Syringe with volume displacement apparatus

A syringe system for delivering fluid so as to control inflation and deflation of a balloon located at a distal end of a dilation catheter comprising:

• a syringe comprising a barrel adapted for connection to a delivery means for fluid communication with a balloon of a dilation catheter and a plunger selectively operable to inflate and deflate the balloon by applying fluid pressure to the balloon by sliding the plunger within the barrel;
• delivery means, connected in fluid communication with the syringe for communicating fluid from the syringe to the balloon, the delivery means comprising tubing;
• pressure sensing means for sensing fluid pressure applied by the plunger, said pressure sensing means being placed in fluid communication with said syringe and the tubing connected thereto;
• display means coupled to the pressure sensing means, for displaying in a visually perceptive manner the applied fluid pressure sensed by the pressure sensing means;
• and
• means in fluid communication with said barrel for manual volume displacement by expelling a fixed volume of fluid from said barrel into the balloon, thereby inflating the balloon by a reproducible amount when activated and returning the balloon to the previous position when deactivated by permitting return of the same fixed volume of fluid when released.

A syringe system for delivering fluid so as to control inflation and deflation of a balloon located at a distal end of a dilation catheter comprising:

• a syringe comprising a barrel adapted for connection to a delivery means for fluid communication with the balloon of a dilation catheter and a plunger selectively operable to inflate and deflate the balloon by applying fluid pressure to the balloon by sliding the plunger within the barrel;
• delivery means, connected in fluid communication with the syringe, for communicating fluid from the syringe to the balloon, the delivery means comprising tubing;
• pressure sensing means for sensing fluid pressure applied by the plunger, said pressure sensing means being placed in fluid communication with said syringe and the tubing connected thereto;
• display means coupled to the pressure sensing means, for displaying in a visually perceptive manner the applied fluid pressure sensed by the pressure sensing means;
• and
• button means mounted on the barrel in fluid communication with the barrel, for expelling into the balloon a fixed volume of fluid from the barrel by activating a button so as to inflate the balloon by a predetermined amount, and recovering the fixed volume of fluid when the button is deactivated, thereby deflating the balloon by the same predetermined amount.

In a system comprising an inflatable balloon member connected through tubing to a syringe barrel and wherein a plunger slidably mounted within said barrel is movable to selectively apply and then release fluid pressures exerted on said balloon member so as to selectively inflate and deflate said balloon member one or more times, a method for selectively inflating and deflating the balloon member in a pulsatile fashion comprising:

• a) establishing a fluid pressure applied to the balloon member by depressing said plunger within said syringe barrel immediately below the pressure required to inflate the balloon member;
• b) manually activating a means in fluid communication with the barrel, for selectively displacing a fixed volume of fluid from the barrel thereby inflating the balloon member to a predetermined amount;
• and
• c) deactivating the means for selectively displacing a fixed volume of fluid from the barrel in order to permit deflation of the balloon member by the same predetermined amount.