Sealed neurovascular extendable catheter

Abstract

A catheter is provided which includes an outer catheter and an extendable inner catheter. A sealing feature is positioned between the inner catheter and the outer catheter to seal the annular gap between the two while allowing axial translation. The seal may be a compliant protrusion surrounding the inner catheter and may have a chevron-shape for facilitating axial translation. The seal may be a one-way valve configured to allow antegrade flushing but prevent retrograde flow. The seal may be squeegee-like flange on the distal tip of the outer catheter. The seal may be an expandable bulge, which may be mechanically expandable or inflatable or which may be a photosensitive or electrosensitive hydrogel. The seal may include a spring that is radially compressed upon translation or rotation of the inner catheter to transiently break the seal. Also provided is a seal for sealing between the catheter and the vasculature.

1 . A sealed neurovascular extendable catheter comprising:
 an outer catheter having a proximal end and a distal end;   an inner catheter having a proximal end and a distal end and extendable through the outer catheter such that the distal end of the inner catheter is configured to extend beyond the distal end of the outer catheter;   an annular gap between an outer surface of the inner catheter and an inner surface of the outer catheter; and   a seal positioned between the inner catheter and the outer catheter and configured to fluidly seal at least a portion of a length of the annular gap, the seal having a proximal edge, a distal edge and a thickness configured to allow axial translation of the inner catheter relative to the outer catheter;   wherein the distal edge has a leading point and a trailing point, and the leading point is displaced axially distally relative to the trailing point.   
     
     
         2 . The sealed neurovascular extendable catheter of  claim 1 , wherein the seal comprises at least one annular protrusion extending around a circumference of the inner catheter, and wherein the protrusion is a skirt-shaped protrusion, the skirt-shaped protrusion configured to allow distal fluid flow but not proximal fluid flow through the sealing feature. 
     
     
         3 . The sealed neurovascular extendable catheter of  claim 1 , wherein the sealing feature comprises an expandable bulge surrounding a circumference of the inner catheter, the expandable bulge comprising a sealed configuration in which an outer diameter of the expandable bulge seals the annular gap and an unsealed configuration in which the outer diameter of the expandable bulge does not seal the annular gap. 
     
     
         4 . The sealed neurovascular extendable catheter of  claim 3 , wherein the expandable bulge is mechanically expandable. 
     
     
         5 . The sealed neurovascular extendable catheter of  claim 4 , wherein the expandable bulge is positioned at a proximal end of the inner catheter, and wherein a tension cable is joined to the expandable bulge at or near a distal end of the expandable bulge, and wherein pulling the tension cable proximally is configured to axially contract and radially expand the expandable bulge. 
     
     
         6 . The sealed neurovascular extendable catheter of  claim 3 , wherein the expandable bulge is expandable in response to receiving an electric current. 
     
     
         7 . The sealed neurovascular extendable catheter of  claim 3 , wherein the expandable bulge is expandable in response to stimulation by light. 
     
     
         8 . The sealed neurovascular extendable catheter of  claim 3 , wherein the expandable bulge is inflatable. 
     
     
         9 . The sealed neurovascular extendable catheter of  claim 3 , wherein the inner catheter comprises a proximal spine comprising a lumen, the lumen being configured to transmit a stimulus to the expandable bulge for activating the expandable bulge and causing it to expand. 
     
     
         10 . The sealed neurovascular extendable catheter of  claim 1 , wherein the sealing feature comprises an elastic flange positioned at a distal tip of the outer catheter, the elastic flange having an inner diameter and the inner diameter of the elastic flange being smaller than an outer diameter of the inner catheter. 
     
     
         11 . The sealed neurovascular extendable catheter of  claim 1 , wherein the sealing feature comprises a hub of an expanded diameter positioned at a proximal end of the inner catheter, the hub configured to form an interference fit with an inner diameter of the outer catheter, and wherein the inner catheter comprises a proximal spine comprising a lumen, the lumen extending through the hub to form a fluid port through the sealing feature through which a flushing solution may be delivered to the annular gap in a space distal to the sealing feature. 
     
     
         12 . A neurovascular catheter for sealing a blood vessel, the neurovascular catheter comprising:
 an elongate body having a proximal end and a distal end; and   a sealing feature configured to fluidly seal an annular gap positioned between an outer surface of the elongate body and the blood vessel, the sealing feature comprising a compliant annular ring configured to be placed into compression with a wall of the blood vessel without damaging the blood vessel.   
     
     
         13 . The neurovascular catheter of  claim 12 , wherein the ring comprises an elastomeric polymer. 
     
     
         14 . The neurovascular catheter of  claim 12 , wherein the ring comprises a hydrogel. 
     
     
         15 . The neurovascular catheter of  claim 14 , wherein the hydrogel is electrosensitive and configured to expand upon receiving an electric current. 
     
     
         16 . The neurovascular catheter of  claim 14 , wherein the hydrogel is configured to expand upon exposure the intravascular physiological environment. 
     
     
         17 . The neurovascular catheter of  claim 12 , wherein the ring is inflatable. 
     
     
         18 . The neurovascular catheter of  claim 12 , wherein the outer surface of the elongate body comprises a recess for receiving the ring. 
     
     
         19 . The neurovascular catheter of  claim 12 , wherein the ring is detachable from the elongate body. 
     
     
         20 . The neurovascular catheter of  claim 12 , further comprising a replacement ring that is sized differently from the ring and interchangeable with the ring.