Devices, systems and methods for delivering fluid to tissue

Abstract

In one aspect of this invention, control systems are provided for controlling the inflation of a tissue tensioner or balloon for a fluid delivery system, such as for a needleless fluid injection device. In another aspect of the invention, a system for reducing the response time for jet injection of fluid is provided. In yet another aspect of the invention, systems and devices are provided for controlling the volume of fluid that is ejected from a fluid injection system, which systems include at least one stop that is selectively rotated to limit the movement of a shaft in a linear direction, thereby controlling the amount of fluid that is ejected from the system.

1 - 7 . (canceled) 
     
     
         8 . A fluid injection system comprising:
 a shaft comprising a proximal end, a distal end, and at least one protrusion extending from an outer surface of the shaft adjacent the proximal end; and   a first rotatable, stepped stop member comprising multiple grooves, wherein the stop member is positioned concentrically around the shaft, and wherein the shaft is linearly moveable in a distal direction for engagement of the at least one protrusion with at least one of the multiple grooves.   
     
     
         9 . The fluid injection system of  claim 8 , further comprising a second rotatable, stepped stop member comprising multiple grooves, wherein the first stop member is positioned concentrically around the second stop member. 
     
     
         10 . The fluid injection system of  claim 8 , wherein the first stop member is manually rotatable. 
     
     
         11 . The fluid injection system of  claim 8 , wherein the first stop member is automatically rotatable. 
     
     
         12 . The fluid injection system of  claim 11 , further comprising a motor operatively engaged with the first stop member to provide its automatic rotation. 
     
     
         13 . The fluid injection system of  claim 8 , wherein the multiple grooves are arranged in an angular arrangement around a circumference of the first stop member. 
     
     
         14 . The fluid injection system of  claim 8 , further comprising a second rotatable, stepped stop member comprising multiple grooves, wherein the second stop member is spaced distally along the shaft from the first stop member.