Fluid exchange apparatus for expandable port delivery system and methods of use

Abstract

A device for injecting a therapeutic agent into an ocular implant at least partially implanted in an eye including an injection lumen providing a pathway for injecting the therapeutic agent into the implant; an outlet lumen providing a pathway for pre-existing fluid in the ocular implant to exit the implant; and a collection chamber fluidly coupled to the outlet lumen that provides a first fluid outflow resistance and a second fluid outflow resistance. The first fluid outflow resistance is lower than a first resistance to outflow of the implant. The second fluid outflow resistance is greater than a force imparted onto the implant by intraocular pressure of the eye. Injection of therapeutic agent into the implant via the injection lumen causes the pre-existing fluid to exit the implant and enter the collection chamber via the outlet lumen and causes a second pre-existing fluid to displace from the collection chamber.

1 .- 20 . (canceled) 
     
     
         21 . An exchange device for use with a syringe, the exchange device comprising:
 a needle hub assembly configured to couple with the syringe;   a needle coupled to and projecting distal from the needle hub assembly, the needle comprising:
 an injection lumen configured to provide a pathway for injecting a therapeutic agent into an ocular implant, the ocular implant at least partially implanted in an eye and providing at least a first resistance to outflow of therapeutic agent into the eye; and 
 an outlet lumen configured to provide a pathway through which liquid in the ocular implant exits the ocular implant as it is displaced by the therapeutic agent; and 
   a collection chamber in fluid communication with the outlet lumen so as to receive the liquid displaced from the ocular implant via the outlet lumen,   wherein the collection chamber comprises a spacer ring positioned within an upper end region of the collection chamber, the spacer ring having an inner diameter sized to encircle a portion of the needle hub assembly and an outer diameter sized to engage a wall of the collection chamber, wherein a porous structure is positioned within a region of the spacer ring.   
     
     
         22 . The exchange device of  claim 21 , wherein the spacer ring forms a cap creating a fixed upper limit of the collection chamber that together with the wall defines a volume of the collection chamber. 
     
     
         23 . The exchange device of  claim 21 , wherein the wall surrounds at least a portion of the needle in a concentric manner. 
     
     
         24 . The exchange device of  claim 21 , wherein the wall flares out beyond a diameter of the syringe. 
     
     
         25 . The exchange device of  claim 21 , wherein the volume of the collection chamber is up to about 200 uL. 
     
     
         26 . The exchange device of  claim 21 , wherein the porous structure comprises a rigid structure formed of a material having a low resistance to gas flow and a high resistance to liquid. 
     
     
         27 . The exchange device of  claim 21 , wherein the collection chamber provides a first fluid outflow resistance to gas outflow and a second fluid outflow resistance to liquid outflow, wherein the first fluid outflow resistance is lower than the first resistance to outflow of the ocular implant, and the second fluid outflow resistance is greater than a force imparted onto the ocular implant by intraocular pressure of the eye, and wherein injection of therapeutic agent into the ocular implant via the injection lumen causes the liquid to exit the ocular implant and enter the collection chamber via the outlet lumen and displaces a fluid from the collection chamber. 
     
     
         28 . The exchange device of  claim 27 , wherein the fluid is air. 
     
     
         29 . The exchange device of  claim 27 , wherein the fluid is displaced from the collection chamber via a vent. 
     
     
         30 . The exchange device of  claim 27 , wherein the fluid is displaced from the collection chamber via a valve. 
     
     
         31 . The exchange device of  claim 27 , wherein the implant is expandable once implanted in the eye from a first, collapsed configuration to a second, enlarged configuration. 
     
     
         32 . The exchange device of  claim 27 , wherein the porous structure of the spacer ring has the first fluid outflow resistance to gas outflow and the second fluid outflow resistance to liquid outflow. 
     
     
         33 . The exchange device of  claim 32 , wherein the ocular implant comprises a second porous structure that provides the first resistance to outflow. 
     
     
         34 . The exchange device of  claim 33 , wherein the first fluid outflow resistance of the porous structure of the spacer ring is less than the first resistance provided by the second porous structure of the ocular implant, and the second fluid outflow resistance of the porous structure of the spacer ring is greater than the first resistance of the ocular implant. 
     
     
         35 . The exchange device of  claim 33 , wherein the ocular implant is expandable once implanted in the eye from a first, collapsed configuration to a second, enlarged configuration, wherein the porous structure of the spacer ring prevents collapse of the ocular implant away from the second, enlarged configuration after filling. 
     
     
         36 . The exchange device of  claim 33 , wherein the porous structure of the spacer ring is a hydrophobic membrane, a fabric, a porous fabric, a semipermeable membrane, an air permeable material, a moisture vapor transfer waterproof fabric, a hydrophilic porous material, or a porous sintered material. 
     
     
         37 . A method for exchanging liquids of an ocular implant with an exchange needle device, the ocular implant having a reservoir that is at least partially implanted in an eye, and further providing at least a first resistance to outflow of therapeutic agent into the eye, the method comprising:
 inserting a needle of the exchange needle device into the reservoir of the ocular implant;   injecting therapeutic agent into the reservoir through an injection lumen of the needle thereby displacing a pre-existing liquid from the ocular implant into an outlet lumen of the needle;   collecting the pre-existing liquid within a collection chamber of the exchange needle device, the collection chamber in fluid communication with the outlet lumen, wherein the collection chamber comprises an annular element positioned near an upper end of the collection chamber forming a fixed upper limit to the collection chamber and having a first porous structure positioned within a region of the annular element; and   preventing the reservoir from collapsing after filling the reservoir with therapeutic agent and before withdrawal of the needle from the reservoir due to a force imparted onto the reservoir by intraocular pressure of the eye.   
     
     
         38 . The method of  claim 37 , wherein the first porous structure of the annular element provides a first fluid outflow resistance to gas outflow and a second fluid outflow resistance to liquid outflow, wherein the first fluid outflow resistance is lower than the first resistance to outflow of the ocular implant, and the second fluid outflow resistance is greater than the force imparted onto the ocular implant by intraocular pressure of the eye. 
     
     
         39 . The method of  claim 38 , wherein injecting therapeutic agent into the reservoir through the injection lumen displaces the pre-existing liquid into the outlet lumen and causes a pre-existing fluid to displace from the collection chamber through the first porous structure. 
     
     
         40 . The method of  claim 39 , wherein the pre-existing fluid is a gas. 
     
     
         41 . The method of  claim 40 , wherein the gas is air. 
     
     
         42 . The method of  claim 37 , wherein the reservoir of the ocular implant is expandable from a first, collapsed configuration to a second, enlarged configuration, wherein preventing the reservoir from collapsing after filling comprises preventing movement of the reservoir away from the second, enlarged configuration toward the first, collapsed configuration upon wetting of the first porous structure with the pre-existing liquid. 
     
     
         43 . The method of  claim 37 , wherein the ocular implant comprises a second porous structure that provides the first resistance to outflow. 
     
     
         44 . The method of  claim 43 , wherein the first fluid outflow resistance of the first porous structure is less than the first resistance to outflow provided by the second porous structure of the ocular implant, and the second fluid outflow resistance of the first porous structure is greater than the first resistance to outflow provided by the second porous structure of the ocular implant. 
     
     
         45 . An exchange device for use with a syringe, the exchange device comprising:
 a needle hub assembly configured to couple with the syringe;   a needle coupled to and projecting from the needle hub assembly having a distal tip surrounding a longitudinal axis, the needle configured to inject therapeutic agent into an ocular implant that is at least partially implanted in an eye; and   a collection chamber within a body offset from the longitudinal axis, the collection chamber configured to receive liquid expelled from the ocular implant as therapeutic agent is injected through the needle, wherein the collection chamber is a tubular structure having a lumen extending from an opening into the tubular structure to a porous structure positioned at a terminus of the lumen.   
     
     
         46 . The exchange device of  claim 45 , further comprising a needle cannula passage extending along a first axis at a proximal end region and a second axis at a distal end region, wherein the second axis is concentric with the longitudinal axis and wherein the first axis at the proximal end region of the needle cannula passage is not concentric with the longitudinal axis. 
     
     
         47 . The exchange device of  claim 46 , wherein the needle is routed from the first axis to the second axis away from the body that is offset from the longitudinal axis so that the distal tip of the needle is not concentric with the needle hub assembly. 
     
     
         48 . The exchange device of  claim 45 , wherein the tubular structure has an inner diameter that is uniform over a length of the tubular structure from the opening to the terminus. 
     
     
         49 . The exchange device of  claim 46 , wherein the inner diameter of the tubular structure is 0.125″-0.500″ and wherein the length of the tubular structure is 0.5″-3.0″. 
     
     
         50 . The exchange device of  claim 45 , wherein the tubular structure has a first inner diameter near the opening and a second inner diameter near the terminus, the second inner diameter being larger than the first inner diameter. 
     
     
         51 . The exchange device of  claim 45 , wherein the body wraps around a barrel of the syringe when the exchange device is coupled to the syringe. 
     
     
         52 . The exchange device of  claim 45 , wherein the body of the collection chamber tapers to a narrower size near the opening into the lumen. 
     
     
         53 . The exchange device of  claim 45 , wherein the body of the collection chamber is configured to be positioned side-by-side with a barrel of the syringe upon coupling to the syringe. 
     
     
         54 . The exchange device of  claim 45 , wherein the collection chamber has a volume of at least about 200 uL up to about 400 uL. 
     
     
         55 . The exchange device of  claim 45 , wherein the tubular structure is coiled. 
     
     
         56 . The exchange device of  claim 55 , wherein the tubular structure provides a uniform fill pattern that minimizes trapping of fluid displaced from the collection chamber as it receives the liquid expelled from the ocular implant. 
     
     
         57 . The exchange device of  claim 45 , wherein the porous structure positioned at the terminus of the lumen provides a first fluid outflow resistance to gas outflow and a second fluid outflow resistance to liquid outflow. 
     
     
         58 . The exchange device of  claim 57 , wherein the first fluid outflow resistance is lower than a first resistance to outflow of the ocular implant, and the second fluid outflow resistance is greater than a force imparted onto the ocular implant by intraocular pressure of the eye. 
     
     
         59 . The exchange device of  claim 58 , wherein the ocular implant is expandable from a first, collapsed configuration to a second, enlarged configuration, and wherein the ocular implant is prevented from collapsing from the second, enlarge configuration after filling towards the first, collapsed configuration upon wetting of the porous structure near the terminus.