System and method for resistance-dependent, self-regulated medical penetration

Abstract

A system for delivering an injection of a fluid into a void within a subject is disclosed. A barrel extends from a first end to a second end and forms a lumen extending from the first end to the second end. A plug and a floating seal are arranged within the lumen. A hollow needle includes a distal end with an opening for fluid to flow from the lumen. The plug, the barrel and the floating seal include material and dimensions selected based on a threshold flowrate for a fluid arranged within the lumen to: overcome a force opposed to a force being applied to the fluid in the lumen to move the floating seal and the hollow needle into a tissue of the subject, and succumb to the opposing force to displace the fluid through the opening into the void.

1 - 20 . (canceled) 
     
     
         21 . A system comprising:
 a syringe barrel forming a lumen from a distal end to a proximal end of the syringe barrel;   a plug arranged in the lumen such that the plug is configured to form a seal in the lumen of the syringe barrel;   a floating seal arranged in the lumen distal of the plug to define a fluid chamber between the floating seal and the plug; and   a needle extending distally from the floating seal and configured to allow a fluid from the fluid chamber to flow from the lumen;   wherein the syringe barrel, the plug, and the floating seal are configured such that, upon a force being applied on the plug in a distal direction,
 during a tissue penetration phase, a distal end of the needle advances through a tissue at a threshold rate without releasing the fluid from the lumen due to a first opposing force, and 
 during a cavity penetration phase, the distal end of the needle extends through the tissue and into a cavity such that the fluid is injected from the fluid chamber into the cavity at a threshold flowrate as a position of the distal end of the needle is maintained due to a second opposing force different than the first opposing force. 
   
     
     
         22 . The system of  claim 21 , wherein the cavity is pressurized, empty, fluid filled, porous, or potential space created by delamination of layers. 
     
     
         23 . The system of  claim 21 , wherein the fluid is a first fluid, the system further comprising a drainage of a second fluid. 
     
     
         24 . The system of  claim 21 , wherein the syringe barrel forms a single-handed injector. 
     
     
         25 . The system of  claim 21 , wherein the syringe barrel is formed of two barrels coupled together by a lock connector, a flexible tube, or a rigid tube. 
     
     
         26 . The system of  claim 21 , further comprising a back support extending into the lumen of the syringe barrel to restrict the floating seal from extending through the lumen toward the proximal end of the syringe barrel beyond the back support. 
     
     
         27 . The system of  claim 21 , further comprising at least one of: a fluid connection extending through the plug to deliver the force via the fluid connection; a plunger arm extending from the plug to apply the force through the plunger arm; and a mechanical actuator configured to deliver the force by releasing potential energy stored in the mechanical actuator. 
     
     
         28 . The system of  claim 21 , wherein the needle is configured to extend beyond the distal end of the syringe barrel to expose a portion of the needle for insertion into the tissue of the subject before applying the force. 
     
     
         29 . The system of  claim 21 , wherein the needle extends through the floating seal or is aligned with a passage extending through the floating seal to present a fluid passage from the lumen in the syringe barrel to the opening in the needle. 
     
     
         30 . The system of  claim 21 , wherein the needle includes threads forming a drill or a sharpened tip forming a knife point. 
     
     
         31 . The system of  claim 21 , wherein the fluid includes a liquid, a gas, a combination of liquid and gas, liquid-suspended particles, gel, gel-suspended particles, micro-particles, or nano-particles. 
     
     
         32 . The system of  claim 21 , wherein a portion of the lumen between the plug and the floating seal forms a volume of one of 1 ml, 3 ml, 5 ml, or 10 ml prior to displacement of the fluid. 
     
     
         33 . The system of  claim 21 , wherein the first opposing force includes at least one of a frictional force between the floating seal and the syringe barrel, a frictional force of the tissue of the subject or a spring based mechanical force. 
     
     
         34 . The system of  claim 21 , wherein the threshold flowrate includes a minimum flowrate sufficient to enable the needle to move in the cavity. 
     
     
         35 . A method comprising:
 inserting a distal end of a needle of a syringe into a tissue, the syringe comprising a syringe barrel forming a lumen from a distal end to a proximal end of the syringe barrel and a plug arranged in the lumen such that the plug is configured to form a seal in the lumen of the syringe barrel and a floating seal arranged in the lumen distal of the plug to define a fluid chamber between the floating seal and the plug, wherein the needle extends distally from the floating seal and configured to allow a fluid from the fluid chamber to flow from the lumen;   advancing a distal end of the needle, during a tissue penetration phase, through the tissue at a threshold rate without releasing the fluid from the lumen due to a first opposing force; and   injecting the fluid from the fluid chamber, during a cavity penetration phase when the distal end of the needle extends through the tissue and into a cavity, into the cavity at a threshold flowrate such that a position of the distal end of the needle is maintained due to a second opposing force different than the first opposing force.   
     
     
         36 . method of  claim 35 , wherein the cavity is formed by a suprachoroidal space between a sclera and a choroid of an eye of the subject. 
     
     
         37 . The method of  claim 35 , wherein the fluid includes a therapeutic for a posterior segment eye disease. 
     
     
         38 . The method of  claim 37 , wherein the posterior segment eye disease includes one of macular degeneration (AMD), diabetic retinopathy (DR), diabetic macular edema (DME), retinal vein occlusion (RVO), uveitis, or endophthalmitis. 
     
     
         39 . A system comprising:
 a syringe barrel forming a lumen from a distal end to a proximal end of the syringe barrel;   a plug arranged in the lumen such that the plug is configured to form a seal in the lumen of the syringe barrel;   a floating seal arranged in the lumen distal of the plug to define a fluid chamber between the floating seal and the plug; and   a penetrating device including a passage extending from a proximal end connected to the floating seal to a distal end having an opening for the fluid to flow from the lumen, through the floating seal, and through the distal end of the syringe barrel via the penetrating device; and   wherein the syringe barrel, the plug, and the floating seal are configured such that, upon a force being applied on the plug in a distal direction,
 during a tissue penetration phase, a distal end of the needle advances through a tissue at a threshold rate without releasing the fluid from the lumen due to a first opposing force, and 
 during a cavity penetration phase, the distal end of the needle extends through the tissue and into a cavity such that the fluid is injected from the fluid chamber into the cavity at a threshold flowrate as a position of the distal end of the needle is maintained due to a second opposing force different than the first opposing force.