by delivering a gas, such as CO2, under pressure to the tissue. An instrument for dissecting tissue comprises an elongate shaft with a proximal end configured for coupling to an external source of gas and an open distal end fluidly coupled to the proximal end. An internal reservoir containing CO2 under pressure is disposed within the instrument and a valve is coupled to the internal reservoir to open and close an outlet of the reservoir, thereby allowing the CO2 from the internal reservoir to flow through the internal lumen and to a target site within the patient. The internal reservoir of gas allows the CO2 to be delivered to the target site at a substantially higher flow rate, which increases the performance of the device in separating tissue layers.