Needleless delivery systems

Abstract

Described are devices and methods related to the needleless injection of fluid into tissue of the lower urinary tract, such as the urethra and prostate.

1 . A needleless injector comprising:
 a body at a proximal end;   a first shaft extending distally from the body and having a distal end;   an injection shaft extending from the body and comprising a distal end, the injection shaft being moveable along a length of the first shaft, wherein the distal end of the injection shaft is proximal to the distal end of the first shaft;   an injection orifice at the distal end of the injection shaft in fluid communication with a fluid chamber at the proximal end of the body, the injection orifice being positioned for fluid ejection in a lateral direction relative to a longitudinal axis of the injection shaft and located within the first shaft, wherein the injection orifice is axially moveable along the longitudinal axis;   a pressure source in communication with the fluid chamber; and   an extendable tissue tensioner located at the distal end of the injection shaft proximal to the injection orifice.   
     
     
         2 . The needleless injector of  claim 1 , wherein the needless injector further comprises an injector head at the distal end of the injection shaft, the injector head comprising a flat surface that comprises the injection orifice and a vacuum orifice. 
     
     
         3 . The needleless injector of  claim 1 , wherein the tissue tensioner comprises a retractable tissue tensioner that retractably extends from the injection shaft away from the injection orifice. 
     
     
         4 . The needleless injector of  claim 1 , wherein the injection orifice is located on the injection shaft at a proximal location relative to a distal tip of the injection shaft. 
     
     
         5 . The needleless injector of  claim 1 , wherein the tissue tensioner is located at a length-wise position along the longitudinal axis of the injection shaft on the distal end that is the same as a length-wise position of the injection orifice such that when the distal end comprising the tissue tensioner and injection orifice is placed within a body cavity and the tissue tensioner is extended, tissue of the body cavity is tensioned and the fluid is ejectable from the injection orifice to penetrate tissue under tension. 
     
     
         6 . The needleless injector of  claim 1 , wherein the injector comprises an injector head at the distal end of the injection shaft, the injector head comprising multiple injection orifices. 
     
     
         7 . A method of treating tissue, the method comprising the steps of:
 providing the needleless injector of  claim 1  for insertion into a patient;   inserting the injection shaft into a body cavity so the injection orifice is located adjacent the tissue to be treated;   actuating the tissue tensioner to contact body tissue in a vicinity of the tissue to be treated; and   injecting fluid from the injection orifice directly onto a surface of the tissue to be treated or into the tissue to be treated.   
     
     
         8 . The method of  claim 7 , wherein the step of inserting the injection shaft into the body cavity comprises preparing an external incision and a tissue path leading to the body cavity. 
     
     
         9 . The method of  claim 7 , wherein the step of injecting fluid from the injection orifice comprises injecting the fluid from a pressurized fluid source. 
     
     
         10 . The method of  claim 7 , wherein the step of injecting fluid from the injection orifice comprises ejecting fluid from the injection orifice as a fine, high-pressure stream. 
     
     
         11 . The method of  claim 7 , wherein the step of injecting fluid from the injection orifice comprises injecting the fluid into the tissue as a fine mist of tiny particles. 
     
     
         12 . The method of  claim 7 , wherein the injected fluid is distributed as a fine mist of tiny particles that enter and travel over a range of depths and directions into the tissue. 
     
     
         13 . The method of  claim 7 , wherein treating tissue is selected from the group of tissue consisting of bladder tissue, urethral tissue, kidney tissue, ureteral tissue and prostate tissue. 
     
     
         14 . A needleless injector comprising:
 a body at a proximal end;   an injection shaft extending from the body to a distal end of the injection shaft;   a first shaft extending distally from the body and comprising a longitudinal slot and a distal end, wherein the injection shaft is axially moveable along a longitudinal axis of the first shaft and wherein the distal end of the injection shaft is proximal to the distal end of the first shaft;   an injection orifice at the distal end of the injection shaft in fluid communication with a fluid chamber at the proximal end, the injection orifice being positioned for fluid ejection in a lateral direction relative to a longitudinal axis of the injection shaft and located within the first shaft;   a pressure source in communication with the fluid chamber; and   an expandable tissue tensioner located at the distal end of the injection shaft proximal to the injection orifice.   
     
     
         15 . The needleless injector of  claim 14 , wherein the needless injector further comprises an injection head at the distal end of the injection shaft, the injection head comprising a flat surface that comprises the injection orifice. 
     
     
         16 . The needleless injector of  claim 14 , wherein the needless injector comprises an injection head at the distal end of the injection shaft, the injection head comprising multiple injection orifices. 
     
     
         17 . A method of treating tissue, the method comprising the steps of:
 providing the needleless injector of  claim 14  for insertion into a patient;   inserting the injection shaft into a body so the injection orifice is located adjacent the tissue to be treated;   actuating the tissue tensioner to contact body tissue in a vicinity of the tissue to be treated; and   injecting fluid from the injection orifice directly onto a surface of the tissue to be treated or into the tissue to be treated.   
     
     
         18 . The method of  claim 17 , wherein the step of inserting the injection shaft into the body comprises preparing an external incision and a tissue path leading to the tissue to be treated. 
     
     
         19 . The method of  claim 17 , wherein the step of inserting the injection shaft into the body comprises inserting the injection shaft into an exterior body opening leading to the tissue to be treated. 
     
     
         20 . The method of  claim 17 , wherein treating tissue is selected from the group of tissue consisting of bladder tissue, urethral tissue, kidney tissue, ureteral tissue and prostate tissue.