A positioning device is provided for delivering or guiding a surgical device into a lumen of a body vessel to a position adjacent target tissue. The device includes a housing, an elongate sleeve, and a source of pressurized fluid. The sleeve has a first end coupled to a delivery side of the housing, a second end positioned on a return side of the housing, and an inverted distal portion positioned between the first and second ends. One second end of the sleeve can be furled about a support member supported on the housing. A distal portion of the sleeve defines a cavity that communicates with a pressure chamber within the housing. When pressurized fluid is directed into the pressure chamber, the pressurized fluid flows into the cavity of the distal portion of the sleeve to advance the sleeve away from the housing.
