Patent ID: 8636694

Claim:
A medical injection system, comprising: an elongate injection apparatus comprising: an elongate shaft including a shaft lumen extending from a proximal end of the shaft to a distal end of the shaft, a proximal portion extending distally from the proximal end, and a distal spiral cut portion extending distally from the proximal portion to the distal end of the shaft, the distal spiral cut portion comprising a first segment extending distally from the proximal portion, a second segment extending distally from the first segment, and a spiral cut extending along the first segment and second segment, the spiral cut having a generally exponentially decreasing pitch along the first segment and a generally linearly decreasing pitch along the second segment; and a needle tip coupled to the shaft and extending distal to the distal end of the shaft, the needle tip including a needle lumen extending therethrough and approximately aligned with the shaft lumen; wherein the shaft lumen and the needle tip lumen provide a passage for injection of therapeutic agents; and an actuator apparatus comprising: a fitting for coupling the actuator apparatus to a proximal portion of a delivery catheter, the fitting including a fitting lumen extending therethrough adapted to slidably receive the injection apparatus and to direct the injection apparatus through a lumen of the catheter; and a plunger slidably engaged with the fitting, the plunger including a plunger lumen extending therethrough adapted to slidably receive the injection apparatus and to direct the injection apparatus through the fitting lumen; the plunger further comprises means for reversibly gripping the injection apparatus within the plunger lumen; wherein the plunger slides distally and proximally with respect to the fitting to advance and retract, respectively, the injection apparatus within the catheter lumen when the actuator apparatus is coupled to the catheter and the gripping means grips the injection apparatus.